WorldWideScience

Sample records for integrated guidance navigation

  1. Radio/FADS/IMU integrated navigation for Mars entry

    Science.gov (United States)

    Jiang, Xiuqiang; Li, Shuang; Huang, Xiangyu

    2018-03-01

    Supposing future orbiting and landing collaborative exploration mission as the potential project background, this paper addresses the issue of Mars entry integrated navigation using radio beacon, flush air data sensing system (FADS), and inertial measurement unit (IMU). The range and Doppler information sensed from an orbiting radio beacon, the dynamic pressure and heating data sensed from flush air data sensing system, and acceleration and attitude angular rate outputs from an inertial measurement unit are integrated in an unscented Kalman filter to perform state estimation and suppress the system and measurement noise. Computer simulations show that the proposed integrated navigation scheme can enhance the navigation accuracy, which enables precise entry guidance for the given Mars orbiting and landing collaborative exploration mission.

  2. Integrated software health management for aerospace guidance, navigation, and control systems: A probabilistic reasoning approach

    Science.gov (United States)

    Mbaya, Timmy

    Embedded Aerospace Systems have to perform safety and mission critical operations in a real-time environment where timing and functional correctness are extremely important. Guidance, Navigation, and Control (GN&C) systems substantially rely on complex software interfacing with hardware in real-time; any faults in software or hardware, or their interaction could result in fatal consequences. Integrated Software Health Management (ISWHM) provides an approach for detection and diagnosis of software failures while the software is in operation. The ISWHM approach is based on probabilistic modeling of software and hardware sensors using a Bayesian network. To meet memory and timing constraints of real-time embedded execution, the Bayesian network is compiled into an Arithmetic Circuit, which is used for on-line monitoring. This type of system monitoring, using an ISWHM, provides automated reasoning capabilities that compute diagnoses in a timely manner when failures occur. This reasoning capability enables time-critical mitigating decisions and relieves the human agent from the time-consuming and arduous task of foraging through a multitude of isolated---and often contradictory---diagnosis data. For the purpose of demonstrating the relevance of ISWHM, modeling and reasoning is performed on a simple simulated aerospace system running on a real-time operating system emulator, the OSEK/Trampoline platform. Models for a small satellite and an F-16 fighter jet GN&C (Guidance, Navigation, and Control) system have been implemented. Analysis of the ISWHM is then performed by injecting faults and analyzing the ISWHM's diagnoses.

  3. Sensors and sensor systems for guidance and navigation II; Proceedings of the Meeting, Orlando, FL, Apr. 22, 23, 1992

    Science.gov (United States)

    Welch, Sharon S.

    Topics discussed in this volume include aircraft guidance and navigation, optics for visual guidance of aircraft, spacecraft and missile guidance and navigation, lidar and ladar systems, microdevices, gyroscopes, cockpit displays, and automotive displays. Papers are presented on optical processing for range and attitude determination, aircraft collision avoidance using a statistical decision theory, a scanning laser aircraft surveillance system for carrier flight operations, star sensor simulation for astroinertial guidance and navigation, autonomous millimeter-wave radar guidance systems, and a 1.32-micron long-range solid state imaging ladar. Attention is also given to a microfabricated magnetometer using Young's modulus changes in magnetoelastic materials, an integrated microgyroscope, a pulsed diode ring laser gyroscope, self-scanned polysilicon active-matrix liquid-crystal displays, the history and development of coated contrast enhancement filters for cockpit displays, and the effect of the display configuration on the attentional sampling performance. (For individual items see A93-28152 to A93-28176, A93-28178 to A93-28180)

  4. Guidance and navigation for rendezvous with an uncooperative target

    Science.gov (United States)

    Telaar, J.; Schlaile, C.; Sommer, J.

    2018-06-01

    This paper presents a guidance strategy for a rendezvous with an uncooperative target. In the applied design reference mission, a spiral approach is commanded ensuring a collision-free relative orbit due to e/i-vector separation. The dimensions of the relative orbit are successively reduced by Δv commands which at the same time improve the observability of the relative state. The navigation is based on line-of-sight measurements. The relative state is estimated by an extended Kalman filter (EKF). The performance of this guidance and navigation strategy is demonstrated by extensive Monte Carlo simulations taking into account all major uncertainties like measurement errors, Δv execution errors, and differential drag.

  5. Integrated navigation of aerial robot for GPS and GPS-denied environment

    International Nuclear Information System (INIS)

    Suzuki, Satoshi; Min, Hongkyu; Nonami, Kenzo; Wada, Tetsuya

    2016-01-01

    In this study, novel robust navigation system for aerial robot in GPS and GPS- denied environments is proposed. Generally, the aerial robot uses position and velocity information from Global Positioning System (GPS) for guidance and control. However, GPS could not be used in several environments, for example, GPS has huge error near buildings and trees, indoor, and so on. In such GPS-denied environment, Laser Detection and Ranging (LIDER) sensor based navigation system have generally been used. However, LIDER sensor also has an weakness, and it could not be used in the open outdoor environment where GPS could be used. Therefore, it is desired to develop the integrated navigation system which is seamlessly applied to GPS and GPS-denied environments. In this paper, the integrated navigation system for aerial robot using GPS and LIDER is developed. The navigation system is designed based on Extended Kalman Filter, and the effectiveness of the developed system is verified by numerical simulation and experiment. (paper)

  6. Integrated CLOS and PN Guidance for Increased Effectiveness of Surface to Air Missiles

    Directory of Open Access Journals (Sweden)

    Binte Fatima Tuz ZAHRA

    2017-06-01

    Full Text Available In this paper, a novel approach has been presented to integrate command to line-of-sight (CLOS guidance and proportional navigation (PN guidance in order to reduce miss distance and to increase the effectiveness of surface to air missiles. Initially a comparison of command to line-of-sight guidance and proportional navigation has been presented. Miss distance, variation of angle-of-attack, normal and lateral accelerations and error of missile flight path from direct line-of-sight have been used as noteworthy criteria for comparison of the two guidance laws. Following this comparison a new approach has been proposed for determining the most suitable guidance gains in order to minimize miss distance and improve accuracy of the missile in delivering the warhead, while using CLOS guidance. This proposed technique is based on constrained nonlinear minimization to optimize the guidance gains. CLOS guidance has a further limitation of significant increase in normal and lateral acceleration demands during the terminal phase of missile flight. Furthermore, at large elevation angles, the required angle-of-attack during the terminal phase increases beyond design specifications. Subsequently, a missile with optical sensors only and following just the CLOS guidance has less likelihood to hit high speed targets beyond 45º in elevation plane. A novel approach has thus been proposed to overcome such limitations of CLOS-only guidance for surface to air missiles. In this approach, an integrated guidance algorithm has been proposed whereby the initial guidance law during rocket motor burnout phase remains CLOS, whereas immediately after this phase, the guidance law is automatically switched to PN guidance. This integrated approach has not only resulted in slight increase in range of the missile but also has significantly improved its likelihood to hit targets beyond 30 degrees in elevation plane, thus successfully overcoming various limitations of CLOS

  7. A novel biased proportional navigation guidance law for close approach phase

    Directory of Open Access Journals (Sweden)

    Su Wenshan

    2016-02-01

    Full Text Available A novel biased proportional navigation guidance (BPNG law is proposed for the close approach phase, which aims to make the spacecraft rendezvous with the target in specific relative range and direction. Firstly, in order to describe the special guidance requirements, the concept of zero effort miss vector is proposed and the dangerous area where there exists collision risk for safety consideration is defined. Secondly, the BPNG, which decouples the range control and direction control, is designed in the line-of-sight (LOS rotation coordinate system. The theoretical analysis proves that BPNG meets guidance requirements quite well. Thirdly, for the consideration of fuel consumption, the optimal biased proportional navigation guidance (OBPNG law is derived by solving the Schwartz inequality. Finally, simulation results show that BPNG is effective for the close approach with the ability of evading the dangerous area and OBPNG consumes less fuel compared with BPNG.

  8. Sugar Antennae for Guidance Signals: Syndecans and Glypicans Integrate Directional Cues for Navigating Neurons

    Directory of Open Access Journals (Sweden)

    Christa Rhiner

    2006-01-01

    Full Text Available Attractive and repulsive signals guide migrating nerve cells in all directions when the nervous system starts to form. The neurons extend thin processes, axons, that connect over wide distances with other brain cells to form a complicated neuronal network. One of the most fascinating questions in neuroscience is how the correct wiring of billions of nerve cells in our brain is controlled. Several protein families are known to serve as guidance cues for navigating neurons and axons. Nevertheless, the combinatorial potential of these proteins seems to be insufficient to sculpt the entire neuronal network and the appropriate formation of connections. Recently, heparan sulfate proteoglycans (HSPGs, which are present on the cell surface of neurons and in the extracellular matrix through which neurons and axons migrate, have been found to play a role in regulating cell migration and axon guidance. Intriguingly, the large number of distinct modifications that can be put onto the sugar side chains of these PGs would in principle allow for an enormous diversity of HSPGs, which could help in regulating the vast number of guidance choices taken by individual neurons. In this review, we will focus on the role of the cell surface HSPGs syndecan and glypican and specific HS modifications in promoting neuronal migration, axon guidance, and synapse formation.

  9. A novel approach for navigational guidance of ships using onboard monitoring systems

    DEFF Research Database (Denmark)

    Nielsen, Ulrik Dam; Jensen, Jørgen Juncher

    2011-01-01

    A novel approach and conceptual ideas are outlined for risk-based navigational guidance of ships using decision support systems in combination with onboard, in-service monitoring systems. The guidance has as the main objective to advise on speed and/or course changes; in particular with focus...

  10. NASA LaRC Workshop on Guidance, Navigation, Controls, and Dynamics for Atmospheric Flight, 1993

    Science.gov (United States)

    Buttrill, Carey S. (Editor)

    1993-01-01

    This publication is a collection of materials presented at a NASA workshop on guidance, navigation, controls, and dynamics (GNC&D) for atmospheric flight. The workshop was held at the NASA Langley Research Center on March 18-19, 1993. The workshop presentations describe the status of current research in the GNC&D area at Langley over a broad spectrum of research branches. The workshop was organized in eight sessions: overviews, general, controls, military aircraft, dynamics, guidance, systems, and a panel discussion. A highlight of the workshop was the panel discussion which addressed the following issue: 'Direction of guidance, navigation, and controls research to ensure U.S. competitiveness and leadership in aerospace technologies.'

  11. Guidance, navigation, and control subsystem for the EOS-AM spacecraft

    Science.gov (United States)

    Linder, David M.; Tolek, Joseph T.; Lombardo, John

    1992-01-01

    This paper presents the preliminary design of the Guidance, Navigation, and Control (GN&C) subsystem for the EOS-AM spacecraft and specifically focuses on the GN&C Normal Mode design. First, a brief description of the EOS-AM science mission, instruments, and system-level spacecraft design is provided. Next, an overview of the GN&C subsystem functional and performance requirements, hardware, and operating modes is presented. Then, the GN&C Normal Mode attitude determination, attitude control, and navigation systems are detailed. Finally, descriptions of the spacecraft's overall jitter performance and Safe Mode are provided.

  12. Project Management Using Modern Guidance, Navigation and Control Theory

    Science.gov (United States)

    Hill, Terry

    2010-01-01

    The idea of control theory and its application to project management is not new, however literature on the topic and real-world applications is not as readily available and comprehensive in how all the principals of Guidance, Navigation and Control (GN&C) apply. This paper will address how the fundamental principals of modern GN&C Theory have been applied to NASA's Constellation Space Suit project and the results in the ability to manage the project within cost, schedule and budget. A s with physical systems, projects can be modeled and managed with the same guiding principles of GN&C as if it were a complex vehicle, system or software with time-varying processes, at times non-linear responses, multiple data inputs of varying accuracy and a range of operating points. With such systems the classic approach could be applied to small and well-defined projects; however with larger, multi-year projects involving multiple organizational structures, external influences and a multitude of diverse resources, then modern control theory is required to model and control the project. The fundamental principals of G N&C stated that a system is comprised of these basic core concepts: State, Behavior, Control system, Navigation system, Guidance and Planning Logic, Feedback systems. The state of a system is a definition of the aspects of the dynamics of the system that can change, such as position, velocity, acceleration, coordinate-based attitude, temperature, etc. The behavior of the system is more of what changes are possible rather than what can change, which is captured in the state of the system. The behavior of a system is captured in the system modeling and if properly done, will aid in accurate system performance prediction in the future. The Control system understands the state and behavior of the system and feedback systems to adjust the control inputs into the system. The Navigation system takes the multiple data inputs and based upon a priori knowledge of the input

  13. Landmarks or panoramas: what do navigating ants attend to for guidance?

    Directory of Open Access Journals (Sweden)

    Beugnon Guy

    2011-08-01

    Full Text Available Abstract Background Insects are known to rely on terrestrial landmarks for navigation. Landmarks are used to chart a route or pinpoint a goal. The distant panorama, however, is often thought not to guide navigation directly during a familiar journey, but to act as a contextual cue that primes the correct memory of the landmarks. Results We provided Melophorus bagoti ants with a huge artificial landmark located right near the nest entrance to find out whether navigating ants focus on such a prominent visual landmark for homing guidance. When the landmark was displaced by small or large distances, ant routes were affected differently. Certain behaviours appeared inconsistent with the hypothesis that guidance was based on the landmark only. Instead, comparisons of panoramic images recorded on the field, encompassing both landmark and distal panorama, could explain most aspects of the ant behaviours. Conclusion Ants navigating along a familiar route do not focus on obvious landmarks or filter out distal panoramic cues, but appear to be guided by cues covering a large area of their panoramic visual field, including both landmarks and distal panorama. Using panoramic views seems an appropriate strategy to cope with the complexity of natural scenes and the poor resolution of insects' eyes. The ability to isolate landmarks from the rest of a scene may be beyond the capacity of animals that do not possess a dedicated object-perception visual stream like primates.

  14. Bezier-curve Navigation Guidance for Impact Time and Angle Control

    Directory of Open Access Journals (Sweden)

    Gun-Hee MOON

    2018-03-01

    Full Text Available This paper addresses a novel impact time and angle control guidance law using a Bézier curve. The 2nd order Bézier curve consists of one control point and two boundary points; initial point P0, middle point P1 and end point P2. The curve is tangent to the line P0-P1 and the line P1-P2, respectively, and always exists in the convex hull of the control points. Proposed Bézier curve navigation guidance, makes the missile follow the Bézier curve with the feedback form of guidance command so that the missile hits the target on the desired time in the desired direction. We conducted numerical simulations on several terminal conditions to demonstrate the performance of proposed method.

  15. A Qualitative Comparison between the Proportional Navigation and Differential Geometry Guidance Algorithms

    Directory of Open Access Journals (Sweden)

    Yunes Sh. ALQUDSI

    2018-06-01

    Full Text Available This paper discusses and presents an overview of the proportional navigation (PN guidance law as well as the differential geometry (DG guidance algorithm that are used to develop the intercept course of a certain target. The intent of this study is to illustrate the advantages of the guidance algorithm generated based on the concepts of differential geometry against the well-known PN guidance law. The basic principles behind the both algorithms are mentioned. Moreover, the different versions of the PN approach is briefly clarified to show the essential improvement from one version to the other. The paper terminated with numerous two-dimension simulation figures to give a great value of visual aids, illustrating the significant relations and main features and properties of both algorithms.

  16. Guidance, Navigation, and Control Techniques and Technologies for Active Satellite Removal

    Science.gov (United States)

    Ortega Hernando, Guillermo; Erb, Sven; Cropp, Alexander; Voirin, Thomas; Dubois-Matra, Olivier; Rinalducci, Antonio; Visentin, Gianfranco; Innocenti, Luisa; Raposo, Ana

    2013-09-01

    This paper shows an internal feasibility analysis to de- orbit a non-functional satellite of big dimensions by the Technical Directorate of the European Space Agency ESA. The paper focuses specifically on the design of the techniques and technologies for the Guidance, Navigation, and Control (GNC) system of the spacecraft mission that will capture the satellite and ultimately will de-orbit it on a controlled re-entry.The paper explains the guidance strategies to launch, rendezvous, close-approach, and capture the target satellite. The guidance strategy uses chaser manoeuvres, hold points, and collision avoidance trajectories to ensure a safe capture. It also details the guidance profile to de-orbit it in a controlled re-entry.The paper continues with an analysis of the required sensing suite and the navigation algorithms to allow the homing, fly-around, and capture of the target satellite. The emphasis is placed around the design of a system to allow the rendezvous with an un-cooperative target, including the autonomous acquisition of both the orbital elements and the attitude of the target satellite.Analysing the capture phase, the paper provides a trade- off between two selected capture systems: the net and the tentacles. Both are studied from the point of view of the GNC system.The paper analyses as well the advanced algorithms proposed to control the final compound after the capture that will allow the controlled de-orbiting of the assembly in a safe place in the Earth.The paper ends proposing the continuation of this work with the extension to the analysis of the destruction process of the compound in consecutive segments starting from the entry gate to the rupture and break up.

  17. Low Cost Integrated Navigation System for Unmanned Vessel

    Directory of Open Access Journals (Sweden)

    Yang Changsong

    2017-11-01

    Full Text Available Large errors of low-cost MEMS inertial measurement unit (MIMU lead to huge navigation errors, even wrong navigation information. An integrated navigation system for unmanned vessel is proposed. It consists of a low-cost MIMU and Doppler velocity sonar (DVS. This paper presents an integrated navigation method, to improve the performance of navigation system. The integrated navigation system is tested using simulation and semi-physical simulation experiments, whose results show that attitude, velocity and position accuracy has improved awfully, giving exactly accurate navigation results. By means of the combination of low-cost MIMU and DVS, the proposed system is able to overcome fast drift problems of the low cost IMU.

  18. Rapid Development of Guidance, Navigation, and Control Core Flight System Software Applications Using Simulink Models

    Data.gov (United States)

    National Aeronautics and Space Administration — The goal of this proposal is to demonstrate a new Guidance, Navigation, and Control (GNC) Flight Software (FSW) application development paradigm which takes...

  19. Medical technology integration: CT, angiography, imaging-capable OR-table, navigation and robotics in a multifunctional sterile suite.

    Science.gov (United States)

    Jacob, A L; Regazzoni, P; Bilecen, D; Rasmus, M; Huegli, R W; Messmer, P

    2007-01-01

    Technology integration is an enabling technological prerequisite to achieve a major breakthrough in sophisticated intra-operative imaging, navigation and robotics in minimally invasive and/or emergency diagnosis and therapy. Without a high degree of integration and reliability comparable to that achieved in the aircraft industry image guidance in its different facets will not ultimately succeed. As of today technology integration in the field of image-guidance is close to nonexistent. Technology integration requires inter-departmental integration of human and financial resources and of medical processes in a dialectic way. This expanded techno-socio-economic integration has profound consequences for the administration and working conditions in hospitals. At the university hospital of Basel, Switzerland, a multimodality multifunction sterile suite was put into operation after a substantial pre-run. We report the lessons learned during our venture into the world of medical technology integration and describe new possibilities for similar integration projects in the future.

  20. Analysis of the Effects of Thermal Environment on Optical Systems for Navigation Guidance and Control in Supersonic Aircraft Based on Empirical Equations.

    Science.gov (United States)

    Cheng, Xuemin; Yang, Yikang; Hao, Qun

    2016-10-17

    The thermal environment is an important factor in the design of optical systems. This study investigated the thermal analysis technology of optical systems for navigation guidance and control in supersonic aircraft by developing empirical equations for the front temperature gradient and rear thermal diffusion distance, and for basic factors such as flying parameters and the structure of the optical system. Finite element analysis (FEA) was used to study the relationship between flying and front dome parameters and the system temperature field. Systematic deduction was then conducted based on the effects of the temperature field on the physical geometry and ray tracing performance of the front dome and rear optical lenses, by deriving the relational expressions between the system temperature field and the spot size and positioning precision of the rear optical lens. The optical systems used for navigation guidance and control in supersonic aircraft when the flight speed is in the range of 1-5 Ma were analysed using the derived equations. Using this new method it was possible to control the precision within 10% when considering the light spot received by the four-quadrant detector, and computation time was reduced compared with the traditional method of separately analysing the temperature field of the front dome and rear optical lens using FEA. Thus, the method can effectively increase the efficiency of parameter analysis and computation in an airborne optical system, facilitating the systematic, effective and integrated thermal analysis of airborne optical systems for navigation guidance and control.

  1. Navigation errors encountered using weather-mapping radar for helicopter IFR guidance to oil rigs

    Science.gov (United States)

    Phillips, J. D.; Bull, J. S.; Hegarty, D. M.; Dugan, D. C.

    1980-01-01

    In 1978 a joint NASA-FAA helicopter flight test was conducted to examine the use of weather-mapping radar for IFR guidance during landing approaches to oil rig helipads. The following navigation errors were measured: total system error, radar-range error, radar-bearing error, and flight technical error. Three problem areas were identified: (1) operational problems leading to pilot blunders, (2) poor navigation to the downwind final approach point, and (3) pure homing on final approach. Analysis of these problem areas suggests improvement in the radar equipment, approach procedure, and pilot training, and gives valuable insight into the development of future navigation aids to serve the off-shore oil industry.

  2. European Universities' Guidance on Research Integrity and Misconduct.

    Science.gov (United States)

    Aubert Bonn, Noémie; Godecharle, Simon; Dierickx, Kris

    2017-02-01

    Research integrity is imperative to good science. Nonetheless, many countries and institutions develop their own integrity guidance, thereby risking incompatibilities with guidance of collaborating institutions. We retrieved guidance for academic integrity and misconduct of 18 universities from 10 European countries and investigated accessibility, general content, principles endorsed, and definitions of misconduct. Accessibility and content differ substantially between institutions. There are general trends of common principles of integrity and definitions of misconduct, yet differences remain. Parallel with previous research, we distinguish different approaches in integrity guidance; one emphasizes broad values of integrity, and the other details negative behaviors of misconduct. We propose that a balance between both approaches is necessary to preserve trust, meaning, and realism of guidance on research integrity.

  3. Vehicle health management for guidance, navigation and control systems

    Science.gov (United States)

    Radke, Kathleen; Frazzini, Ron; Bursch, Paul; Wald, Jerry; Brown, Don

    1993-01-01

    The objective of the program was to architect a vehicle health management (VHM) system for space systems avionics that assures system readiness for launch vehicles and for space-based dormant vehicles. The platforms which were studied and considered for application of VHM for guidance, navigation and control (GN&C) included the Advanced Manned Launch System (AMLS), the Horizontal Landing-20/Personnel Launch System (HL-20/PLS), the Assured Crew Return Vehicle (ACRV) and the Extended Duration Orbiter (EDO). This set was selected because dormancy and/or availability requirements are driving the designs of these future systems.

  4. Guidance, navigation, and control subsystem equipment selection algorithm using expert system methods

    Science.gov (United States)

    Allen, Cheryl L.

    1991-01-01

    Enhanced engineering tools can be obtained through the integration of expert system methodologies and existing design software. The application of these methodologies to the spacecraft design and cost model (SDCM) software provides an improved technique for the selection of hardware for unmanned spacecraft subsystem design. The knowledge engineering system (KES) expert system development tool was used to implement a smarter equipment section algorithm than that which is currently achievable through the use of a standard data base system. The guidance, navigation, and control subsystems of the SDCM software was chosen as the initial subsystem for implementation. The portions of the SDCM code which compute the selection criteria and constraints remain intact, and the expert system equipment selection algorithm is embedded within this existing code. The architecture of this new methodology is described and its implementation is reported. The project background and a brief overview of the expert system is described, and once the details of the design are characterized, an example of its implementation is demonstrated.

  5. Analysis of the Effects of Thermal Environment on Optical Systems for Navigation Guidance and Control in Supersonic Aircraft Based on Empirical Equations

    Directory of Open Access Journals (Sweden)

    Xuemin Cheng

    2016-10-01

    Full Text Available The thermal environment is an important factor in the design of optical systems. This study investigated the thermal analysis technology of optical systems for navigation guidance and control in supersonic aircraft by developing empirical equations for the front temperature gradient and rear thermal diffusion distance, and for basic factors such as flying parameters and the structure of the optical system. Finite element analysis (FEA was used to study the relationship between flying and front dome parameters and the system temperature field. Systematic deduction was then conducted based on the effects of the temperature field on the physical geometry and ray tracing performance of the front dome and rear optical lenses, by deriving the relational expressions between the system temperature field and the spot size and positioning precision of the rear optical lens. The optical systems used for navigation guidance and control in supersonic aircraft when the flight speed is in the range of 1–5 Ma were analysed using the derived equations. Using this new method it was possible to control the precision within 10% when considering the light spot received by the four-quadrant detector, and computation time was reduced compared with the traditional method of separately analysing the temperature field of the front dome and rear optical lens using FEA. Thus, the method can effectively increase the efficiency of parameter analysis and computation in an airborne optical system, facilitating the systematic, effective and integrated thermal analysis of airborne optical systems for navigation guidance and control.

  6. Heading-vector navigation based on head-direction cells and path integration.

    Science.gov (United States)

    Kubie, John L; Fenton, André A

    2009-05-01

    Insect navigation is guided by heading vectors that are computed by path integration. Mammalian navigation models, on the other hand, are typically based on map-like place representations provided by hippocampal place cells. Such models compute optimal routes as a continuous series of locations that connect the current location to a goal. We propose a "heading-vector" model in which head-direction cells or their derivatives serve both as key elements in constructing the optimal route and as the straight-line guidance during route execution. The model is based on a memory structure termed the "shortcut matrix," which is constructed during the initial exploration of an environment when a set of shortcut vectors between sequential pairs of visited waypoint locations is stored. A mechanism is proposed for calculating and storing these vectors that relies on a hypothesized cell type termed an "accumulating head-direction cell." Following exploration, shortcut vectors connecting all pairs of waypoint locations are computed by vector arithmetic and stored in the shortcut matrix. On re-entry, when local view or place representations query the shortcut matrix with a current waypoint and goal, a shortcut trajectory is retrieved. Since the trajectory direction is in head-direction compass coordinates, navigation is accomplished by tracking the firing of head-direction cells that are tuned to the heading angle. Section 1 of the manuscript describes the properties of accumulating head-direction cells. It then shows how accumulating head-direction cells can store local vectors and perform vector arithmetic to perform path-integration-based homing. Section 2 describes the construction and use of the shortcut matrix for computing direct paths between any pair of locations that have been registered in the shortcut matrix. In the discussion, we analyze the advantages of heading-based navigation over map-based navigation. Finally, we survey behavioral evidence that nonhippocampal

  7. Integrated navigation method of a marine strapdown inertial navigation system using a star sensor

    International Nuclear Information System (INIS)

    Wang, Qiuying; Diao, Ming; Gao, Wei; Zhu, Minghong; Xiao, Shu

    2015-01-01

    This paper presents an integrated navigation method of the strapdown inertial navigation system (SINS) using a star sensor. According to the principle of SINS, its own navigation information contains an error that increases with time. Hence, the inertial attitude matrix from the star sensor is introduced as the reference information to correct the SINS increases error. For the integrated navigation method, the vehicle’s attitude can be obtained in two ways: one is calculated from SINS; the other, which we have called star sensor attitude, is obtained as the product between the SINS position and the inertial attitude matrix from the star sensor. Therefore, the SINS position error is introduced in the star sensor attitude error. Based on the characteristics of star sensor attitude error and the mathematical derivation, the SINS navigation errors can be obtained by the coupling calculation between the SINS attitude and the star sensor attitude. Unlike several current techniques, the navigation process of this method is non-radiating and invulnerable to jamming. The effectiveness of this approach was demonstrated by simulation and experimental study. The results show that this integrated navigation method can estimate the attitude error and the position error of SINS. Therefore, the SINS navigation accuracy is improved. (paper)

  8. 3rd CEAS Specialist Conference on Guidance, Navigation and Control

    CERN Document Server

    Drouin, Antoine; Roos, Clément

    2015-01-01

    The two first CEAS (Council of European Aerospace Societies) Specialist Conferences on Guidance, Navigation and Control (CEAS EuroGNC) were held in Munich, Germany in 2011 and in Delft, The Netherlands in 2013. ONERA The French Aerospace Lab, ISAE (Institut Supérieur de l’Aéronautique et de l’Espace) and ENAC (Ecole Nationale de l’Aviation Civile) accepted the challenge of jointly organizing the 3rd edition. The conference aims at promoting new advances in aerospace GNC theory and technologies for enhancing safety, survivability, efficiency, performance, autonomy and intelligence of aerospace systems. It represents a unique forum for communication and information exchange between specialists in the fields of GNC systems design and operation, including air traffic management. This book contains the forty best papers and gives an interesting snapshot of the latest advances over the following topics: l  Control theory, analysis, and design l  Novel navigation, estimation, and tracking methods l  Aircr...

  9. Navigation and flight director guidance for the NASA/FAA helicopter MLS curved approach flight test program

    Science.gov (United States)

    Phatak, A. V.; Lee, M. G.

    1985-01-01

    The navigation and flight director guidance systems implemented in the NASA/FAA helicopter microwave landing system (MLS) curved approach flight test program is described. Flight test were conducted at the U.S. Navy's Crows Landing facility, using the NASA Ames UH-lH helicopter equipped with the V/STOLAND avionics system. The purpose of these tests was to investigate the feasibility of flying complex, curved and descending approaches to a landing using MLS flight director guidance. A description of the navigation aids used, the avionics system, cockpit instrumentation and on-board navigation equipment used for the flight test is provided. Three generic reference flight paths were developed and flown during the test. They were as follows: U-Turn, S-turn and Straight-In flight profiles. These profiles and their geometries are described in detail. A 3-cue flight director was implemented on the helicopter. A description of the formulation and implementation of the flight director laws is also presented. Performance data and analysis is presented for one pilot conducting the flight director approaches.

  10. Terminal area automatic navigation, guidance, and control research using the Microwave Landing System (MLS). Part 2: RNAV/MLS transition problems for aircraft

    Science.gov (United States)

    Pines, S.

    1982-01-01

    The problems in navigation and guidance encountered by aircraft in the initial transition period in changing from distance measuring equipment, VORTAC, and barometric instruments to the more precise microwave landing system data type navaids in the terminal area are investigated. The effects of the resulting discontinuities on the estimates of position and velocity for both optimal (Kalman type navigation schemes) and fixed gain (complementary type) navigation filters, and the effects of the errors in cross track, track angle, and altitude on the guidance equation and control commands during the critical landing phase are discussed. A method is presented to remove the discontinuities from the navigation loop and to reconstruct an RNAV path designed to land the aircraft with minimal turns and altitude changes.

  11. Vision/INS Integrated Navigation System for Poor Vision Navigation Environments

    Directory of Open Access Journals (Sweden)

    Youngsun Kim

    2016-10-01

    Full Text Available In order to improve the performance of an inertial navigation system, many aiding sensors can be used. Among these aiding sensors, a vision sensor is of particular note due to its benefits in terms of weight, cost, and power consumption. This paper proposes an inertial and vision integrated navigation method for poor vision navigation environments. The proposed method uses focal plane measurements of landmarks in order to provide position, velocity and attitude outputs even when the number of landmarks on the focal plane is not enough for navigation. In order to verify the proposed method, computer simulations and van tests are carried out. The results show that the proposed method gives accurate and reliable position, velocity and attitude outputs when the number of landmarks is insufficient.

  12. Terminal attack trajectories of peregrine falcons are described by the proportional navigation guidance law of missiles.

    Science.gov (United States)

    Brighton, Caroline H; Thomas, Adrian L R; Taylor, Graham K

    2017-12-19

    The ability to intercept uncooperative targets is key to many diverse flight behaviors, from courtship to predation. Previous research has looked for simple geometric rules describing the attack trajectories of animals, but the underlying feedback laws have remained obscure. Here, we use GPS loggers and onboard video cameras to study peregrine falcons, Falco peregrinus , attacking stationary targets, maneuvering targets, and live prey. We show that the terminal attack trajectories of peregrines are not described by any simple geometric rule as previously claimed, and instead use system identification techniques to fit a phenomenological model of the dynamical system generating the observed trajectories. We find that these trajectories are best-and exceedingly well-modeled by the proportional navigation (PN) guidance law used by most guided missiles. Under this guidance law, turning is commanded at a rate proportional to the angular rate of the line-of-sight between the attacker and its target, with a constant of proportionality (i.e., feedback gain) called the navigation constant ( N ). Whereas most guided missiles use navigation constants falling on the interval 3 ≤ N ≤ 5, peregrine attack trajectories are best fitted by lower navigation constants (median N law could find use in small visually guided drones designed to remove other drones from protected airspace. Copyright © 2017 the Author(s). Published by PNAS.

  13. Measuring Integrated Socioemotional Guidance at School: Factor Structure and Reliability of the Socioemotional Guidance Questionnaire (SEG-Q)

    Science.gov (United States)

    Jacobs, Karen; Struyf, Elke

    2013-01-01

    Socioemotional guidance of students has recently become an integral part of education, however no instrument exists to measure integrated socioemotional guidance. This study therefore examines the factor structure and reliability of the Socioemotional Guidance Questionnaire. Psychometric properties of the Socioemotional Guidance Questionnaire and…

  14. Terminal area automatic navigation, guidance, and control 1: Automatic rollout, turnoff, and taxis

    Science.gov (United States)

    Pines, S.

    1981-01-01

    A study developed for the TCV B-737, designed to apply existing navigation aids plus magnetic leader cable signals and develop breaking and reverse thrust guidance laws to provide for rapid automated rollout, turnoff, and taxi to reduce runway occupation time for a wide variety of landing conditions for conventional commercial-type aircraft, is described. Closed loop guidance laws for braking and reverse thrust are derived for rollout, turnoff, and taxi, as functions of the landing speed, the desired taxi speed and the distance to go. Brake limitations for wet runway conditions and reverse thrust limitations are taken into account to provide decision rules to avoid tire skid and to choose an alternate turnoff point, farther down the runway, to accommodate extreme landing conditions.

  15. A Modified Proportional Navigation Guidance for Accurate Target Hitting

    Directory of Open Access Journals (Sweden)

    A. Moharampour

    2010-03-01

    First, the pure proportional navigation guidance (PPNG in 3-dimensional state is explained in a new point of view. The main idea is based on the distinction between angular rate vector and rotation vector conceptions. The current innovation is based on selection of line of sight (LOS coordinates. A comparison between two available choices for LOS coordinates system is proposed. An improvement is made by adding two additional terms. First term includes a cross range compensator which is used to provide and enhance path observability, and obtain convergent estimates of state variables. The second term is new concept lead bias term, which has been calculated by assuming an equivalent acceleration along the target longitudinal axis. Simulation results indicate that the lead bias term properly provides terminal conditions for accurate target interception.

  16. Project Management Using Modern Guidance, Navigation and Control Theory

    Science.gov (United States)

    Hill, Terry R.

    2011-01-01

    Implementing guidance, navigation, and control (GN&C) theory principles and applying them to the human element of project management and control is not a new concept. As both the literature on the subject and the real-world applications are neither readily available nor comprehensive with regard to how such principles might be applied, this paper has been written to educate the project manager on the "laws of physics" of his or her project (not to teach a GN&C engineer how to become a project manager) and to provide an intuitive, mathematical explanation as to the control and behavior of projects. This paper will also address how the fundamental principles of modern GN&C were applied to the National Aeronautics and Space Administration's (NASA) Constellation Program (CxP) space suit project, ensuring the project was managed within cost, schedule, and budget. A project that is akin to a physical system can be modeled and managed using the same over arching principles of GN&C that would be used if that project were a complex vehicle, a complex system(s), or complex software with time-varying processes (at times nonlinear) containing multiple data inputs of varying accuracy and a range of operating points. The classic GN&C theory approach could thus be applied to small, well-defined projects; yet when working with larger, multiyear projects necessitating multiple organizational structures, numerous external influences, and a multitude of diverse resources, modern GN&C principles are required to model and manage the project. The fundamental principles of a GN&C system incorporate these basic concepts: State, Behavior, Feedback Control, Navigation, Guidance and Planning Logic systems. The State of a system defines the aspects of the system that can change over time; e.g., position, velocity, acceleration, coordinate-based attitude, and temperature, etc. The Behavior of the system focuses more on what changes are possible within the system; this is denoted in the state

  17. Navigation integrity monitoring and obstacle detection for enhanced-vision systems

    Science.gov (United States)

    Korn, Bernd; Doehler, Hans-Ullrich; Hecker, Peter

    2001-08-01

    Typically, Enhanced Vision (EV) systems consist of two main parts, sensor vision and synthetic vision. Synthetic vision usually generates a virtual out-the-window view using databases and accurate navigation data, e. g. provided by differential GPS (DGPS). The reliability of the synthetic vision highly depends on both, the accuracy of the used database and the integrity of the navigation data. But especially in GPS based systems, the integrity of the navigation can't be guaranteed. Furthermore, only objects that are stored in the database can be displayed to the pilot. Consequently, unexpected obstacles are invisible and this might cause severe problems. Therefore, additional information has to be extracted from sensor data to overcome these problems. In particular, the sensor data analysis has to identify obstacles and has to monitor the integrity of databases and navigation. Furthermore, if a lack of integrity arises, navigation data, e.g. the relative position of runway and aircraft, has to be extracted directly from the sensor data. The main contribution of this paper is about the realization of these three sensor data analysis tasks within our EV system, which uses the HiVision 35 GHz MMW radar of EADS, Ulm as the primary EV sensor. For the integrity monitoring, objects extracted from radar images are registered with both database objects and objects (e. g. other aircrafts) transmitted via data link. This results in a classification into known and unknown radar image objects and consequently, in a validation of the integrity of database and navigation. Furthermore, special runway structures are searched for in the radar image where they should appear. The outcome of this runway check contributes to the integrity analysis, too. Concurrent to this investigation a radar image based navigation is performed without using neither precision navigation nor detailed database information to determine the aircraft's position relative to the runway. The performance of our

  18. Integration of Environment Sensing and Control Functions for Robust Rotorcraft UAV (RUAV) Guidance

    Science.gov (United States)

    Dadkhah Tehrani, Navid

    Unmanned Air Vehicles (UAVs) have started supplanting manned aircraft in a broad range of tasks. Vehicles such as miniature rotorcrafts with broad maneuvering range and small size can enter remote locations that are hard to reach using other air and ground vehicles. Developing a guidance system which enables a Rotorcraft UAV (RUAV) to perform such tasks involves combing key elements from robotics motion planning, control system design, trajectory optimization as well as dynamics modeling. The focus of this thesis is to integrate a guidance system for a small-scale rotorcraft to enable a high level of performance and situational awareness. We cover large aspects of the system integration including modeling, control system design, environment sensing as well as motion planning in the presence of uncertainty. The system integration in this thesis is performed around a Blade-CX2 miniature coaxial helicopter. The first part of the thesis focuses on the development of the parameterized model for the Blade-CX2 helicopter with an emphasis on the coaxial rotor configuration. The model explicitly accounts for the dynamics of lower rotor and uses an implicit lumped parameter model for the upper rotor and stabilizer-bar. The parameterized model was identified using frequency domain system identification. In the second part of the thesis, we use the identified model to design a control law for the Blade-CX2 helicopter. The control augmentation for the Blade-CX2 helicopter was based on a nested attitude-velocity loop control architecture and was designed following classical loop-shaping and dynamic inversion techniques. A path following layer wrapped around the velocity control system enables the rotorcraft to follow reference trajectories specified by a sequence of waypoints and velocity vectors. Such reference paths are common in autonomous guidance systems. Finally, the third part of the thesis addresses the problem of autonomous navigation through a partially known or

  19. Hybrid extended particle filter (HEPF) for integrated inertial navigation and global positioning systems

    International Nuclear Information System (INIS)

    Aggarwal, Priyanka; Syed, Zainab; El-Sheimy, Naser

    2009-01-01

    Navigation includes the integration of methodologies and systems for estimating time-varying position, velocity and attitude of moving objects. Navigation incorporating the integrated inertial navigation system (INS) and global positioning system (GPS) generally requires extensive evaluations of nonlinear equations involving double integration. Currently, integrated navigation systems are commonly implemented using the extended Kalman filter (EKF). The EKF assumes a linearized process, measurement models and Gaussian noise distributions. These assumptions are unrealistic for highly nonlinear systems like land vehicle navigation and may cause filter divergence. A particle filter (PF) is developed to enhance integrated INS/GPS system performance as it can easily deal with nonlinearity and non-Gaussian noises. In this paper, a hybrid extended particle filter (HEPF) is developed as an alternative to the well-known EKF to achieve better navigation data accuracy for low-cost microelectromechanical system sensors. The results show that the HEPF performs better than the EKF during GPS outages, especially when simulated outages are located in periods with high vehicle dynamics

  20. A Neural Path Integration Mechanism for Adaptive Vector Navigation in Autonomous Agents

    DEFF Research Database (Denmark)

    Goldschmidt, Dennis; Dasgupta, Sakyasingha; Wörgötter, Florentin

    2015-01-01

    Animals show remarkable capabilities in navigating their habitat in a fully autonomous and energy-efficient way. In many species, these capabilities rely on a process called path integration, which enables them to estimate their current location and to find their way back home after long-distance...... of autonomous agent navigation, but it also reproduces various aspects of animal navigation. Finally, we discuss how the proposed path integration mechanism may be used as a scaffold for spatial learning in terms of vector navigation.......Animals show remarkable capabilities in navigating their habitat in a fully autonomous and energy-efficient way. In many species, these capabilities rely on a process called path integration, which enables them to estimate their current location and to find their way back home after long...

  1. Mars Atmospheric Entry Integrated Navigation with Partial Intermittent Measurements

    Directory of Open Access Journals (Sweden)

    Tai-shan Lou

    2017-01-01

    Full Text Available Signal degradation suffered by the vehicle is a combination brownout and blackout during Mars atmospheric entry. The communications brownout means that signal fades and blackout means that the signal is lost completely. The communications brownout and blackout periods are analyzed and predicted with an altitude and velocity profiles. In the brownout period, the range measurements between the vehicle and the orbiters are modeled as intermittent measurements with the radio signal arrival probabilities, which are distributed as a Rayleigh distribution of the electron number density around the entry vehicle. A new integrated navigation strategy during the Mars atmospheric entry phase is proposed to consider the probabilities of the radio measurements in the communications brownout and blackout periods under the IMU/beacon scenario based on the information filter with intermittent measurements. Numerical navigation simulations are designed to show the performance of the proposed navigation strategy under the integrated navigation scenario.

  2. Guidance and control, 1993; Annual Rocky Mountain Guidance and Control Conference, 16th, Keystone, CO, Feb. 6-10, 1993

    Science.gov (United States)

    Culp, Robert D.; Bickley, George

    Papers from the sixteenth annual American Astronautical Society Rocky Mountain Guidance and Control Conference are presented. The topics covered include the following: advances in guidance, navigation, and control; control system videos; guidance, navigation and control embedded flight control systems; recent experiences; guidance and control storyboard displays; and applications of modern control, featuring the Hubble Space Telescope (HST) performance enhancement study. For individual titles, see A95-80390 through A95-80436.

  3. Indoor integrated navigation and synchronous data acquisition method for Android smartphone

    Science.gov (United States)

    Hu, Chunsheng; Wei, Wenjian; Qin, Shiqiao; Wang, Xingshu; Habib, Ayman; Wang, Ruisheng

    2015-08-01

    Smartphones are widely used at present. Most smartphones have cameras and kinds of sensors, such as gyroscope, accelerometer and magnet meter. Indoor navigation based on smartphone is very important and valuable. According to the features of the smartphone and indoor navigation, a new indoor integrated navigation method is proposed, which uses MEMS (Micro-Electro-Mechanical Systems) IMU (Inertial Measurement Unit), camera and magnet meter of smartphone. The proposed navigation method mainly involves data acquisition, camera calibration, image measurement, IMU calibration, initial alignment, strapdown integral, zero velocity update and integrated navigation. Synchronous data acquisition of the sensors (gyroscope, accelerometer and magnet meter) and the camera is the base of the indoor navigation on the smartphone. A camera data acquisition method is introduced, which uses the camera class of Android to record images and time of smartphone camera. Two kinds of sensor data acquisition methods are introduced and compared. The first method records sensor data and time with the SensorManager of Android. The second method realizes open, close, data receiving and saving functions in C language, and calls the sensor functions in Java language with JNI interface. A data acquisition software is developed with JDK (Java Development Kit), Android ADT (Android Development Tools) and NDK (Native Development Kit). The software can record camera data, sensor data and time at the same time. Data acquisition experiments have been done with the developed software and Sumsang Note 2 smartphone. The experimental results show that the first method of sensor data acquisition is convenient but lost the sensor data sometimes, the second method is much better in real-time performance and much less in data losing. A checkerboard image is recorded, and the corner points of the checkerboard are detected with the Harris method. The sensor data of gyroscope, accelerometer and magnet meter have

  4. HOLISTIC VISION: INTEGRATIVE APPROACH IN GUIDANCE AND COUNSELING SERVICES

    Directory of Open Access Journals (Sweden)

    Ade Hidayat

    2016-06-01

    Full Text Available Abstract: The philosophical issues in Guidance and Counseling especially in epistemological discourse have made paradigmatic friction that pointed by some issues from therapeutic-clinical to comprehensive way with preventive development prespective approach. It was also caused by the wider friction where quantum physic has remove classic Newtonian one, then the influence has generally removed another disciplines, where Guidance and Counseling in one of them. Through the comprehensive paradigm, Guidance dan Counseling need to take prepare the expert in order to capable to develop integrated and comprehensive thinking awareness. It means the Guidance and Counseling holistic vision is urged. Through the holistic vision, all of the competency of student is noticed integrally, such as intellectual, emotional, social, physical, artistic, creativity, ecological awareness, and spiritual competencies.Keywords: Ecoliteracy, Holictic Vision, Guidance and Counseling of Comprehensive.

  5. FPGA-based real-time embedded system for RISS/GPS integrated navigation.

    Science.gov (United States)

    Abdelfatah, Walid Farid; Georgy, Jacques; Iqbal, Umar; Noureldin, Aboelmagd

    2012-01-01

    Navigation algorithms integrating measurements from multi-sensor systems overcome the problems that arise from using GPS navigation systems in standalone mode. Algorithms which integrate the data from 2D low-cost reduced inertial sensor system (RISS), consisting of a gyroscope and an odometer or wheel encoders, along with a GPS receiver via a Kalman filter has proved to be worthy in providing a consistent and more reliable navigation solution compared to standalone GPS receivers. It has been also shown to be beneficial, especially in GPS-denied environments such as urban canyons and tunnels. The main objective of this paper is to narrow the idea-to-implementation gap that follows the algorithm development by realizing a low-cost real-time embedded navigation system capable of computing the data-fused positioning solution. The role of the developed system is to synchronize the measurements from the three sensors, relative to the pulse per second signal generated from the GPS, after which the navigation algorithm is applied to the synchronized measurements to compute the navigation solution in real-time. Employing a customizable soft-core processor on an FPGA in the kernel of the navigation system, provided the flexibility for communicating with the various sensors and the computation capability required by the Kalman filter integration algorithm.

  6. 2nd CEAS Specialist Conference on Guidance, Navigation and Control

    CERN Document Server

    Mulder, Bob; Choukroun, Daniel; Kampen, Erik-Jan; Visser, Coen; Looye, Gertjan

    2013-01-01

    Following the successful 1st CEAS (Council of European Aerospace Societies) Specialist Conference on Guidance, Navigation and Control (CEAS EuroGNC) held in Munich, Germany in 2011, Delft University of Technology happily accepted the invitation of organizing the 2nd  CEAS EuroGNC in Delft, The Netherlands in 2013. The goal of the conference is to promote new advances in aerospace GNC theory and technologies for enhancing safety, survivability, efficiency, performance, autonomy and intelligence of aerospace systems using on-board sensing, computing and systems. A great push for new developments in GNC are the ever higher safety and sustainability requirements in aviation. Impressive progress was made in new research fields such as sensor and actuator fault detection and diagnosis, reconfigurable and fault tolerant flight control, online safe flight envelop prediction and protection, online global aerodynamic model identification, online global optimization and flight upset recovery. All of these challenges de...

  7. Towards a new approach to model guidance laws

    International Nuclear Information System (INIS)

    Borne, P.; Duflos, E.; Vanheeghe, P.

    1994-01-01

    Proportional navigation laws have been widely used and studied. Nevertheless very few publications explain rigorously the origin of all these laws. For researchers who are starting to work on guidance laws, a feeling of confusion can result. For others, this lack of explanation can be, for example, the source of the difficulties to make the true proportional navigation become equivalent to the pure proportional navigation. The authors propose here a way to model guidance laws in order to fill this lack of explanation. The first consequence is a better exploration of the kinematic behaviors arising during the guidance process. The second consequence is the definition of a new 3D guidance law which can be seen as a generalization of the true proportional navigation. Moreover, this generalization allow this last law to become equivalent to the pure proportional navigation in terms of initial conditions which allow the object to reach its target

  8. Integrated INS/GPS Navigation from a Popular Perspective

    Science.gov (United States)

    Omerbashich, Mensur

    2002-01-01

    Inertial navigation, blended with other navigation aids, Global Positioning System (GPS) in particular, has gained significance due to enhanced navigation and inertial reference performance and dissimilarity for fault tolerance and anti-jamming. Relatively new concepts based upon using Differential GPS (DGPS) blended with Inertial (and visual) Navigation Sensors (INS) offer the possibility of low cost, autonomous aircraft landing. The FAA has decided to implement the system in a sophisticated form as a new standard navigation tool during this decade. There have been a number of new inertial sensor concepts in the recent past that emphasize increased accuracy of INS/GPS versus INS and reliability of navigation, as well as lower size and weight, and higher power, fault tolerance, and long life. The principles of GPS are not discussed; rather the attention is directed towards general concepts and comparative advantages. A short introduction to the problems faced in kinematics is presented. The intention is to relate the basic principles of kinematics to probably the most used navigation method in the future-INS/GPS. An example of the airborne INS is presented, with emphasis on how it works. The discussion of the error types and sources in navigation, and of the role of filters in optimal estimation of the errors then follows. The main question this paper is trying to answer is 'What are the benefits of the integration of INS and GPS and how is this, navigation concept of the future achieved in reality?' The main goal is to communicate the idea about what stands behind a modern navigation method.

  9. Real-time fluoroscopic needle guidance in the interventional radiology suite using navigational software for percutaneous bone biopsies in children

    Energy Technology Data Exchange (ETDEWEB)

    Shellikeri, Sphoorti; Srinivasan, Abhay; Krishnamurthy, Ganesh; Vatsky, Seth; Zhu, Xiaowei; Keller, Marc S.; Cahill, Anne Marie [The Children' s Hospital of Philadelphia, Department of Radiology, Philadelphia, PA (United States); Setser, Randolph M. [Siemens Medical Solutions USA, Inc., Hoffman Estates, IL (United States); Hwang, Tiffany J. [University of Southern California, Keck School of Medicine, Los Angeles, CA (United States); Girard, Erin [Siemens Medical Solutions USA, Inc., Princeton, NJ (United States)

    2017-07-15

    Navigational software provides real-time fluoroscopic needle guidance for percutaneous procedures in the Interventional Radiology (IR) suite. We describe our experience with navigational software for pediatric percutaneous bone biopsies in the IR suite and compare technical success, diagnostic accuracy, radiation dose and procedure time with that of CT-guided biopsies. Pediatric bone biopsies performed using navigational software (Syngo iGuide, Siemens Healthcare) from 2011 to 2016 were prospectively included and anatomically matched CT-guided bone biopsies from 2008 to 2016 were retrospectively reviewed with institutional review board approval. C-arm CT protocols used for navigational software-assisted cases included institution-developed low-dose (0.1/0.17 μGy/projection), regular-dose (0.36 μGy/projection), or a combination of low-dose/regular-dose protocols. Estimated effective radiation dose and procedure times were compared between software-assisted and CT-guided biopsies. Twenty-six patients (15 male; mean age: 10 years) underwent software-assisted biopsies (15 pelvic, 7 lumbar and 4 lower extremity) and 33 patients (13 male; mean age: 9 years) underwent CT-guided biopsies (22 pelvic, 7 lumbar and 4 lower extremity). Both modality biopsies resulted in a 100% technical success rate. Twenty-five of 26 (96%) software-assisted and 29/33 (88%) CT-guided biopsies were diagnostic. Overall, the effective radiation dose was significantly lower in software-assisted than CT-guided cases (3.0±3.4 vs. 6.6±7.7 mSv, P=0.02). The effective dose difference was most dramatic in software-assisted cases using low-dose C-arm CT (1.2±1.8 vs. 6.6±7.7 mSv, P=0.001) or combined low-dose/regular-dose C-arm CT (1.9±2.4 vs. 6.6±7.7 mSv, P=0.04), whereas effective dose was comparable in software-assisted cases using regular-dose C-arm CT (6.0±3.5 vs. 6.6±7.7 mSv, P=0.7). Mean procedure time was significantly lower for software-assisted cases (91±54 vs. 141±68 min, P=0

  10. Fundamentals of Inertial Navigation, Satellite-based Positioning and their Integration

    CERN Document Server

    Noureldin, Aboelmagd; Georgy, Jacques

    2013-01-01

    Fundamentals of Inertial Navigation, Satellite-based Positioning and their Integration is an introduction to the field of Integrated Navigation Systems. It serves as an excellent reference for working engineers as well as textbook for beginners and students new to the area. The book is easy to read and understand with minimum background knowledge. The authors explain the derivations in great detail. The intermediate steps are thoroughly explained so that a beginner can easily follow the material. The book shows a step-by-step implementation of navigation algorithms and provides all the necessary details. It provides detailed illustrations for an easy comprehension. The book also demonstrates real field experiments and in-vehicle road test results with professional discussions and analysis. This work is unique in discussing the different INS/GPS integration schemes in an easy to understand and straightforward way. Those schemes include loosely vs tightly coupled, open loop vs closed loop, and many more.

  11. INTEGRITY ANALYSIS OF REAL-TIME PPP TECHNIQUE WITH IGS-RTS SERVICE FOR MARITIME NAVIGATION

    Directory of Open Access Journals (Sweden)

    M. El-Diasty

    2017-10-01

    Full Text Available Open sea and inland waterways are the most widely used mode for transporting goods worldwide. It is the International Maritime Organization (IMO that defines the requirements for position fixing equipment for a worldwide radio-navigation system, in terms of accuracy, integrity, continuity, availability and coverage for the various phases of navigation. Satellite positioning systems can contribute to meet these requirements, as well as optimize marine transportation. Marine navigation usually consists of three major phases identified as Ocean/Coastal/Port approach/Inland waterway, in port navigation and automatic docking with alert limit ranges from 25 m to 0.25 m. GPS positioning is widely used for many applications and is currently recognized by IMO for a future maritime navigation. With the advancement in autonomous GPS positioning techniques such as Precise Point Positioning (PPP and with the advent of new real-time GNSS correction services such as IGS-Real-Time-Service (RTS, it is necessary to investigate the integrity of the PPP-based positioning technique along with IGS-RTS service in terms of availability and reliability for safe navigation in maritime application. This paper monitors the integrity of an autonomous real-time PPP-based GPS positioning system using the IGS real-time service (RTS for maritime applications that require minimum availability of integrity of 99.8 % to fulfil the IMO integrity standards. To examine the integrity of the real-time IGS-RTS PPP-based technique for maritime applications, kinematic data from a dual frequency GPS receiver is collected onboard a vessel and investigated with the real-time IGS-RTS PPP-based GPS positioning technique. It is shown that the availability of integrity of the real-time IGS-RTS PPP-based GPS solution is 100 % for all navigation phases and therefore fulfil the IMO integrity standards (99.8 % availability immediately (after 1 second, after 2 minutes and after 42 minutes

  12. Integrity Analysis of Real-Time Ppp Technique with Igs-Rts Service for Maritime Navigation

    Science.gov (United States)

    El-Diasty, M.

    2017-10-01

    Open sea and inland waterways are the most widely used mode for transporting goods worldwide. It is the International Maritime Organization (IMO) that defines the requirements for position fixing equipment for a worldwide radio-navigation system, in terms of accuracy, integrity, continuity, availability and coverage for the various phases of navigation. Satellite positioning systems can contribute to meet these requirements, as well as optimize marine transportation. Marine navigation usually consists of three major phases identified as Ocean/Coastal/Port approach/Inland waterway, in port navigation and automatic docking with alert limit ranges from 25 m to 0.25 m. GPS positioning is widely used for many applications and is currently recognized by IMO for a future maritime navigation. With the advancement in autonomous GPS positioning techniques such as Precise Point Positioning (PPP) and with the advent of new real-time GNSS correction services such as IGS-Real-Time-Service (RTS), it is necessary to investigate the integrity of the PPP-based positioning technique along with IGS-RTS service in terms of availability and reliability for safe navigation in maritime application. This paper monitors the integrity of an autonomous real-time PPP-based GPS positioning system using the IGS real-time service (RTS) for maritime applications that require minimum availability of integrity of 99.8 % to fulfil the IMO integrity standards. To examine the integrity of the real-time IGS-RTS PPP-based technique for maritime applications, kinematic data from a dual frequency GPS receiver is collected onboard a vessel and investigated with the real-time IGS-RTS PPP-based GPS positioning technique. It is shown that the availability of integrity of the real-time IGS-RTS PPP-based GPS solution is 100 % for all navigation phases and therefore fulfil the IMO integrity standards (99.8 % availability) immediately (after 1 second), after 2 minutes and after 42 minutes of convergence

  13. Fuzzy Adaptive Cubature Kalman Filter for Integrated Navigation Systems.

    Science.gov (United States)

    Tseng, Chien-Hao; Lin, Sheng-Fuu; Jwo, Dah-Jing

    2016-07-26

    This paper presents a sensor fusion method based on the combination of cubature Kalman filter (CKF) and fuzzy logic adaptive system (FLAS) for the integrated navigation systems, such as the GPS/INS (Global Positioning System/inertial navigation system) integration. The third-degree spherical-radial cubature rule applied in the CKF has been employed to avoid the numerically instability in the system model. In processing navigation integration, the performance of nonlinear filter based estimation of the position and velocity states may severely degrade caused by modeling errors due to dynamics uncertainties of the vehicle. In order to resolve the shortcoming for selecting the process noise covariance through personal experience or numerical simulation, a scheme called the fuzzy adaptive cubature Kalman filter (FACKF) is presented by introducing the FLAS to adjust the weighting factor of the process noise covariance matrix. The FLAS is incorporated into the CKF framework as a mechanism for timely implementing the tuning of process noise covariance matrix based on the information of degree of divergence (DOD) parameter. The proposed FACKF algorithm shows promising accuracy improvement as compared to the extended Kalman filter (EKF), unscented Kalman filter (UKF), and CKF approaches.

  14. Fuzzy Adaptive Cubature Kalman Filter for Integrated Navigation Systems

    Directory of Open Access Journals (Sweden)

    Chien-Hao Tseng

    2016-07-01

    Full Text Available This paper presents a sensor fusion method based on the combination of cubature Kalman filter (CKF and fuzzy logic adaptive system (FLAS for the integrated navigation systems, such as the GPS/INS (Global Positioning System/inertial navigation system integration. The third-degree spherical-radial cubature rule applied in the CKF has been employed to avoid the numerically instability in the system model. In processing navigation integration, the performance of nonlinear filter based estimation of the position and velocity states may severely degrade caused by modeling errors due to dynamics uncertainties of the vehicle. In order to resolve the shortcoming for selecting the process noise covariance through personal experience or numerical simulation, a scheme called the fuzzy adaptive cubature Kalman filter (FACKF is presented by introducing the FLAS to adjust the weighting factor of the process noise covariance matrix. The FLAS is incorporated into the CKF framework as a mechanism for timely implementing the tuning of process noise covariance matrix based on the information of degree of divergence (DOD parameter. The proposed FACKF algorithm shows promising accuracy improvement as compared to the extended Kalman filter (EKF, unscented Kalman filter (UKF, and CKF approaches.

  15. Maximum Correntropy Unscented Kalman Filter for Ballistic Missile Navigation System based on SINS/CNS Deeply Integrated Mode.

    Science.gov (United States)

    Hou, Bowen; He, Zhangming; Li, Dong; Zhou, Haiyin; Wang, Jiongqi

    2018-05-27

    Strap-down inertial navigation system/celestial navigation system ( SINS/CNS) integrated navigation is a high precision navigation technique for ballistic missiles. The traditional navigation method has a divergence in the position error. A deeply integrated mode for SINS/CNS navigation system is proposed to improve the navigation accuracy of ballistic missile. The deeply integrated navigation principle is described and the observability of the navigation system is analyzed. The nonlinearity, as well as the large outliers and the Gaussian mixture noises, often exists during the actual navigation process, leading to the divergence phenomenon of the navigation filter. The new nonlinear Kalman filter on the basis of the maximum correntropy theory and unscented transformation, named the maximum correntropy unscented Kalman filter, is deduced, and the computational complexity is analyzed. The unscented transformation is used for restricting the nonlinearity of the system equation, and the maximum correntropy theory is used to deal with the non-Gaussian noises. Finally, numerical simulation illustrates the superiority of the proposed filter compared with the traditional unscented Kalman filter. The comparison results show that the large outliers and the influence of non-Gaussian noises for SINS/CNS deeply integrated navigation is significantly reduced through the proposed filter.

  16. INS integrated motion analysis for autonomous vehicle navigation

    Science.gov (United States)

    Roberts, Barry; Bazakos, Mike

    1991-01-01

    The use of inertial navigation system (INS) measurements to enhance the quality and robustness of motion analysis techniques used for obstacle detection is discussed with particular reference to autonomous vehicle navigation. The approach to obstacle detection used here employs motion analysis of imagery generated by a passive sensor. Motion analysis of imagery obtained during vehicle travel is used to generate range measurements to points within the field of view of the sensor, which can then be used to provide obstacle detection. Results obtained with an INS integrated motion analysis approach are reviewed.

  17. Maximum Correntropy Unscented Kalman Filter for Ballistic Missile Navigation System based on SINS/CNS Deeply Integrated Mode

    Directory of Open Access Journals (Sweden)

    Bowen Hou

    2018-05-01

    Full Text Available Strap-down inertial navigation system/celestial navigation system ( SINS/CNS integrated navigation is a high precision navigation technique for ballistic missiles. The traditional navigation method has a divergence in the position error. A deeply integrated mode for SINS/CNS navigation system is proposed to improve the navigation accuracy of ballistic missile. The deeply integrated navigation principle is described and the observability of the navigation system is analyzed. The nonlinearity, as well as the large outliers and the Gaussian mixture noises, often exists during the actual navigation process, leading to the divergence phenomenon of the navigation filter. The new nonlinear Kalman filter on the basis of the maximum correntropy theory and unscented transformation, named the maximum correntropy unscented Kalman filter, is deduced, and the computational complexity is analyzed. The unscented transformation is used for restricting the nonlinearity of the system equation, and the maximum correntropy theory is used to deal with the non-Gaussian noises. Finally, numerical simulation illustrates the superiority of the proposed filter compared with the traditional unscented Kalman filter. The comparison results show that the large outliers and the influence of non-Gaussian noises for SINS/CNS deeply integrated navigation is significantly reduced through the proposed filter.

  18. Monocular Camera/IMU/GNSS Integration for Ground Vehicle Navigation in Challenging GNSS Environments

    Directory of Open Access Journals (Sweden)

    Dennis Akos

    2012-03-01

    Full Text Available Low-cost MEMS-based IMUs, video cameras and portable GNSS devices are commercially available for automotive applications and some manufacturers have already integrated such facilities into their vehicle systems. GNSS provides positioning, navigation and timing solutions to users worldwide. However, signal attenuation, reflections or blockages may give rise to positioning difficulties. As opposed to GNSS, a generic IMU, which is independent of electromagnetic wave reception, can calculate a high-bandwidth navigation solution, however the output from a self-contained IMU accumulates errors over time. In addition, video cameras also possess great potential as alternate sensors in the navigation community, particularly in challenging GNSS environments and are becoming more common as options in vehicles. Aiming at taking advantage of these existing onboard technologies for ground vehicle navigation in challenging environments, this paper develops an integrated camera/IMU/GNSS system based on the extended Kalman filter (EKF. Our proposed integration architecture is examined using a live dataset collected in an operational traffic environment. The experimental results demonstrate that the proposed integrated system provides accurate estimations and potentially outperforms the tightly coupled GNSS/IMU integration in challenging environments with sparse GNSS observations.

  19. Monocular camera/IMU/GNSS integration for ground vehicle navigation in challenging GNSS environments.

    Science.gov (United States)

    Chu, Tianxing; Guo, Ningyan; Backén, Staffan; Akos, Dennis

    2012-01-01

    Low-cost MEMS-based IMUs, video cameras and portable GNSS devices are commercially available for automotive applications and some manufacturers have already integrated such facilities into their vehicle systems. GNSS provides positioning, navigation and timing solutions to users worldwide. However, signal attenuation, reflections or blockages may give rise to positioning difficulties. As opposed to GNSS, a generic IMU, which is independent of electromagnetic wave reception, can calculate a high-bandwidth navigation solution, however the output from a self-contained IMU accumulates errors over time. In addition, video cameras also possess great potential as alternate sensors in the navigation community, particularly in challenging GNSS environments and are becoming more common as options in vehicles. Aiming at taking advantage of these existing onboard technologies for ground vehicle navigation in challenging environments, this paper develops an integrated camera/IMU/GNSS system based on the extended Kalman filter (EKF). Our proposed integration architecture is examined using a live dataset collected in an operational traffic environment. The experimental results demonstrate that the proposed integrated system provides accurate estimations and potentially outperforms the tightly coupled GNSS/IMU integration in challenging environments with sparse GNSS observations.

  20. Monocular Camera/IMU/GNSS Integration for Ground Vehicle Navigation in Challenging GNSS Environments

    Science.gov (United States)

    Chu, Tianxing; Guo, Ningyan; Backén, Staffan; Akos, Dennis

    2012-01-01

    Low-cost MEMS-based IMUs, video cameras and portable GNSS devices are commercially available for automotive applications and some manufacturers have already integrated such facilities into their vehicle systems. GNSS provides positioning, navigation and timing solutions to users worldwide. However, signal attenuation, reflections or blockages may give rise to positioning difficulties. As opposed to GNSS, a generic IMU, which is independent of electromagnetic wave reception, can calculate a high-bandwidth navigation solution, however the output from a self-contained IMU accumulates errors over time. In addition, video cameras also possess great potential as alternate sensors in the navigation community, particularly in challenging GNSS environments and are becoming more common as options in vehicles. Aiming at taking advantage of these existing onboard technologies for ground vehicle navigation in challenging environments, this paper develops an integrated camera/IMU/GNSS system based on the extended Kalman filter (EKF). Our proposed integration architecture is examined using a live dataset collected in an operational traffic environment. The experimental results demonstrate that the proposed integrated system provides accurate estimations and potentially outperforms the tightly coupled GNSS/IMU integration in challenging environments with sparse GNSS observations. PMID:22736999

  1. Advanced approach for intraoperative MRI guidance and potential benefit for neurosurgical applications.

    Science.gov (United States)

    Busse, Harald; Schmitgen, Arno; Trantakis, Christos; Schober, Ralf; Kahn, Thomas; Moche, Michael

    2006-07-01

    To present an advanced approach for intraoperative image guidance in an open 0.5 T MRI and to evaluate its effectiveness for neurosurgical interventions by comparison with a dynamic scan-guided localization technique. The built-in scan guidance mode relied on successive interactive MRI scans. The additional advanced mode provided real-time navigation based on reformatted high-quality, intraoperatively acquired MR reference data, allowed multimodal image fusion, and used the successive scans of the built-in mode for quick verification of the position only. Analysis involved tumor resections and biopsies in either scan guidance (N = 36) or advanced mode (N = 59) by the same three neurosurgeons. Technical, surgical, and workflow aspects were compared. The image quality and hand-eye coordination of the advanced approach were improved. While the average extent of resection, neurologic outcome after functional MRI (fMRI) integration, and diagnostic yield appeared to be slightly better under advanced guidance, particularly for the main surgeon, statistical analysis revealed no significant differences. Resection times were comparable, while biopsies took around 30 minutes longer. The presented approach is safe and provides more detailed images and higher navigation speed at the expense of actuality. The surgical outcome achieved with advanced guidance is (at least) as good as that obtained with dynamic scan guidance. (c) 2006 Wiley-Liss, Inc.

  2. Fuzzy adaptive integration scheme for low-cost SINS/GPS navigation system

    Science.gov (United States)

    Nourmohammadi, Hossein; Keighobadi, Jafar

    2018-01-01

    Due to weak stand-alone accuracy as well as poor run-to-run stability of micro-electro mechanical system (MEMS)-based inertial sensors, special approaches are required to integrate low-cost strap-down inertial navigation system (SINS) with global positioning system (GPS), particularly in long-term applications. This paper aims to enhance long-term performance of conventional SINS/GPS navigation systems using a fuzzy adaptive integration scheme. The main concept behind the proposed adaptive integration is the good performance of attitude-heading reference system (AHRS) in low-accelerated motions and its degradation in maneuvered or accelerated motions. Depending on vehicle maneuvers, gravity-based attitude angles can be intelligently utilized to improve orientation estimation in the SINS. Knowledge-based fuzzy inference system is developed for decision-making between the AHRS and the SINS according to vehicle maneuvering conditions. Inertial measurements are the main input data of the fuzzy system to determine the maneuvering level during the vehicle motions. Accordingly, appropriate weighting coefficients are produced to combine the SINS/GPS and the AHRS, efficiently. The assessment of the proposed integrated navigation system is conducted via real data in airborne tests.

  3. Interactive navigation-guided ophthalmic plastic surgery: navigation enabling of telescopes and their use in endoscopic lacrimal surgeries

    Directory of Open Access Journals (Sweden)

    Ali MJ

    2016-11-01

    Full Text Available Mohammad Javed Ali,1 Swati Singh,1 Milind N Naik,1 Swathi Kaliki,2 Tarjani Vivek Dave1 1The Institute of Dacryology, 2The Operation Eyesight Universal Institute for Eye Cancer, L.V. Prasad Eye Institute, Hyderabad, India Purpose: The aims of this study were to report the preliminary experience of using telescopes, which were enabled for navigation guidance, and their utility in complex endoscopic lacrimal surgeries. Methods: Navigation enabling of the telescope was achieved by using the AxiEM™ malleable neuronavigation shunt stylet. Image-guided dacryolocalization was performed in five patients using the intraoperative image-guided StealthStation™ system in the electromagnetic mode. The “look ahead” protocol software was used to assist the surgeon in assessing the intraoperative geometric location of the endoscope and what lies ahead in real time. All patients underwent navigation-guided powered endoscopic dacryocystorhinostomy. The utility of uninterrupted navigation guidance throughout the surgery with the endoscope as the navigating tool was noted. Results: Intraoperative geometric localization of the lacrimal sac and the nasolacrimal duct could be easily deciphered. Constant orientation of the lacrimal drainage system and the peri-lacrimal anatomy was possible without the need for repeated point localizations throughout the surgery. The “look ahead” features could accurately alert the surgeon of anatomical structures that exists at 5, 10 and 15 mm in front of the endoscope. Good securing of the shunt stylet with the telescope was found to be essential for constant and accurate navigation. Conclusion: Navigation-enabled endoscopes provide the surgeon with the advantage of sustained stereotactic anatomical awareness at all times during the surgery. Keywords: telescope, endoscope, image guidance, navigation, lacrimal surgery, powered endoscopic DCR

  4. Outer navigation of a inspection robot by means of feedback of global guidance

    International Nuclear Information System (INIS)

    Segovia de los R, A.; Bucio V, F.; Garduno G, M.

    2008-01-01

    The objective of this article is the presentation of an inspection system to mobile robot navigating in exteriors by means of the employment of a feedback of instantaneous guidance with respect to a global reference throughout moment of the displacement. The robot evolves obeying the commands coming from the one tele operator which indicates the diverse addresses by means of the operation console that the robot should take using for it information provided by an electronic compass. The mobile robot employee in the experimentations is a Pioneer 3-AT, which counts with a sensor series required to obtain an operation of more autonomy. The electronic compass offers geographical information coded in a format SPI, reason for which a micro controller (μC) economic of general use has been an employee for to transfer the information to the format RS-232, originally used by the Pioneer 3-AT. The orientation information received by the robot by means of their serial port RS-232 secondary it is forwarded to the computer hostess in the one which a program Java is used to generate the commands for the robot navigation control and to deploy one graphic interface user utilized to receive the order of the operator. This research is part of an ambitious project in which it is tried to count on an inspection system and monitoring of sites in which risks of high radiation levels could exist, thus a navigation systems in exteriors could be very useful. The complete system will count besides the own sensors of the robot, with certain numbers of agree sensors to the variables that are desired to monitor. The resulting values of such measurements will be visualized in real time in the graphic interface user, thanks to a bidirectional wireless communication among the station of operation and the mobile robot. (Author)

  5. Description of the attitude control, guidance and navigation space replaceable units for automated space servicing of selected NASA missions

    Science.gov (United States)

    Chobotov, V. A.

    1974-01-01

    Control elements such as sensors, momentum exchange devices, and thrusters are described which can be used to define space replaceable units (SRU), in accordance with attitude control, guidance, and navigation performance requirements selected for NASA space serviceable mission spacecraft. A number of SRU's are developed, and their reliability block diagrams are presented. An SRU assignment is given in order to define a set of feasible space serviceable spacecraft for the missions of interest.

  6. Integrated Targeting and Guidance for Powered Planetary Descent

    Science.gov (United States)

    Azimov, Dilmurat M.; Bishop, Robert H.

    2018-02-01

    This paper presents an on-board guidance and targeting design that enables explicit state and thrust vector control and on-board targeting for planetary descent and landing. These capabilities are developed utilizing a new closed-form solution for the constant thrust arc of the braking phase of the powered descent trajectory. The key elements of proven targeting and guidance architectures, including braking and approach phase quartics, are employed. It is demonstrated that implementation of the proposed solution avoids numerical simulation iterations, thereby facilitating on-board execution of targeting procedures during the descent. It is shown that the shape of the braking phase constant thrust arc is highly dependent on initial mass and propulsion system parameters. The analytic solution process is explicit in terms of targeting and guidance parameters, while remaining generic with respect to planetary body and descent trajectory design. These features increase the feasibility of extending the proposed integrated targeting and guidance design to future cargo and robotic landing missions.

  7. Integrating mechanisms of visual guidance in naturalistic language production.

    Science.gov (United States)

    Coco, Moreno I; Keller, Frank

    2015-05-01

    Situated language production requires the integration of visual attention and linguistic processing. Previous work has not conclusively disentangled the role of perceptual scene information and structural sentence information in guiding visual attention. In this paper, we present an eye-tracking study that demonstrates that three types of guidance, perceptual, conceptual, and structural, interact to control visual attention. In a cued language production experiment, we manipulate perceptual (scene clutter) and conceptual guidance (cue animacy) and measure structural guidance (syntactic complexity of the utterance). Analysis of the time course of language production, before and during speech, reveals that all three forms of guidance affect the complexity of visual responses, quantified in terms of the entropy of attentional landscapes and the turbulence of scan patterns, especially during speech. We find that perceptual and conceptual guidance mediate the distribution of attention in the scene, whereas structural guidance closely relates to scan pattern complexity. Furthermore, the eye-voice span of the cued object and its perceptual competitor are similar; its latency mediated by both perceptual and structural guidance. These results rule out a strict interpretation of structural guidance as the single dominant form of visual guidance in situated language production. Rather, the phase of the task and the associated demands of cross-modal cognitive processing determine the mechanisms that guide attention.

  8. The Role of Guidance, Navigation, and Control in Hypersonic Vehicle Multidisciplinary Design and Optimization

    Science.gov (United States)

    Ouzts, Peter J.; Soloway, Donald I.; Moerder, Daniel D.; Wolpert, David H.; Benavides, Jose Victor

    2009-01-01

    Airbreathing hypersonic systems offer distinct performance advantages over rocket-based systems for space access vehicles. However, these performance advantages are dependent upon advances in current state-of-the-art technologies in many areas such as ram/scramjet propulsion integration, high temperature materials, aero-elastic structures, thermal protection systems, transition to hypersonics and hypersonic control elements within the framework of complex physics and new design methods. The complex interactions between elements of an airbreathing hypersonic vehicle represent a new paradigm in vehicle design to achieve the optimal performance necessary to meet space access mission objectives. In the past, guidance, navigation, and control (GNC) analysis often follows completion of the vehicle conceptual design process. Individual component groups design subsystems which are then integrated into a vehicle configuration. GNC is presented the task of developing control approaches to meet vehicle performance objectives given that configuration. This approach may be sufficient for vehicles where significant performance margins exist. However, for higher performance vehicles engaging the GNC discipline too late in the design cycle has been costly. For example, the X-29 experimental flight vehicle was built as a technology demonstrator. One of the many technologies to be demonstrated was the use of light-weight material composites for structural components. The use of light-weight materials increased the flexibility of the X- 29 beyond that of conventional metal alloy constructed aircraft. This effect was not considered when the vehicle control system was designed and built. The impact of this is that the control system did not have enough control authority to compensate for the effects of the first fundamental structural mode of the vehicle. As a result, the resulting pitch rate response of the vehicle was below specification and no post-design changes could recover the

  9. Interfacing Space Communications and Navigation Network Simulation with Distributed System Integration Laboratories (DSIL)

    Science.gov (United States)

    Jennings, Esther H.; Nguyen, Sam P.; Wang, Shin-Ywan; Woo, Simon S.

    2008-01-01

    NASA's planned Lunar missions will involve multiple NASA centers where each participating center has a specific role and specialization. In this vision, the Constellation program (CxP)'s Distributed System Integration Laboratories (DSIL) architecture consist of multiple System Integration Labs (SILs), with simulators, emulators, testlabs and control centers interacting with each other over a broadband network to perform test and verification for mission scenarios. To support the end-to-end simulation and emulation effort of NASA' exploration initiatives, different NASA centers are interconnected to participate in distributed simulations. Currently, DSIL has interconnections among the following NASA centers: Johnson Space Center (JSC), Kennedy Space Center (KSC), Marshall Space Flight Center (MSFC) and Jet Propulsion Laboratory (JPL). Through interconnections and interactions among different NASA centers, critical resources and data can be shared, while independent simulations can be performed simultaneously at different NASA locations, to effectively utilize the simulation and emulation capabilities at each center. Furthermore, the development of DSIL can maximally leverage the existing project simulation and testing plans. In this work, we describe the specific role and development activities at JPL for Space Communications and Navigation Network (SCaN) simulator using the Multi-mission Advanced Communications Hybrid Environment for Test and Evaluation (MACHETE) tool to simulate communications effects among mission assets. Using MACHETE, different space network configurations among spacecrafts and ground systems of various parameter sets can be simulated. Data that is necessary for tracking, navigation, and guidance of spacecrafts such as Crew Exploration Vehicle (CEV), Crew Launch Vehicle (CLV), and Lunar Relay Satellite (LRS) and orbit calculation data are disseminated to different NASA centers and updated periodically using the High Level Architecture (HLA). In

  10. On-the-fly Locata/inertial navigation system integration for precise maritime application

    Science.gov (United States)

    Jiang, Wei; Li, Yong; Rizos, Chris

    2013-10-01

    The application of Global Navigation Satellite System (GNSS) technology has meant that marine navigators have greater access to a more consistent and accurate positioning capability than ever before. However, GNSS may not be able to meet all emerging navigation performance requirements for maritime applications with respect to service robustness, accuracy, integrity and availability. In particular, applications in port areas (for example automated docking) and in constricted waterways, have very stringent performance requirements. Even when an integrated inertial navigation system (INS)/GNSS device is used there may still be performance gaps. GNSS signals are easily blocked or interfered with, and sometimes the satellite geometry may not be good enough for high accuracy and high reliability applications. Furthermore, the INS accuracy degrades rapidly during GNSS outages. This paper investigates the use of a portable ground-based positioning system, known as ‘Locata’, which was integrated with an INS, to provide accurate navigation in a marine environment without reliance on GNSS signals. An ‘on-the-fly’ Locata resolution algorithm that takes advantage of geometry change via an extended Kalman filter is proposed in this paper. Single-differenced Locata carrier phase measurements are utilized to achieve accurate and reliable solutions. A ‘loosely coupled’ decentralized Locata/INS integration architecture based on the Kalman filter is used for data processing. In order to evaluate the system performance, a field trial was conducted on Sydney Harbour. A Locata network consisting of eight Locata transmitters was set up near the Sydney Harbour Bridge. The experiment demonstrated that the Locata on-the-fly (OTF) algorithm is effective and can improve the system accuracy in comparison with the conventional ‘known point initialization’ (KPI) method. After the OTF and KPI comparison, the OTF Locata/INS integration is then assessed further and its performance

  11. On-the-fly Locata/inertial navigation system integration for precise maritime application

    International Nuclear Information System (INIS)

    Jiang, Wei; Li, Yong; Rizos, Chris

    2013-01-01

    The application of Global Navigation Satellite System (GNSS) technology has meant that marine navigators have greater access to a more consistent and accurate positioning capability than ever before. However, GNSS may not be able to meet all emerging navigation performance requirements for maritime applications with respect to service robustness, accuracy, integrity and availability. In particular, applications in port areas (for example automated docking) and in constricted waterways, have very stringent performance requirements. Even when an integrated inertial navigation system (INS)/GNSS device is used there may still be performance gaps. GNSS signals are easily blocked or interfered with, and sometimes the satellite geometry may not be good enough for high accuracy and high reliability applications. Furthermore, the INS accuracy degrades rapidly during GNSS outages. This paper investigates the use of a portable ground-based positioning system, known as ‘Locata’, which was integrated with an INS, to provide accurate navigation in a marine environment without reliance on GNSS signals. An ‘on-the-fly’ Locata resolution algorithm that takes advantage of geometry change via an extended Kalman filter is proposed in this paper. Single-differenced Locata carrier phase measurements are utilized to achieve accurate and reliable solutions. A ‘loosely coupled’ decentralized Locata/INS integration architecture based on the Kalman filter is used for data processing. In order to evaluate the system performance, a field trial was conducted on Sydney Harbour. A Locata network consisting of eight Locata transmitters was set up near the Sydney Harbour Bridge. The experiment demonstrated that the Locata on-the-fly (OTF) algorithm is effective and can improve the system accuracy in comparison with the conventional ‘known point initialization’ (KPI) method. After the OTF and KPI comparison, the OTF Locata/INS integration is then assessed further and its performance

  12. Mobile C-arm cone-beam CT for guidance of spine surgery: Image quality, radiation dose, and integration with interventional guidance

    Energy Technology Data Exchange (ETDEWEB)

    Schafer, S.; Nithiananthan, S.; Mirota, D. J.; Uneri, A.; Stayman, J. W.; Zbijewski, W.; Schmidgunst, C.; Kleinszig, G.; Khanna, A. J.; Siewerdsen, J. H. [Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland 21202 (United States); Department of Computer Science, Johns Hopkins University, Baltimore, Maryland 21218 (United States); Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland 21202 (United States); Siemens Healthcare XP Division, Erlangen (Germany); Department of Orthopaedic Surgery, Johns Hopkins University, Baltimore, Maryland 21239 (United States); Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland 21202 and Department of Computer Science, Johns Hopkins University, Baltimore, Maryland 21218 (United States)

    2011-08-15

    , and {approx}3-4 lower at the exit side). The in-room dose (microsievert) per unit scan dose (milligray) ranged from {approx}21 {mu}Sv/mGy on average at tableside to {approx}0.1 {mu}Sv/mGy at 2.0 m distance to isocenter. All protocols involve surgical staff stepping behind a shield wall for each CBCT scan, therefore imparting {approx}zero dose to staff. Protocol implementation in preclinical cadaveric studies demonstrate integration of the C-arm with a navigation system for spine surgery guidance-specifically, minimally invasive vertebroplasty in which the system provided accurate guidance and visualization of needle placement and bone cement distribution. Cumulative dose including multiple intraoperative scans was {approx}11.5 mGy for CBCT-guided thoracic vertebroplasty and {approx}23.2 mGy for lumbar vertebroplasty, with dose to staff at tableside reduced to {approx}1 min of fluoroscopy time ({approx}40-60 {mu}Sv), compared to 5-11 min for the conventional approach. Conclusions: Intraoperative CBCT using a high-performance mobile C-arm prototype demonstrates image quality suitable to guidance of spine surgery, with task-specific protocols providing an important basis for minimizing radiation dose, while maintaining image quality sufficient for surgical guidance. Images demonstrate a significant advance in spatial resolution and soft-tissue visibility, and CBCT guidance offers the potential to reduce fluoroscopy reliance, reducing cumulative dose to patient and staff. Integration with a surgical guidance system demonstrates precise tracking and visualization in up-to-date images (alleviating reliance on preoperative images only), including detection of errors or suboptimal surgical outcomes in the operating room.

  13. Observability-Based Guidance and Sensor Placement

    Science.gov (United States)

    Hinson, Brian T.

    Control system performance is highly dependent on the quality of sensor information available. In a growing number of applications, however, the control task must be accomplished with limited sensing capabilities. This thesis addresses these types of problems from a control-theoretic point-of-view, leveraging system nonlinearities to improve sensing performance. Using measures of observability as an information quality metric, guidance trajectories and sensor distributions are designed to improve the quality of sensor information. An observability-based sensor placement algorithm is developed to compute optimal sensor configurations for a general nonlinear system. The algorithm utilizes a simulation of the nonlinear system as the source of input data, and convex optimization provides a scalable solution method. The sensor placement algorithm is applied to a study of gyroscopic sensing in insect wings. The sensor placement algorithm reveals information-rich areas on flexible insect wings, and a comparison to biological data suggests that insect wings are capable of acting as gyroscopic sensors. An observability-based guidance framework is developed for robotic navigation with limited inertial sensing. Guidance trajectories and algorithms are developed for range-only and bearing-only navigation that improve navigation accuracy. Simulations and experiments with an underwater vehicle demonstrate that the observability measure allows tuning of the navigation uncertainty.

  14. Kalman Filter Integration of Modern Guidance and Navigation Systems

    Science.gov (United States)

    1989-07-04

    0 AB~ dI RKUv 0 -l/T2 0 0 ]IAMI.O +OV w L j OD 0 0 0 PLRZODI +( dt LP2 J o 2 2/TlJ~ 2 where _ is a zero mean Gaussian white ( ZaW ) noise process, and...Integration schemes, 12 simulation tuns of 4-day voyages were performed. We decided to compare the most effivient algorithm, using 12 states, to the ’most

  15. An IMM-Aided ZUPT Methodology for an INS/DVL Integrated Navigation System.

    Science.gov (United States)

    Yao, Yiqing; Xu, Xiaosu; Xu, Xiang

    2017-09-05

    Inertial navigation system (INS)/Doppler velocity log (DVL) integration is the most common navigation solution for underwater vehicles. Due to the complex underwater environment, the velocity information provided by DVL always contains some errors. To improve navigation accuracy, zero velocity update (ZUPT) technology is considered, which is an effective algorithm for land vehicles to mitigate the navigation error during the pure INS mode. However, in contrast to ground vehicles, the ZUPT solution cannot be used directly for underwater vehicles because of the existence of the water current. In order to leverage the strengths of the ZUPT method and the INS/DVL solution, an interactive multiple model (IMM)-aided ZUPT methodology for the INS/DVL-integrated underwater navigation system is proposed. Both the INS/DVL and INS/ZUPT models are constructed and operated in parallel, with weights calculated according to their innovations and innovation covariance matrices. Simulations are conducted to evaluate the proposed algorithm. The results indicate that the IMM-aided ZUPT solution outperforms both the INS/DVL solution and the INS/ZUPT solution in the underwater environment, which can properly distinguish between the ZUPT and non-ZUPT conditions. In addition, during DVL outage, the effectiveness of the proposed algorithm is also verified.

  16. Integration of existing systematic reviews into new reviews: identification of guidance needs

    Science.gov (United States)

    2014-01-01

    Background An exponential increase in the number of systematic reviews published, and constrained resources for new reviews, means that there is an urgent need for guidance on explicitly and transparently integrating existing reviews into new systematic reviews. The objectives of this paper are: 1) to identify areas where existing guidance may be adopted or adapted, and 2) to suggest areas for future guidance development. Methods We searched documents and websites from healthcare focused systematic review organizations to identify and, where available, to summarize relevant guidance on the use of existing systematic reviews. We conducted informational interviews with members of Evidence-based Practice Centers (EPCs) to gather experiences in integrating existing systematic reviews, including common issues and challenges, as well as potential solutions. Results There was consensus among systematic review organizations and the EPCs about some aspects of incorporating existing systematic reviews into new reviews. Current guidance may be used in assessing the relevance of prior reviews and in scanning references of prior reviews to identify studies for a new review. However, areas of challenge remain. Areas in need of guidance include how to synthesize, grade the strength of, and present bodies of evidence composed of primary studies and existing systematic reviews. For instance, empiric evidence is needed regarding how to quality check data abstraction and when and how to use study-level risk of bias assessments from prior reviews. Conclusions There remain areas of uncertainty for how to integrate existing systematic reviews into new reviews. Methods research and consensus processes among systematic review organizations are needed to develop guidance to address these challenges. PMID:24956937

  17. The impact of fMRI on multimodal navigation in surgery of cerebral lesions: four years clinical experience

    International Nuclear Information System (INIS)

    Wurm, Gabriele; Schnizer, Mathilde; Fellner, Claudia

    2008-01-01

    Neuronavigation with display of intraoperative structures, instrument locations, orientation and relationships to nearby structures can increase anatomic precision while enhancing the surgeon's confidence and his/her perception of safety. Combination of neuronavigation with functional imaging provides multimodal guidance for surgery of cerebral lesions. We evaluated the impact of functional MRI (fMRI) on surgical decision making and outcome. A neuronavigational device (StealthStation (tm), Medtronic Inc.) was used as platform to merge fMRI data with anatomic images, and to implement intraoperative multimodal guidance. In a 52-month period, where 977 surgical procedures were performed with the aid of neuronavigation, 88 patients underwent image-guided procedures using multimodal guidance. Patient, surgical and outcome data of this series was prospectively collected. Evaluation of 88 procedures on cerebral lesions in complex regions where fMRI data were integrated using the navigation system demonstrated that the additional information was presented in a user-friendly way. Computer assisted fMRI integration was found to be especially helpful in planning the best approach, in assessing alternative approaches, and in defining the extent of the surgical exposure. Furthermore, the surgeons found it more effective to interpret fMRI information when shown in a navigation system as compared to the traditional display on a light board or monitor. Multimodal navigation enhanced by fMRI was judged useful for optimization of surgery of cerebral lesions, especially in and around eloquent regions by experienced neurosurgeons. (orig.)

  18. Statistical methods for launch vehicle guidance, navigation, and control (GN&C) system design and analysis

    Science.gov (United States)

    Rose, Michael Benjamin

    A novel trajectory and attitude control and navigation analysis tool for powered ascent is developed. The tool is capable of rapid trade-space analysis and is designed to ultimately reduce turnaround time for launch vehicle design, mission planning, and redesign work. It is streamlined to quickly determine trajectory and attitude control dispersions, propellant dispersions, orbit insertion dispersions, and navigation errors and their sensitivities to sensor errors, actuator execution uncertainties, and random disturbances. The tool is developed by applying both Monte Carlo and linear covariance analysis techniques to a closed-loop, launch vehicle guidance, navigation, and control (GN&C) system. The nonlinear dynamics and flight GN&C software models of a closed-loop, six-degree-of-freedom (6-DOF), Monte Carlo simulation are formulated and developed. The nominal reference trajectory (NRT) for the proposed lunar ascent trajectory is defined and generated. The Monte Carlo truth models and GN&C algorithms are linearized about the NRT, the linear covariance equations are formulated, and the linear covariance simulation is developed. The performance of the launch vehicle GN&C system is evaluated using both Monte Carlo and linear covariance techniques and their trajectory and attitude control dispersion, propellant dispersion, orbit insertion dispersion, and navigation error results are validated and compared. Statistical results from linear covariance analysis are generally within 10% of Monte Carlo results, and in most cases the differences are less than 5%. This is an excellent result given the many complex nonlinearities that are embedded in the ascent GN&C problem. Moreover, the real value of this tool lies in its speed, where the linear covariance simulation is 1036.62 times faster than the Monte Carlo simulation. Although the application and results presented are for a lunar, single-stage-to-orbit (SSTO), ascent vehicle, the tools, techniques, and mathematical

  19. Indoor Navigation Design Integrated with Smart Phones and Rfid Devices

    Science.gov (United States)

    Ortakci, Y.; Demiral, E.; Atila, U.; Karas, I. R.

    2015-10-01

    High rise, complex and huge buildings in the cities are almost like a small city with their tens of floors, hundreds of corridors and rooms and passages. Due to size and complexity of these buildings, people need guidance to find their way to the destination in these buildings. In this study, a mobile application is developed to visualize pedestrian's indoor position as 3D in their smartphone and RFID Technology is used to detect the position of pedestrian. While the pedestrian is walking on his/her way on the route, smartphone will guide the pedestrian by displaying the photos of indoor environment on the route. Along the tour, an RFID (Radio-Frequency Identification) device is integrated to the system. The pedestrian will carry the RFID device during his/her tour in the building. The RFID device will send the position data to the server directly in every two seconds periodically. On the other side, the pedestrian will just select the destination point in the mobile application on smartphone and sent the destination point to the server. The shortest path from the pedestrian position to the destination point is found out by the script on the server. This script also sends the environment photo of the first node on the acquired shortest path to the client as an indoor navigation module.

  20. Visual map and instruction-based bicycle navigation: a comparison of effects on behaviour.

    Science.gov (United States)

    de Waard, Dick; Westerhuis, Frank; Joling, Danielle; Weiland, Stella; Stadtbäumer, Ronja; Kaltofen, Leonie

    2017-09-01

    Cycling with a classic paper map was compared with navigating with a moving map displayed on a smartphone, and with auditory, and visual turn-by-turn route guidance. Spatial skills were found to be related to navigation performance, however only when navigating from a paper or electronic map, not with turn-by-turn (instruction based) navigation. While navigating, 25% of the time cyclists fixated at the devices that present visual information. Navigating from a paper map required most mental effort and both young and older cyclists preferred electronic over paper map navigation. In particular a turn-by-turn dedicated guidance device was favoured. Visual maps are in particular useful for cyclists with higher spatial skills. Turn-by-turn information is used by all cyclists, and it is useful to make these directions available in all devices. Practitioner Summary: Electronic navigation devices are preferred over a paper map. People with lower spatial skills benefit most from turn-by-turn guidance information, presented either auditory or on a dedicated device. People with higher spatial skills perform well with all devices. It is advised to keep in mind that all users benefit from turn-by-turn information when developing a navigation device for cyclists.

  1. Automated low-thrust guidance for the orbital maneuvering vehicle

    Science.gov (United States)

    Rose, Richard E.; Schmeichel, Harry; Shortwell, Charles P.; Werner, Ronald A.

    1988-01-01

    This paper describes the highly autonomous OMV Guidance Navigation and Control system. Emphasis is placed on a key feature of the design, the low thrust guidance algorithm. The two guidance modes, orbit change guidance and rendezvous guidance, are discussed in detail. It is shown how OMV will automatically transfer from its initial orbit to an arbitrary target orbit and reach a specified rendezvous position relative to the target vehicle.

  2. On a New Family of Kalman Filter Algorithms for Integrated Navigation

    Science.gov (United States)

    Mahboub, V.; Saadatseresht, M.; Ardalan, A. A.

    2017-09-01

    Here we present a review on a new family of Kalman filter algorithms which recently developed for integrated navigation. In particular it is useful for vision based navigation due to the type of data. Here we mainly focus on three algorithms namely weighted Total Kalman filter (WTKF), integrated Kalman filter (IKF) and constrained integrated Kalman filter (CIKF). The common characteristic of these algorithms is that they can consider the neglected random observed quantities which may appear in the dynamic model. Moreover, our approach makes use of condition equations and straightforward variance propagation rules. The WTKF algorithm can deal with problems with arbitrary weight matrixes. Both of the observation equations and system equations can be dynamic-errors-in-variables (DEIV) models in the IKF algorithms. In some problems a quadratic constraint may exist. They can be solved by CIKF algorithm. Finally, we compare four algorithms WTKF, IKF, CIKF and EKF in numerical examples.

  3. Integrated guidance and control design of a flight vehicle with side-window detection

    Directory of Open Access Journals (Sweden)

    Tianyu ZHENG

    2018-04-01

    Full Text Available This paper considers the guidance and control problem of a flight vehicle with side-window detection. In order to guarantee the target remaining in the seeker's sight of view, the line of sight and the attitude of the flight vehicle should be under some constraints caused by the side-window, which leads to coupling between the guidance and the attitude dynamics model. To deal with the side-window constraints and the coupling, a novel Integrated Guidance and Control (IGC design approach is proposed. Firstly, the relative motion equations are derived in the body-Line of Sight (LOS coordinate system. And the guidance and control problem of the flight vehicle is formulated into an IGC problem with state constraints. Then, based on the singular perturbation method, the IGC problem is decomposed into the control design of the quasi-steady-state subsystem and the boundary-layer subsystem which can be designed separately. Finally, the receding horizon control is applied to the control design for the two subsystems. Simulation results show the effectiveness of the proposed approach. Keywords: Integrated guidance and control, Receding horizon control, Side-window detection, Singular perturbation, Terminal guidance

  4. A Response to Papatola and Lustig's Paper on Navigating a Managed Care Peer Review: Guidance for Clinicians Using Applied Behavior Analysis in the Treatment of Children on the Autism Spectrum.

    Science.gov (United States)

    Kornack, Julie; Herscovitch, Brandon; Williams, Ashley L

    2017-12-01

    In their 2016 article, "Navigating a Managed Care Peer Review: Guidance for Clinicians Using Applied Behavior Analysis [ABA] in the Treatment of Children on the Autism Spectrum," Papatola and Lustig provide an overview of the managed care process, discuss the medical necessity of ABA, and offer guidance to clinicians on how to navigate the managed care peer review process. Given that the authors are employed by a large international health insurance carrier and conduct peer reviews on behalf of that organization, this response seeks to provide guidance from both the clinical and public policy perspectives that reflect best practices in the field of autism treatment. This response is not written with the intention of providing or replacing legal advice; rather, this paper offers health care providers of ABA an essential understanding of some of the laws that govern and support their efforts to secure medically necessary treatment and the mechanisms in place with which to challenge decisions by managed care organizations, health plans, and health insurance issuers that may be contrary to best practices. Finally, suggestions are offered on how to navigate a peer review to ensure optimal outcomes and, when necessary, to lay the groundwork to overturn a funding source decision that does not reflect best practices or the standard of care in ABA-based autism treatment.

  5. Optimizing MR imaging-guided navigation for focused ultrasound interventions in the brain

    Science.gov (United States)

    Werner, B.; Martin, E.; Bauer, R.; O'Gorman, R.

    2017-03-01

    MR imaging during transcranial MR imaging-guided Focused Ultrasound surgery (tcMRIgFUS) is challenging due to the complex ultrasound transducer setup and the water bolus used for acoustic coupling. Achievable image quality in the tcMRIgFUS setup using the standard body coil is significantly inferior to current neuroradiologic standards. As a consequence, MR image guidance for precise navigation in functional neurosurgical interventions using tcMRIgFUS is basically limited to the acquisition of MR coordinates of salient landmarks such as the anterior and posterior commissure for aligning a stereotactic atlas. Here, we show how improved MR image quality provided by a custom built MR coil and optimized MR imaging sequences can support imaging-guided navigation for functional tcMRIgFUS neurosurgery by visualizing anatomical landmarks that can be integrated into the navigation process to accommodate for patient specific anatomy.

  6. Software engineering of a navigation and guidance system for commercial aircraft

    Science.gov (United States)

    Lachmann, S. G.; Mckinstry, R. G.

    1975-01-01

    The avionics experimental configuration of the considered system is briefly reviewed, taking into account the concept of an advanced air traffic management system, flight critical and noncritical functions, and display system characteristics. Cockpit displays and the navigation computer are examined. Attention is given to the functions performed in the navigation computer, major programs in the navigation computer, and questions of software development.

  7. Spacecraft guidance, navigation, and control requirements for an intelligent plug-n-play avionics (PAPA) architecture

    Science.gov (United States)

    Kulkarni, Nilesh; Krishnakumar, Kalmaje

    2005-01-01

    The objective of this research is to design an intelligent plug-n-play avionics system that provides a reconfigurable platform for supporting the guidance, navigation and control (GN&C) requirements for different elements of the space exploration mission. The focus of this study is to look at the specific requirements for a spacecraft that needs to go from earth to moon and back. In this regard we will identify the different GN&C problems in various phases of flight that need to be addressed for designing such a plug-n-play avionics system. The Apollo and the Space Shuttle programs provide rich literature in terms of understanding some of the general GN&C requirements for a space vehicle. The relevant literature is reviewed which helps in narrowing down the different GN&C algorithms that need to be supported along with their individual requirements.

  8. Independent Orbiter Assessment (IOA): Assessment of the guidance, navigation, and control subsystem FMEA/CIL

    Science.gov (United States)

    Trahan, W. H.; Odonnell, R. A.; Pietz, K. C.; Drapela, L. J.

    1988-01-01

    The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the Guidance, Navigation, and Control System (GNC) hardware, generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to the NASA FMEA/CIL baseline with proposed Post 51-L updates included. A resolution of each discrepancy from the comparison is provided through additional analysis as required. The results of that comparison for the Orbiter GNC hardware is documented. The IOA product for the GNC analysis consisted of 141 failure mode worksheets that resulted in 24 potential critical items being identified. Comparison was made to the NASA baseline which consisted of 148 FMEAs and 36 CIL items. This comparison produced agreement on all but 56 FMEAs which caused differences in zero CIL items.

  9. Integrated navigation and control software system for MRI-guided robotic prostate interventions.

    Science.gov (United States)

    Tokuda, Junichi; Fischer, Gregory S; DiMaio, Simon P; Gobbi, David G; Csoma, Csaba; Mewes, Philip W; Fichtinger, Gabor; Tempany, Clare M; Hata, Nobuhiko

    2010-01-01

    A software system to provide intuitive navigation for MRI-guided robotic transperineal prostate therapy is presented. In the system, the robot control unit, the MRI scanner, and the open-source navigation software are connected together via Ethernet to exchange commands, coordinates, and images using an open network communication protocol, OpenIGTLink. The system has six states called "workphases" that provide the necessary synchronization of all components during each stage of the clinical workflow, and the user interface guides the operator linearly through these workphases. On top of this framework, the software provides the following features for needle guidance: interactive target planning; 3D image visualization with current needle position; treatment monitoring through real-time MR images of needle trajectories in the prostate. These features are supported by calibration of robot and image coordinates by fiducial-based registration. Performance tests show that the registration error of the system was 2.6mm within the prostate volume. Registered real-time 2D images were displayed 1.97 s after the image location is specified. Copyright 2009 Elsevier Ltd. All rights reserved.

  10. Integrated navigation and control software system for MRI-guided robotic prostate interventions

    Science.gov (United States)

    Tokuda, Junichi; Fischer, Gregory S.; DiMaio, Simon P.; Gobbi, David G.; Csoma, Csaba; Mewes, Philip W.; Fichtinger, Gabor; Tempany, Clare M.; Hata, Nobuhiko

    2010-01-01

    A software system to provide intuitive navigation for MRI-guided robotic transperineal prostate therapy is presented. In the system, the robot control unit, the MRI scanner, and the open-source navigation software are connected together via Ethernet to exchange commands, coordinates, and images using an open network communication protocol, OpenIGTLink. The system has six states called “workphases” that provide the necessary synchronization of all components during each stage of the clinical workflow, and the user interface guides the operator linearly through these workphases. On top of this framework, the software provides the following features for needle guidance: interactive target planning; 3D image visualization with current needle position; treatment monitoring through real-time MR images of needle trajectories in the prostate. These features are supported by calibration of robot and image coordinates by fiducial-based registration. Performance tests show that the registration error of the system was 2.6 mm within the prostate volume. Registered real-time 2D images were displayed 1.97 s after the image location is specified. PMID:19699057

  11. An Improved Strong Tracking Cubature Kalman Filter for GPS/INS Integrated Navigation Systems.

    Science.gov (United States)

    Feng, Kaiqiang; Li, Jie; Zhang, Xi; Zhang, Xiaoming; Shen, Chong; Cao, Huiliang; Yang, Yanyu; Liu, Jun

    2018-06-12

    The cubature Kalman filter (CKF) is widely used in the application of GPS/INS integrated navigation systems. However, its performance may decline in accuracy and even diverge in the presence of process uncertainties. To solve the problem, a new algorithm named improved strong tracking seventh-degree spherical simplex-radial cubature Kalman filter (IST-7thSSRCKF) is proposed in this paper. In the proposed algorithm, the effect of process uncertainty is mitigated by using the improved strong tracking Kalman filter technique, in which the hypothesis testing method is adopted to identify the process uncertainty and the prior state estimate covariance in the CKF is further modified online according to the change in vehicle dynamics. In addition, a new seventh-degree spherical simplex-radial rule is employed to further improve the estimation accuracy of the strong tracking cubature Kalman filter. In this way, the proposed comprehensive algorithm integrates the advantage of 7thSSRCKF’s high accuracy and strong tracking filter’s strong robustness against process uncertainties. The GPS/INS integrated navigation problem with significant dynamic model errors is utilized to validate the performance of proposed IST-7thSSRCKF. Results demonstrate that the improved strong tracking cubature Kalman filter can achieve higher accuracy than the existing CKF and ST-CKF, and is more robust for the GPS/INS integrated navigation system.

  12. Adaptive Iterated Extended Kalman Filter and Its Application to Autonomous Integrated Navigation for Indoor Robot

    Directory of Open Access Journals (Sweden)

    Yuan Xu

    2014-01-01

    Full Text Available As the core of the integrated navigation system, the data fusion algorithm should be designed seriously. In order to improve the accuracy of data fusion, this work proposed an adaptive iterated extended Kalman (AIEKF which used the noise statistics estimator in the iterated extended Kalman (IEKF, and then AIEKF is used to deal with the nonlinear problem in the inertial navigation systems (INS/wireless sensors networks (WSNs-integrated navigation system. Practical test has been done to evaluate the performance of the proposed method. The results show that the proposed method is effective to reduce the mean root-mean-square error (RMSE of position by about 92.53%, 67.93%, 55.97%, and 30.09% compared with the INS only, WSN, EKF, and IEKF.

  13. Integrated navigation fusion strategy of INS/UWB for indoor carrier attitude angle and position synchronous tracking.

    Science.gov (United States)

    Fan, Qigao; Wu, Yaheng; Hui, Jing; Wu, Lei; Yu, Zhenzhong; Zhou, Lijuan

    2014-01-01

    In some GPS failure conditions, positioning for mobile target is difficult. This paper proposed a new method based on INS/UWB for attitude angle and position synchronous tracking of indoor carrier. Firstly, error model of INS/UWB integrated system is built, including error equation of INS and UWB. And combined filtering model of INS/UWB is researched. Simulation results show that the two subsystems are complementary. Secondly, integrated navigation data fusion strategy of INS/UWB based on Kalman filtering theory is proposed. Simulation results show that FAKF method is better than the conventional Kalman filtering. Finally, an indoor experiment platform is established to verify the integrated navigation theory of INS/UWB, which is geared to the needs of coal mine working environment. Static and dynamic positioning results show that the INS/UWB integrated navigation system is stable and real-time, positioning precision meets the requirements of working condition and is better than any independent subsystem.

  14. Marine and Hydrokinetic Renewable Energy Technologies: Potential Navigational Impacts and Mitigation Measures

    Energy Technology Data Exchange (ETDEWEB)

    Cool, Richard, M.; Hudon, Thomas, J.; Basco, David, R.; Rondorf, Neil, E.

    2009-12-10

    On April 15, 2008, the Department of Energy (DOE) issued a Funding Opportunity Announcement for Advanced Water Power Projects which included a Topic Area for Marine and Hydrokinetic Renewable Energy Market Acceleration Projects. Within this Topic Area, DOE identified potential navigational impacts of marine and hydrokinetic renewable energy technologies and measures to prevent adverse impacts on navigation as a sub-topic area. DOE defines marine and hydrokinetic technologies as those capable of utilizing one or more of the following resource categories for energy generation: ocean waves; tides or ocean currents; free flowing water in rivers or streams; and energy generation from the differentials in ocean temperature. PCCI was awarded Cooperative Agreement DE-FC36-08GO18177 from the DOE to identify the potential navigational impacts and mitigation measures for marine hydrokinetic technologies, as summarized herein. The contract also required cooperation with the U.S. Coast Guard (USCG) and two recipients of awards (Pacific Energy Ventures and reVision) in a sub-topic area to develop a protocol to identify streamlined, best-siting practices. Over the period of this contract, PCCI and our sub-consultants, David Basco, Ph.D., and Neil Rondorf of Science Applications International Corporation, met with USCG headquarters personnel, with U.S. Army Corps of Engineers headquarters and regional personnel, with U.S. Navy regional personnel and other ocean users in order to develop an understanding of existing practices for the identification of navigational impacts that might occur during construction, operation, maintenance, and decommissioning. At these same meetings, “standard” and potential mitigation measures were discussed so that guidance could be prepared for project developers. Concurrently, PCCI reviewed navigation guidance published by the USCG and international community. This report summarizes the results of this effort, provides guidance in the form of a

  15. Integration of a 3D perspective view in the navigation display: featuring pilot's mental model

    Science.gov (United States)

    Ebrecht, L.; Schmerwitz, S.

    2015-05-01

    Synthetic vision systems (SVS) appear as spreading technology in the avionic domain. Several studies prove enhanced situational awareness when using synthetic vision. Since the introduction of synthetic vision a steady change and evolution started concerning the primary flight display (PFD) and the navigation display (ND). The main improvements of the ND comprise the representation of colored ground proximity warning systems (EGPWS), weather radar, and TCAS information. Synthetic vision seems to offer high potential to further enhance cockpit display systems. Especially, concerning the current trend having a 3D perspective view in a SVS-PFD while leaving the navigational content as well as methods of interaction unchanged the question arouses if and how the gap between both displays might evolve to a serious problem. This issue becomes important in relation to the transition and combination of strategic and tactical flight guidance. Hence, pros and cons of 2D and 3D views generally as well as the gap between the egocentric perspective 3D view of the PFD and the exocentric 2D top and side view of the ND will be discussed. Further a concept for the integration of a 3D perspective view, i.e., bird's eye view, in synthetic vision ND will be presented. The combination of 2D and 3D views in the ND enables a better correlation of the ND and the PFD. Additionally, this supports the building of pilot's mental model. The authors believe it will improve the situational and spatial awareness. It might prove to further raise the safety margin when operating in mountainous areas.

  16. Integrated detection, estimation, and guidance in pursuit of a maneuvering target

    Science.gov (United States)

    Dionne, Dany

    The thesis focuses on efficient solutions of non-cooperative pursuit-evasion games with imperfect information on the state of the system. This problem is important in the context of interception of future maneuverable ballistic missiles. However, the theoretical developments are expected to find application to a broad class of hybrid control and estimation problems in industry. The validity of the results is nevertheless confirmed using a benchmark problem in the area of terminal guidance. A specific interception scenario between an incoming target with no information and a single interceptor missile with noisy measurements is analyzed in the form of a linear hybrid system subject to additive abrupt changes. The general research is aimed to achieve improved homing accuracy by integrating ideas from detection theory, state estimation theory and guidance. The results achieved can be summarized as follows. (i) Two novel maneuver detectors are developed to diagnose abrupt changes in a class of hybrid systems (detection and isolation of evasive maneuvers): a new implementation of the GLR detector and the novel adaptive- H0 GLR detector. (ii) Two novel state estimators for target tracking are derived using the novel maneuver detectors. The state estimators employ parameterized family of functions to described possible evasive maneuvers. (iii) A novel adaptive Bayesian multiple model predictor of the ballistic miss is developed which employs semi-Markov models and ideas from detection theory. (iv) A novel integrated estimation and guidance scheme that significantly improves the homing accuracy is also presented. The integrated scheme employs banks of estimators and guidance laws, a maneuver detector, and an on-line governor; the scheme is adaptive with respect to the uncertainty affecting the probability density function of the filtered state. (v) A novel discretization technique for the family of continuous-time, game theoretic, bang-bang guidance laws is introduced. The

  17. Integrated flight path planning system and flight control system for unmanned helicopters.

    Science.gov (United States)

    Jan, Shau Shiun; Lin, Yu Hsiang

    2011-01-01

    This paper focuses on the design of an integrated navigation and guidance system for unmanned helicopters. The integrated navigation system comprises two systems: the Flight Path Planning System (FPPS) and the Flight Control System (FCS). The FPPS finds the shortest flight path by the A-Star (A*) algorithm in an adaptive manner for different flight conditions, and the FPPS can add a forbidden zone to stop the unmanned helicopter from crossing over into dangerous areas. In this paper, the FPPS computation time is reduced by the multi-resolution scheme, and the flight path quality is improved by the path smoothing methods. Meanwhile, the FCS includes the fuzzy inference systems (FISs) based on the fuzzy logic. By using expert knowledge and experience to train the FIS, the controller can operate the unmanned helicopter without dynamic models. The integrated system of the FPPS and the FCS is aimed at providing navigation and guidance to the mission destination and it is implemented by coupling the flight simulation software, X-Plane, and the computing software, MATLAB. Simulations are performed and shown in real time three-dimensional animations. Finally, the integrated system is demonstrated to work successfully in controlling the unmanned helicopter to operate in various terrains of a digital elevation model (DEM).

  18. Integrated Flight Path Planning System and Flight Control System for Unmanned Helicopters

    Science.gov (United States)

    Jan, Shau Shiun; Lin, Yu Hsiang

    2011-01-01

    This paper focuses on the design of an integrated navigation and guidance system for unmanned helicopters. The integrated navigation system comprises two systems: the Flight Path Planning System (FPPS) and the Flight Control System (FCS). The FPPS finds the shortest flight path by the A-Star (A*) algorithm in an adaptive manner for different flight conditions, and the FPPS can add a forbidden zone to stop the unmanned helicopter from crossing over into dangerous areas. In this paper, the FPPS computation time is reduced by the multi-resolution scheme, and the flight path quality is improved by the path smoothing methods. Meanwhile, the FCS includes the fuzzy inference systems (FISs) based on the fuzzy logic. By using expert knowledge and experience to train the FIS, the controller can operate the unmanned helicopter without dynamic models. The integrated system of the FPPS and the FCS is aimed at providing navigation and guidance to the mission destination and it is implemented by coupling the flight simulation software, X-Plane, and the computing software, MATLAB. Simulations are performed and shown in real time three-dimensional animations. Finally, the integrated system is demonstrated to work successfully in controlling the unmanned helicopter to operate in various terrains of a digital elevation model (DEM). PMID:22164029

  19. SINS/CNS Nonlinear Integrated Navigation Algorithm for Hypersonic Vehicle

    Directory of Open Access Journals (Sweden)

    Yong-jun Yu

    2015-01-01

    Full Text Available Celestial Navigation System (CNS has characteristics of accurate orientation and strong autonomy and has been widely used in Hypersonic Vehicle. Since the CNS location and orientation mainly depend upon the inertial reference that contains errors caused by gyro drifts and other error factors, traditional Strap-down Inertial Navigation System (SINS/CNS positioning algorithm setting the position error between SINS and CNS as measurement is not effective. The model of altitude azimuth, platform error angles, and horizontal position is designed, and the SINS/CNS tightly integrated algorithm is designed, in which CNS altitude azimuth is set as measurement information. GPF (Gaussian particle filter is introduced to solve the problem of nonlinear filtering. The results of simulation show that the precision of SINS/CNS algorithm which reaches 130 m using three stars is improved effectively.

  20. Working with Research Integrity-Guidance for Research Performing Organisations: The Bonn PRINTEGER Statement.

    Science.gov (United States)

    Forsberg, Ellen-Marie; Anthun, Frank O; Bailey, Sharon; Birchley, Giles; Bout, Henriette; Casonato, Carlo; Fuster, Gloria González; Heinrichs, Bert; Horbach, Serge; Jacobsen, Ingrid Skjæggestad; Janssen, Jacques; Kaiser, Matthias; Lerouge, Inge; van der Meulen, Barend; de Rijcke, Sarah; Saretzki, Thomas; Sutrop, Margit; Tazewell, Marta; Varantola, Krista; Vie, Knut Jørgen; Zwart, Hub; Zöller, Mira

    2018-05-31

    This document presents the Bonn PRINTEGER Consensus Statement: Working with Research Integrity-Guidance for research performing organisations. The aim of the statement is to complement existing instruments by focusing specifically on institutional responsibilities for strengthening integrity. It takes into account the daily challenges and organisational contexts of most researchers. The statement intends to make research integrity challenges recognisable from the work-floor perspective, providing concrete advice on organisational measures to strengthen integrity. The statement, which was concluded February 7th 2018, provides guidance on the following key issues: § 1. Providing information about research integrity § 2. Providing education, training and mentoring § 3. Strengthening a research integrity culture § 4. Facilitating open dialogue § 5. Wise incentive management § 6. Implementing quality assurance procedures § 7. Improving the work environment and work satisfaction § 8. Increasing transparency of misconduct cases § 9. Opening up research § 10. Implementing safe and effective whistle-blowing channels § 11. Protecting the alleged perpetrators § 12. Establishing a research integrity committee and appointing an ombudsperson § 13. Making explicit the applicable standards for research integrity.

  1. Design of guidance laws for lunar pinpoint soft landing

    NARCIS (Netherlands)

    Guo, J.; Han, C.

    2009-01-01

    Future lunar missions ask for the capability to perform precise Guidance, Navigation and Control (GNC) to the selected landing sites on the lunar surface. This paper studies the guidance issues for the lunar pinpoint soft landing problem. The primary contribution of this paper is the design of

  2. An Integrated Approach to Electronic Navigation

    National Research Council Canada - National Science Library

    Shaw, Peter; Pettus, Bill

    2001-01-01

    While the Global Positioning System (GPS) is and will continue to be an excellent navigation system, it is neither flawless nor is it the only system employed in the navigation of today's seagoing warfighters...

  3. Twelve recommendations for integrating existing systematic reviews into new reviews: EPC guidance.

    Science.gov (United States)

    Robinson, Karen A; Chou, Roger; Berkman, Nancy D; Newberry, Sydne J; Fu, Rongwei; Hartling, Lisa; Dryden, Donna; Butler, Mary; Foisy, Michelle; Anderson, Johanna; Motu'apuaka, Makalapua; Relevo, Rose; Guise, Jeanne-Marie; Chang, Stephanie

    2016-02-01

    As time and cost constraints in the conduct of systematic reviews increase, the need to consider the use of existing systematic reviews also increases. We developed guidance on the integration of systematic reviews into new reviews. A workgroup of methodologists from Evidence-based Practice Centers developed consensus-based recommendations. Discussions were informed by a literature scan and by interviews with organizations that conduct systematic reviews. Twelve recommendations were developed addressing selecting reviews, assessing risk of bias, qualitative and quantitative synthesis, and summarizing and assessing body of evidence. We provide preliminary guidance for an efficient and unbiased approach to integrating existing systematic reviews with primary studies in a new review. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. Vision based guidance and flight control in problems of aerial tracking

    Science.gov (United States)

    Stepanyan, Vahram

    The use of visual sensors in providing the necessary information for the autonomous guidance and navigation of the unmanned-air vehicles (UAV) or micro-air vehicles (MAV) applications is inspired by biological systems and is motivated first of all by the reduction of the navigational sensor cost. Also, visual sensors can be more advantageous in military operations since they are difficult to detect. However, the design of a reliable guidance, navigation and control system for aerial vehicles based only on visual information has many unsolved problems, ranging from hardware/software development to pure control-theoretical issues, which are even more complicated when applied to the tracking of maneuvering unknown targets. This dissertation describes guidance law design and implementation algorithms for autonomous tracking of a flying target, when the information about the target's current position is obtained via a monocular camera mounted on the tracking UAV (follower). The visual information is related to the target's relative position in the follower's body frame via the target's apparent size, which is assumed to be constant, but otherwise unknown to the follower. The formulation of the relative dynamics in the inertial frame requires the knowledge of the follower's orientation angles, which are assumed to be known. No information is assumed to be available about the target's dynamics. The follower's objective is to maintain a desired relative position irrespective of the target's motion. Two types of guidance laws are designed and implemented in the dissertation. The first one is a smooth guidance law that guarantees asymptotic tracking of a target, the velocity of which is viewed as a time-varying disturbance, the change in magnitude of which has a bounded integral. The second one is a smooth approximation of a discontinuous guidance law that guarantees bounded tracking with adjustable bounds when the target's acceleration is viewed as a bounded but otherwise

  5. A hybrid data fusion method for GNSS/INS integration navigation system

    Science.gov (United States)

    Yang, Ling; Li, Bofeng; Shen, Yunzhong; Li, Haojun

    2017-04-01

    Although DGNSS is widely used and PPP-GNSS is nowadays a viable precise positioning technology option, the major disadvantage of GNSS still remains: signal blockage due to obstructions in urban and built up environments, and extreme power attenuation of the signals when operated indoors. The combination of GNSS with other sensors, such as a self-contained inertial navigation system (INS), provides an ideal position and attitude determination solution which can not only mitigate the weakness of GNSS, but also bound the INS error that otherwise would grow with time when the INS operates alone. However, the navigation accuracy provided by GNSS/INS strongly depends on the quality and geometry of the GNSS observations, the quality of the INS technology used, and the integration model applied. There are two main types of coupled schemes for integration systems: loosely coupled integration and tightly coupled integration. In loosely coupled integration, position measurements are taken from both systems and combined optimally, usually in a Kalman filter. Tightly coupled integration directly combines the raw pseudorange or carrier phase measurements of GNSS with inertial measurements in an extended Kalman filter. The latter technique improves the ability to resolve ambiguities, i.e. allows a quicker recovery from outage events such as a loss of signal under vegetation. In recent years, tightly coupled differential carrier phase GNSS/INS integration has become popular, because it has the advantage of providing accurate position information even when GPS measurements are rank-deficient in stand-alone processing and is theoretically optimal in a filtering sense, especially in urban navigation applications. However, the heavier computational burden and sensor communication usually complicate the tightly coupled integration and reduce the system efficiency, compared with the loosely coupled integration. In this paper, it has been proved that the loosely coupled and tightly

  6. Navigation in diagnosis and therapy

    International Nuclear Information System (INIS)

    Vannier, Michael W.; Haller, John W.

    1999-01-01

    Image-guided navigation for surgery and other therapeutic interventions has grown in importance in recent years. During image-guided navigation a target is detected, localized and characterized for diagnosis and therapy. Thus, images are used to select, plan, guide and evaluate therapy, thereby reducing invasiveness and improving outcomes. A shift from traditional open surgery to less-invasive image-guided surgery will continue to impact the surgical marketplace. Increases in the speed and capacity of computers and computer networks have enabled image-guided interventions. Key elements in image navigation systems are pre-operative 3D imaging (or real-time image acquisition), a graphical display and interactive input devices, such as surgical instruments with light emitting diodes (LEDs). CT and MRI, 3D imaging devices, are commonplace today and 3D images are useful in complex interventions such as radiation oncology and surgery. For example, integrated surgical imaging workstations can be used for frameless stereotaxy during neurosurgical interventions. In addition, imaging systems are being expanded to include decision aids in diagnosis and treatment. Electronic atlases, such as Voxel Man or others derived from the Visible Human Project, combine a set of image data with non-image knowledge such as anatomic labels. Robot assistants and magnetic guidance technology are being developed for minimally invasive surgery and other therapeutic interventions. Major progress is expected at the interface between the disciplines of radiology and surgery where imaging, intervention and informatics converge

  7. Multimodal system for the planning and guidance of bronchoscopy

    Science.gov (United States)

    Higgins, William E.; Cheirsilp, Ronnarit; Zang, Xiaonan; Byrnes, Patrick

    2015-03-01

    Many technical innovations in multimodal radiologic imaging and bronchoscopy have emerged recently in the effort against lung cancer. Modern X-ray computed-tomography (CT) scanners provide three-dimensional (3D) high-resolution chest images, positron emission tomography (PET) scanners give complementary molecular imaging data, and new integrated PET/CT scanners combine the strengths of both modalities. State-of-the-art bronchoscopes permit minimally invasive tissue sampling, with vivid endobronchial video enabling navigation deep into the airway-tree periphery, while complementary endobronchial ultrasound (EBUS) reveals local views of anatomical structures outside the airways. In addition, image-guided intervention (IGI) systems have proven their utility for CT-based planning and guidance of bronchoscopy. Unfortunately, no IGI system exists that integrates all sources effectively through the complete lung-cancer staging work flow. This paper presents a prototype of a computer-based multimodal IGI system that strives to fill this need. The system combines a wide range of automatic and semi-automatic image-processing tools for multimodal data fusion and procedure planning. It also provides a flexible graphical user interface for follow-on guidance of bronchoscopy/EBUS. Human-study results demonstrate the system's potential.

  8. PREFERENCE FOR MAP SCALE OF IN-CAR ROUTE GUIDANCE AND NAVIGATION SYSTEM

    Directory of Open Access Journals (Sweden)

    Ana Paula Marques Ramos

    Full Text Available Usability issues of maps presented in-car Route Guidance and Navigation System (RGNS may result in serious impacts on traffic safety. To obtain effective RGNS, evaluation of 'user satisfaction' with the system has played a prominent role, since designers can quantify drivers' acceptance about presented information. An important variable related to design of RGNS interfaces refers to select appropriate scale for maps, since it interferes on legibility of maps. Map with good legibility may support drivers comprehend information easily and take decisions during driving task quickly. This paper evaluates drivers' preference for scales used in maps of RGNS. A total of 52 subjects participated of an experiment performed in a parked car. Maps were designed at four different scales 1:1,000, 1:3,000, 1:6,000 and 1:10,000 for a route composed of 13 junctions. Map design was based on cartographic communication principles, such as perceptive grouping and figure-ground segregation. Based on studies cases, we conclude intermediate scales (1:6,000 and 1:3,000 were more acceptable among drivers compared to large scales (1:1,000 and small (1:10,000. RGNS should select scales for maps which supports drivers to quickly identify direction of the maneuver and, simultaneously, get information about surroundings of route. More results are presented and implications discussed

  9. Navigation simulator for the Space Tug vehicle

    Science.gov (United States)

    Colburn, B. K.; Boland, J. S., III; Peters, E. G.

    1977-01-01

    A general simulation program (GSP) for state estimation of a nonlinear space vehicle flight navigation system is developed and used as a basis for evaluating the performance of a Space Tug navigation system. An explanation of the iterative guidance mode (IGM) guidance law, derivation of the dynamics, coordinate frames and state estimation routines are given in order to clarify the assumptions and approximations made. A number of simulation and analytical studies are used to demonstrate the operation of the Tug system. Included in the simulation studies are (1) initial offset vector parameter study; (2) propagation time vs accuracy; (3) measurement noise parametric study and (4) reduction in computational burden of an on-board implementable scheme. From the results of these studies, conclusions and recommendations concerning future areas of practical and theoretical work are presented.

  10. NaviSE: superenhancer navigator integrating epigenomics signal algebra.

    Science.gov (United States)

    Ascensión, Alex M; Arrospide-Elgarresta, Mikel; Izeta, Ander; Araúzo-Bravo, Marcos J

    2017-06-06

    Superenhancers are crucial structural genomic elements determining cell fate, and they are also involved in the determination of several diseases, such as cancer or neurodegeneration. Although there are pipelines which use independent pieces of software to predict the presence of superenhancers from genome-wide chromatin marks or DNA-interaction protein binding sites, there is not yet an integrated software tool that processes automatically algebra combinations of raw data sequencing into a comprehensive final annotated report of predicted superenhancers. We have developed NaviSE, a user-friendly streamlined tool which performs a fully-automated parallel processing of genome-wide epigenomics data from sequencing files into a final report, built with a comprehensive set of annotated files that are navigated through a graphic user interface dynamically generated by NaviSE. NaviSE also implements an 'epigenomics signal algebra' that allows the combination of multiple activation and repression epigenomics signals. NaviSE provides an interactive chromosomal landscaping of the locations of superenhancers, which can be navigated to obtain annotated information about superenhancer signal profile, associated genes, gene ontology enrichment analysis, motifs of transcription factor binding sites enriched in superenhancers, graphs of the metrics evaluating the superenhancers quality, protein-protein interaction networks and enriched metabolic pathways among other features. We have parallelised the most time-consuming tasks achieving a reduction up to 30% for a 15 CPUs machine. We have optimized the default parameters of NaviSE to facilitate its use. NaviSE allows different entry levels of data processing, from sra-fastq files to bed files; and unifies the processing of multiple replicates. NaviSE outperforms the more time-consuming processes required in a non-integrated pipeline. Alongside its high performance, NaviSE is able to provide biological insights, predicting cell

  11. Navigation system for a mobile robot with a visual sensor using a fish-eye lens

    Science.gov (United States)

    Kurata, Junichi; Grattan, Kenneth T. V.; Uchiyama, Hironobu

    1998-02-01

    Various position sensing and navigation systems have been proposed for the autonomous control of mobile robots. Some of these systems have been installed with an omnidirectional visual sensor system that proved very useful in obtaining information on the environment around the mobile robot for position reckoning. In this article, this type of navigation system is discussed. The sensor is composed of one TV camera with a fish-eye lens, using a reference target on a ceiling and hybrid image processing circuits. The position of the robot, with respect to the floor, is calculated by integrating the information obtained from a visual sensor and a gyroscope mounted in the mobile robot, and the use of a simple algorithm based on PTP control for guidance is discussed. An experimental trial showed that the proposed system was both valid and useful for the navigation of an indoor vehicle.

  12. Application of image guidance in pituitary surgery

    Science.gov (United States)

    de Lara, Danielle; Filho, Leo F. S. Ditzel; Prevedello, Daniel M.; Otto, Bradley A.; Carrau, Ricardo L.

    2012-01-01

    Background: Surgical treatment of pituitary pathologies has evolved along the years, adding safety and decreasing morbidity related to the procedure. Advances in the field of radiology, coupled with stereotactic technology and computer modeling, have culminated in the contemporary and widespread use of image guidance systems, as we know them today. Image guidance navigation has become a frequently used technology that provides continuous three-dimensional information for the accurate performance of neurosurgical procedures. We present a discussion about the application of image guidance in pituitary surgeries. Methods: Major indications for image guidance neuronavigation application in pituitary surgery are presented and demonstrated with illustrative cases. Limitations of this technology are also presented. Results: Patients presenting a history of previous transsphenoidal surgeries, anatomical variances of the sphenoid sinus, tumors with a close relation to the internal carotid arteries, and extrasellar tumors are the most important indications for image guidance in pituitary surgeries. The high cost of the equipment, increased time of surgery due to setup time, and registration and the need of specific training for the operating room personnel could be pointed as limitations of this technology. Conclusion: Intraoperative image guidance systems provide real-time images, increasing surgical accuracy and enabling safe, minimally invasive interventions. However, the use of intraoperative navigation is not a replacement for surgical experience and a systematic knowledge of regional anatomy. It must be recognized as a tool by which the neurosurgeon can reduce the risk associated with surgical approach and treatment of pituitary pathologies. PMID:22826819

  13. Integrating GPS, GYRO, vehicle speed sensor, and digital map to provide accurate and real-time position in an intelligent navigation system

    Science.gov (United States)

    Li, Qingquan; Fang, Zhixiang; Li, Hanwu; Xiao, Hui

    2005-10-01

    The global positioning system (GPS) has become the most extensively used positioning and navigation tool in the world. Applications of GPS abound in surveying, mapping, transportation, agriculture, military planning, GIS, and the geosciences. However, the positional and elevation accuracy of any given GPS location is prone to error, due to a number of factors. The applications of Global Positioning System (GPS) positioning is more and more popular, especially the intelligent navigation system which relies on GPS and Dead Reckoning technology is developing quickly for future huge market in China. In this paper a practical combined positioning model of GPS/DR/MM is put forward, which integrates GPS, Gyro, Vehicle Speed Sensor (VSS) and digital navigation maps to provide accurate and real-time position for intelligent navigation system. This model is designed for automotive navigation system making use of Kalman filter to improve position and map matching veracity by means of filtering raw GPS and DR signals, and then map-matching technology is used to provide map coordinates for map displaying. In practical examples, for illustrating the validity of the model, several experiments and their results of integrated GPS/DR positioning in intelligent navigation system will be shown for the conclusion that Kalman Filter based GPS/DR integrating position approach is necessary, feasible and efficient for intelligent navigation application. Certainly, this combined positioning model, similar to other model, can not resolve all situation issues. Finally, some suggestions are given for further improving integrated GPS/DR/MM application.

  14. The Integration of GPS Navigator Device with Vehicles Tracking System for Rental Cars Firms

    OpenAIRE

    Omarah O. Alharaki; Fahad S. Alaieri; Akram M. Zeki

    2010-01-01

    The aim of this research is to integrate the GPS tracking system (tracking device and web-based application) with GPS navigator for rental cars, allowing the company to use various applications to monitor and manage the cars. This is enable the firms and customers to communicate with each other via the GPS navigator. The system should be developed by applying new features in GPS tracking application devices in vehicles. This paper also proposes new features that can be applied to the GPS Navi...

  15. Data Integration from GPS and Inertial Navigation Systems for Pedestrians in Urban Area

    Directory of Open Access Journals (Sweden)

    Krzysztof Bikonis

    2013-09-01

    Full Text Available The GPS system is widely used in navigation and the GPS receiver can offer long-term stable absolute positioning information. The overall system performance depends largely on the signal environments. The position obtained from GPS is often degraded due to obstruction and multipath effect caused by buildings, city infrastructure and vegetation, whereas, the current performance achieved by inertial navigation systems (INS is still relatively poor due to the large inertial sensor errors. The complementary features of GPS and INS are the main reasons why integrated GPS/INS systems are becoming increasingly popular. GPS/INS systems offer a high data rate, high accuracy position and orientation that can work in all environments, particularly those where satellite availability is restricted. In the paper integration algorithm of GPS and INS systems data for pedestrians in urban area is presented. For data integration an Extended Kalman Filter (EKF algorithm is proposed. Complementary characteristics of GPS and INS with EKF can overcome the problem of huge INS drifts, GPS outages, dense multipath effect and other individual problems associated with these sensors.

  16. IAE-adaptive Kalman filter for INS/GPS integrated navigation system

    Institute of Scientific and Technical Information of China (English)

    Bian Hongwei; Jin Zhihua; Tian Weifeng

    2006-01-01

    A marine INS/GPS adaptive navigation system is presented in this paper. GPS with two antenna providing vessel's altitude is selected as the auxiliary system fusing with INS to improve the performance of the hybrid system. The Kalman filter is the most frequently used algorithm in the integrated navigation system, which is capable of estimating INS errors online based on the measured errors between INS and GPS. The standard Kalman filter (SKF) assumes that the statistics of the noise on each sensor are given. As long as the noise distributions do not change, the Kalman filter will give the optimal estimation. However GPS receiver will be disturbed easily and thus temporally changing measurement noise will join into the outputs of GPS, which will lead to performance degradation of the Kalman filter. Many researchers introduce fuzzy logic control method into innovation-based adaptive estimation adaptive Kalman filtering (IAE-AKF) algorithm, and accordingly propose various adaptive Kalman filters. However how to design the fuzzy logic controller is a very complicated problem still without a convincing solution. A novel IAE-AKF is proposed herein, which is based on the maximum likelihood criterion for the proper computation of the filter innovation covariance and hence of the filter gain. The approach is direct and simple without having to establish fuzzy inference rules. After having deduced the proposed IAE-AKF algorithm theoretically in detail, the approach is tested by the simulation based on the system error model of the developed INS/GPS integrated marine navigation system. Simulation results show that the adaptive Kalman filter outperforms the SKF with higher accuracy, robustness and less computation. It is demonstrated that this proposed approach is a valid solution for the unknown changing measurement noise exited in the Kalman filter.

  17. Novel Navigation Algorithm for Wireless Sensor Networks without Information of Locations

    NARCIS (Netherlands)

    Guo, Peng; Jiang, Tao; Yi, Youwen; Zhang, Qian; Zhang, Kui

    2011-01-01

    In this paper, we propose a novel algorithm of distributed navigation for people to escape from critical event region in wireless sensor networks (WSNs). Unlike existing works, the scenario discussed in the paper has no goal or exit as guidance, leading to a big challenge for the navigation problem.

  18. Buried Waste Integrated Demonstration Technology Preparedness and Status Report Guidance

    International Nuclear Information System (INIS)

    Blacker, P.B.; Bonnenberg, R.W.; Cannon, P.G.; Hyde, R.A.; Watson, L.R.

    1994-04-01

    A Technology Preparedness and Status Report is required for each Technical Task Plan funded by the Buried Waste Integrated Demonstration. This document provides guidance for the preparation of that report. Major sections of the report will include a subset of the need for the technology, objectives of the demonstration, technology description and readiness evaluation, demonstration requirements, and preparedness checklist and action plan

  19. A joint mid-course and terminal course cooperative guidance law for multi-missile salvo attack

    Directory of Open Access Journals (Sweden)

    Jie ZENG

    2018-06-01

    Full Text Available Salvo attacking a surface target by multiple missiles is an effective tactic to enhance the lethality and penetrate the defense system. However, existing cooperative guidance laws in the mid-course or terminal course are not suitable for long- and medium-range missiles or stand-off attacking. Because the initial conditions of cooperative terminal guidance that are generally generated from the mid-course flight may not lead to a successful cooperative terminal guidance without proper mid-course flight adjustment. Meanwhile, cooperative guidance in the mid-course cannot solely guarantee the accuracy of a simultaneous arrival of multiple missiles. Therefore, a joint mid-course and terminal course cooperative guidance law is developed. By building a distinct leader-follower framework, this paper proposes an efficient coordinated Dubins path planning method to synchronize the arrival time of all engaged missiles in the mid-course flight. The planned flight can generate proper initial conditions for cooperative terminal guidance, and also benefit an earliest simultaneous arrival. In the terminal course, an existing cooperative proportional navigation guidance law guides all the engaged missiles to arrive at a target accurately and simultaneously. The integrated guidance law for an intuitive application is summarized. Simulations demonstrate that the proposed method can generate fast and accurate salvo attack. Keywords: Cooperative systems, Dubins path, Mid-course flight, Missile guidance, Salvo attack

  20. SU-F-P-42: “To Navigate, Or Not to Navigate: HDR BT in Recurrent Spine Lesions”

    Energy Technology Data Exchange (ETDEWEB)

    Voros, L; Cohen, G; Zaider, M; Yamada, Y [Memorial Sloan-Kettering Cancer Center, New York, NY (United States)

    2016-06-15

    Purpose: We compare the accuracy of HDR catheter placement for paraspinal lesions using O-arm CBCT imaging combined with StealthStation navigation and traditional fluoroscopically guided catheter placement. Methods: CT and MRI scans were acquired pre-treatment to outline the lesions and design treatment plans (pre-plans) to meet dosimetric constrains. The pre-planned catheter trajectories were transferred into the StealthStation Navigation system prior to the surgery. The StealthStation is an infra red (IR) optical navigation system used for guidance of surgical instruments. An intraoperative CBCT scan (O-arm) was acquired with reference IR optical fiducials anchored onto the patient and registered with the preplan image study to guide surgical instruments in relation to the patients’ anatomy and to place the brachytherapy catheters along the pre-planned trajectories. The final treatment plan was generated based on a 2nd intraoperative CBCT scan reflecting achieved implant geometry. The 2nd CBCT was later registered with the initial CT scan to compare the preplanned dwell positions with actual dwell positions (catheter placements). Similar workflow was used in placement of 8 catheters (1 patient) without navigation, but under fluoroscopy guidance in an interventional radiology suite. Results: A total of 18 catheters (3 patients) were placed using navigation assisted surgery. Average displacement of 0.66 cm (STD=0.37cm) was observed between the pre-plan source positions and actual source positions in the 3 dimensional space. This translates into an average 0.38 cm positioning error in one direction including registration errors, digitization errors, and the surgeons ability to follow the planned trajectory. In comparison, average displacement of non-navigated catheters was 0.50 cm (STD=0.22cm). Conclusion: Spinal lesion HDR brachytherapy planning is a difficult task. Catheter placement has a direct impact on target coverage and dose to critical structures. While

  1. A novel smart navigation system for intramedullary nailing in orthopedic surgery.

    Directory of Open Access Journals (Sweden)

    Jaesuk Choi

    Full Text Available This paper proposes a novel smart surgical navigation system for intramedullary nailing in orthopedic surgery. Using a handle-integrated laser guidance module, the system can target a drill insertion point onto skin, indicating an accurate target position to perpendicularly access an invisible distal hole. The proposed handle-integration-based fixation of the laser guidance module precisely defines the relative position of the module with respect to the distal hole. Consequently, unlike conventional systems, the proposed system can indicate the target insertion point without any help from bulky and costly external position-tracking equipment that is usually required for compensating disturbances generated by external impacts. After insertion, a correct drilling direction toward the distal hole is guided by real-time drilling angle measurement modules-one integrated with the nail handle and the other with the drill body. Each module contains a 9-axis inertial sensor and a Bluetooth communication device. These two modules work together to provide real-time drilling angle data, allowing calculation of the directional error toward the center of the distal hole in real time. The proposed system removes the need for fluoroscopy and provides a compact and cost-effective solution compared with conventional systems.

  2. In-motion initial alignment and positioning with INS/CNS/ODO integrated navigation system for lunar rovers

    Science.gov (United States)

    Lu, Jiazhen; Lei, Chaohua; Yang, Yanqiang; Liu, Ming

    2017-06-01

    Many countries have been paying great attention to space exploration, especially about the Moon and the Mars. Autonomous and high-accuracy navigation systems are needed for probers and rovers to accomplish missions. Inertial navigation system (INS)/celestial navigation system (CNS) based navigation system has been used widely on the lunar rovers. Initialization is a particularly important step for navigation. This paper presents an in-motion alignment and positioning method for lunar rovers by INS/CNS/odometer integrated navigation. The method can estimate not only the position and attitude errors, but also the biases of the accelerometers and gyros using the standard Kalman filter. The differences between the platform star azimuth, elevation angles and the computed star azimuth, elevation angles, and the difference between the velocity measured by odometer and the velocity measured by inertial sensors are taken as measurements. The semi-physical experiments are implemented to demonstrate that the position error can reduce to 10 m and attitude error is within 2″ during 5 min. The experiment results prove that it is an effective and attractive initialization approach for lunar rovers.

  3. Integration of Kinect and Low-Cost Gnss for Outdoor Navigation

    Science.gov (United States)

    Pagliaria, D.; Pinto, L.; Reguzzoni, M.; Rossi, L.

    2016-06-01

    Since its launch on the market, Microsoft Kinect sensor has represented a great revolution in the field of low cost navigation, especially for indoor robotic applications. In fact, this system is endowed with a depth camera, as well as a visual RGB camera, at a cost of about 200. The characteristics and the potentiality of the Kinect sensor have been widely studied for indoor applications. The second generation of this sensor has been announced to be capable of acquiring data even outdoors, under direct sunlight. The task of navigating passing from an indoor to an outdoor environment (and vice versa) is very demanding because the sensors that work properly in one environment are typically unsuitable in the other one. In this sense the Kinect could represent an interesting device allowing bridging the navigation solution between outdoor and indoor. In this work the accuracy and the field of application of the new generation of Kinect sensor have been tested outdoor, considering different lighting conditions and the reflective properties of the emitted ray on different materials. Moreover, an integrated system with a low cost GNSS receiver has been studied, with the aim of taking advantage of the GNSS positioning when the satellite visibility conditions are good enough. A kinematic test has been performed outdoor by using a Kinect sensor and a GNSS receiver and it is here presented.

  4. A New Adaptive H-Infinity Filtering Algorithm for the GPS/INS Integrated Navigation

    Science.gov (United States)

    Jiang, Chen; Zhang, Shu-Bi; Zhang, Qiu-Zhao

    2016-01-01

    The Kalman filter is an optimal estimator with numerous applications in technology, especially in systems with Gaussian distributed noise. Moreover, the adaptive Kalman filtering algorithms, based on the Kalman filter, can control the influence of dynamic model errors. In contrast to the adaptive Kalman filtering algorithms, the H-infinity filter is able to address the interference of the stochastic model by minimization of the worst-case estimation error. In this paper, a novel adaptive H-infinity filtering algorithm, which integrates the adaptive Kalman filter and the H-infinity filter in order to perform a comprehensive filtering algorithm, is presented. In the proposed algorithm, a robust estimation method is employed to control the influence of outliers. In order to verify the proposed algorithm, experiments with real data of the Global Positioning System (GPS) and Inertial Navigation System (INS) integrated navigation, were conducted. The experimental results have shown that the proposed algorithm has multiple advantages compared to the other filtering algorithms. PMID:27999361

  5. A projective surgical navigation system for cancer resection

    Science.gov (United States)

    Gan, Qi; Shao, Pengfei; Wang, Dong; Ye, Jian; Zhang, Zeshu; Wang, Xinrui; Xu, Ronald

    2016-03-01

    Near infrared (NIR) fluorescence imaging technique can provide precise and real-time information about tumor location during a cancer resection surgery. However, many intraoperative fluorescence imaging systems are based on wearable devices or stand-alone displays, leading to distraction of the surgeons and suboptimal outcome. To overcome these limitations, we design a projective fluorescence imaging system for surgical navigation. The system consists of a LED excitation light source, a monochromatic CCD camera, a host computer, a mini projector and a CMOS camera. A software program is written by C++ to call OpenCV functions for calibrating and correcting fluorescence images captured by the CCD camera upon excitation illumination of the LED source. The images are projected back to the surgical field by the mini projector. Imaging performance of this projective navigation system is characterized in a tumor simulating phantom. Image-guided surgical resection is demonstrated in an ex-vivo chicken tissue model. In all the experiments, the projected images by the projector match well with the locations of fluorescence emission. Our experimental results indicate that the proposed projective navigation system can be a powerful tool for pre-operative surgical planning, intraoperative surgical guidance, and postoperative assessment of surgical outcome. We have integrated the optoelectronic elements into a compact and miniaturized system in preparation for further clinical validation.

  6. Navigation and Robotics in Spinal Surgery: Where Are We Now?

    Science.gov (United States)

    Overley, Samuel C; Cho, Samuel K; Mehta, Ankit I; Arnold, Paul M

    2017-03-01

    Spine surgery has experienced much technological innovation over the past several decades. The field has seen advancements in operative techniques, implants and biologics, and equipment such as computer-assisted navigation and surgical robotics. With the arrival of real-time image guidance and navigation capabilities along with the computing ability to process and reconstruct these data into an interactive three-dimensional spinal "map", so too have the applications of surgical robotic technology. While spinal robotics and navigation represent promising potential for improving modern spinal surgery, it remains paramount to demonstrate its superiority as compared to traditional techniques prior to assimilation of its use amongst surgeons.The applications for intraoperative navigation and image-guided robotics have expanded to surgical resection of spinal column and intradural tumors, revision procedures on arthrodesed spines, and deformity cases with distorted anatomy. Additionally, these platforms may mitigate much of the harmful radiation exposure in minimally invasive surgery to which the patient, surgeon, and ancillary operating room staff are subjected.Spine surgery relies upon meticulous fine motor skills to manipulate neural elements and a steady hand while doing so, often exploiting small working corridors utilizing exposures that minimize collateral damage. Additionally, the procedures may be long and arduous, predisposing the surgeon to both mental and physical fatigue. In light of these characteristics, spine surgery may actually be an ideal candidate for the integration of navigation and robotic-assisted procedures.With this paper, we aim to critically evaluate the current literature and explore the options available for intraoperative navigation and robotic-assisted spine surgery. Copyright © 2016 by the Congress of Neurological Surgeons.

  7. Real-time Pedestrian Crossing Recognition for Assistive Outdoor Navigation.

    Science.gov (United States)

    Fontanesi, Simone; Frigerio, Alessandro; Fanucci, Luca; Li, William

    2015-01-01

    Navigation in urban environments can be difficult for people who are blind or visually impaired. In this project, we present a system and algorithms for recognizing pedestrian crossings in outdoor environments. Our goal is to provide navigation cues for crossing the street and reaching an island or sidewalk safely. Using a state-of-the-art Multisense S7S sensor, we collected 3D pointcloud data for real-time detection of pedestrian crossing and generation of directional guidance. We demonstrate improvements to a baseline, monocular-camera-based system by integrating 3D spatial prior information extracted from the pointcloud. Our system's parameters can be set to the actual dimensions of real-world settings, which enables robustness of occlusion and perspective transformation. The system works especially well in non-occlusion situations, and is reasonably accurate under different kind of conditions. As well, our large dataset of pedestrian crossings, organized by different types and situations of pedestrian crossings in order to reflect real-word environments, is publicly available in a commonly used format (ROS bagfiles) for further research.

  8. In silico Interrogation of Insect Central Complex Suggests Computational Roles for the Ellipsoid Body in Spatial Navigation

    Directory of Open Access Journals (Sweden)

    Vincenzo G. Fiore

    2017-08-01

    Full Text Available The central complex in the insect brain is a composite of midline neuropils involved in processing sensory cues and mediating behavioral outputs to orchestrate spatial navigation. Despite recent advances, however, the neural mechanisms underlying sensory integration and motor action selections have remained largely elusive. In particular, it is not yet understood how the central complex exploits sensory inputs to realize motor functions associated with spatial navigation. Here we report an in silico interrogation of central complex-mediated spatial navigation with a special emphasis on the ellipsoid body. Based on known connectivity and function, we developed a computational model to test how the local connectome of the central complex can mediate sensorimotor integration to guide different forms of behavioral outputs. Our simulations show integration of multiple sensory sources can be effectively performed in the ellipsoid body. This processed information is used to trigger continuous sequences of action selections resulting in self-motion, obstacle avoidance and the navigation of simulated environments of varying complexity. The motor responses to perceived sensory stimuli can be stored in the neural structure of the central complex to simulate navigation relying on a collective of guidance cues, akin to sensory-driven innate or habitual behaviors. By comparing behaviors under different conditions of accessible sources of input information, we show the simulated insect computes visual inputs and body posture to estimate its position in space. Finally, we tested whether the local connectome of the central complex might also allow the flexibility required to recall an intentional behavioral sequence, among different courses of actions. Our simulations suggest that the central complex can encode combined representations of motor and spatial information to pursue a goal and thus successfully guide orientation behavior. Together, the observed

  9. In silico Interrogation of Insect Central Complex Suggests Computational Roles for the Ellipsoid Body in Spatial Navigation.

    Science.gov (United States)

    Fiore, Vincenzo G; Kottler, Benjamin; Gu, Xiaosi; Hirth, Frank

    2017-01-01

    The central complex in the insect brain is a composite of midline neuropils involved in processing sensory cues and mediating behavioral outputs to orchestrate spatial navigation. Despite recent advances, however, the neural mechanisms underlying sensory integration and motor action selections have remained largely elusive. In particular, it is not yet understood how the central complex exploits sensory inputs to realize motor functions associated with spatial navigation. Here we report an in silico interrogation of central complex-mediated spatial navigation with a special emphasis on the ellipsoid body. Based on known connectivity and function, we developed a computational model to test how the local connectome of the central complex can mediate sensorimotor integration to guide different forms of behavioral outputs. Our simulations show integration of multiple sensory sources can be effectively performed in the ellipsoid body. This processed information is used to trigger continuous sequences of action selections resulting in self-motion, obstacle avoidance and the navigation of simulated environments of varying complexity. The motor responses to perceived sensory stimuli can be stored in the neural structure of the central complex to simulate navigation relying on a collective of guidance cues, akin to sensory-driven innate or habitual behaviors. By comparing behaviors under different conditions of accessible sources of input information, we show the simulated insect computes visual inputs and body posture to estimate its position in space. Finally, we tested whether the local connectome of the central complex might also allow the flexibility required to recall an intentional behavioral sequence, among different courses of actions. Our simulations suggest that the central complex can encode combined representations of motor and spatial information to pursue a goal and thus successfully guide orientation behavior. Together, the observed computational features

  10. A new guidance law for a tactical surface-to-surface missile

    Directory of Open Access Journals (Sweden)

    Danilo V. Ćuk

    2012-01-01

    Full Text Available Modern tactical surface-to-surface missiles, equipped with strapdown inertial navigation systems, achieve very good accuracy compared with free-flight rockets. The probable range dispersion mainly depends on instruments errors and longitudinal disturbances such as rocket motor total-impulse deviation as well as differences between the estimated and actual values of the axial force and head wind. This paper gives an extension of the correlated velocity concept for surface-to-surface missiles without a thrust-terminating mechanism. The calculated parameters of the correlated velocity are stored into the memory of an onboard guidance computer. On the basis of the correlated velocity concept, the modified proportional navigation with the adjustment of the time-to-go of the missile to the target was proposed. It is shown that the new guidance law can compensate for the longitudinal disturbances of different levels successfully. The effectiveness of the proposed guidance method was confirmed by means of the calculated probable range and lateral dispersion for the anticipated disturbances in the guidance system.

  11. SLS Model Based Design: A Navigation Perspective

    Science.gov (United States)

    Oliver, T. Emerson; Anzalone, Evan; Park, Thomas; Geohagan, Kevin

    2018-01-01

    The SLS Program has implemented a Model-based Design (MBD) and Model-based Requirements approach for managing component design information and system requirements. This approach differs from previous large-scale design efforts at Marshall Space Flight Center where design documentation alone conveyed information required for vehicle design and analysis and where extensive requirements sets were used to scope and constrain the design. The SLS Navigation Team is responsible for the Program-controlled Design Math Models (DMMs) which describe and represent the performance of the Inertial Navigation System (INS) and the Rate Gyro Assemblies (RGAs) used by Guidance, Navigation, and Controls (GN&C). The SLS Navigation Team is also responsible for navigation algorithms. The navigation algorithms are delivered for implementation on the flight hardware as a DMM. For the SLS Block 1B design, the additional GPS Receiver hardware model is managed as a DMM at the vehicle design level. This paper describes the models, and discusses the processes and methods used to engineer, design, and coordinate engineering trades and performance assessments using SLS practices as applied to the GN&C system, with a particular focus on the navigation components.

  12. An adaptive reentry guidance method considering the influence of blackout zone

    Science.gov (United States)

    Wu, Yu; Yao, Jianyao; Qu, Xiangju

    2018-01-01

    Reentry guidance has been researched as a popular topic because it is critical for a successful flight. In view that the existing guidance methods do not take into account the accumulated navigation error of Inertial Navigation System (INS) in the blackout zone, in this paper, an adaptive reentry guidance method is proposed to obtain the optimal reentry trajectory quickly with the target of minimum aerodynamic heating rate. The terminal error in position and attitude can be also reduced with the proposed method. In this method, the whole reentry guidance task is divided into two phases, i.e., the trajectory updating phase and the trajectory planning phase. In the first phase, the idea of model predictive control (MPC) is used, and the receding optimization procedure ensures the optimal trajectory in the next few seconds. In the trajectory planning phase, after the vehicle has flown out of the blackout zone, the optimal reentry trajectory is obtained by online planning to adapt to the navigation information. An effective swarm intelligence algorithm, i.e. pigeon inspired optimization (PIO) algorithm, is applied to obtain the optimal reentry trajectory in both of the two phases. Compared to the trajectory updating method, the proposed method can reduce the terminal error by about 30% considering both the position and attitude, especially, the terminal error of height has almost been eliminated. Besides, the PIO algorithm performs better than the particle swarm optimization (PSO) algorithm both in the trajectory updating phase and the trajectory planning phases.

  13. Tightly coupled low cost 3D RISS/GPS integration using a mixture particle filter for vehicular navigation.

    Science.gov (United States)

    Georgy, Jacques; Noureldin, Aboelmagd

    2011-01-01

    Satellite navigation systems such as the global positioning system (GPS) are currently the most common technique used for land vehicle positioning. However, in GPS-denied environments, there is an interruption in the positioning information. Low-cost micro-electro mechanical system (MEMS)-based inertial sensors can be integrated with GPS and enhance the performance in denied GPS environments. The traditional technique for this integration problem is Kalman filtering (KF). Due to the inherent errors of low-cost MEMS inertial sensors and their large stochastic drifts, KF, with its linearized models, has limited capabilities in providing accurate positioning. Particle filtering (PF) was recently suggested as a nonlinear filtering technique to accommodate for arbitrary inertial sensor characteristics, motion dynamics and noise distributions. An enhanced version of PF called the Mixture PF is utilized in this study to perform tightly coupled integration of a three dimensional (3D) reduced inertial sensors system (RISS) with GPS. In this work, the RISS consists of one single-axis gyroscope and a two-axis accelerometer used together with the vehicle's odometer to obtain 3D navigation states. These sensors are then integrated with GPS in a tightly coupled scheme. In loosely-coupled integration, at least four satellites are needed to provide acceptable GPS position and velocity updates for the integration filter. The advantage of the tightly-coupled integration is that it can provide GPS measurement update(s) even when the number of visible satellites is three or lower, thereby improving the operation of the navigation system in environments with partial blockages by providing continuous aiding to the inertial sensors even during limited GPS satellite availability. To effectively exploit the capabilities of PF, advanced modeling for the stochastic drift of the vertically aligned gyroscope is used. In order to benefit from measurement updates for such drift, which are

  14. Tightly Coupled Low Cost 3D RISS/GPS Integration Using a Mixture Particle Filter for Vehicular Navigation

    Directory of Open Access Journals (Sweden)

    Jacques Georgy

    2011-04-01

    Full Text Available Satellite navigation systems such as the global positioning system (GPS are currently the most common technique used for land vehicle positioning. However, in GPS-denied environments, there is an interruption in the positioning information. Low-cost micro-electro mechanical system (MEMS-based inertial sensors can be integrated with GPS and enhance the performance in denied GPS environments. The traditional technique for this integration problem is Kalman filtering (KF. Due to the inherent errors of low-cost MEMS inertial sensors and their large stochastic drifts, KF, with its linearized models, has limited capabilities in providing accurate positioning. Particle filtering (PF was recently suggested as a nonlinear filtering technique to accommodate for arbitrary inertial sensor characteristics, motion dynamics and noise distributions. An enhanced version of PF called the Mixture PF is utilized in this study to perform tightly coupled integration of a three dimensional (3D reduced inertial sensors system (RISS with GPS. In this work, the RISS consists of one single-axis gyroscope and a two-axis accelerometer used together with the vehicle’s odometer to obtain 3D navigation states. These sensors are then integrated with GPS in a tightly coupled scheme. In loosely-coupled integration, at least four satellites are needed to provide acceptable GPS position and velocity updates for the integration filter. The advantage of the tightly-coupled integration is that it can provide GPS measurement update(s even when the number of visible satellites is three or lower, thereby improving the operation of the navigation system in environments with partial blockages by providing continuous aiding to the inertial sensors even during limited GPS satellite availability. To effectively exploit the capabilities of PF, advanced modeling for the stochastic drift of the vertically aligned gyroscope is used. In order to benefit from measurement updates for such drift

  15. Parsimonious Ways to Use Vision for Navigation

    Directory of Open Access Journals (Sweden)

    Paul Graham

    2012-05-01

    Full Text Available The use of visual information for navigation appears to be a universal strategy for sighted animals, amongst which, one particular group of expert navigators are the ants. The broad interest in studies of ant navigation is in part due to their small brains, thus biomimetic engineers expect to be impressed by elegant control solutions, and psychologists might hope for a description of the minimal cognitive requirements for complex spatial behaviours. In this spirit, we have been taking an interdisciplinary approach to the visual guided navigation of ants in their natural habitat. Behavioural experiments and natural image statistics show that visual navigation need not depend on the remembering or recognition of objects. Further modelling work suggests how simple behavioural routines might enable navigation using familiarity detection rather than explicit recall, and we present a proof of concept that visual navigation using familiarity can be achieved without specifying when or what to learn, nor separating routes into sequences of waypoints. We suggest that our current model represents the only detailed and complete model of insect route guidance to date. What's more, we believe the suggested mechanisms represent useful parsimonious hypotheses for the visually guided navigation in larger-brain animals.

  16. Robust Pedestrian Navigation for Challenging Applications

    OpenAIRE

    Gilliéron, PY; Renaudin, V

    2009-01-01

    Presentation of a concept for robust indoor navigation. The concept is based on three key elements: - the use of an absolute geographical reference - the hybridisation of complementary technologies - specific motion models. This concept is illustrated by the means of two applications: the urban displacement of blind people and the indoor guidance of fire-fighters

  17. An integrated autonomous rendezvous and docking system architecture using Centaur modern avionics

    Science.gov (United States)

    Nelson, Kurt

    1991-01-01

    The avionics system for the Centaur upper stage is in the process of being modernized with the current state-of-the-art in strapdown inertial guidance equipment. This equipment includes an integrated flight control processor with a ring laser gyro based inertial guidance system. This inertial navigation unit (INU) uses two MIL-STD-1750A processors and communicates over the MIL-STD-1553B data bus. Commands are translated into load activation through a Remote Control Unit (RCU) which incorporates the use of solid state relays. Also, a programmable data acquisition system replaces separate multiplexer and signal conditioning units. This modern avionics suite is currently being enhanced through independent research and development programs to provide autonomous rendezvous and docking capability using advanced cruise missile image processing technology and integrated GPS navigational aids. A system concept was developed to combine these technologies in order to achieve a fully autonomous rendezvous, docking, and autoland capability. The current system architecture and the evolution of this architecture using advanced modular avionics concepts being pursued for the National Launch System are discussed.

  18. Navigated MRI-guided liver biopsies in a closed-bore scanner: experience in 52 patients.

    Science.gov (United States)

    Moche, Michael; Heinig, Susann; Garnov, Nikita; Fuchs, Jochen; Petersen, Tim-Ole; Seider, Daniel; Brandmaier, Philipp; Kahn, Thomas; Busse, Harald

    2016-08-01

    To evaluate clinical effectiveness and diagnostic efficiency of a navigation device for MR-guided biopsies of focal liver lesions in a closed-bore scanner. In 52 patients, 55 biopsies were performed. An add-on MR navigation system with optical instrument tracking was used for image guidance and biopsy device insertion outside the bore. Fast control imaging allowed visualization of the true needle position at any time. The biopsy workflow and procedure duration were recorded. Histological analysis and clinical course/outcome were used to calculate sensitivity, specificity and diagnostic accuracy. Fifty-four of 55 liver biopsies were performed successfully with the system. No major and four minor complications occurred. Mean tumour size was 23 ± 14 mm and the skin-to-target length ranged from 22 to 177 mm. In 39 cases, access path was double oblique. Sensitivity, specificity and diagnostic accuracy were 88 %, 100 % and 92 %, respectively. The mean procedure time was 51 ± 12 min, whereas the puncture itself lasted 16 ± 6 min. On average, four control scans were taken. Using this navigation device, biopsies of poorly visible and difficult accessible liver lesions could be performed safely and reliably in a closed-bore MRI scanner. The system can be easily implemented in clinical routine workflow. • Targeted liver biopsies could be reliably performed in a closed-bore MRI. • The navigation system allows for image guidance outside of the scanner bore. • Assisted MRI-guided biopsies are helpful for focal lesions with a difficult access. • Successful integration of the method in clinical workflow was shown. • Subsequent system installation in an existing MRI environment is feasible.

  19. Navigating the National Qualifications Framework (NQF): The role of ...

    African Journals Online (AJOL)

    Navigating the National Qualifications Framework (NQF): The role of career guidance. ... opportunities (including, but not confined to, those within higher education). ... It argues that the time is ripe for a high-level national career development ...

  20. A Three-Dimensional Cooperative Guidance Law of Multimissile System

    Directory of Open Access Journals (Sweden)

    Xing Wei

    2015-01-01

    Full Text Available In order to conduct saturation attacks on a static target, the cooperative guidance problem of multimissile system is researched. A three-dimensional guidance model is built using vector calculation and the classic proportional navigation guidance (PNG law is extended to three dimensions. Based on this guidance law, a distributed cooperative guidance strategy is proposed and a consensus protocol is designed to coordinate the time-to-go commands of all missiles. Then an expert system, which contains two extreme learning machines (ELM, is developed to regulate the local proportional coefficient of each missile according to the command. All missiles can arrive at the target simultaneously under the assumption that the multimissile network is connected. A simulation scenario is given to demonstrate the validity of the proposed method.

  1. Image navigation as a means to expand the boundaries of fluorescence-guided surgery.

    Science.gov (United States)

    Brouwer, Oscar R; Buckle, Tessa; Bunschoten, Anton; Kuil, Joeri; Vahrmeijer, Alexander L; Wendler, Thomas; Valdés-Olmos, Renato A; van der Poel, Henk G; van Leeuwen, Fijs W B

    2012-05-21

    Hybrid tracers that are both radioactive and fluorescent help extend the use of fluorescence-guided surgery to deeper structures. Such hybrid tracers facilitate preoperative surgical planning using (3D) scintigraphic images and enable synchronous intraoperative radio- and fluorescence guidance. Nevertheless, we previously found that improved orientation during laparoscopic surgery remains desirable. Here we illustrate how intraoperative navigation based on optical tracking of a fluorescence endoscope may help further improve the accuracy of hybrid surgical guidance. After feeding SPECT/CT images with an optical fiducial as a reference target to the navigation system, optical tracking could be used to position the tip of the fluorescence endoscope relative to the preoperative 3D imaging data. This hybrid navigation approach allowed us to accurately identify marker seeds in a phantom setup. The multispectral nature of the fluorescence endoscope enabled stepwise visualization of the two clinically approved fluorescent dyes, fluorescein and indocyanine green. In addition, the approach was used to navigate toward the prostate in a patient undergoing robot-assisted prostatectomy. Navigation of the tracked fluorescence endoscope toward the target identified on SPECT/CT resulted in real-time gradual visualization of the fluorescent signal in the prostate, thus providing an intraoperative confirmation of the navigation accuracy.

  2. Relative navigation and attitude determination using a GPS/INS integrated system near the International Space Station

    Science.gov (United States)

    Um, Jaeyong

    2001-08-01

    The Space Integrated GPS/INS (SIGI) sensor is the primary navigation and attitude determination source for the International Space Station (ISS). The SIGI was successfully demonstrated on-orbit for the first time in the SIGI Orbital Attitude Readiness (SOAR) demonstration on the Space Shuttle Atlantis in May 2000. Numerous proximity operations near the ISS have been and will be performed over the lifetime of the Station. The development of an autonomous relative navigation system is needed to improve the safety and efficiency of vehicle operations near the ISS. A hardware simulation study was performed for the GPS-based relative navigation using the state vector difference approach and the interferometric approach in the absence of multipath. The interferometric approach, where the relative states are estimated directly, showed comparable results for a 1 km baseline. One of the most pressing current technical issues is the design of an autonomous relative navigation system in the proximity of the ISS, where GPS signals are blocked and maneuvers happen frequently. An integrated GPS/INS system is investigated for the possibility of a fully autonomous relative navigation system. Another application of GPS measurements is determination of the vehicle's orientation in space. This study used the SOAR experiment data to characterize the SICI's on-orbit performance for attitude determination. A cold start initialization algorithm was developed for integer ambiguity resolution in any initial orientation. The original algorithm that was used in the SIGI had an operational limitation in the integer ambiguity resolution, which was developed for terrestrial applications, and limited its effectiveness in space. The new algorithm was tested using the SOAR data and has been incorporated in the current SIGI flight software. The attitude estimation performance was examined using two different GPS/INS integration algorithms. The GPS/INS attitude solution using the SOAR data was as

  3. Fourth Integrated Communications, Navigation, and Surveillance (ICNS) Conference and Workshop 2004: Conclusions and Recommendations

    Science.gov (United States)

    Phillips, Brent; Swanda, Ronald L.; Lewis, Michael S.; Kenagy, Randy; Donahue, George; Homans, Al; Kerczewski, Robert; Pozesky, Marty

    2004-01-01

    The NASA Glenn Research Center organized and hosted the Fourth Integrated Communications, Navigation, and Surveillance (ICNS) Technologies Conference and Workshop, which took place April 26-30, 2004 at the Hyatt Fair Lakes Hotel in Fairfax, Virginia. This fourth conference of the annual series followed the very successful first ICNS Conference (May 1-3, 2001 in Cleveland, Ohio), second ICNS conference (April 29-May 2, 2002 in Vienna, Virginia), and third ICNS conference (May 19-22, 2003 in Annapolis, Maryland). The purpose of the Fourth ICNS Conference was to assemble government, industry and academic communities performing research and development for advanced digital communications, surveillance and navigation systems and associated applications supporting the national and global air transportation systems to: 1) Understand current efforts and recent results in near- and far-term R&D and technology demonstration; 2) Identify integrated digital communications, navigation and surveillance R&D requirements necessary for a safe, secure and reliable, high-capacity, advanced air transportation system; 3) Provide a forum for fostering collaboration and coordination; and 4) Discuss critical issues and develop recommendations to achieve the future integrated CNS vision for national and global air transportation. The workshop attracted 316 attendees from government, industry and academia to address these purposes through technical presentations, breakout sessions, and individual and group discussions during the workshop and after-hours events, and included 16 international attendees. An Executive Committee consisting of representatives of several key segments of the aviation community concerned with CNS issues met on the day following the workshop to consider the primary outcomes and recommendations of the workshop. This report presents an overview of the conference, workshop breakout session results, and the findings of the Executive Committee.

  4. INTEGRATION OF DISTRIBUTED INERTIAL NAVIGATION SYSTEMS BUILT AROUND FIBER-OPTIC AND MICROELECTROMECHANICAL SENSORS

    Directory of Open Access Journals (Sweden)

    A. V. Chernodarov

    2017-01-01

    Full Text Available The current state of airborne measuring-and-computing complexes (MCCs is characterized by the inclusion of distributed strapdown inertial navigation systems (SINSs as components of these complexes. This is associated with the necessity of the provision of navigational support not only for aircraft (Acft, but also for airborne Earth surface surveillance systems in which the SINSs are included as components. Among such systems are radar systems, video monitors, laser scanners (lidars, and other surveillance devices. At the same time, when the DSINSs are united into a single structure, new functional possibilities for such integrated navigation systems appear, namely: redundancy and mutual support of SINSs, and also an increase in MCC information reliability on this basis; mutual monitoring and mutual diagnosis of SINSs; optimization of DSINS structure for providing the required accuracy of navigation and attitude control under severe conditions of Acft operation. Such conditions are connected with Acft maneuvering, with a loss of the signals of satellite navigation systems (SNSs. The purpose of this paper is to study the capabilities of DSINS which are built around fiberoptic and micromechanical sensors when they are united into a closely connected information-measuring structure. In the solution of the problem formulated above, an object-oriented modular technology for the creation of integrated navigation systems was taken as a basis. The use of such a technology has permitted us to realize the new functional possibilities of the DSINSs, and also to take into account the following features of the construction and functioning of DSINSs as components of MCCs: need for mutual information exchange among DSINS modules via an MCC airborne top-level computing system; synchronization of measuring-and-computing procedures that are realized in the DSINS. In addition, due to restrictions on overall dimensions and weight, SINSs of surveillance systems are

  5. Integrated Navigation System Design for Micro Planetary Rovers: Comparison of Absolute Heading Estimation Algorithms and Nonlinear Filtering

    Science.gov (United States)

    Ilyas, Muhammad; Hong, Beomjin; Cho, Kuk; Baeg, Seung-Ho; Park, Sangdeok

    2016-01-01

    This paper provides algorithms to fuse relative and absolute microelectromechanical systems (MEMS) navigation sensors, suitable for micro planetary rovers, to provide a more accurate estimation of navigation information, specifically, attitude and position. Planetary rovers have extremely slow speed (~1 cm/s) and lack conventional navigation sensors/systems, hence the general methods of terrestrial navigation may not be applicable to these applications. While relative attitude and position can be tracked in a way similar to those for ground robots, absolute navigation information is hard to achieve on a remote celestial body, like Moon or Mars, in contrast to terrestrial applications. In this study, two absolute attitude estimation algorithms were developed and compared for accuracy and robustness. The estimated absolute attitude was fused with the relative attitude sensors in a framework of nonlinear filters. The nonlinear Extended Kalman filter (EKF) and Unscented Kalman filter (UKF) were compared in pursuit of better accuracy and reliability in this nonlinear estimation problem, using only on-board low cost MEMS sensors. Experimental results confirmed the viability of the proposed algorithms and the sensor suite, for low cost and low weight micro planetary rovers. It is demonstrated that integrating the relative and absolute navigation MEMS sensors reduces the navigation errors to the desired level. PMID:27223293

  6. A New Algorithm for ABS/GPS Integration Based on Fuzzy-Logic in Vehicle Navigation System

    Directory of Open Access Journals (Sweden)

    Ali Amin Zadeh

    2011-10-01

    Full Text Available GPS based vehicle navigation systems have difficulties in tracking vehicles in urban canyons due to poor satellite availability. ABS (Antilock Brake System Navigation System consists of self-contained optical encoders mounted on vehicle wheels that can continuously provide accurate short-term positioning information. In this paper, a new concept regarding GPS/ABS integration, based on Fuzzy Logic is presented. The proposed algorithm is used to identify GPS position accuracy based on environment and vehicle dynamic knowledge. The GPS is used as reference during the time it is in a good condition and replaced by ABS positioning system when GPS information is unreliable. We compare our proposed algorithm with other common algorithm in real environment. Our results show that the proposed algorithm can significantly improve the stability and reliability of ABS/GPS navigation system.

  7. ULTOR(Registered TradeMark) Passive Pose and Position Engine For Spacecraft Relative Navigation

    Science.gov (United States)

    Hannah, S. Joel

    2008-01-01

    The ULTOR(Registered TradeMark) Passive Pose and Position Engine (P3E) technology, developed by Advanced Optical Systems, Inc (AOS), uses real-time image correlation to provide relative position and pose data for spacecraft guidance, navigation, and control. Potential data sources include a wide variety of sensors, including visible and infrared cameras. ULTOR(Registered TradeMark) P3E has been demonstrated on a number of host processing platforms. NASA is integrating ULTOR(Registerd TradeMark) P3E into its Relative Navigation System (RNS), which is being developed for the upcoming Hubble Space Telescope (HST) Servicing Mission 4 (SM4). During SM4 ULTOR(Registered TradeMark) P3E will perform realtime pose and position measurements during both the approach and departure phases of the mission. This paper describes the RNS implementation of ULTOR(Registered TradeMark) P3E, and presents results from NASA's hardware-in-the-loop simulation testing against the HST mockup.

  8. Intraoperative computed tomography with an integrated navigation system in stabilization surgery for complex craniovertebral junction malformation.

    Science.gov (United States)

    Yu, Xinguang; Li, Lianfeng; Wang, Peng; Yin, Yiheng; Bu, Bo; Zhou, Dingbiao

    2014-07-01

    This study was designed to report our preliminary experience with stabilization procedures for complex craniovertebral junction malformation (CVJM) using intraoperative computed tomography (iCT) with an integrated neuronavigation system (NNS). To evaluate the workflow, feasibility and clinical outcome of stabilization procedures using iCT image-guided navigation for complex CVJM. The stabilization procedures in CVJM are complex because of the area's intricate geometry and bony structures, its critical relationship to neurovascular structures and the intricate biomechanical issues involved. A sliding gantry 40-slice computed tomography scanner was installed in a preexisting operating room. The images were transferred directly from the scanner to the NNS using an automated registration system. On the basis of the analysis of intraoperative computed tomographic images, 23 cases (11 males, 12 females) with complicated CVJM underwent navigated stabilization procedures to allow more control over screw placement. The age of these patients were 19-52 years (mean: 33.5 y). We performed C1-C2 transarticular screw fixation in 6 patients to produce atlantoaxial arthrodesis with better reliability. Because of a high-riding transverse foramen on at least 1 side of the C2 vertebra and an anomalous vertebral artery position, 7 patients underwent C1 lateral mass and C2 pedicle screw fixation. Ten additional patients were treated with individualized occipitocervical fixation surgery from the hypoplasia of C1 or constraints due to C2 bone structure. In total, 108 screws were inserted into 23 patients using navigational assistance. The screws comprised 20 C1 lateral mass screws, 26 C2, 14 C3, or 4 C4 pedicle screws, 32 occipital screws, and 12 C1-C2 transarticular screws. There were no vascular or neural complications except for pedicle perforations that were detected in 2 (1.9%) patients and were corrected intraoperatively without any persistent nerves or vessel damage. The overall

  9. Real-time 3-dimensional virtual reality navigation system with open MRI for breast-conserving surgery

    International Nuclear Information System (INIS)

    Tomikawa, Morimasa; Konishi, Kozo; Ieiri, Satoshi; Hong, Jaesung; Uemura, Munenori; Hashizume, Makoto; Shiotani, Satoko; Tokunaga, Eriko; Maehara, Yoshihiko

    2011-01-01

    We report here the early experiences using a real-time three-dimensional (3D) virtual reality navigation system with open magnetic resonance imaging (MRI) for breast-conserving surgery (BCS). Two patients with a non-palpable MRI-detected breast tumor underwent BCS under the guidance of the navigation system. An initial MRI for the breast tumor using skin-affixed markers was performed immediately prior to excision. A percutaneous intramammary dye marker was applied to delineate an excision line, and the computer software '3D Slicer' generated a real-time 3D virtual reality model of the tumor and the puncture needle in the breast. Under guidance by the navigation system, marking procedures were performed without any difficulties. Fiducial registration errors were 3.00 mm for patient no.1, and 4.07 mm for patient no.2. The real-time 3D virtual reality navigation system with open MRI is feasible for safe and accurate excision of non-palpable MRI-detected breast tumors. (author)

  10. Bio-robots automatic navigation with electrical reward stimulation.

    Science.gov (United States)

    Sun, Chao; Zhang, Xinlu; Zheng, Nenggan; Chen, Weidong; Zheng, Xiaoxiang

    2012-01-01

    Bio-robots that controlled by outer stimulation through brain computer interface (BCI) suffer from the dependence on realtime guidance of human operators. Current automatic navigation methods for bio-robots focus on the controlling rules to force animals to obey man-made commands, with animals' intelligence ignored. This paper proposes a new method to realize the automatic navigation for bio-robots with electrical micro-stimulation as real-time rewards. Due to the reward-seeking instinct and trial-and-error capability, bio-robot can be steered to keep walking along the right route with rewards and correct its direction spontaneously when rewards are deprived. In navigation experiments, rat-robots learn the controlling methods in short time. The results show that our method simplifies the controlling logic and realizes the automatic navigation for rat-robots successfully. Our work might have significant implication for the further development of bio-robots with hybrid intelligence.

  11. A Wearable Goggle Navigation System for Dual-Mode Optical and Ultrasound Localization of Suspicious Lesions: Validation Studies Using Tissue-Simulating Phantoms and an Ex Vivo Human Breast Tissue Model.

    Directory of Open Access Journals (Sweden)

    Zeshu Zhang

    Full Text Available Surgical resection remains the primary curative treatment for many early-stage cancers, including breast cancer. The development of intraoperative guidance systems for identifying all sites of disease and improving the likelihood of complete surgical resection is an area of active ongoing research, as this can lead to a decrease in the need of subsequent additional surgical procedures. We develop a wearable goggle navigation system for dual-mode optical and ultrasound imaging of suspicious lesions. The system consists of a light source module, a monochromatic CCD camera, an ultrasound system, a Google Glass, and a host computer. It is tested in tissue-simulating phantoms and an ex vivo human breast tissue model. Our experiments demonstrate that the surgical navigation system provides useful guidance for localization and core needle biopsy of simulated tumor within the tissue-simulating phantom, as well as a core needle biopsy and subsequent excision of Indocyanine Green (ICG-fluorescing sentinel lymph nodes. Our experiments support the contention that this wearable goggle navigation system can be potentially very useful and fully integrated by the surgeon for optimizing many aspects of oncologic surgery. Further engineering optimization and additional in vivo clinical validation work is necessary before such a surgical navigation system can be fully realized in the everyday clinical setting.

  12. Nuclear Regulatory Commission staff approaches to improving the integration of regulatory guidance documents and prelicensing reviews

    International Nuclear Information System (INIS)

    Johnson, R.L.

    1994-01-01

    The Nuclear Regulatory Commission staff is conducting numerous activities to improve the integration of its regulatory guidance documents (i.e., License Application Review Plan (LARP) and open-quotes Format and Content for the License Application for the High-Level Waste repositoryclose quotes (FCRG)) and pre-license application (LA) reviews. Those activities related to the regulatory guidance documents consist of: (1) developing an hierarchy of example evaluation findings for LARP; (2) identifying LARP review plan interfaces; (3) conducting an integration review of LARP review strategies; (4) correlating LARP to the ongoing technical program; and (5) revising the FCRG. Some of the more important strategies the staff is using to improve the integration of pre-LA reviews with the LA review include: (1) use of the draft LARP to guide the staff's pre-LA reviews; (2) focus detailed pre-LA reviews on key technical uncertainties; (3) identify and track concerns with DOE's program; and (4) use results of pre-LA reviews in LA reviews. The purpose of this paper is to describe these ongoing activities and strategies and discuss some of the new work that is planned to be included in LARP Revision 1 and the final FCRG, which are scheduled to be issued in late 1994. These activities reflect both the importance the staff has placed on integration and the staff's approach to improving integration in these areas. The staff anticipates that the results of these activities, when incorporated in the FCRG, LARP, and pre-LA reviews, will improve its guidance for DOE's ongoing site characterization program and LA annotated outline development

  13. Configuring the Orion Guidance, Navigation, and Control Flight Software for Automated Sequencing

    Science.gov (United States)

    Odegard, Ryan G.; Siliwinski, Tomasz K.; King, Ellis T.; Hart, Jeremy J.

    2010-01-01

    The Orion Crew Exploration Vehicle is being designed with greater automation capabilities than any other crewed spacecraft in NASA s history. The Guidance, Navigation, and Control (GN&C) flight software architecture is designed to provide a flexible and evolvable framework that accommodates increasing levels of automation over time. Within the GN&C flight software, a data-driven approach is used to configure software. This approach allows data reconfiguration and updates to automated sequences without requiring recompilation of the software. Because of the great dependency of the automation and the flight software on the configuration data, the data management is a vital component of the processes for software certification, mission design, and flight operations. To enable the automated sequencing and data configuration of the GN&C subsystem on Orion, a desktop database configuration tool has been developed. The database tool allows the specification of the GN&C activity sequences, the automated transitions in the software, and the corresponding parameter reconfigurations. These aspects of the GN&C automation on Orion are all coordinated via data management, and the database tool provides the ability to test the automation capabilities during the development of the GN&C software. In addition to providing the infrastructure to manage the GN&C automation, the database tool has been designed with capabilities to import and export artifacts for simulation analysis and documentation purposes. Furthermore, the database configuration tool, currently used to manage simulation data, is envisioned to evolve into a mission planning tool for generating and testing GN&C software sequences and configurations. A key enabler of the GN&C automation design, the database tool allows both the creation and maintenance of the data artifacts, as well as serving the critical role of helping to manage, visualize, and understand the data-driven parameters both during software development

  14. Blindness enhances auditory obstacle circumvention: Assessing echolocation, sensory substitution, and visual-based navigation.

    Science.gov (United States)

    Kolarik, Andrew J; Scarfe, Amy C; Moore, Brian C J; Pardhan, Shahina

    2017-01-01

    Performance for an obstacle circumvention task was assessed under conditions of visual, auditory only (using echolocation) and tactile (using a sensory substitution device, SSD) guidance. A Vicon motion capture system was used to measure human movement kinematics objectively. Ten normally sighted participants, 8 blind non-echolocators, and 1 blind expert echolocator navigated around a 0.6 x 2 m obstacle that was varied in position across trials, at the midline of the participant or 25 cm to the right or left. Although visual guidance was the most effective, participants successfully circumvented the obstacle in the majority of trials under auditory or SSD guidance. Using audition, blind non-echolocators navigated more effectively than blindfolded sighted individuals with fewer collisions, lower movement times, fewer velocity corrections and greater obstacle detection ranges. The blind expert echolocator displayed performance similar to or better than that for the other groups using audition, but was comparable to that for the other groups using the SSD. The generally better performance of blind than of sighted participants is consistent with the perceptual enhancement hypothesis that individuals with severe visual deficits develop improved auditory abilities to compensate for visual loss, here shown by faster, more fluid, and more accurate navigation around obstacles using sound.

  15. Blindness enhances auditory obstacle circumvention: Assessing echolocation, sensory substitution, and visual-based navigation.

    Directory of Open Access Journals (Sweden)

    Andrew J Kolarik

    Full Text Available Performance for an obstacle circumvention task was assessed under conditions of visual, auditory only (using echolocation and tactile (using a sensory substitution device, SSD guidance. A Vicon motion capture system was used to measure human movement kinematics objectively. Ten normally sighted participants, 8 blind non-echolocators, and 1 blind expert echolocator navigated around a 0.6 x 2 m obstacle that was varied in position across trials, at the midline of the participant or 25 cm to the right or left. Although visual guidance was the most effective, participants successfully circumvented the obstacle in the majority of trials under auditory or SSD guidance. Using audition, blind non-echolocators navigated more effectively than blindfolded sighted individuals with fewer collisions, lower movement times, fewer velocity corrections and greater obstacle detection ranges. The blind expert echolocator displayed performance similar to or better than that for the other groups using audition, but was comparable to that for the other groups using the SSD. The generally better performance of blind than of sighted participants is consistent with the perceptual enhancement hypothesis that individuals with severe visual deficits develop improved auditory abilities to compensate for visual loss, here shown by faster, more fluid, and more accurate navigation around obstacles using sound.

  16. A goggle navigation system for cancer resection surgery

    Science.gov (United States)

    Xu, Junbin; Shao, Pengfei; Yue, Ting; Zhang, Shiwu; Ding, Houzhu; Wang, Jinkun; Xu, Ronald

    2014-02-01

    We describe a portable fluorescence goggle navigation system for cancer margin assessment during oncologic surgeries. The system consists of a computer, a head mount display (HMD) device, a near infrared (NIR) CCD camera, a miniature CMOS camera, and a 780 nm laser diode excitation light source. The fluorescence and the background images of the surgical scene are acquired by the CCD camera and the CMOS camera respectively, co-registered, and displayed on the HMD device in real-time. The spatial resolution and the co-registration deviation of the goggle navigation system are evaluated quantitatively. The technical feasibility of the proposed goggle system is tested in an ex vivo tumor model. Our experiments demonstrate the feasibility of using a goggle navigation system for intraoperative margin detection and surgical guidance.

  17. INS/GPS/LiDAR Integrated Navigation System for Urban and Indoor Environments Using Hybrid Scan Matching Algorithm.

    Science.gov (United States)

    Gao, Yanbin; Liu, Shifei; Atia, Mohamed M; Noureldin, Aboelmagd

    2015-09-15

    This paper takes advantage of the complementary characteristics of Global Positioning System (GPS) and Light Detection and Ranging (LiDAR) to provide periodic corrections to Inertial Navigation System (INS) alternatively in different environmental conditions. In open sky, where GPS signals are available and LiDAR measurements are sparse, GPS is integrated with INS. Meanwhile, in confined outdoor environments and indoors, where GPS is unreliable or unavailable and LiDAR measurements are rich, LiDAR replaces GPS to integrate with INS. This paper also proposes an innovative hybrid scan matching algorithm that combines the feature-based scan matching method and Iterative Closest Point (ICP) based scan matching method. The algorithm can work and transit between two modes depending on the number of matched line features over two scans, thus achieving efficiency and robustness concurrently. Two integration schemes of INS and LiDAR with hybrid scan matching algorithm are implemented and compared. Real experiments are performed on an Unmanned Ground Vehicle (UGV) for both outdoor and indoor environments. Experimental results show that the multi-sensor integrated system can remain sub-meter navigation accuracy during the whole trajectory.

  18. Guidance, Navigation and Control (GN and C) Design Overview and Flight Test Results from NASA's Max Launch Abort System (MLAS)

    Science.gov (United States)

    Dennehy, Cornelius J.; Lanzi, Raymond J.; Ward, Philip R.

    2010-01-01

    The National Aeronautics and Space Administration Engineering and Safety Center designed, developed and flew the alternative Max Launch Abort System (MLAS) as risk mitigation for the baseline Orion spacecraft launch abort system already in development. The NESC was tasked with both formulating a conceptual objective system design of this alternative MLAS as well as demonstrating this concept with a simulated pad abort flight test. Less than 2 years after Project start the MLAS simulated pad abort flight test was successfully conducted from Wallops Island on July 8, 2009. The entire flight test duration was 88 seconds during which time multiple staging events were performed and nine separate critically timed parachute deployments occurred as scheduled. This paper provides an overview of the guidance navigation and control technical approaches employed on this rapid prototyping activity; describes the methodology used to design the MLAS flight test vehicle; and lessons that were learned during this rapid prototyping project are also summarized.

  19. Using Inertial Sensors in Smartphones for Curriculum Experiments of Inertial Navigation Technology

    OpenAIRE

    Niu, Xiaoji; Wang, Qingjiang; Li, You; Li, Qingli; Liu, Jingnan

    2015-01-01

    Inertial technology has been used in a wide range of applications such as guidance, navigation, and motion tracking. However, there are few undergraduate courses that focus on the inertial technology. Traditional inertial navigation systems (INS) and relevant testing facilities are expensive and complicated in operation, which makes it inconvenient and risky to perform teaching experiments with such systems. To solve this issue, this paper proposes the idea of using smartphones, which are ubi...

  20. Spacecraft intercept guidance using zero effort miss steering

    Science.gov (United States)

    Newman, Brett

    The suitability of proportional navigation, or an equivalent zero effort miss formulation, for spacecraft intercepts during midcourse guidance, followed by a ballistic coast to the endgame, is addressed. The problem is formulated in terms of relative motion in a general 3D framework. The proposed guidance law for the commanded thrust vector orientation consists of the sum of two terms: (1) along the line of sight unit direction and (2) along the zero effort miss component perpendicular to the line of sight and proportional to the miss itself and a guidance gain. If the guidance law is to be suitable for longer range targeting applications with significant ballistic coasting after burnout, determination of the zero effort miss must account for the different gravitational accelerations experienced by each vehicle. The proposed miss determination techniques employ approximations for the true differential gravity effect. Theoretical results are applied to a numerical engagement scenario and the resulting performance is evaluated in terms of the miss distances determined from nonlinear simulation.

  1. Model-base visual navigation of a mobile robot

    International Nuclear Information System (INIS)

    Roening, J.

    1992-08-01

    The thesis considers the problems of visual guidance of a mobile robot. A visual navigation system is formalized consisting of four basic components: world modelling, navigation sensing, navigation and action. According to this formalization an experimental system is designed and realized enabling real-world navigation experiments. A priori knowledge of the world is used for global path finding, aiding scene analysis and providing feedback information to the close the control loop between planned and actual movements. Two world models were developed. The first approach was a map-based model especially designed for low-level description of indoor environments. The other was a higher level and more symbolic representation of the surroundings utilizing the spatial graph concept. Two passive vision approaches were developed to extract navigation information. With passive three- camera stereovision a sparse depth map of the scene was produced. Another approach employed a fish-eye lens to map the entire scene of the surroundings without camera scanning. The local path planning of the system is supported by three-dimensional scene interpreter providing a partial understanding of scene contents. The interpreter consists of data-driven low-level stages and a model-driven high-level stage. Experiments were carried out in a simulator and test vehicle constructed in the laboratory. The test vehicle successfully navigated indoors

  2. GPS surveying method applied to terminal area navigation flight experiments

    Energy Technology Data Exchange (ETDEWEB)

    Murata, M; Shingu, H; Satsushima, K; Tsuji, T; Ishikawa, K; Miyazawa, Y; Uchida, T [National Aerospace Laboratory, Tokyo (Japan)

    1993-03-01

    With an objective of evaluating accuracy of new landing and navigation systems such as microwave landing guidance system and global positioning satellite (GPS) system, flight experiments are being carried out using experimental aircraft. This aircraft mounts a GPS and evaluates its accuracy by comparing the standard orbits spotted by a Kalman filter from the laser tracing data on the aircraft with the navigation results. The GPS outputs position and speed information from an earth-centered-earth-fixed system called the World Geodetic System, 1984 (WGS84). However, in order to compare the navigation results with output from a reference orbit sensor or other navigation sensor, it is necessary to structure a high-precision reference coordinates system based on the WGS84. A method that applies the GPS phase interference measurement for this problem was proposed, and used actually in analyzing a flight experiment data. As referred to a case of the method having been applied to evaluating an independent navigation accuracy, the method was verified sufficiently effective and reliable not only in navigation method analysis, but also in the aspect of navigational operations. 12 refs., 10 figs., 5 tabs.

  3. Navigating the National Qualifications Framework (NQF): The Role of Career Guidance

    Science.gov (United States)

    Walters, S.; Watts, A. G.; Flederman, P.

    2009-01-01

    The South African Qualifications Authority (SAQA) recently commissioned a review of the career development field in South Africa. The review was designed to clarify what SAQA's role might be in assisting learners throughout life to navigate their ways through the complex array of education, training and work opportunities (including, but not…

  4. GNSS-based receiver autonomous integrity monitoring for aircraft navigation

    NARCIS (Netherlands)

    Imparato, D.

    2016-01-01

    Nowadays, GNSS-based navigation is moving more and more to critical applications. Global Navigation Satellite Systems (GNSS), which in the past used to be represented by the American GPS and the Russian GLONASS are now growing in number and performance. The European systemGalileo and the Chinese

  5. Integrating Communication and Navigation: Next Generation Broadcast Service (NGBS)

    Science.gov (United States)

    Donaldson, Jennifer

    2017-01-01

    NASA Goddard has been investing in technology demonstrations of a beacon service, now called Next Generation Broadcast Services (NGBS). NGBS is a global, space-based, communications and navigation service for users of Global Navigation Satellite Systems (GNSS) and the Tracking and Data Relay Satellite System (TDRSS). NGBS will provide an S-band beacon messaging source and radio navigation available to users at orbital altitudes 1400 km and below, increasing the autonomy and resiliency of onboard communication and navigation. NGBS will deliver both one-way radiometric (Doppler and pseudorange) and fast forward data transport services to users. Portions of the overall forward data volume will be allocated for fixed message types while the remaining data volume will be left for user forward command data. The NGBS signal will reside within the 2106.43 MHz spectrum currently allocated for the Space Networks multiple access forward (MAF) service and a live service demonstration is currently being planned via the 2nd and 3rd generation TDRS satellites.

  6. Inertial navigation without accelerometers

    Science.gov (United States)

    Boehm, M.

    The Kennedy-Thorndike (1932) experiment points to the feasibility of fiber-optic inertial velocimeters, to which state-of-the-art technology could furnish substantial sensitivity and accuracy improvements. Velocimeters of this type would obviate the use of both gyros and accelerometers, and allow inertial navigation to be conducted together with vehicle attitude control, through the derivation of rotation rates from the ratios of the three possible velocimeter pairs. An inertial navigator and reference system based on this approach would probably have both fewer components and simpler algorithms, due to the obviation of the first level of integration in classic inertial navigators.

  7. The integrated performance evaluation program quality assurance guidance in support of EM environmental sampling and analysis activities

    International Nuclear Information System (INIS)

    1994-05-01

    EM's (DOE's Environmental Restoration and Waste Management) Integrated Performance Evaluation Program (IPEP) has the purpose of integrating information from existing PE programs with expanded QA activities to develop information about the quality of radiological, mixed waste, and hazardous environmental sample analyses provided by all laboratories supporting EM programs. The guidance addresses the goals of identifying specific PE sample programs and contacts, identifying specific requirements for participation in DOE's internal and external (regulatory) programs, identifying key issues relating to application and interpretation of PE materials for EM headquarters and field office managers, and providing technical guidance covering PE materials for site-specific activities. (PE) Performance Evaluation materials or samples are necessary for the quality assurance/control programs covering environmental data collection

  8. Surgical Navigation Technology Based on Augmented Reality and Integrated 3D Intraoperative Imaging

    Science.gov (United States)

    Elmi-Terander, Adrian; Skulason, Halldor; Söderman, Michael; Racadio, John; Homan, Robert; Babic, Drazenko; van der Vaart, Nijs; Nachabe, Rami

    2016-01-01

    Study Design. A cadaveric laboratory study. Objective. The aim of this study was to assess the feasibility and accuracy of thoracic pedicle screw placement using augmented reality surgical navigation (ARSN). Summary of Background Data. Recent advances in spinal navigation have shown improved accuracy in lumbosacral pedicle screw placement but limited benefits in the thoracic spine. 3D intraoperative imaging and instrument navigation may allow improved accuracy in pedicle screw placement, without the use of x-ray fluoroscopy, and thus opens the route to image-guided minimally invasive therapy in the thoracic spine. Methods. ARSN encompasses a surgical table, a motorized flat detector C-arm with intraoperative 2D/3D capabilities, integrated optical cameras for augmented reality navigation, and noninvasive patient motion tracking. Two neurosurgeons placed 94 pedicle screws in the thoracic spine of four cadavers using ARSN on one side of the spine (47 screws) and free-hand technique on the contralateral side. X-ray fluoroscopy was not used for either technique. Four independent reviewers assessed the postoperative scans, using the Gertzbein grading. Morphometric measurements of the pedicles axial and sagittal widths and angles, as well as the vertebrae axial and sagittal rotations were performed to identify risk factors for breaches. Results. ARSN was feasible and superior to free-hand technique with respect to overall accuracy (85% vs. 64%, P dimensions, except for vertebral body axial rotation, were risk factors for larger breaches when performed with the free-hand method. Conclusion. ARSN without fluoroscopy was feasible and demonstrated higher accuracy than free-hand technique for thoracic pedicle screw placement. Level of Evidence: N/A PMID:27513166

  9. A Short Tutorial on Inertial Navigation System and Global Positioning System Integration

    Science.gov (United States)

    Smalling, Kyle M.; Eure, Kenneth W.

    2015-01-01

    The purpose of this document is to describe a simple method of integrating Inertial Navigation System (INS) information with Global Positioning System (GPS) information for an improved estimate of vehicle attitude and position. A simple two dimensional (2D) case is considered. The attitude estimates are derived from sensor data and used in the estimation of vehicle position and velocity through dead reckoning within the INS. The INS estimates are updated with GPS estimates using a Kalman filter. This tutorial is intended for the novice user with a focus on bringing the reader from raw sensor measurements to an integrated position and attitude estimate. An application is given using a remotely controlled ground vehicle operating in assumed 2D environment. The theory is developed first followed by an illustrative example.

  10. The Design of a Modified PSO Guidance Law Using Predictor and LOS Rate Evaluation

    Directory of Open Access Journals (Sweden)

    Lee Yung-Lung

    2016-01-01

    Full Text Available This paper proposes a modified particle swarm optimization guidance (MPSOG for the pursuit-evasion optimization problem. If the line-of-sight (LOS rate equals zero, the curvature of the missile’s trajectory would be smaller and the probability of intercept greater. Thus, we propose using a MPSOG to improve the guidance performance. The MPSOG uses a Kalman filter to predict a target’s dynamic. The lateral acceleration commands of the y- and z-axis are optimized by the particle swarm optimization (PSO algorithm, respectively. Numerical simulation results show that the MPSOG have better guidance performance than proportional navigation guidance and particle swarm optimization guidance in miss distance, time-to-go, and final lateral acceleration commands.

  11. Integrated design for space transportation system

    CERN Document Server

    Suresh, B N

    2015-01-01

    The book addresses the overall integrated design aspects of a space transportation system involving several disciplines like propulsion, vehicle structures, aerodynamics, flight mechanics, navigation, guidance and control systems, stage auxiliary systems, thermal systems etc. and discusses the system approach for design, trade off analysis, system life cycle considerations, important aspects in mission management, the risk assessment, etc. There are several books authored to describe the design aspects of various areas, viz., propulsion, aerodynamics, structures, control, etc., but there is no book which presents space transportation system (STS) design in an integrated manner. This book attempts to fill this gap by addressing systems approach for STS design, highlighting the integrated design aspects, interactions between various subsystems and interdependencies. The main focus is towards the complex integrated design to arrive at an optimum, robust and cost effective space transportation system. The orbit...

  12. Quantifying navigational information: The catchment volumes of panoramic snapshots in outdoor scenes.

    Directory of Open Access Journals (Sweden)

    Trevor Murray

    Full Text Available Panoramic views of natural environments provide visually navigating animals with two kinds of information: they define locations because image differences increase smoothly with distance from a reference location and they provide compass information, because image differences increase smoothly with rotation away from a reference orientation. The range over which a given reference image can provide navigational guidance (its 'catchment area' has to date been quantified from the perspective of walking animals by determining how image differences develop across the ground plane of natural habitats. However, to understand the information available to flying animals there is a need to characterize the 'catchment volumes' within which panoramic snapshots can provide navigational guidance. We used recently developed camera-based methods for constructing 3D models of natural environments and rendered panoramic views at defined locations within these models with the aim of mapping navigational information in three dimensions. We find that in relatively open woodland habitats, catchment volumes are surprisingly large extending for metres depending on the sensitivity of the viewer to image differences. The size and the shape of catchment volumes depend on the distance of visual features in the environment. Catchment volumes are smaller for reference images close to the ground and become larger for reference images at some distance from the ground and in more open environments. Interestingly, catchment volumes become smaller when only above horizon views are used and also when views include a 1 km distant panorama. We discuss the current limitations of mapping navigational information in natural environments and the relevance of our findings for our understanding of visual navigation in animals and autonomous robots.

  13. Quantifying navigational information: The catchment volumes of panoramic snapshots in outdoor scenes.

    Science.gov (United States)

    Murray, Trevor; Zeil, Jochen

    2017-01-01

    Panoramic views of natural environments provide visually navigating animals with two kinds of information: they define locations because image differences increase smoothly with distance from a reference location and they provide compass information, because image differences increase smoothly with rotation away from a reference orientation. The range over which a given reference image can provide navigational guidance (its 'catchment area') has to date been quantified from the perspective of walking animals by determining how image differences develop across the ground plane of natural habitats. However, to understand the information available to flying animals there is a need to characterize the 'catchment volumes' within which panoramic snapshots can provide navigational guidance. We used recently developed camera-based methods for constructing 3D models of natural environments and rendered panoramic views at defined locations within these models with the aim of mapping navigational information in three dimensions. We find that in relatively open woodland habitats, catchment volumes are surprisingly large extending for metres depending on the sensitivity of the viewer to image differences. The size and the shape of catchment volumes depend on the distance of visual features in the environment. Catchment volumes are smaller for reference images close to the ground and become larger for reference images at some distance from the ground and in more open environments. Interestingly, catchment volumes become smaller when only above horizon views are used and also when views include a 1 km distant panorama. We discuss the current limitations of mapping navigational information in natural environments and the relevance of our findings for our understanding of visual navigation in animals and autonomous robots.

  14. A Terminal Guidance Law Based on Motion Camouflage Strategy of Air-to-Ground Missiles

    Directory of Open Access Journals (Sweden)

    Chang-sheng Gao

    2016-01-01

    Full Text Available A guidance law for attacking ground target based on motion camouflage strategy is proposed in this paper. According to the relative position between missile and target, the dual second-order dynamics model is derived. The missile guidance condition is given by analyzing the characteristic of motion camouflage strategy. Then, the terminal guidance law is derived by using the relative motion of missile and target and the guidance condition. In the process of derivation, the three-dimensional guidance law could be designed in a two-dimensional plane and the difficulty of guidance law design is reduced. A two-dimensional guidance law for three-dimensional space is derived by bringing the estimation for target maneuver. Finally, simulation for the proposed guidance law is taken and compared with pure proportional navigation. The simulation results demonstrate that the proposed guidance law can be applied to air-to-ground missiles.

  15. Design, Implementation and Evaluation of an Indoor Navigation System for Visually Impaired People.

    Science.gov (United States)

    Martinez-Sala, Alejandro Santos; Losilla, Fernando; Sánchez-Aarnoutse, Juan Carlos; García-Haro, Joan

    2015-12-21

    Indoor navigation is a challenging task for visually impaired people. Although there are guidance systems available for such purposes, they have some drawbacks that hamper their direct application in real-life situations. These systems are either too complex, inaccurate, or require very special conditions (i.e., rare in everyday life) to operate. In this regard, Ultra-Wideband (UWB) technology has been shown to be effective for indoor positioning, providing a high level of accuracy and low installation complexity. This paper presents SUGAR, an indoor navigation system for visually impaired people which uses UWB for positioning, a spatial database of the environment for pathfinding through the application of the A* algorithm, and a guidance module. The interaction with the user takes place using acoustic signals and voice commands played through headphones. The suitability of the system for indoor navigation has been verified by means of a functional and usable prototype through a field test with a blind person. In addition, other tests have been conducted in order to show the accuracy of different relevant parts of the system.

  16. Design, Implementation and Evaluation of an Indoor Navigation System for Visually Impaired People

    Directory of Open Access Journals (Sweden)

    Alejandro Santos Martinez-Sala

    2015-12-01

    Full Text Available Indoor navigation is a challenging task for visually impaired people. Although there are guidance systems available for such purposes, they have some drawbacks that hamper their direct application in real-life situations. These systems are either too complex, inaccurate, or require very special conditions (i.e., rare in everyday life to operate. In this regard, Ultra-Wideband (UWB technology has been shown to be effective for indoor positioning, providing a high level of accuracy and low installation complexity. This paper presents SUGAR, an indoor navigation system for visually impaired people which uses UWB for positioning, a spatial database of the environment for pathfinding through the application of the A* algorithm, and a guidance module. The interaction with the user takes place using acoustic signals and voice commands played through headphones. The suitability of the system for indoor navigation has been verified by means of a functional and usable prototype through a field test with a blind person. In addition, other tests have been conducted in order to show the accuracy of different relevant parts of the system.

  17. Robot-assisted endoscope guidance versus manual endoscope guidance in functional endonasal sinus surgery (FESS).

    Science.gov (United States)

    Eichhorn, Klaus Wolfgang; Westphal, Ralf; Rilk, Markus; Last, Carsten; Bootz, Friedrich; Wahl, Friedrich; Jakob, Mark; Send, Thorsten

    2017-10-01

    Having one hand occupied with the endoscope is the major disadvantage for the surgeon when it comes to functional endoscopic sinus surgery (FESS). Only the other hand is free to use the surgical instruments. Tiredness or frequent instrument changes can thus lead to shaky endoscopic images. We collected the pose data (position and orientation) of the rigid 0° endoscope and all the instruments used in 16 FESS procedures with manual endoscope guidance as well as robot-assisted endoscope guidance. In combination with the DICOM CT data, we tracked the endoscope poses and workspaces using self-developed tracking markers. All surgeries were performed once with the robot and once with the surgeon holding the endoscope. Looking at the durations required, we observed a decrease in the operating time because one surgeon doing all the procedures and so a learning curve occurred what we expected. The visual inspection of the specimens showed no damages to any of the structures outside the paranasal sinuses. Robot-assisted endoscope guidance in sinus surgery is possible. Further CT data, however, are desirable for the surgical analysis of a tracker-based navigation within the anatomic borders. Our marker-based tracking of the endoscope as well as the instruments makes an automated endoscope guidance feasible. On the subjective side, we see that RASS brings a relief for the surgeon.

  18. Recent Experiences of the NASA Engineering and Safety Center (NESC) Guidance Navigation and Control (GN and C) Technical Discipline Team (TDT)

    Science.gov (United States)

    Dennehy, Cornelius J.

    2011-01-01

    The NASA Engineering and Safety Center (NESC) is an independently funded NASA Program whose dedicated team of technical experts provides objective engineering and safety assessments of critical, high risk projects. NESC's strength is rooted in the diverse perspectives and broad knowledge base that add value to its products, affording customers a responsive, alternate path for assessing and preventing technical problems while protecting vital human and national resources. The Guidance Navigation and Control (GN&C) Technical Discipline Team (TDT) is one of fifteen such discipline-focused teams within the NESC organization. The TDT membership is composed of GN&C specialists from across NASA and its partner organizations in other government agencies, industry, national laboratories, and universities. This paper will briefly define the vision, mission, and purpose of the NESC organization. The role of the GN&C TDT will then be described in detail along with an overview of how this team operates and engages in its objective engineering and safety assessments of critical NASA.

  19. Techniques for Interventional MRI Guidance in Closed-Bore Systems.

    Science.gov (United States)

    Busse, Harald; Kahn, Thomas; Moche, Michael

    2018-02-01

    Efficient image guidance is the basis for minimally invasive interventions. In comparison with X-ray, computed tomography (CT), or ultrasound imaging, magnetic resonance imaging (MRI) provides the best soft tissue contrast without ionizing radiation and is therefore predestined for procedural control. But MRI is also characterized by spatial constraints, electromagnetic interactions, long imaging times, and resulting workflow issues. Although many technical requirements have been met over the years-most notably magnetic resonance (MR) compatibility of tools, interventional pulse sequences, and powerful processing hardware and software-there is still a large variety of stand-alone devices and systems for specific procedures only.Stereotactic guidance with the table outside the magnet is common and relies on proper registration of the guiding grids or manipulators to the MR images. Instrument tracking, often by optical sensing, can be added to provide the physicians with proper eye-hand coordination during their navigated approach. Only in very short wide-bore systems, needles can be advanced at the extended arm under near real-time imaging. In standard magnets, control and workflow may be improved by remote operation using robotic or manual driving elements.This work highlights a number of devices and techniques for different interventional settings with a focus on percutaneous, interstitial procedures in different organ regions. The goal is to identify technical and procedural elements that might be relevant for interventional guidance in a broader context, independent of the clinical application given here. Key challenges remain the seamless integration into the interventional workflow, safe clinical translation, and proper cost effectiveness.

  20. Hybrid Guidance Control for a Hypervelocity Small Size Asteroid Interceptor Vehicle

    Science.gov (United States)

    Zebenay, Melak M.; Lyzhoft, Joshua R.; Barbee, Brent W.

    2017-01-01

    Near-Earth Objects (NEOs) are comets and/or asteroids that have orbits in proximity with Earth's own orbit. NEOs have collided with the Earth in the past, which can be seen at such places as Chicxulub crater, Barringer crater, and Manson crater, and will continue in the future with potentially significant and devastating results. Fortunately such NEO collisions with Earth are infrequent, but can happen at any time. Therefore it is necessary to develop and validate techniques as well as technologies necessary to prevent them. One approach to mitigate future NEO impacts is the concept of high-speed interceptor. This concept is to alter the NEO's trajectory via momentum exchange by using kinetic impactors as well as nuclear penetration devices. The interceptor has to hit a target NEO at relative velocity which imparts a sufficient change in NEO velocity. NASA's Deep Impact mission has demonstrated this scenario by intercepting Comet Temple 1, 5 km in diameter, with an impact relative speed of approximately 10 km/s. This paper focuses on the development of hybrid guidance navigation and control (GNC) algorithms for precision hypervelocity intercept of small sized NEOs. The spacecraft's hypervelocity and the NEO's small size are critical challenges for a successful mission as the NEO will not fill the field of view until a few seconds before intercept. The investigation needs to consider the error sources modeled in the navigation simulation such as spacecraft initial state uncertainties in position and velocity. Furthermore, the paper presents three selected spacecraft guidance algorithms for asteroid intercept and rendezvous missions. The selected algorithms are classical Proportional Navigation (PN) based guidance that use a first order difference to compute the derivatives, Three Plane Proportional Navigation (TPPN), and the Kinematic Impulse (KI). A manipulated Bennu orbit that has been changed to impact Earth will be used as a demonstrative example to compare the

  1. Three-dimensional Cross-Platform Planning for Complex Spinal Procedures: A New Method Adaptive to Different Navigation Systems.

    Science.gov (United States)

    Kosterhon, Michael; Gutenberg, Angelika; Kantelhardt, Sven R; Conrad, Jens; Nimer Amr, Amr; Gawehn, Joachim; Giese, Alf

    2017-08-01

    A feasibility study. To develop a method based on the DICOM standard which transfers complex 3-dimensional (3D) trajectories and objects from external planning software to any navigation system for planning and intraoperative guidance of complex spinal procedures. There have been many reports about navigation systems with embedded planning solutions but only few on how to transfer planning data generated in external software. Patients computerized tomography and/or magnetic resonance volume data sets of the affected spinal segments were imported to Amira software, reconstructed to 3D images and fused with magnetic resonance data for soft-tissue visualization, resulting in a virtual patient model. Objects needed for surgical plans or surgical procedures such as trajectories, implants or surgical instruments were either digitally constructed or computerized tomography scanned and virtually positioned within the 3D model as required. As crucial step of this method these objects were fused with the patient's original diagnostic image data, resulting in a single DICOM sequence, containing all preplanned information necessary for the operation. By this step it was possible to import complex surgical plans into any navigation system. We applied this method not only to intraoperatively adjustable implants and objects under experimental settings, but also planned and successfully performed surgical procedures, such as the percutaneous lateral approach to the lumbar spine following preplanned trajectories and a thoracic tumor resection including intervertebral body replacement using an optical navigation system. To demonstrate the versatility and compatibility of the method with an entirely different navigation system, virtually preplanned lumbar transpedicular screw placement was performed with a robotic guidance system. The presented method not only allows virtual planning of complex surgical procedures, but to export objects and surgical plans to any navigation or

  2. Evaluation of a mobile augmented reality application for image guidance of neurosurgical interventions.

    Science.gov (United States)

    Kramers, Matthew; Armstrong, Ryan; Bakhshmand, Saeed M; Fenster, Aaron; de Ribaupierre, Sandrine; Eagleson, Roy

    2014-01-01

    Image guidance can provide surgeons with valuable contextual information during a medical intervention. Often, image guidance systems require considerable infrastructure, setup-time, and operator experience to be utilized. Certain procedures performed at bedside are susceptible to navigational errors that can lead to complications. We present an application for mobile devices that can provide image guidance using augmented reality to assist in performing neurosurgical tasks. A methodology is outlined that evaluates this mode of visualization from the standpoint of perceptual localization, depth estimation, and pointing performance, in scenarios derived from a neurosurgical targeting task. By measuring user variability and speed we can report objective metrics of performance for our augmented reality guidance system.

  3. Engineering and Design: Reliability Analysis of Navigation Lock and Dam Mechanical and Electrical Equipment

    National Research Council Canada - National Science Library

    Beranek, Dwight

    2001-01-01

    This engineer technical letter (ETL) provides guidance for assessing the reliability of mechanical and electrical systems of navigation locks and dams and for establishing an engineering basis for major rehabilitation investment decisions...

  4. Midcourse Guidance Law Based on High Target Acquisition Probability Considering Angular Constraint and Line-of-Sight Angle Rate Control

    Directory of Open Access Journals (Sweden)

    Xiao Liu

    2016-01-01

    Full Text Available Random disturbance factors would lead to the variation of target acquisition point during the long distance flight. To acquire a high target acquisition probability and improve the impact precision, missiles should be guided to an appropriate target acquisition position with certain attitude angles and line-of-sight (LOS angle rate. This paper has presented a new midcourse guidance law considering the influences of random disturbances, detection distance restraint, and target acquisition probability with Monte Carlo simulation. Detailed analyses of the impact points on the ground and the random distribution of the target acquisition position in the 3D space are given to get the appropriate attitude angles and the end position for the midcourse guidance. Then, a new formulation biased proportional navigation (BPN guidance law with angular constraint and LOS angle rate control has been derived to ensure the tracking ability when attacking the maneuvering target. Numerical simulations demonstrates that, compared with the proportional navigation guidance (PNG law and the near-optimal spatial midcourse guidance (NSMG law, BPN guidance law demonstrates satisfactory performances and can meet both the midcourse terminal angular constraint and the LOS angle rate requirement.

  5. Autonomous Integrated Navigation for Indoor Robots Utilizing On-Line Iterated Extended Rauch-Tung-Striebel Smoothing

    Directory of Open Access Journals (Sweden)

    Yuan Xu

    2013-11-01

    Full Text Available In order to reduce the estimated errors of the inertial navigation system (INS/Wireless sensor network (WSN-integrated navigation for mobile robots indoors, this work proposes an on-line iterated extended Rauch-Tung-Striebel smoothing (IERTSS utilizing inertial measuring units (IMUs and an ultrasonic positioning system. In this mode, an iterated Extended Kalman filter (IEKF is used in forward data processing of the Extended Rauch-Tung-Striebel smoothing (ERTSS to improve the accuracy of the filtering output for the smoother. Furthermore, in order to achieve the on-line smoothing, IERTSS is embedded into the average filter. For verification, a real indoor test has been done to assess the performance of the proposed method. The results show that the proposed method is effective in reducing the errors compared with the conventional schemes.

  6. Constituent aspects of workplace guidance in secondary VET

    NARCIS (Netherlands)

    Swager, Robert; Klarus, Ruud; Van Merriënboer, Jeroen; Nieuwenhuis, Loek

    2018-01-01

    Purpose – This paper aims to present an integrated model of workplace guidance to enhance awareness of what constitutes good guidance, to improve workplace guidance practices in vocational education and training. Design/methodology/approach – To identify constituent aspects of workplace guidance,

  7. Adaptive Command Filtered Integrated Guidance and Control for Hypersonic Vehicle with Magnitude, Rate and Bandwidth Constraints

    Directory of Open Access Journals (Sweden)

    Wang Liang

    2018-01-01

    Full Text Available This paper proposes a novel integrated guidance and control (IGC method for hypersonic vehicle in terminal phase. Firstly, the system model is developed with a second order actuator dynamics. Then the back-stepping controller is designed hierarchically with command filters, where the first order command filters are implemented to construct the virtual control input with ideal states predicted by an adaptive estimator, and the nonlinear command filter is designed to produce magnitude, rate and bandwidth limited control surface deflection finally tracked by a terminal sliding mode controller with finite convergence time. Through a series of 6-DOF numerical simulations, it’s indicated that the proposed method successfully cancels out the large aerodynamics coefficient uncertainties and disturbances in hypersonic flight under limited control surface deflection. The contribution of this paper lies in the application and determination of nonlinear integrated design of guidance and control system for hypersonic vehicle.

  8. Navigational efficiency of nocturnal Myrmecia ants suffers at low light levels.

    Directory of Open Access Journals (Sweden)

    Ajay Narendra

    Full Text Available Insects face the challenge of navigating to specific goals in both bright sun-lit and dim-lit environments. Both diurnal and nocturnal insects use quite similar navigation strategies. This is despite the signal-to-noise ratio of the navigational cues being poor at low light conditions. To better understand the evolution of nocturnal life, we investigated the navigational efficiency of a nocturnal ant, Myrmecia pyriformis, at different light levels. Workers of M. pyriformis leave the nest individually in a narrow light-window in the evening twilight to forage on nest-specific Eucalyptus trees. The majority of foragers return to the nest in the morning twilight, while few attempt to return to the nest throughout the night. We found that as light levels dropped, ants paused for longer, walked more slowly, the success in finding the nest reduced and their paths became less straight. We found that in both bright and dark conditions ants relied predominantly on visual landmark information for navigation and that landmark guidance became less reliable at low light conditions. It is perhaps due to the poor navigational efficiency at low light levels that the majority of foragers restrict navigational tasks to the twilight periods, where sufficient navigational information is still available.

  9. Cochrane Qualitative and Implementation Methods Group guidance series-paper 5: methods for integrating qualitative and implementation evidence within intervention effectiveness reviews.

    Science.gov (United States)

    Harden, Angela; Thomas, James; Cargo, Margaret; Harris, Janet; Pantoja, Tomas; Flemming, Kate; Booth, Andrew; Garside, Ruth; Hannes, Karin; Noyes, Jane

    2018-05-01

    The Cochrane Qualitative and Implementation Methods Group develops and publishes guidance on the synthesis of qualitative and mixed-method evidence from process evaluations. Despite a proliferation of methods for the synthesis of qualitative research, less attention has focused on how to integrate these syntheses within intervention effectiveness reviews. In this article, we report updated guidance from the group on approaches, methods, and tools, which can be used to integrate the findings from quantitative studies evaluating intervention effectiveness with those from qualitative studies and process evaluations. We draw on conceptual analyses of mixed methods systematic review designs and the range of methods and tools that have been used in published reviews that have successfully integrated different types of evidence. We outline five key methods and tools as devices for integration which vary in terms of the levels at which integration takes place; the specialist skills and expertise required within the review team; and their appropriateness in the context of limited evidence. In situations where the requirement is the integration of qualitative and process evidence within intervention effectiveness reviews, we recommend the use of a sequential approach. Here, evidence from each tradition is synthesized separately using methods consistent with each tradition before integration takes place using a common framework. Reviews which integrate qualitative and process evaluation evidence alongside quantitative evidence on intervention effectiveness in a systematic way are rare. This guidance aims to support review teams to achieve integration and we encourage further development through reflection and formal testing. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. The Performance Analysis of a Real-Time Integrated INS/GPS Vehicle Navigation System with Abnormal GPS Measurement Elimination

    Directory of Open Access Journals (Sweden)

    Jhen-Kai Liao

    2013-08-01

    Full Text Available The integration of an Inertial Navigation System (INS and the Global Positioning System (GPS is common in mobile mapping and navigation applications to seamlessly determine the position, velocity, and orientation of the mobile platform. In most INS/GPS integrated architectures, the GPS is considered to be an accurate reference with which to correct for the systematic errors of the inertial sensors, which are composed of biases, scale factors and drift. However, the GPS receiver may produce abnormal pseudo-range errors mainly caused by ionospheric delay, tropospheric delay and the multipath effect. These errors degrade the overall position accuracy of an integrated system that uses conventional INS/GPS integration strategies such as loosely coupled (LC and tightly coupled (TC schemes. Conventional tightly coupled INS/GPS integration schemes apply the Klobuchar model and the Hopfield model to reduce pseudo-range delays caused by ionospheric delay and tropospheric delay, respectively, but do not address the multipath problem. However, the multipath effect (from reflected GPS signals affects the position error far more significantly in a consumer-grade GPS receiver than in an expensive, geodetic-grade GPS receiver. To avoid this problem, a new integrated INS/GPS architecture is proposed. The proposed method is described and applied in a real-time integrated system with two integration strategies, namely, loosely coupled and tightly coupled schemes, respectively. To verify the effectiveness of the proposed method, field tests with various scenarios are conducted and the results are compared with a reliable reference system.

  11. Teaching about the Earth Online: Faculty-Sourced Guidance from InTeGrate

    Science.gov (United States)

    McDaris, J. R.; Bralower, T. J.; Anbar, A. D.; Leinbach, A.

    2017-12-01

    Teaching online is growing in acceptance within the higher education community and its accessibility creates an opportunity to reach students from diverse backgrounds with geoscience content. There is a need to develop best practices for teaching about Earth online as new technologies, pedagogical approaches, and teaching materials that incorporate societal issues and data emerge. In response to this need, the InTeGrate: Teaching about Earth for a Sustainable Future project convened a workshop of interdisciplinary faculty who teach about the Earth online, in a variety of contexts, to develop consensus best-practices, collect online resources, and develop teaching materials to share with the rest of the community. Workshop participants generated five broad categories of guidance for faculty teaching online: develop communication and a sense of community among class participants, stimulate student engagement, develop activity frameworks that scale with class size, include information literacy in the curriculum explicitly, and employ effective management and assessment techniques. Many of the best practices highlighted by the group are not unique to teaching online, but teaching online rather than face-to-face affects how they are or can be implemented. The suite of webpages developed from this work showcase specific strategies in each area, underpinned by examples drawn from the experiences of the participants. This resource can provide a wealth of advice for faculty seeking help for teaching online. Faculty can also provide feedback on the strategies and add their own experiences to the collection. Participants also worked together in teams to develop new or revise existing teaching resources to make available via the InTeGrate website. In addition, they shared insights about online resources they use in their teaching and class management and developed plans for an online repository for next-generation, interactive educational materials and tools for creating them

  12. Biologically inspired autonomous agent navigation using an integrated polarization analyzing CMOS image sensor

    NARCIS (Netherlands)

    Sarkaer, M.; San Segundo Bello, D.; Van Hoof, C.; Theuwissen, A.

    2010-01-01

    The navigational strategies of insects using skylight polarization are interesting for applications in autonomous agent navigation because they rely on very little information for navigation. A polarization navigation sensor using the Stokes parameters to determine the orientation is presented. The

  13. Compact autonomous navigation system (CANS)

    Science.gov (United States)

    Hao, Y. C.; Ying, L.; Xiong, K.; Cheng, H. Y.; Qiao, G. D.

    2017-11-01

    Autonomous navigation of Satellite and constellation has series of benefits, such as to reduce operation cost and ground station workload, to avoid the event of crises of war and natural disaster, to increase spacecraft autonomy, and so on. Autonomous navigation satellite is independent of ground station support. Many systems are developed for autonomous navigation of satellite in the past 20 years. Along them American MANS (Microcosm Autonomous Navigation System) [1] of Microcosm Inc. and ERADS [2] [3] (Earth Reference Attitude Determination System) of Honeywell Inc. are well known. The systems anticipate a series of good features of autonomous navigation and aim low cost, integrated structure, low power consumption and compact layout. The ERADS is an integrated small 3-axis attitude sensor system with low cost and small volume. It has the Earth center measurement accuracy higher than the common IR sensor because the detected ultraviolet radiation zone of the atmosphere has a brightness gradient larger than that of the IR zone. But the ERADS is still a complex system because it has to eliminate many problems such as making of the sapphire sphere lens, birefringence effect of sapphire, high precision image transfer optical fiber flattener, ultraviolet intensifier noise, and so on. The marginal sphere FOV of the sphere lens of the ERADS is used to star imaging that may be bring some disadvantages., i.e. , the image energy and attitude measurements accuracy may be reduced due to the tilt image acceptance end of the fiber flattener in the FOV. Besides Japan, Germany and Russia developed visible earth sensor for GEO [4] [5]. Do we have a way to develop a cheaper/easier and more accurate autonomous navigation system that can be used to all LEO spacecraft, especially, to LEO small and micro satellites? To return this problem we provide a new type of the system—CANS (Compact Autonomous Navigation System) [6].

  14. Visual tracking for multi-modality computer-assisted image guidance

    Science.gov (United States)

    Basafa, Ehsan; Foroughi, Pezhman; Hossbach, Martin; Bhanushali, Jasmine; Stolka, Philipp

    2017-03-01

    With optical cameras, many interventional navigation tasks previously relying on EM, optical, or mechanical guidance can be performed robustly, quickly, and conveniently. We developed a family of novel guidance systems based on wide-spectrum cameras and vision algorithms for real-time tracking of interventional instruments and multi-modality markers. These navigation systems support the localization of anatomical targets, support placement of imaging probe and instruments, and provide fusion imaging. The unique architecture - low-cost, miniature, in-hand stereo vision cameras fitted directly to imaging probes - allows for an intuitive workflow that fits a wide variety of specialties such as anesthesiology, interventional radiology, interventional oncology, emergency medicine, urology, and others, many of which see increasing pressure to utilize medical imaging and especially ultrasound, but have yet to develop the requisite skills for reliable success. We developed a modular system, consisting of hardware (the Optical Head containing the mini cameras) and software (components for visual instrument tracking with or without specialized visual features, fully automated marker segmentation from a variety of 3D imaging modalities, visual observation of meshes of widely separated markers, instant automatic registration, and target tracking and guidance on real-time multi-modality fusion views). From these components, we implemented a family of distinct clinical and pre-clinical systems (for combinations of ultrasound, CT, CBCT, and MRI), most of which have international regulatory clearance for clinical use. We present technical and clinical results on phantoms, ex- and in-vivo animals, and patients.

  15. Constituent Aspects of Workplace Guidance in Secondary VET

    Science.gov (United States)

    Swager, Robert; Klarus, Ruud; van Merriënboer, Jeroen J. G.; Nieuwenhuis, Loek F. M.

    2015-01-01

    Purpose: This paper aims to present an integrated model of workplace guidance to enhance awareness of what constitutes good guidance, to improve workplace guidance practices in vocational education and training. Design/methodology/approach: To identify constituent aspects of workplace guidance, a systematic search of Web of Science was conducted,…

  16. Non-cable vehicle guidance

    Energy Technology Data Exchange (ETDEWEB)

    Daugela, G.C.; Willott, A.M.; Chopiuk, R.G.; Thornton, S.E.

    1988-06-01

    The purpose is to determine the most promising driverless mine vehicle guidance systems that are not dependent on buried cables, and to plan their development. The project is presented in two phases: a preliminary study and literature review to determine whether suitable technologies exist to justify further work; and an in-depth assessment and selection of technologies for vehicle guidance. A large number of guidance elements are involved in a completely automated vehicle. The technologies that hold the best potential for development of guidance systems for mine vehicles are ultrasonics, radar, lasers, dead reckoning, and guidance algorithms. The best approach to adaptation of these technologies is on a step by step basis. Guidance modules that are complete in themselves and are designed to be integrated with other modules can provide short term benefits. Two modules are selected for development: the dragline operations monitor and automated machine control for optimized mining (AMCOM). 99 refs., 20 figs., 40 tabs.

  17. An innovative information fusion method with adaptive Kalman filter for integrated INS/GPS navigation of autonomous vehicles

    Science.gov (United States)

    Liu, Yahui; Fan, Xiaoqian; Lv, Chen; Wu, Jian; Li, Liang; Ding, Dawei

    2018-02-01

    Information fusion method of INS/GPS navigation system based on filtering technology is a research focus at present. In order to improve the precision of navigation information, a navigation technology based on Adaptive Kalman Filter with attenuation factor is proposed to restrain noise in this paper. The algorithm continuously updates the measurement noise variance and processes noise variance of the system by collecting the estimated and measured values, and this method can suppress white noise. Because a measured value closer to the current time would more accurately reflect the characteristics of the noise, an attenuation factor is introduced to increase the weight of the current value, in order to deal with the noise variance caused by environment disturbance. To validate the effectiveness of the proposed algorithm, a series of road tests are carried out in urban environment. The GPS and IMU data of the experiments were collected and processed by dSPACE and MATLAB/Simulink. Based on the test results, the accuracy of the proposed algorithm is 20% higher than that of a traditional Adaptive Kalman Filter. It also shows that the precision of the integrated navigation can be improved due to the reduction of the influence of environment noise.

  18. Image guidance improves localization of sonographically occult colorectal liver metastases

    Science.gov (United States)

    Leung, Universe; Simpson, Amber L.; Adams, Lauryn B.; Jarnagin, William R.; Miga, Michael I.; Kingham, T. Peter

    2015-03-01

    Assessing the therapeutic benefit of surgical navigation systems is a challenging problem in image-guided surgery. The exact clinical indications for patients that may benefit from these systems is not always clear, particularly for abdominal surgery where image-guidance systems have failed to take hold in the same way as orthopedic and neurosurgical applications. We report interim analysis of a prospective clinical trial for localizing small colorectal liver metastases using the Explorer system (Path Finder Technologies, Nashville, TN). Colorectal liver metastases are small lesions that can be difficult to identify with conventional intraoperative ultrasound due to echogeneity changes in the liver as a result of chemotherapy and other preoperative treatments. Interim analysis with eighteen patients shows that 9 of 15 (60%) of these occult lesions could be detected with image guidance. Image guidance changed intraoperative management in 3 (17%) cases. These results suggest that image guidance is a promising tool for localization of small occult liver metastases and that the indications for image-guided surgery are expanding.

  19. Autonomous GPS/INS navigation experiment for Space Transfer Vehicle

    Science.gov (United States)

    Upadhyay, Triveni N.; Cotterill, Stephen; Deaton, A. W.

    1993-01-01

    An experiment to validate the concept of developing an autonomous integrated spacecraft navigation system using on board Global Positioning System (GPS) and Inertial Navigation System (INS) measurements is described. The feasibility of integrating GPS measurements with INS measurements to provide a total improvement in spacecraft navigation performance, i.e. improvement in position, velocity and attitude information, was previously demonstrated. An important aspect of this research is the automatic real time reconfiguration capability of the system designed to respond to changes in a spacecraft mission under the control of an expert system.

  20. Prototype of evaluation guidance system in Integrated Nuclear Data Evaluation System

    International Nuclear Information System (INIS)

    Fukahori, T.; Nakagawa, T.

    1992-01-01

    Integrated Nuclear Data Evaluation System (INDES) is being developed to keep experiences of nuclear data evaluation for JENDL-3 and to support new evaluations. One of the INDES functions is to set up input data of theoretical calculation codes automatically. In order to use INDES effectively, a prototype of nuclear data evaluation guidance system (E.T.; Evaluation Tutor) was made to help users in selecting a set of suitable theoretical calculation codes by applying knowledge engineering technology. E.T. consists of an inference engine, frames, a rule-base, two example-bases and calculating modules of certainty factors. The inference engine and the calculating modules are written in FORTRAN77. (author)

  1. How I do it-optimizing radiofrequency ablation in spinal metastases using iCT and navigation.

    Science.gov (United States)

    Kavakebi, Pujan; Freyschlag, C F; Thomé, C

    2017-10-01

    Exact positioning of the radiofrequency ablation (RFA) probe for tumor treatment under fluoroscopic guidance can be difficult because of potentially small inaccessible lesions and the radiation dose to the medical staff in RFA. In addition, vertebroplasty (VP) can be significantly high. Description and workflow of RFA in spinal metastasis using iCT (intraoperative computed tomography) and 3D-navigation-based probe placement followed by VP. RFA and VP can be successfully combined with iCT-based navigation, which leads to a reduction of radiation to the staff and optimal probe positioning due to 3D navigation.

  2. Testing Two Tools for Multimodal Navigation

    Directory of Open Access Journals (Sweden)

    Mats Liljedahl

    2012-01-01

    Full Text Available The latest smartphones with GPS, electronic compasses, directional audio, touch screens, and so forth, hold a potential for location-based services that are easier to use and that let users focus on their activities and the environment around them. Rather than interpreting maps, users can search for information by pointing in a direction and database queries can be created from GPS location and compass data. Users can also get guidance to locations through point and sweep gestures, spatial sound, and simple graphics. This paper describes two studies testing two applications with multimodal user interfaces for navigation and information retrieval. The applications allow users to search for information and get navigation support using combinations of point and sweep gestures, nonspeech audio, graphics, and text. Tests show that users appreciated both applications for their ease of use and for allowing users to interact directly with the surrounding environment.

  3. GAUSS Market Analysis for Integrated Satellite Communication and Navigation Location Based services

    Science.gov (United States)

    Di Fazio, Antonella; Dricot, Fabienne; Tata, Francesco

    2003-07-01

    The demand for mobile information services coupled with positioning technologies for delivering value- added services that depend on a user's location has rapidly increased during last years. In particular, services and applications related with improved mobility safety and transport efficiency look very attractive.Solutions for location services vary in respect of positioning accuracy and the technical infrastructure required, and the associated investment in terminals and networks. From the analysis of the state-of-the art, it comes that various technologies are currently available on the European market, while mobile industry is gearing up to launch a wide variety of location services like tracking, alarming and locating.Nevertheless, when addressing safety of life as well as security applications, severe hurdles have to be posed in the light of existing technologies. Existing navigation (e.g. GPS) and communication systems are not able to completely satisfy the needs and requirements of safety-of-life-critical applications. As a matter of fact, the GPS system's main weaknesses today is its lack of integrity, which means its inability to warn users of a malfunction in a reasonable time, while the other positioning techniques do not provide satisfactory accuracy as well, and terrestrial communication networks are not capable to cope with stringent requirement in terms of service reliability and coverage.In this context, GAUSS proposes an innovative satellite-based solution using novel technology and effective tools for addressing mobility challenges in a cost efficient manner, improving safety and effectiveness.GAUSS (Galileo And UMTS Synergetic System) is a Research and Technological Development project co- funded by European Commission, within the frame of the 5th IST Programme. The project lasted two years, and it was successfully completed in November 2002. GAUSS key concept is the integration of Satellite Navigation GNSS and UMTS communication technology, to

  4. Introducing navigation during melanoma-related sentinel lymph node procedures in the head-and-neck region.

    Science.gov (United States)

    KleinJan, Gijs H; Karakullukçu, Baris; Klop, W Martin C; Engelen, Thijs; van den Berg, Nynke S; van Leeuwen, Fijs W B

    2017-08-17

    Intraoperative sentinel node (SN) identification in patients with head-and-neck malignancies can be challenging due to unexpected drainage patterns and anatomical complexity. Here, intraoperative navigation-based guidance technologies may provide outcome. In this study, gamma camera-based freehandSPECT was evaluated in combination with the hybrid tracer ICG- 99m Tc-nanocolloid. Eight patients with melanoma located in the head-and-neck area were included. Indocyanine green (ICG)- 99m Tc-nanocolloid was injected preoperatively, whereafter lymphoscintigraphy and SPECT/CT imaging were performed in order to define the location of the SN(s). FreehandSPECT scans were generated in the operation room using a portable gamma camera. For lesion localization during surgery, freehandSPECT scans were projected in an augmented reality video-view that was used to spatially position a gamma-ray detection probe. Intraoperative fluorescence imaging was used to confirm the accuracy of the navigation-based approach and identify the exact location of the SNs. Preoperatively, 15 SNs were identified, of which 14 were identified using freehandSPECT. Navigation towards these nodes using the freehandSPECT approach was successful in 13 nodes. Fluorescence imaging provided optical confirmation of the navigation accuracy in all patients. In addition, fluorescence imaging allowed for the identification of (clustered) SNs that could not be identified based on navigation alone. The use of gamma camera-based freehandSPECT aids intraoperative lesion identification and, with that, supports the transition from pre- to intraoperative imaging via augmented reality display and directional guidance.

  5. Design of all-weather celestial navigation system

    Science.gov (United States)

    Sun, Hongchi; Mu, Rongjun; Du, Huajun; Wu, Peng

    2018-03-01

    In order to realize autonomous navigation in the atmosphere, an all-weather celestial navigation system is designed. The research of celestial navigation system include discrimination method of comentropy and the adaptive navigation algorithm based on the P value. The discrimination method of comentropy is studied to realize the independent switching of two celestial navigation modes, starlight and radio. Finally, an adaptive filtering algorithm based on P value is proposed, which can greatly improve the disturbance rejection capability of the system. The experimental results show that the accuracy of the three axis attitude is better than 10″, and it can work all weather. In perturbation environment, the position accuracy of the integrated navigation system can be increased 20% comparing with the traditional method. It basically meets the requirements of the all-weather celestial navigation system, and it has the ability of stability, reliability, high accuracy and strong anti-interference.

  6. No need for a cognitive map: decentralized memory for insect navigation.

    Directory of Open Access Journals (Sweden)

    Holk Cruse

    2011-03-01

    Full Text Available In many animals the ability to navigate over long distances is an important prerequisite for foraging. For example, it is widely accepted that desert ants and honey bees, but also mammals, use path integration for finding the way back to their home site. It is however a matter of a long standing debate whether animals in addition are able to acquire and use so called cognitive maps. Such a 'map', a global spatial representation of the foraging area, is generally assumed to allow the animal to find shortcuts between two sites although the direct connection has never been travelled before. Using the artificial neural network approach, here we develop an artificial memory system which is based on path integration and various landmark guidance mechanisms (a bank of individual and independent landmark-defined memory elements. Activation of the individual memory elements depends on a separate motivation network and an, in part, asymmetrical lateral inhibition network. The information concerning the absolute position of the agent is present, but resides in a separate memory that can only be used by the path integration subsystem to control the behaviour, but cannot be used for computational purposes with other memory elements of the system. Thus, in this simulation there is no neural basis of a cognitive map. Nevertheless, an agent controlled by this network is able to accomplish various navigational tasks known from ants and bees and often discussed as being dependent on a cognitive map. For example, map-like behaviour as observed in honey bees arises as an emergent property from a decentralized system. This behaviour thus can be explained without referring to the assumption that a cognitive map, a coherent representation of foraging space, must exist. We hypothesize that the proposed network essentially resides in the mushroom bodies of the insect brain.

  7. 3D Reconfigurable MPSoC for Unmanned Spacecraft Navigation

    Science.gov (United States)

    Dekoulis, George

    2016-07-01

    This paper describes the design of a new lightweight spacecraft navigation system for unmanned space missions. The system addresses the demands for more efficient autonomous navigation in the near-Earth environment or deep space. The proposed instrumentation is directly suitable for unmanned systems operation and testing of new airborne prototypes for remote sensing applications. The system features a new sensor technology and significant improvements over existing solutions. Fluxgate type sensors have been traditionally used in unmanned defense systems such as target drones, guided missiles, rockets and satellites, however, the guidance sensors' configurations exhibit lower specifications than the presented solution. The current implementation is based on a recently developed material in a reengineered optimum sensor configuration for unprecedented low-power consumption. The new sensor's performance characteristics qualify it for spacecraft navigation applications. A major advantage of the system is the efficiency in redundancy reduction achieved in terms of both hardware and software requirements.

  8. C-arm cone-beam CT combined with a new electromagnetic navigation system for guidance of percutaneous needle biopsies. Initial clinical experience

    Energy Technology Data Exchange (ETDEWEB)

    Kickuth, R.; Reichling, C.; Bley, T.; Hahn, D.; Ritter, C. [University Hospital of Wuerzburg (Germany). Inst. of Diagnostic and Interventional Radiology

    2015-07-15

    To evaluate the feasibility and efficacy of C-arm fluoroscopic cone-beam computed tomography (CACT) in combination with a new electromagnetic tracking (EMT) system for needle guidance during percutaneous biopsies. 53 patients were referred for biopsy of thoracic (n = 19) and abdominal (n = 34) lesions. CT-like images of the anatomical region of interest (ROI) were generated using a flat panel-based angiographic system. These images were transmitted to an EMT system. A coaxial puncture needle with a sensor in its tip was connected with the navigation system and tracked into an electromagnetic field created via a field generator. Data generated within this field were merged with the CACT images. On a monitor both the anatomical ROI and needle tip position were displayed to enable precise needle insertion into the target. Through the coaxial needle, biopsy specimens for the histologic evaluation were extracted. Number of representative biopsy samples, number of core biopsies/patient, total procedure time, dose-area product, fluoroscopic time, and complications were recorded. 53 CACT/EMT-guided biopsy procedures were performed, 48 of which (91 %) yielded representative tissue samples. Four core biopsies were obtained from each patient. 40 (75 %) lesions were malignant and 13 (25 %) lesions were benign. The total procedure time was 9 ± 5 min (range, 3 - 23 min), fluoroscopic time was 0.8 ± 0.4 min (range, 0.4 - 2 min). The mean dose-area product (cGy cm{sup 2}) was 7373 (range, 895 - 26 904). The rate of complications (1 pneumothorax, 2 hemoptyses) was 6 %. CACT combined with EMT appears to be a feasible and effective technique for the guidance of percutaneous biopsies with a low rate of therapeutically relevant complications.

  9. C-arm cone-beam CT combined with a new electromagnetic navigation system for guidance of percutaneous needle biopsies. Initial clinical experience

    International Nuclear Information System (INIS)

    Kickuth, R.; Reichling, C.; Bley, T.; Hahn, D.; Ritter, C.

    2015-01-01

    To evaluate the feasibility and efficacy of C-arm fluoroscopic cone-beam computed tomography (CACT) in combination with a new electromagnetic tracking (EMT) system for needle guidance during percutaneous biopsies. 53 patients were referred for biopsy of thoracic (n = 19) and abdominal (n = 34) lesions. CT-like images of the anatomical region of interest (ROI) were generated using a flat panel-based angiographic system. These images were transmitted to an EMT system. A coaxial puncture needle with a sensor in its tip was connected with the navigation system and tracked into an electromagnetic field created via a field generator. Data generated within this field were merged with the CACT images. On a monitor both the anatomical ROI and needle tip position were displayed to enable precise needle insertion into the target. Through the coaxial needle, biopsy specimens for the histologic evaluation were extracted. Number of representative biopsy samples, number of core biopsies/patient, total procedure time, dose-area product, fluoroscopic time, and complications were recorded. 53 CACT/EMT-guided biopsy procedures were performed, 48 of which (91 %) yielded representative tissue samples. Four core biopsies were obtained from each patient. 40 (75 %) lesions were malignant and 13 (25 %) lesions were benign. The total procedure time was 9 ± 5 min (range, 3 - 23 min), fluoroscopic time was 0.8 ± 0.4 min (range, 0.4 - 2 min). The mean dose-area product (cGy cm 2 ) was 7373 (range, 895 - 26 904). The rate of complications (1 pneumothorax, 2 hemoptyses) was 6 %. CACT combined with EMT appears to be a feasible and effective technique for the guidance of percutaneous biopsies with a low rate of therapeutically relevant complications.

  10. The Application of Surgical Navigation in the Treatment of Temporomandibular Joint Ankylosis.

    Science.gov (United States)

    Sun, Guowen; Lu, Mingxing; Hu, Qingang

    2015-11-01

    The purpose of this study was to assess the safety and the accuracy of surgical navigation technology in the resection of severe ankylosis of the mandibular condyle with the middle cranial fossa. The computed tomography scan data were transferred to a Windows-based computer workstation, and the patient's individual anatomy was assessed in multiplanar views at the workstation. In the operation, the patient and the virtual image were matched by individual registration with the reference points which were set on the skull bone surface and the teeth. Then, the real-time navigation can be performed. The acquisition of the data sets was uncomplicated, and image quality was sufficient to assess the operative result in 2 cases. Both of the operations were performed successfully with the guidance of real-time navigation. The application of surgical navigation has enhanced the safety and the accuracy of the surgery for bony ankylosis of temporomandibular joint. The use of surgical navigation resulted in the promotion of accurate and safe surgical excision of the ankylosed skull base tissue.

  11. Overcoming urban GPS navigation challenges through the use of MEMS inertial sensors and proper verification of navigation system performance

    Science.gov (United States)

    Vinande, Eric T.

    This research proposes several means to overcome challenges in the urban environment to ground vehicle global positioning system (GPS) receiver navigation performance through the integration of external sensor information. The effects of narrowband radio frequency interference and signal attenuation, both common in the urban environment, are examined with respect to receiver signal tracking processes. Low-cost microelectromechanical systems (MEMS) inertial sensors, suitable for the consumer market, are the focus of receiver augmentation as they provide an independent measure of motion and are independent of vehicle systems. A method for estimating the mounting angles of an inertial sensor cluster utilizing typical urban driving maneuvers is developed and is able to provide angular measurements within two degrees of truth. The integration of GPS and MEMS inertial sensors is developed utilizing a full state navigation filter. Appropriate statistical methods are developed to evaluate the urban environment navigation improvement due to the addition of MEMS inertial sensors. A receiver evaluation metric that combines accuracy, availability, and maximum error measurements is presented and evaluated over several drive tests. Following a description of proper drive test techniques, record and playback systems are evaluated as the optimal way of testing multiple receivers and/or integrated navigation systems in the urban environment as they simplify vehicle testing requirements.

  12. Autonomous GPS/INS navigation experiment for Space Transfer Vehicle (STV)

    Science.gov (United States)

    Upadhyay, Triveni N.; Cotterill, Stephen; Deaton, A. Wayne

    1991-01-01

    An experiment to validate the concept of developing an autonomous integrated spacecraft navigation system using on board Global Positioning System (GPS) and Inertial Navigation System (INS) measurements is described. The feasibility of integrating GPS measurements with INS measurements to provide a total improvement in spacecraft navigation performance, i.e. improvement in position, velocity and attitude information, was previously demonstrated. An important aspect of this research is the automatic real time reconfiguration capability of the system designed to respond to changes in a spacecraft mission under the control of an expert system.

  13. Designation and verification of road markings detection and guidance method

    Science.gov (United States)

    Wang, Runze; Jian, Yabin; Li, Xiyuan; Shang, Yonghong; Wang, Jing; Zhang, JingChuan

    2018-01-01

    With the rapid development of China's space industry, digitization and intelligent is the tendency of the future. This report is present a foundation research about guidance system which based on the HSV color space. With the help of these research which will help to design the automatic navigation and parking system for the frock transport car and the infrared lamp homogeneity intelligent test equipment. The drive mode, steer mode as well as the navigation method was selected. In consideration of the practicability, it was determined to use the front-wheel-steering chassis. The steering mechanism was controlled by the stepping motors, and it is guided by Machine Vision. The optimization and calibration of the steering mechanism was made. A mathematical model was built and the objective functions was constructed for the steering mechanism. The extraction method of the steering line was studied and the motion controller was designed and optimized. The theory of HSV, RGB color space and analysis of the testing result will be discussed Using the function library OPENCV on the Linux system to fulfill the camera calibration. Based on the HSV color space to design the guidance algorithm.

  14. Vision Based Navigation for Autonomous Cooperative Docking of CubeSats

    Science.gov (United States)

    Pirat, Camille; Ankersen, Finn; Walker, Roger; Gass, Volker

    2018-05-01

    A realistic rendezvous and docking navigation solution applicable to CubeSats is investigated. The scalability analysis of the ESA Autonomous Transfer Vehicle Guidance, Navigation & Control (GNC) performances and the Russian docking system, shows that the docking of two CubeSats would require a lateral control performance of the order of 1 cm. Line of sight constraints and multipath effects affecting Global Navigation Satellite System (GNSS) measurements in close proximity prevent the use of this sensor for the final approach. This consideration and the high control accuracy requirement led to the use of vision sensors for the final 10 m of the rendezvous and docking sequence. A single monocular camera on the chaser satellite and various sets of Light-Emitting Diodes (LEDs) on the target vehicle ensure the observability of the system throughout the approach trajectory. The simple and novel formulation of the measurement equations allows differentiating unambiguously rotations from translations between the target and chaser docking port and allows a navigation performance better than 1 mm at docking. Furthermore, the non-linear measurement equations can be solved in order to provide an analytic navigation solution. This solution can be used to monitor the navigation filter solution and ensure its stability, adding an extra layer of robustness for autonomous rendezvous and docking. The navigation filter initialization is addressed in detail. The proposed method is able to differentiate LEDs signals from Sun reflections as demonstrated by experimental data. The navigation filter uses a comprehensive linearised coupled rotation/translation dynamics, describing the chaser to target docking port motion. The handover, between GNSS and vision sensor measurements, is assessed. The performances of the navigation function along the approach trajectory is discussed.

  15. Distributed cooperative guidance for multiple missiles with fixed and switching communication topologies

    Directory of Open Access Journals (Sweden)

    Qilun ZHAO

    2017-08-01

    Full Text Available This study investigates cooperative guidance problems for multiple missiles with fixed and switching directed communication topologies. A two-step guidance strategy is proposed to realize the simultaneous attack. In the first step, a distributed cooperative guidance law is designed using local neighboring information for multiple missiles to achieve consensus on range-to-go and leading angle. The second step begins when the consensus of multiple missiles is realized. During the second step, multiple missiles disconnect from each other and hit the target using the proportional navigation guidance law. First, based on the local neighboring communications, a sufficient condition for multiple missiles to realize simultaneous attack with a fixed communication topology is presented, where the topology is only required to have a directed spanning tree. Then, the results are extended to the case of switching communication topologies. Finally, numerical simulations are provided to validate the theoretical results.

  16. PERFORMANCE CHARACTERISTIC MEMS-BASED IMUs FOR UAVs NAVIGATION

    Directory of Open Access Journals (Sweden)

    H. A. Mohamed

    2015-08-01

    Full Text Available Accurate 3D reconstruction has become essential for non-traditional mapping applications such as urban planning, mining industry, environmental monitoring, navigation, surveillance, pipeline inspection, infrastructure monitoring, landslide hazard analysis, indoor localization, and military simulation. The needs of these applications cannot be satisfied by traditional mapping, which is based on dedicated data acquisition systems designed for mapping purposes. Recent advances in hardware and software development have made it possible to conduct accurate 3D mapping without using costly and high-end data acquisition systems. Low-cost digital cameras, laser scanners, and navigation systems can provide accurate mapping if they are properly integrated at the hardware and software levels. Unmanned Aerial Vehicles (UAVs are emerging as a mobile mapping platform that can provide additional economical and practical advantages. However, such economical and practical requirements need navigation systems that can provide uninterrupted navigation solution. Hence, testing the performance characteristics of Micro-Electro-Mechanical Systems (MEMS or low cost navigation sensors for various UAV applications is important research. This work focuses on studying the performance characteristics under different manoeuvres using inertial measurements integrated with single point positioning, Real-Time-Kinematic (RTK, and additional navigational aiding sensors. Furthermore, the performance of the inertial sensors is tested during Global Positioning System (GPS signal outage.

  17. Performance Characteristic Mems-Based IMUs for UAVs Navigation

    Science.gov (United States)

    Mohamed, H. A.; Hansen, J. M.; Elhabiby, M. M.; El-Sheimy, N.; Sesay, A. B.

    2015-08-01

    Accurate 3D reconstruction has become essential for non-traditional mapping applications such as urban planning, mining industry, environmental monitoring, navigation, surveillance, pipeline inspection, infrastructure monitoring, landslide hazard analysis, indoor localization, and military simulation. The needs of these applications cannot be satisfied by traditional mapping, which is based on dedicated data acquisition systems designed for mapping purposes. Recent advances in hardware and software development have made it possible to conduct accurate 3D mapping without using costly and high-end data acquisition systems. Low-cost digital cameras, laser scanners, and navigation systems can provide accurate mapping if they are properly integrated at the hardware and software levels. Unmanned Aerial Vehicles (UAVs) are emerging as a mobile mapping platform that can provide additional economical and practical advantages. However, such economical and practical requirements need navigation systems that can provide uninterrupted navigation solution. Hence, testing the performance characteristics of Micro-Electro-Mechanical Systems (MEMS) or low cost navigation sensors for various UAV applications is important research. This work focuses on studying the performance characteristics under different manoeuvres using inertial measurements integrated with single point positioning, Real-Time-Kinematic (RTK), and additional navigational aiding sensors. Furthermore, the performance of the inertial sensors is tested during Global Positioning System (GPS) signal outage.

  18. Space Shuttle Guidance, Navigation, and Rendezvous Knowledge Capture Reports. Revision 1

    Science.gov (United States)

    Goodman, John L.

    2011-01-01

    This document is a catalog and readers guide to lessons learned, experience, and technical history reports, as well as compilation volumes prepared by United Space Alliance personnel for the NASA/Johnson Space Center (JSC) Flight Dynamics Division.1 It is intended to make it easier for future generations of engineers to locate knowledge capture documentation from the Shuttle Program. The first chapter covers observations on documentation quality and research challenges encountered during the Space Shuttle and Orion programs. The second chapter covers the knowledge capture approach used to create many of the reports covered in this document. These chapters are intended to provide future flight programs with insight that could be used to formulate knowledge capture and management strategies. The following chapters contain descriptions of each knowledge capture report. The majority of the reports concern the Space Shuttle. Three are included that were written in support of the Orion Program. Most of the reports were written from the years 2001 to 2011. Lessons learned reports concern primarily the shuttle Global Positioning System (GPS) upgrade and the knowledge capture process. Experience reports on navigation and rendezvous provide examples of how challenges were overcome and how best practices were identified and applied. Some reports are of a more technical history nature covering navigation and rendezvous. They provide an overview of mission activities and the evolution of operations concepts and trajectory design. The lessons learned, experience, and history reports would be considered secondary sources by historians and archivists.

  19. Intraoperative magnetic resonance imaging to update interactive navigation in neurosurgery: method and preliminary experience.

    Science.gov (United States)

    Wirtz, C R; Bonsanto, M M; Knauth, M; Tronnier, V M; Albert, F K; Staubert, A; Kunze, S

    1997-01-01

    We report on the first successful intraoperative update of interactive image guidance based on an intraoperatively acquired magnetic resonance imaging (MRI) date set. To date, intraoperative imaging methods such as ultrasound, computerized tomography (CT), or MRI have not been successfully used to update interactive navigation. We developed a method of imaging patients intraoperatively with the surgical field exposed in an MRI scanner (Magnetom Open; Siemens Corp., Erlangen, Germany). In 12 patients, intraoperatively acquired 3D data sets were used for successful recalibration of neuronavigation, accounting for any anatomical changes caused by surgical manipulations. The MKM Microscope (Zeiss Corp., Oberkochen, Germany) was used as navigational system. With implantable fiducial markers, an accuracy of 0.84 +/- 0.4 mm for intraoperative reregistration was achieved. Residual tumor detected on MRI was consequently resected using navigation with the intraoperative data. No adverse effects were observed from intraoperative imaging or the use of navigation with intraoperative images, demonstrating the feasibility of recalibrating navigation with intraoperative MRI.

  20. Ontology-centric integration and navigation of the dengue literature.

    Science.gov (United States)

    Rajapakse, Menaka; Kanagasabai, Rajaraman; Ang, Wee Tiong; Veeramani, Anitha; Schreiber, Mark J; Baker, Christopher J O

    2008-10-01

    Uninhibited access to the unstructured information distributed across the web and in scientific literature databases continues to be beyond the reach of scientists and health professionals. To address this challenge we have developed a literature driven, ontology-centric navigation infrastructure consisting of a content acquisition engine, a domain-specific ontology (in OWL-DL) and an ontology instantiation pipeline delivering sentences derived by domain-specific text mining. A visual query tool for reasoning over A-box instances in the populated ontology is presented and used to build conceptual queries that can be issued to the knowledgebase. We have deployed this generic infrastructure to facilitate data integration and knowledge sharing in the domain of dengue, which is one of the most prevalent viral diseases that continue to infect millions of people in the tropical and subtropical regions annually. Using our unique methodology we illustrate simplified search and discovery on dengue information derived from distributed resources and aggregated according to dengue ontology. Furthermore we apply data mining to the instantiated ontology to elucidate trends in the mentions of dengue serotypes in scientific abstracts since 1974.

  1. Guidance system operations plan for manned CM earth orbital missions using program SKYLARK 1. Section 4: Operational modes

    Science.gov (United States)

    Dunbar, J. C.

    1972-01-01

    The operational modes for the guidance system operations plan for Program SKYLARK 1 are presented. The procedures control the guidance and navigation system interfaces with the flight crew and the mission control center. The guidance operational concept is designed to comprise a set of manually initiated programs and functions which may be arranged by the flight crew to implement a large class of flight plans. This concept will permit both a late flight plan definition and a capability for real time flight plan changes.

  2. Crosswell Imaging Technology & Advanced DSR Navigation for Horizontal Directional Drilling

    Energy Technology Data Exchange (ETDEWEB)

    Larry Stolarczyk

    2008-08-08

    The objective of Phase II is to develop and demonstrate real-time measurement-while-drilling (MWD) for guidance and navigation of drill strings during horizontal drilling operations applicable to both short and long holes. The end product of Phase II is a functional drill-string assembly outfitted with a commercial version of Drill String Radar (DSR). Project Objectives Develop and demonstrate a dual-phase methodology of in-seam drilling, imaging, and structure confirmation. This methodology, illustrated in Figure 1, includes: (1) Using RIM to image between drill holes for seam thickness estimates and in-seam structures detection. Completed, February 2005; and (2) Using DSR for real-time MWD guidance and navigation of drillstrings during horizontal drilling operations. Completed, November 2008. As of November 2008, the Phase II portion of Contract DE-FC26-04NT42085 is about 99% complete, including milestones and tasks original outlined as Phase II work. The one percent deficiency results from MSHA-related approvals which have yet to be granted (at the time of reporting). These approvals are pending and are do not negatively impact the scope of work or project objectives.

  3. Amblypygids: Model Organisms for the Study of Arthropod Navigation Mechanisms in Complex Environments?

    Directory of Open Access Journals (Sweden)

    Daniel D Wiegmann

    2016-03-01

    Full Text Available Navigation is an ideal behavioral model for the study of sensory system integration and the neural substrates associated with complex behavior. For this broader purpose, however, it may be profitable to develop new model systems that are both tractable and sufficiently complex to ensure that information derived from a single sensory modality and path integration are inadequate to locate a goal. Here, we discuss some recent discoveries related to navigation by amblypygids, nocturnal arachnids that inhabit the tropics and sub-tropics. Nocturnal displacement experiments under the cover of a tropical rainforest reveal that these animals possess navigational abilities that are reminiscent, albeit on a smaller spatial scale, of true-navigating vertebrates. Specialized legs, called antenniform legs, which possess hundreds of olfactory and tactile sensory hairs, and vision appear to be involved. These animals also have enormous mushroom bodies, higher-order brain regions that, in insects, integrate contextual cues and may be involved in spatial memory. In amblypygids, the complexity of a nocturnal rainforest may impose navigational challenges that favor the integration of information derived from multimodal cues. Moreover, the movement of these animals is easily studied in the laboratory and putative neural integration sites of sensory information can be manipulated. Thus, amblypygids could serve as a model system for the discovery of neural substrates associated with a unique and potentially sophisticated navigational capability. The diversity of habitats in which amblypygids are found also offers an opportunity for comparative studies of sensory integration and ecological selection pressures on navigation mechanisms.

  4. Autonomous vision-based navigation for proximity operations around binary asteroids

    Science.gov (United States)

    Gil-Fernandez, Jesus; Ortega-Hernando, Guillermo

    2018-06-01

    Future missions to small bodies demand higher level of autonomy in the Guidance, Navigation and Control system for higher scientific return and lower operational costs. Different navigation strategies have been assessed for ESA's asteroid impact mission (AIM). The main objective of AIM is the detailed characterization of binary asteroid Didymos. The trajectories for the proximity operations shall be intrinsically safe, i.e., no collision in presence of failures (e.g., spacecraft entering safe mode), perturbations (e.g., non-spherical gravity field), and errors (e.g., maneuver execution error). Hyperbolic arcs with sufficient hyperbolic excess velocity are designed to fulfil the safety, scientific, and operational requirements. The trajectory relative to the asteroid is determined using visual camera images. The ground-based trajectory prediction error at some points is comparable to the camera Field Of View (FOV). Therefore, some images do not contain the entire asteroid. Autonomous navigation can update the state of the spacecraft relative to the asteroid at higher frequency. The objective of the autonomous navigation is to improve the on-board knowledge compared to the ground prediction. The algorithms shall fit in off-the-shelf, space-qualified avionics. This note presents suitable image processing and relative-state filter algorithms for autonomous navigation in proximity operations around binary asteroids.

  5. Adaptive Landmark-Based Navigation System Using Learning Techniques

    DEFF Research Database (Denmark)

    Zeidan, Bassel; Dasgupta, Sakyasingha; Wörgötter, Florentin

    2014-01-01

    The goal-directed navigational ability of animals is an essential prerequisite for them to survive. They can learn to navigate to a distal goal in a complex environment. During this long-distance navigation, they exploit environmental features, like landmarks, to guide them towards their goal. In...... hexapod robots. As a result, it allows the robots to successfully learn to navigate to distal goals in complex environments.......The goal-directed navigational ability of animals is an essential prerequisite for them to survive. They can learn to navigate to a distal goal in a complex environment. During this long-distance navigation, they exploit environmental features, like landmarks, to guide them towards their goal....... Inspired by this, we develop an adaptive landmark-based navigation system based on sequential reinforcement learning. In addition, correlation-based learning is also integrated into the system to improve learning performance. The proposed system has been applied to simulated simple wheeled and more complex...

  6. Using the framework of corporate culture in "mergers" to support the development of a cultural basis for integrative medicine - guidance for building an integrative medicine department or service.

    Science.gov (United States)

    Witt, Claudia M; Pérard, Marion; Berman, Brian; Berman, Susan; Birdsall, Timothy C; Defren, Horst; Kümmel, Sherko; Deng, Gary; Dobos, Gustav; Drexler, Atje; Holmberg, Christine; Horneber, Markus; Jütte, Robert; Knutson, Lori; Kummer, Christopher; Volpers, Susanne; Schweiger, David

    2015-01-01

    An increasing number of clinics offer complementary or integrative medicine services; however, clear guidance about how complementary medicine could be successfully and efficiently integrated into conventional health care settings is still lacking. Combining conventional and complementary medicine into integrative medicine can be regarded as a kind of merger. In a merger, two or more organizations - usually companies - are combined into one in order to strengthen the companies financially and strategically. The corporate culture of both merger partners has an important influence on the integration. The aim of this project was to transfer the concept of corporate culture in mergers to the merging of two medical systems. A two-step approach (literature analyses and expert consensus procedure) was used to develop practical guidance for the development of a cultural basis for integrative medicine, based on the framework of corporate culture in "mergers," which could be used to build an integrative medicine department or integrative medicine service. Results include recommendations for general strategic dimensions (definition of the medical model, motivation for integration, clarification of the available resources, development of the integration team, and development of a communication strategy), and recommendations to overcome cultural differences (the clinic environment, the professional language, the professional image, and the implementation of evidence-based medicine). The framework of mergers in corporate culture provides an understanding of the difficulties involved in integrative medicine projects. The specific recommendations provide a good basis for more efficient implementation.

  7. Real-time in situ three-dimensional integral videography and surgical navigation using augmented reality: a pilot study

    Science.gov (United States)

    Suenaga, Hideyuki; Hoang Tran, Huy; Liao, Hongen; Masamune, Ken; Dohi, Takeyoshi; Hoshi, Kazuto; Mori, Yoshiyuki; Takato, Tsuyoshi

    2013-01-01

    To evaluate the feasibility and accuracy of a three-dimensional augmented reality system incorporating integral videography for imaging oral and maxillofacial regions, based on preoperative computed tomography data. Three-dimensional surface models of the jawbones, based on the computed tomography data, were used to create the integral videography images of a subject's maxillofacial area. The three-dimensional augmented reality system (integral videography display, computed tomography, a position tracker and a computer) was used to generate a three-dimensional overlay that was projected on the surgical site via a half-silvered mirror. Thereafter, a feasibility study was performed on a volunteer. The accuracy of this system was verified on a solid model while simulating bone resection. Positional registration was attained by identifying and tracking the patient/surgical instrument's position. Thus, integral videography images of jawbones, teeth and the surgical tool were superimposed in the correct position. Stereoscopic images viewed from various angles were accurately displayed. Change in the viewing angle did not negatively affect the surgeon's ability to simultaneously observe the three-dimensional images and the patient, without special glasses. The difference in three-dimensional position of each measuring point on the solid model and augmented reality navigation was almost negligible (augmented reality system was highly accurate and effective for surgical navigation and for overlaying a three-dimensional computed tomography image on a patient's surgical area, enabling the surgeon to understand the positional relationship between the preoperative image and the actual surgical site, with the naked eye. PMID:23703710

  8. Seamless Guidance System Combining GPS, BLE Beacon, and NFC Technologies

    Directory of Open Access Journals (Sweden)

    Rung-Shiang Cheng

    2016-01-01

    Full Text Available Users rely increasingly on Location-Based Services (LBS and automated navigation/guidance systems nowadays. However, while such services are easily implemented in outdoor environments using Global Positioning System (GPS technology, a requirement still exists for accurate localization and guidance schemes in indoor settings. Accordingly, the present study proposes a system based on GPS, Bluetooth Low Energy (BLE beacons, and Near Field Communication (NFC technology. Through establishing graphic information and the design of algorithm, this study develops a guidance system for indoors and outdoors on smart phones, wishing to give user perfect smart life through this system. The proposed system is implemented on a smart phone and evaluated on a student campus environment. The experimental results confirm the ability of the proposed app to switch automatically from an outdoor mode to an indoor mode and to guide the user to requested target destination via the shortest possible route.

  9. A Neurocomputational Model of Goal-Directed Navigation in Insect-Inspired Artificial Agents.

    Science.gov (United States)

    Goldschmidt, Dennis; Manoonpong, Poramate; Dasgupta, Sakyasingha

    2017-01-01

    Despite their small size, insect brains are able to produce robust and efficient navigation in complex environments. Specifically in social insects, such as ants and bees, these navigational capabilities are guided by orientation directing vectors generated by a process called path integration. During this process, they integrate compass and odometric cues to estimate their current location as a vector, called the home vector for guiding them back home on a straight path. They further acquire and retrieve path integration-based vector memories globally to the nest or based on visual landmarks. Although existing computational models reproduced similar behaviors, a neurocomputational model of vector navigation including the acquisition of vector representations has not been described before. Here we present a model of neural mechanisms in a modular closed-loop control-enabling vector navigation in artificial agents. The model consists of a path integration mechanism, reward-modulated global learning, random search, and action selection. The path integration mechanism integrates compass and odometric cues to compute a vectorial representation of the agent's current location as neural activity patterns in circular arrays. A reward-modulated learning rule enables the acquisition of vector memories by associating the local food reward with the path integration state. A motor output is computed based on the combination of vector memories and random exploration. In simulation, we show that the neural mechanisms enable robust homing and localization, even in the presence of external sensory noise. The proposed learning rules lead to goal-directed navigation and route formation performed under realistic conditions. Consequently, we provide a novel approach for vector learning and navigation in a simulated, situated agent linking behavioral observations to their possible underlying neural substrates.

  10. Outer navigation of a inspection robot by means of feedback of global guidance; Navegacion exterior de un robot de inspeccion mediante retroalimentacion de la orientacion global

    Energy Technology Data Exchange (ETDEWEB)

    Segovia de los R, A.; Bucio V, F. [ININ, 52750 La Marquesa, Estado de Mexico (Mexico); Garduno G, M. [Instituto Tecnologico de Toluca, Av. Instituto Tecnologico s/n, Metepec, Estado de Mexico 52140 (Mexico)]. e-mail: asegovia@nuclear.inin.mx

    2008-07-01

    The objective of this article is the presentation of an inspection system to mobile robot navigating in exteriors by means of the employment of a feedback of instantaneous guidance with respect to a global reference throughout moment of the displacement. The robot evolves obeying the commands coming from the one tele operator which indicates the diverse addresses by means of the operation console that the robot should take using for it information provided by an electronic compass. The mobile robot employee in the experimentations is a Pioneer 3-AT, which counts with a sensor series required to obtain an operation of more autonomy. The electronic compass offers geographical information coded in a format SPI, reason for which a micro controller ({mu}C) economic of general use has been an employee for to transfer the information to the format RS-232, originally used by the Pioneer 3-AT. The orientation information received by the robot by means of their serial port RS-232 secondary it is forwarded to the computer hostess in the one which a program Java is used to generate the commands for the robot navigation control and to deploy one graphic interface user utilized to receive the order of the operator. This research is part of an ambitious project in which it is tried to count on an inspection system and monitoring of sites in which risks of high radiation levels could exist, thus a navigation systems in exteriors could be very useful. The complete system will count besides the own sensors of the robot, with certain numbers of agree sensors to the variables that are desired to monitor. The resulting values of such measurements will be visualized in real time in the graphic interface user, thanks to a bidirectional wireless communication among the station of operation and the mobile robot. (Author)

  11. Instrument-mounted displays for reducing cognitive load during surgical navigation.

    Science.gov (United States)

    Herrlich, Marc; Tavakol, Parnian; Black, David; Wenig, Dirk; Rieder, Christian; Malaka, Rainer; Kikinis, Ron

    2017-09-01

    Surgical navigation systems rely on a monitor placed in the operating room to relay information. Optimal monitor placement can be challenging in crowded rooms, and it is often not possible to place the monitor directly beside the situs. The operator must split attention between the navigation system and the situs. We present an approach for needle-based interventions to provide navigational feedback directly on the instrument and close to the situs by mounting a small display onto the needle. By mounting a small and lightweight smartwatch display directly onto the instrument, we are able to provide navigational guidance close to the situs and directly in the operator's field of view, thereby reducing the need to switch the focus of view between the situs and the navigation system. We devise a specific variant of the established crosshair metaphor suitable for the very limited screen space. We conduct an empirical user study comparing our approach to using a monitor and a combination of both. Results from the empirical user study show significant benefits for cognitive load, user preference, and general usability for the instrument-mounted display, while achieving the same level of performance in terms of time and accuracy compared to using a monitor. We successfully demonstrate the feasibility of our approach and potential benefits. With ongoing technological advancements, instrument-mounted displays might complement standard monitor setups for surgical navigation in order to lower cognitive demands and for improved usability of such systems.

  12. Intelligence Context Aware Mobile Navigation using Augmented Reality Technology

    Directory of Open Access Journals (Sweden)

    Ahmad Hoirul Basori

    2018-04-01

    Full Text Available Most of the technologies of today’s world, which are enriched with various powerful features and amazing quality characteristics, enables software developers to come up with best possible software solutions, no matter what the context of the particular issue. Technologies such as Augmented Reality (AR, is utilized almost every kind of fields in today’s society. As computers become more advanced through mobile devices and wearable technology, augmented reality will become a seamless experience that is a part of our everyday lives. In the context of this work, an Intelligence mobile navigation application for the King Abdul Aziz University Rabigh is developed enabling the user to find specific locations on campus and offers the ability to explore the campus environment via AR. Furthermore, the system, Mobile Campus Navigation with Augmented Reality application is capable of giving guidance in outdoor location navigating and retrieving details of campus officials and lecturers. With the proposed system, it is expected to serve as a useful and informative navigate helper for both students of King Abdul Aziz University and for the visitors, at outdoor locations and to use as an application to check officials and lecturer availability and retrieve detail about them when they are not available at the office at any time.

  13. Electromagnetic navigation diagnostic bronchoscopy for small peripheral lung lesions.

    Science.gov (United States)

    Makris, D; Scherpereel, A; Leroy, S; Bouchindhomme, B; Faivre, J-B; Remy, J; Ramon, P; Marquette, C-H

    2007-06-01

    The present study prospectively evaluated the diagnostic yield and safety of electromagnetic navigation-guided bronchoscopy biopsy, for small peripheral lung lesions in patients where standard techniques were nondiagnostic. The study was conducted in a tertiary medical centre on 40 consecutive patients considered unsuitable for straightforward surgery or computed tomography (CT)-guided transthoracic needle aspiration biopsy, due to comorbidities. The lung lesion diameter was mean+/-sem 23.5+/-1.5 mm and the depth from the visceral-costal pleura was 14.9+/-2 mm. Navigation was facilitated by an electromagnetic tracking system which could detect a position sensor incorporated into a flexible catheter advanced through a bronchoscope. Information obtained during bronchoscopy was superimposed on previously acquired CT data. Divergence between CT data and data obtained during bronchoscopy was calculated by the system's software as a measure of navigational accuracy. All but one of the target lesions was reached and the overall diagnostic yield was 62.5% (25-40). Diagnostic yield was significantly affected by CT-to-body divergence; yield was 77.2% when estimated divergence was drainage was required in one case. Electromagnetic navigation-guided bronchoscopy has the potential to improve the diagnostic yield of transbronchial biopsies without additional fluoroscopic guidance, and may be useful in the early diagnosis of lung cancer, particularly in nonoperable patients.

  14. Clarification of the Use of Biological Data and Information in the 2002 Integrated Water Quality Monitoring and Assessment Report Guidance

    Science.gov (United States)

    The memorandum modifies the 2002 Integrated Water Quality Monitoring and Assessment Report Guidance to provide clarity and promote consistency in the manner in which states use biological data and information in developing their 2002 submissions.

  15. GPS navigation algorithms for Autonomous Airborne Refueling of Unmanned Air Vehicles

    Science.gov (United States)

    Khanafseh, Samer Mahmoud

    Unmanned Air Vehicles (UAVs) have recently generated great interest because of their potential to perform hazardous missions without risking loss of life. If autonomous airborne refueling is possible for UAVs, mission range and endurance will be greatly enhanced. However, concerns about UAV-tanker proximity, dynamic mobility and safety demand that the relative navigation system meets stringent requirements on accuracy, integrity, and continuity. In response, this research focuses on developing high-performance GPS-based navigation architectures for Autonomous Airborne Refueling (AAR) of UAVs. The AAR mission is unique because of the potentially severe sky blockage introduced by the tanker. To address this issue, a high-fidelity dynamic sky blockage model was developed and experimentally validated. In addition, robust carrier phase differential GPS navigation algorithms were derived, including a new method for high-integrity reacquisition of carrier cycle ambiguities for recently-blocked satellites. In order to evaluate navigation performance, world-wide global availability and sensitivity covariance analyses were conducted. The new navigation algorithms were shown to be sufficient for turn-free scenarios, but improvement in performance was necessary to meet the difficult requirements for a general refueling mission with banked turns. Therefore, several innovative methods were pursued to enhance navigation performance. First, a new theoretical approach was developed to quantify the position-domain integrity risk in cycle ambiguity resolution problems. A mechanism to implement this method with partially-fixed cycle ambiguity vectors was derived, and it was used to define tight upper bounds on AAR navigation integrity risk. A second method, where a new algorithm for optimal fusion of measurements from multiple antennas was developed, was used to improve satellite coverage in poor visibility environments such as in AAR. Finally, methods for using data-link extracted

  16. Honeybees as a model for the study of visually guided flight, navigation, and biologically inspired robotics.

    Science.gov (United States)

    Srinivasan, Mandyam V

    2011-04-01

    Research over the past century has revealed the impressive capacities of the honeybee, Apis mellifera, in relation to visual perception, flight guidance, navigation, and learning and memory. These observations, coupled with the relative ease with which these creatures can be trained, and the relative simplicity of their nervous systems, have made honeybees an attractive model in which to pursue general principles of sensorimotor function in a variety of contexts, many of which pertain not just to honeybees, but several other animal species, including humans. This review begins by describing the principles of visual guidance that underlie perception of the world in three dimensions, obstacle avoidance, control of flight speed, and orchestrating smooth landings. We then consider how navigation over long distances is accomplished, with particular reference to how bees use information from the celestial compass to determine their flight bearing, and information from the movement of the environment in their eyes to gauge how far they have flown. Finally, we illustrate how some of the principles gleaned from these studies are now being used to design novel, biologically inspired algorithms for the guidance of unmanned aerial vehicles.

  17. TIPsy tour guides: How microtubule plus-end tracking proteins (+TIPs facilitate axon guidance

    Directory of Open Access Journals (Sweden)

    Elizabeth A Bearce

    2015-06-01

    Full Text Available The growth cone is a dynamic cytoskeletal vehicle, which drives the end of a developing axon. It serves to interpret and navigate through the complex landscape and guidance cues of the early nervous system. The growth cone’s distinctive cytoskeletal organization offers a fascinating platform to study how extracellular cues can be translated into mechanical outgrowth and turning behaviors. While many studies of cell motility highlight the importance of actin networks in signaling, adhesion, and propulsion, both seminal and emerging works in the field have highlighted a unique and necessary role for microtubules in growth cone navigation. Here, we focus on the role of singular pioneer microtubules, which extend into the growth cone periphery and are regulated by a diverse family of microtubule plus-end tracking proteins (+TIPs. These +TIPs accumulate at the dynamic ends of microtubules, where they are well-positioned to encounter and respond to key signaling events downstream of guidance receptors, catalyzing immediate changes in microtubule stability and actin cross-talk, that facilitate both axonal outgrowth and turning events.

  18. Location Accuracy of INS/Gravity-Integrated Navigation System on the Basis of Ocean Experiment and Simulation.

    Science.gov (United States)

    Wang, Hubiao; Wu, Lin; Chai, Hua; Bao, Lifeng; Wang, Yong

    2017-12-20

    An experiment comparing the location accuracy of gravity matching-aided navigation in the ocean and simulation is very important to evaluate the feasibility and the performance of an INS/gravity-integrated navigation system (IGNS) in underwater navigation. Based on a 1' × 1' marine gravity anomaly reference map and multi-model adaptive Kalman filtering algorithm, a matching location experiment of IGNS was conducted using data obtained using marine gravimeter. The location accuracy under actual ocean conditions was 2.83 nautical miles (n miles). Several groups of simulated data of marine gravity anomalies were obtained by establishing normally distributed random error N ( u , σ 2 ) with varying mean u and noise variance σ 2 . Thereafter, the matching location of IGNS was simulated. The results show that the changes in u had little effect on the location accuracy. However, an increase in σ 2 resulted in a significant decrease in the location accuracy. A comparison between the actual ocean experiment and the simulation along the same route demonstrated the effectiveness of the proposed simulation method and quantitative analysis results. In addition, given the gravimeter (1-2 mGal accuracy) and the reference map (resolution 1' × 1'; accuracy 3-8 mGal), location accuracy of IGNS was up to reach ~1.0-3.0 n miles in the South China Sea.

  19. High Precision GNSS Guidance for Field Mobile Robots

    Directory of Open Access Journals (Sweden)

    Ladislav Jurišica

    2012-11-01

    Full Text Available In this paper, we discuss GNSS (Global Navigation Satellite System guidance for field mobile robots. Several GNSS systems and receivers, as well as multiple measurement methods and principles of GNSS systems are examined. We focus mainly on sources of errors and investigate diverse approaches for precise measuring and effective use of GNSS systems for real-time robot localization. The main body of the article compares two GNSS receivers and their measurement methods. We design, implement and evaluate several mathematical methods for precise robot localization.

  20. Apollo experience report: Guidance and control systems. Engineering simulation program

    Science.gov (United States)

    Gilbert, D. W.

    1973-01-01

    The Apollo Program experience from early 1962 to July 1969 with respect to the engineering-simulation support and the problems encountered is summarized in this report. Engineering simulation in support of the Apollo guidance and control system is discussed in terms of design analysis and verification, certification of hardware in closed-loop operation, verification of hardware/software compatibility, and verification of both software and procedures for each mission. The magnitude, time, and cost of the engineering simulations are described with respect to hardware availability, NASA and contractor facilities (for verification of the command module, the lunar module, and the primary guidance, navigation, and control system), and scheduling and planning considerations. Recommendations are made regarding implementation of similar, large-scale simulations for future programs.

  1. A simultaneous navigation and radiation evasion algorithm (SNARE)

    Energy Technology Data Exchange (ETDEWEB)

    Khasawneh, Mohammed A., E-mail: mkha@ieee.org [Department of Electrical Engineering, Jordan University of Science and Technology, Irbid 221 10 (Jordan); Jaradat, Mohammad A., E-mail: majaradat@just.edu.jo [Department of Mechanical Engineering, Jordan University of Science and Technology, Irbid 221 10 (Jordan); Al-Shboul, Zeina Aman M., E-mail: xeinaaman@gmail.com [Department of Electrical Engineering, Jordan University of Science and Technology, Irbid 221 10 (Jordan)

    2013-12-15

    Highlights: • A new navigation algorithm for radiation evasion around nuclear facilities. • An optimization criteria minimized under algorithm operation. • A man-borne device guiding the occupational worker towards paths that warrant least radiation × time products. • Benefits of using localized navigation as opposed to global navigation schemas. • A path discrimination function for finding the navigational paths exhibiting the least amounts of radiation. - Abstract: In this paper, we address the issue of localization as pertains to indoor navigation under radiation contaminated environments. In this context, navigation, in the absence of any GPS signals, is guided by the location of the sensors that make up the entire wireless sensor network in a given locality within a nuclear facility. It, also, draws on the radiation levels as measured by the sensors around a given locale. Here, localization is inherently embedded into the algorithm presented in (Khasawneh et al., 2011a, 2011b) which was designed to provide navigational guidance to optimize any of two criteria: “Radiation Evasion” and “Nearest Exit”. As such, the algorithm can either be applied to setting a navigational “lowest” radiation exposure path from an initial point A to some other point B; a case typical of occupational workers performing maintenance operations around the facility; or providing a radiation-safe passage from point A to the nearest exit. Algorithm's navigational performance is tested under statistical reference, wherein for a given number of runs (trials) algorithm performance is evaluated as a function of the number of steps of look-ahead it uses to acquire navigational information, and is compared against the performance of the renowned Dijkstra global navigation algorithm. This is done with reference to the amount of (radiation × time) product and that of the time needed to reach an exit point, under the two optimization criteria. To evaluate algorithm

  2. A simultaneous navigation and radiation evasion algorithm (SNARE)

    International Nuclear Information System (INIS)

    Khasawneh, Mohammed A.; Jaradat, Mohammad A.; Al-Shboul, Zeina Aman M.

    2013-01-01

    Highlights: • A new navigation algorithm for radiation evasion around nuclear facilities. • An optimization criteria minimized under algorithm operation. • A man-borne device guiding the occupational worker towards paths that warrant least radiation × time products. • Benefits of using localized navigation as opposed to global navigation schemas. • A path discrimination function for finding the navigational paths exhibiting the least amounts of radiation. - Abstract: In this paper, we address the issue of localization as pertains to indoor navigation under radiation contaminated environments. In this context, navigation, in the absence of any GPS signals, is guided by the location of the sensors that make up the entire wireless sensor network in a given locality within a nuclear facility. It, also, draws on the radiation levels as measured by the sensors around a given locale. Here, localization is inherently embedded into the algorithm presented in (Khasawneh et al., 2011a, 2011b) which was designed to provide navigational guidance to optimize any of two criteria: “Radiation Evasion” and “Nearest Exit”. As such, the algorithm can either be applied to setting a navigational “lowest” radiation exposure path from an initial point A to some other point B; a case typical of occupational workers performing maintenance operations around the facility; or providing a radiation-safe passage from point A to the nearest exit. Algorithm's navigational performance is tested under statistical reference, wherein for a given number of runs (trials) algorithm performance is evaluated as a function of the number of steps of look-ahead it uses to acquire navigational information, and is compared against the performance of the renowned Dijkstra global navigation algorithm. This is done with reference to the amount of (radiation × time) product and that of the time needed to reach an exit point, under the two optimization criteria. To evaluate algorithm

  3. Technical Note: Mobile accelerator guidance using an optical tracker during docking in IOERT procedures.

    Science.gov (United States)

    Marinetto, Eugenio; Victores, Juan González; García-Sevilla, Mónica; Muñoz, Mercedes; Calvo, Felipe Ángel; Balaguer, Carlos; Desco, Manuel; Pascau, Javier

    2017-10-01

    Intraoperative electron radiation therapy (IOERT) involves the delivery of a high radiation dose during tumor resection in a shorter time than other radiation techniques, thus improving local control of tumors. However, a linear accelerator device is needed to produce the beam safely. Mobile linear accelerators have been designed as dedicated units that can be moved into the operating room and deliver radiation in situ. Correct and safe dose delivery is a key concern when using mobile accelerators. The applicator is commonly fixed to the patient's bed to ensure that the dose is delivered to the prescribed location, and the mobile accelerator is moved to dock the applicator to the radiation beam output (gantry). In a typical clinical set-up, this task is time-consuming because of safety requirements and the limited degree of freedom of the gantry. The objective of this study was to present a navigation solution based on optical tracking for guidance of docking to improve safety and reduce procedure time. We used an optical tracker attached to the mobile linear accelerator to track the prescribed localization of the radiation collimator inside the operating room. Using this information, the integrated navigation system developed computes the movements that the mobile linear accelerator needs to perform to align the applicator and the radiation gantry and warns the physician if docking is unrealizable according to the available degrees of freedom of the mobile linear accelerator. Furthermore, we coded a software application that connects all the necessary functioning elements and provides a user interface for the system calibration and the docking guidance. The system could safeguard against the spatial limitations of the operating room, calculate the optimal arrangement of the accelerator and reduce the docking time in computer simulations and experimental setups. The system could be used to guide docking with any commercial linear accelerator. We believe that the

  4. Orion Optical Navigation Progress Toward Exploration: Mission 1

    Science.gov (United States)

    Holt, Greg N.; D'Souza, Christopher N.; Saley, David

    2018-01-01

    Optical navigation of human spacecraft was proposed on Gemini and implemented successfully on Apollo as a means of autonomously operating the vehicle in the event of lost communication with controllers on Earth. It shares a history with the "method of lunar distances" that was used in the 18th century and gained some notoriety after its use by Captain James Cook during his 1768 Pacific voyage of the HMS Endeavor. The Orion emergency return system utilizing optical navigation has matured in design over the last several years, and is currently undergoing the final implementation and test phase in preparation for Exploration Mission 1 (EM-1) in 2019. The software development is being worked as a Government Furnished Equipment (GFE) project delivered as an application within the Core Flight Software of the Orion camera controller module. The mathematical formulation behind the initial ellipse fit in the image processing is detailed in Christian. The non-linear least squares refinement then follows the technique of Mortari as an estimation process of the planetary limb using the sigmoid function. The Orion optical navigation system uses a body fixed camera, a decision that was driven by mass and mechanism constraints. The general concept of operations involves a 2-hour pass once every 24 hours, with passes specifically placed before all maneuvers to supply accurate navigation information to guidance and targeting. The pass lengths are limited by thermal constraints on the vehicle since the OpNav attitude generally deviates from the thermally stable tail-to-sun attitude maintained during the rest of the orbit coast phase. Calibration is scheduled prior to every pass due to the unknown nature of thermal effects on the lens distortion and the mounting platform deformations between the camera and star trackers. The calibration technique is described in detail by Christian, et al. and simultaneously estimates the Brown-Conrady coefficients and the Star Tracker

  5. Intelligent personal navigator supported by knowledge-based systems for estimating dead reckoning navigation parameters

    Science.gov (United States)

    Moafipoor, Shahram

    Personal navigators (PN) have been studied for about a decade in different fields and applications, such as safety and rescue operations, security and emergency services, and police and military applications. The common goal of all these applications is to provide precise and reliable position, velocity, and heading information of each individual in various environments. In the PN system developed in this dissertation, the underlying assumption is that the system does not require pre-existing infrastructure to enable pedestrian navigation. To facilitate this capability, a multisensor system concept, based on the Global Positioning System (GPS), inertial navigation, barometer, magnetometer, and a human pedometry model has been developed. An important aspect of this design is to use the human body as navigation sensor to facilitate Dead Reckoning (DR) navigation in GPS-challenged environments. The system is designed predominantly for outdoor environments, where occasional loss of GPS lock may happen; however, testing and performance demonstration have been extended to indoor environments. DR navigation is based on a relative-measurement approach, with the key idea of integrating the incremental motion information in the form of step direction (SD) and step length (SL) over time. The foundation of the intelligent navigation system concept proposed here rests in exploiting the human locomotion pattern, as well as change of locomotion in varying environments. In this context, the term intelligent navigation represents the transition from the conventional point-to-point DR to dynamic navigation using the knowledge about the mechanism of the moving person. This approach increasingly relies on integrating knowledge-based systems (KBS) and artificial intelligence (AI) methodologies, including artificial neural networks (ANN) and fuzzy logic (FL). In addition, a general framework of the quality control for the real-time validation of the DR processing is proposed, based on a

  6. 1.5 T augmented reality navigated interventional MRI: paravertebral sympathetic plexus injections.

    Science.gov (United States)

    Marker, David R; U Thainual, Paweena; Ungi, Tamas; Flammang, Aaron J; Fichtinger, Gabor; Iordachita, Iulian I; Carrino, John A; Fritz, Jan

    2017-01-01

    The high contrast resolution and absent ionizing radiation of interventional magnetic resonance imaging (MRI) can be advantageous for paravertebral sympathetic nerve plexus injections. We assessed the feasibility and technical performance of MRI-guided paravertebral sympathetic injections utilizing augmented reality navigation and 1.5 T MRI scanner. A total of 23 bilateral injections of the thoracic (8/23, 35%), lumbar (8/23, 35%), and hypogastric (7/23, 30%) paravertebral sympathetic plexus were prospectively planned in twelve human cadavers using a 1.5 Tesla (T) MRI scanner and augmented reality navigation system. MRI-conditional needles were used. Gadolinium-DTPA-enhanced saline was injected. Outcome variables included the number of control magnetic resonance images, target error of the needle tip, punctures of critical nontarget structures, distribution of the injected fluid, and procedure length. Augmented-reality navigated MRI guidance at 1.5 T provided detailed anatomical visualization for successful targeting of the paravertebral space, needle placement, and perineural paravertebral injections in 46 of 46 targets (100%). A mean of 2 images (range, 1-5 images) were required to control needle placement. Changes of the needle trajectory occurred in 9 of 46 targets (20%) and changes of needle advancement occurred in 6 of 46 targets (13%), which were statistically not related to spinal regions (P = 0.728 and P = 0.86, respectively) and cadaver sizes (P = 0.893 and P = 0.859, respectively). The mean error of the needle tip was 3.9±1.7 mm. There were no punctures of critical nontarget structures. The mean procedure length was 33±12 min. 1.5 T augmented reality-navigated interventional MRI can provide accurate imaging guidance for perineural injections of the thoracic, lumbar, and hypogastric sympathetic plexus.

  7. Optimal Geometric Deployment of a Ground Based Pseudolite Navigation System to Track a Landing Aircraft

    Science.gov (United States)

    2006-06-01

    Machine Guidance Using LocataNet In this pilot study [3], conducted at the BlueScope Steel warehouse in Port Kembla, Australia, the LocataNet system...Study at BlueScope Steel”. Proceedings of the 2004 Annual Meeting of the Institute of Navigation. Dayton, OH, June 2004. 4. Barnes, Joel, Chris

  8. Miniaturized GPS/MEMS IMU integrated board

    Science.gov (United States)

    Lin, Ching-Fang (Inventor)

    2012-01-01

    This invention documents the efforts on the research and development of a miniaturized GPS/MEMS IMU integrated navigation system. A miniaturized GPS/MEMS IMU integrated navigation system is presented; Laser Dynamic Range Imager (LDRI) based alignment algorithm for space applications is discussed. Two navigation cameras are also included to measure the range and range rate which can be integrated into the GPS/MEMS IMU system to enhance the navigation solution.

  9. VISION-AIDED CONTEXT-AWARE FRAMEWORK FOR PERSONAL NAVIGATION SERVICES

    Directory of Open Access Journals (Sweden)

    S. Saeedi

    2012-07-01

    Full Text Available The ubiquity of mobile devices (such as smartphones and tablet-PCs has encouraged the use of location-based services (LBS that are relevant to the current location and context of a mobile user. The main challenge of LBS is to find a pervasive and accurate personal navigation system (PNS in different situations of a mobile user. In this paper, we propose a method of personal navigation for pedestrians that allows a user to freely move in outdoor environments. This system aims at detection of the context information which is useful for improving personal navigation. The context information for a PNS consists of user activity modes (e.g. walking, stationary, driving, and etc. and the mobile device orientation and placement with respect to the user. After detecting the context information, a low-cost integrated positioning algorithm has been employed to estimate pedestrian navigation parameters. The method is based on the integration of the relative user’s motion (changes of velocity and heading angle estimation based on the video image matching and absolute position information provided by GPS. A Kalman filter (KF has been used to improve the navigation solution when the user is walking and the phone is in his/her hand. The Experimental results demonstrate the capabilities of this method for outdoor personal navigation systems.

  10. Bioinspired polarization navigation sensor for autonomous munitions systems

    Science.gov (United States)

    Giakos, G. C.; Quang, T.; Farrahi, T.; Deshpande, A.; Narayan, C.; Shrestha, S.; Li, Y.; Agarwal, M.

    2013-05-01

    Small unmanned aerial vehicles UAVs (SUAVs), micro air vehicles (MAVs), Automated Target Recognition (ATR), and munitions guidance, require extreme operational agility and robustness which can be partially offset by efficient bioinspired imaging sensor designs capable to provide enhanced guidance, navigation and control capabilities (GNC). Bioinspired-based imaging technology can be proved useful either for long-distance surveillance of targets in a cluttered environment, or at close distances limited by space surroundings and obstructions. The purpose of this study is to explore the phenomenology of image formation by different insect eye architectures, which would directly benefit the areas of defense and security, on the following four distinct areas: a) fabrication of the bioinspired sensor b) optical architecture, c) topology, and d) artificial intelligence. The outcome of this study indicates that bioinspired imaging can impact the areas of defense and security significantly by dedicated designs fitting into different combat scenarios and applications.

  11. ATON (Autonomous Terrain-based Optical Navigation) for exploration missions: recent flight test results

    Science.gov (United States)

    Theil, S.; Ammann, N.; Andert, F.; Franz, T.; Krüger, H.; Lehner, H.; Lingenauber, M.; Lüdtke, D.; Maass, B.; Paproth, C.; Wohlfeil, J.

    2018-03-01

    Since 2010 the German Aerospace Center is working on the project Autonomous Terrain-based Optical Navigation (ATON). Its objective is the development of technologies which allow autonomous navigation of spacecraft in orbit around and during landing on celestial bodies like the Moon, planets, asteroids and comets. The project developed different image processing techniques and optical navigation methods as well as sensor data fusion. The setup—which is applicable to many exploration missions—consists of an inertial measurement unit, a laser altimeter, a star tracker and one or multiple navigation cameras. In the past years, several milestones have been achieved. It started with the setup of a simulation environment including the detailed simulation of camera images. This was continued by hardware-in-the-loop tests in the Testbed for Robotic Optical Navigation (TRON) where images were generated by real cameras in a simulated downscaled lunar landing scene. Data were recorded in helicopter flight tests and post-processed in real-time to increase maturity of the algorithms and to optimize the software. Recently, two more milestones have been achieved. In late 2016, the whole navigation system setup was flying on an unmanned helicopter while processing all sensor information onboard in real time. For the latest milestone the navigation system was tested in closed-loop on the unmanned helicopter. For that purpose the ATON navigation system provided the navigation state for the guidance and control of the unmanned helicopter replacing the GPS-based standard navigation system. The paper will give an introduction to the ATON project and its concept. The methods and algorithms of ATON are briefly described. The flight test results of the latest two milestones are presented and discussed.

  12. Using the framework of corporate culture in “mergers” to support the development of a cultural basis for integrative medicine – guidance for building an integrative medicine department or service

    Science.gov (United States)

    Witt, Claudia M; Pérard, Marion; Berman, Brian; Berman, Susan; Birdsall, Timothy C; Defren, Horst; Kümmel, Sherko; Deng, Gary; Dobos, Gustav; Drexler, Atje; Holmberg, Christine; Horneber, Markus; Jütte, Robert; Knutson, Lori; Kummer, Christopher; Volpers, Susanne; Schweiger, David

    2015-01-01

    Background An increasing number of clinics offer complementary or integrative medicine services; however, clear guidance about how complementary medicine could be successfully and efficiently integrated into conventional health care settings is still lacking. Combining conventional and complementary medicine into integrative medicine can be regarded as a kind of merger. In a merger, two or more organizations − usually companies − are combined into one in order to strengthen the companies financially and strategically. The corporate culture of both merger partners has an important influence on the integration. Purpose The aim of this project was to transfer the concept of corporate culture in mergers to the merging of two medical systems. Methods A two-step approach (literature analyses and expert consensus procedure) was used to develop practical guidance for the development of a cultural basis for integrative medicine, based on the framework of corporate culture in “mergers,” which could be used to build an integrative medicine department or integrative medicine service. Results Results include recommendations for general strategic dimensions (definition of the medical model, motivation for integration, clarification of the available resources, development of the integration team, and development of a communication strategy), and recommendations to overcome cultural differences (the clinic environment, the professional language, the professional image, and the implementation of evidence-based medicine). Conclusion The framework of mergers in corporate culture provides an understanding of the difficulties involved in integrative medicine projects. The specific recommendations provide a good basis for more efficient implementation. PMID:25632226

  13. Development of Fast Error Compensation Algorithm for Integrated Inertial-Satellite Navigation System of Small-size Unmanned Aerial Vehicles in Complex Environment

    Directory of Open Access Journals (Sweden)

    A. V. Fomichev

    2015-01-01

    Full Text Available In accordance with the structural features of small-size unmanned aerial vehicle (UAV, and considering the feasibility of this project, the article studies an integrated inertial-satellite navigation system (INS. The INS algorithm development is based on the method of indirect filtration and principle of loosely coupled combination of output data on UAV positions and velocity. Data on position and velocity are provided from the strapdown inertial navigation system (SINS and satellite navigation system (GPS. A difference between the output flows of measuring data on position and velocity provided from the SINS and GPS is used to evaluate SINS errors by means of the basic algorithm of Kalman filtering. Then the outputs of SINS are revised. The INS possesses the following advantages: a simpler mathematical model of Kalman filtering, high reliability, two independently operating navigation systems, and high redundancy of available navigation information.But in case of loosely coupled scheme, INS can meet the challenge of high precision and reliability of navigation only when the SINS and GPS operating conditions are normal all the time. The proposed INS is used with UAV moving in complex environment due to obstacles available, severe natural climatic conditions, etc. This case expects that it is impossible for UAV to receive successful GPS-signals frequently. In order to solve this problem, was developed an algorithm for rapid compensation for errors of INS information, which could effectively solve the problem of failure of the navigation system in case there are no GPS-signals .Since it is almost impossible to obtain the data of the real trajectory in practice, in the course of simulation in accordance with the kinematic model of the UAV and the complex environment of the terrain, the flight path generator is used to produce the flight path. The errors of positions and velocities are considered as an indicator of the INS effectiveness. The results

  14. A Discussion on e-Navigation and Implementation in Turkey

    Directory of Open Access Journals (Sweden)

    Y.V. Aydogdu

    2014-03-01

    Full Text Available Electronic navigation, which has great important for ship management, has taken a step with technological improvements. In the result of these enhancements, new systems appeared as well as existing systems and these systems began to be integrated each other or used data of obtaining from the others like that AIS, Radar, ECDIS etc. All these and likely future systems have been put together under the roof of enhanced navigation (e-navigation is defined by organizations such as International Maritime Organization (IMO, International Association of Marine Aids to Navigation and Lighthouse Authorities (IALA, General Lighthouse Authority (GLA etc. Especially IALA guidelines serve as model future applications in Turkish waterways. In this study aim to redefine e-navigation concept based on maritime safety awareness, maritime service portfolio (MSC 85/26 and discuss possible applications.

  15. Granger causal connectivity dissociates navigation networks that subserve allocentric and egocentric path integration.

    Science.gov (United States)

    Lin, Chin-Teng; Chiu, Te-Cheng; Wang, Yu-Kai; Chuang, Chun-Hsiang; Gramann, Klaus

    2018-01-15

    Studies on spatial navigation demonstrate a significant role of the retrosplenial complex (RSC) in the transformation of egocentric and allocentric information into complementary spatial reference frames (SRFs). The tight anatomical connections of the RSC with a wide range of other cortical regions processing spatial information support its vital role within the human navigation network. To better understand how different areas of the navigational network interact, we investigated the dynamic causal interactions of brain regions involved in solving a virtual navigation task. EEG signals were decomposed by independent component analysis (ICA) and subsequently examined for information flow between clusters of independent components (ICs) using direct short-time directed transfer function (sdDTF). The results revealed information flow between the anterior cingulate cortex and the left prefrontal cortex in the theta (4-7 Hz) frequency band and between the prefrontal, motor, parietal, and occipital cortices as well as the RSC in the alpha (8-13 Hz) frequency band. When participants prefered to use distinct reference frames (egocentric vs. allocentric) during navigation was considered, a dominant occipito-parieto-RSC network was identified in allocentric navigators. These results are in line with the assumption that the RSC, parietal, and occipital cortices are involved in transforming egocentric visual-spatial information into an allocentric reference frame. Moreover, the RSC demonstrated the strongest causal flow during changes in orientation, suggesting that this structure directly provides information on heading changes in humans. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Cloud Absorption Radiometer Autonomous Navigation System - CANS

    Science.gov (United States)

    Kahle, Duncan; Gatebe, Charles; McCune, Bill; Hellwig, Dustan

    2013-01-01

    CAR (cloud absorption radiometer) acquires spatial reference data from host aircraft navigation systems. This poses various problems during CAR data reduction, including navigation data format, accuracy of position data, accuracy of airframe inertial data, and navigation data rate. Incorporating its own navigation system, which included GPS (Global Positioning System), roll axis inertia and rates, and three axis acceleration, CANS expedites data reduction and increases the accuracy of the CAR end data product. CANS provides a self-contained navigation system for the CAR, using inertial reference and GPS positional information. The intent of the software application was to correct the sensor with respect to aircraft roll in real time based upon inputs from a precision navigation sensor. In addition, the navigation information (including GPS position), attitude data, and sensor position details are all streamed to a remote system for recording and later analysis. CANS comprises a commercially available inertial navigation system with integral GPS capability (Attitude Heading Reference System AHRS) integrated into the CAR support structure and data system. The unit is attached to the bottom of the tripod support structure. The related GPS antenna is located on the P-3 radome immediately above the CAR. The AHRS unit provides a RS-232 data stream containing global position and inertial attitude and velocity data to the CAR, which is recorded concurrently with the CAR data. This independence from aircraft navigation input provides for position and inertial state data that accounts for very small changes in aircraft attitude and position, sensed at the CAR location as opposed to aircraft state sensors typically installed close to the aircraft center of gravity. More accurate positional data enables quicker CAR data reduction with better resolution. The CANS software operates in two modes: initialization/calibration and operational. In the initialization/calibration mode

  17. Needle and catheter navigation using electromagnetic tracking for computer-assisted C-arm CT interventions

    Science.gov (United States)

    Nagel, Markus; Hoheisel, Martin; Petzold, Ralf; Kalender, Willi A.; Krause, Ulrich H. W.

    2007-03-01

    Integrated solutions for navigation systems with CT, MR or US systems become more and more popular for medical products. Such solutions improve the medical workflow, reduce hardware, space and costs requirements. The purpose of our project was to develop a new electromagnetic navigation system for interventional radiology which is integrated into C-arm CT systems. The application is focused on minimally invasive percutaneous interventions performed under local anaesthesia. Together with a vacuum-based patient immobilization device and newly developed navigation tools (needles, panels) we developed a safe and fully automatic navigation system. The radiologist can directly start with navigated interventions after loading images without any prior user interaction. The complete system is adapted to the requirements of the radiologist and to the clinical workflow. For evaluation of the navigation system we performed different phantom studies and achieved an average accuracy of better than 2.0 mm.

  18. Exoatmospheric intercepts using zero effort miss steering for midcourse guidance

    Science.gov (United States)

    Newman, Brett

    The suitability of proportional navigation, or an equivalent zero effort miss formulation, for exatmospheric intercepts during midcourse guidance, followed by a ballistic coast to the endgame, is addressed. The problem is formulated in terms of relative motion in a general, three dimensional framework. The proposed guidance law for the commanded thrust vector orientation consists of the sum of two terms: (1) along the line of sight unit direction and (2) along the zero effort miss component perpendicular to the line of sight and proportional to the miss itself and a guidance gain. If the guidance law is to be suitable for longer range targeting applications with significant ballistic coasting after burnout, determination of the zero effort miss must account for the different gravitational accelerations experienced by each vehicle. The proposed miss determination techniques employ approximations for the true differential gravity effect and thus, are less accurate than a direct numerical propagation of the governing equations, but more accurate than a baseline determination, which assumes equal accelerations for both vehicles. Approximations considered are constant, linear, quadratic, and linearized inverse square models. Theoretical results are applied to a numerical engagement scenario and the resulting performance is evaluated in terms of the miss distances determined from nonlinear simulation.

  19. Sperm as microswimmers - navigation and sensing at the physical limit

    Science.gov (United States)

    Kaupp, Ulrich B.; Alvarez, Luis

    2016-11-01

    Many cells and microorganisms have evolved a motility apparatus to explore their surroundings. For guidance, these biological microswimmers rely on physical and chemical cues that are transduced by cellular pathways into directed movement - a process called taxis. Only few biological microswimmers have been studied as detailed as sperm from sea urchins. Sperm and eggs are released into the seawater. To enhance the chances of fertilization, eggs release chemical factors - called chemoattractants - that establish a chemical gradient and, thereby, guide sperm to the egg. Sea urchin sperm constitute a unique model system for understanding cell navigation at every level: from molecules to cell behaviours. We will outline the chemotactic signalling pathway of sperm from the sea urchin Arbacia punctulata and discuss how signalling controls navigation in a chemical gradient. Finally, we discuss recent insights into sperm chemotaxis in three dimensions (3D).

  20. A BLE-Based Pedestrian Navigation System for Car Searching in Indoor Parking Garages.

    Science.gov (United States)

    Wang, Sheng-Shih

    2018-05-05

    The continuous global increase in the number of cars has led to an increase in parking issues, particularly with respect to the search for available parking spaces and finding cars. In this paper, we propose a navigation system for car owners to find their cars in indoor parking garages. The proposed system comprises a car-searching mobile app and a positioning-assisting subsystem. The app guides car owners to their cars based on a “turn-by-turn” navigation strategy, and has the ability to correct the user’s heading orientation. The subsystem uses beacon technology for indoor positioning, supporting self-guidance of the car-searching mobile app. This study also designed a local coordinate system to support the identification of the locations of parking spaces and beacon devices. We used Android as the platform to implement the proposed car-searching mobile app, and used Bytereal HiBeacon devices to implement the proposed positioning-assisting subsystem. We also deployed the system in a parking lot in our campus for testing. The experimental results verified that the proposed system not only works well, but also provides the car owner with the correct route guidance information.

  1. Robust approximate optimal guidance strategies for aeroassisted orbital transfer missions

    Science.gov (United States)

    Ilgen, Marc R.

    This thesis presents the application of game theoretic and regular perturbation methods to the problem of determining robust approximate optimal guidance laws for aeroassisted orbital transfer missions with atmospheric density and navigated state uncertainties. The optimal guidance problem is reformulated as a differential game problem with the guidance law designer and Nature as opposing players. The resulting equations comprise the necessary conditions for the optimal closed loop guidance strategy in the presence of worst case parameter variations. While these equations are nonlinear and cannot be solved analytically, the presence of a small parameter in the equations of motion allows the method of regular perturbations to be used to solve the equations approximately. This thesis is divided into five parts. The first part introduces the class of problems to be considered and presents results of previous research. The second part then presents explicit semianalytical guidance law techniques for the aerodynamically dominated region of flight. These guidance techniques are applied to unconstrained and control constrained aeroassisted plane change missions and Mars aerocapture missions, all subject to significant atmospheric density variations. The third part presents a guidance technique for aeroassisted orbital transfer problems in the gravitationally dominated region of flight. Regular perturbations are used to design an implicit guidance technique similar to the second variation technique but that removes the need for numerically computing an optimal trajectory prior to flight. This methodology is then applied to a set of aeroassisted inclination change missions. In the fourth part, the explicit regular perturbation solution technique is extended to include the class of guidance laws with partial state information. This methodology is then applied to an aeroassisted plane change mission using inertial measurements and subject to uncertainties in the initial value

  2. The Navigation Guide—Evidence-Based Medicine Meets Environmental Health: Integration of Animal and Human Evidence for PFOA Effects on Fetal Growth

    Science.gov (United States)

    Koustas, Erica; Sutton, Patrice; Johnson, Paula I.; Atchley, Dylan S.; Sen, Saunak; Robinson, Karen A.; Axelrad, Daniel A.; Woodruff, Tracey J.

    2014-01-01

    Background: The Navigation Guide is a novel systematic review method to synthesize scientific evidence and reach strength of evidence conclusions for environmental health decision making. Objective: Our aim was to integrate scientific findings from human and nonhuman studies to determine the overall strength of evidence for the question “Does developmental exposure to perfluorooctanoic acid (PFOA) affect fetal growth in humans?” Methods: We developed and applied prespecified criteria to systematically and transparently a) rate the quality of the scientific evidence as “high,” “moderate,” or “low”; b) rate the strength of the human and nonhuman evidence separately as “sufficient,” “limited,” “moderate,” or “evidence of lack of toxicity”; and c) integrate the strength of the human and nonhuman evidence ratings into a strength of the evidence conclusion. Results: We identified 18 epidemiology studies and 21 animal toxicology studies relevant to our study question. We rated both the human and nonhuman mammalian evidence as “moderate” quality and “sufficient” strength. Integration of these evidence ratings produced a final strength of evidence rating in which review authors concluded that PFOA is “known to be toxic” to human reproduction and development based on sufficient evidence of decreased fetal growth in both human and nonhuman mammalian species. Conclusion: We concluded that developmental exposure to PFOA adversely affects human health based on sufficient evidence of decreased fetal growth in both human and nonhuman mammalian species. The results of this case study demonstrate the application of a systematic and transparent methodology, via the Navigation Guide, for reaching strength of evidence conclusions in environmental health. Citation: Lam J, Koustas E, Sutton P, Johnson PI, Atchley DS, Sen S, Robinson KA, Axelrad DA, Woodruff TJ. 2014. The Navigation Guide—evidence-based medicine meets environmental health

  3. Clinical Application of Different Surgical Navigation Systems in Complex Craniomaxillofacial Surgery: The Use of Multisurface 3-Dimensional Images and a 2-Plane Reference System.

    Science.gov (United States)

    Liu, Tom J; Ko, An-Ta; Tang, Yueh-Bih; Lai, Hong-Shiee; Chien, Hsiung-Fei; Hsieh, Thomas Mon-Hsian

    2016-04-01

    Intraoperative navigation is a tool that provides surgeons with real-time guidance based on patients' preoperative imaging studies. The application of intraoperative navigation to neurosurgery and otolaryngology has been well documented; however, only isolated reports have analyzed its potential in the field of craniomaxillofacial surgery. From November 2010 to July 2014, 15 patients were operated on for complex craniomaxillofacial surgery with assistance by 3 different navigation systems, which used either infrared or electromagnetic technologies. We imported fine-cut (0.625-mm) computed tomographic scan images of the patients to the navigation systems whose software processed them into multisurface 3-dimentional models used as guiding material for the surgical navigation. We also developed a simple "2-plane reference system" to ensure that the final results were symmetric to the normal half of the face. Appearance outcome was evaluated by questionnaire. Of these 15 cases, 3 cases were performed with infrared-based navigation, and the remaining 12 cases were accomplished by electromagnetic technology. Most of these cases resulted in satisfactory outcomes after tumor resection, posttraumatic reconstruction, and postablative reconstruction. Navigation systems offer highly valuable intraoperative assistance in complex craniomaxillofacial surgery. Not only can these systems pinpoint deep-seated lesions as neurosurgeons or otolaryngologists do, but they can also use a simple 2-plane reference system for accurate bone alignment. Moreover, advancements in multisurface 3-D models provide us more reliable intuitive image guidance. The application of electromagnetic technology, with its smaller reference obviation of the line-of-sight problem, makes the manipulation of craniomaxillofacial surgery more comfortable.

  4. Systems Engineering Approach to Develop Guidance, Navigation and Control Algorithms for Unmanned Ground Vehicle

    Science.gov (United States)

    2016-09-01

    Global Positioning System HNA hybrid navigation algorithm HRI human-robot interface IED Improvised Explosive Device IMU inertial measurement unit...Potential Field Method R&D research and development RDT&E Research, development, test and evaluation RF radiofrequency RGB red, green and blue ROE...were radiofrequency (RF) controlled and pneumatically actuated upon receiving the wireless commands from the radio operator. The pairing of such an

  5. Towards Safe Navigation by Formalizing Navigation Rules

    Directory of Open Access Journals (Sweden)

    Arne Kreutzmann

    2013-06-01

    Full Text Available One crucial aspect of safe navigation is to obey all navigation regulations applicable, in particular the collision regulations issued by the International Maritime Organization (IMO Colregs. Therefore, decision support systems for navigation need to respect Colregs and this feature should be verifiably correct. We tackle compliancy of navigation regulations from a perspective of software verification. One common approach is to use formal logic, but it requires to bridge a wide gap between navigation concepts and simple logic. We introduce a novel domain specification language based on a spatio-temporal logic that allows us to overcome this gap. We are able to capture complex navigation concepts in an easily comprehensible representation that can direcly be utilized by various bridge systems and that allows for software verification.

  6. Low Cost Multisensor Kinematic Positioning and Navigation System with Linux/RTAI

    Directory of Open Access Journals (Sweden)

    Baoxin Hu

    2012-09-01

    Full Text Available Despite its popularity, the development of an embedded real-time multisensor kinematic positioning and navigation system discourages many researchers and developers due to its complicated hardware environment setup and time consuming device driver development. To address these issues, this paper proposed a multisensor kinematic positioning and navigation system built on Linux with Real Time Application Interface (RTAI, which can be constructed in a fast and economical manner upon popular hardware platforms. The authors designed, developed, evaluated and validated the application of Linux/RTAI in the proposed system for the integration of the low cost MEMS IMU and OEM GPS sensors. The developed system with Linux/RTAI as the core of a direct geo-referencing system provides not only an excellent hard real-time performance but also the conveniences for sensor hardware integration and real-time software development. A software framework is proposed in this paper for a universal kinematic positioning and navigation system with loosely-coupled integration architecture. In addition, general strategies of sensor time synchronization in a multisensor system are also discussed. The success of the loosely-coupled GPS-aided inertial navigation Kalman filter is represented via post-processed solutions from road tests.

  7. A Route Guidance System for Car Finding in Indoor Parking Garages

    OpenAIRE

    Pei-Chun Lee; Sheng-Shih Wang

    2016-01-01

    This paper presents a route guidance system for car owners to find their cars in parking garages. The presents system comprises a positioning-assisting subsystem and a car-finding mobile app. The positioning-assisting subsystem mainly uses the iBeacon technology for indoor positioning. The car-finding mobile app guides car owners to their cars based on a non-map navigation strategy. This study also designs a virtual coordinate system to support identifying the locations of parking spaces and ...

  8. Navigating neurites utilize cellular topography of Schwann cell somas and processes for optimal guidance

    Science.gov (United States)

    Lopez-Fagundo, Cristina; Mitchel, Jennifer A.; Ramchal, Talisha D.; Dingle, Yu-Ting L.; Hoffman-Kim, Diane

    2013-01-01

    The path created by aligned Schwann cells (SCs) after nerve injury underlies peripheral nerve regeneration. We developed geometric bioinspired substrates to extract key information needed for axon guidance by deconstructing the topographical cues presented by SCs. We have previously reported materials that directly replicate SC topography with micro- and nanoscale resolution, but a detailed explanation of the means of directed axon extension on SC topography has not yet been described. Here, using neurite tracing and time-lapse microscopy, we analyzed the SC features that influence axon guidance. Novel poly(dimethylsiloxane) materials, fabricated via photolithography, incorporated bioinspired topographical components with the shapes and sizes of aligned SCs, namely somas and processes, where the length of the processes were varied but the soma geometry and dimensions were kept constant. Rat dorsal root ganglia neurites aligned to all materials presenting bioinspired topography after a 5 days in culture and to bioinspired materials presenting soma and process features after only 17 hours in culture. Key findings of this study were: Neurite response to underlying bioinspired topographical features was time dependent, where at 5 days, neurites aligned most strongly to materials presenting combinations of soma and process features, with higher than average density of either process or soma features; but at 17 hours they aligned more strongly to materials presenting average densities of soma and process features and to materials presenting process features only. These studies elucidate the influence of SC topography on axon guidance in a time-dependent setting and have implications for the optimization of nerve regeneration strategies. PMID:23557939

  9. An Imaging Sensor-Aided Vision Navigation Approach that Uses a Geo-Referenced Image Database.

    Science.gov (United States)

    Li, Yan; Hu, Qingwu; Wu, Meng; Gao, Yang

    2016-01-28

    In determining position and attitude, vision navigation via real-time image processing of data collected from imaging sensors is advanced without a high-performance global positioning system (GPS) and an inertial measurement unit (IMU). Vision navigation is widely used in indoor navigation, far space navigation, and multiple sensor-integrated mobile mapping. This paper proposes a novel vision navigation approach aided by imaging sensors and that uses a high-accuracy geo-referenced image database (GRID) for high-precision navigation of multiple sensor platforms in environments with poor GPS. First, the framework of GRID-aided vision navigation is developed with sequence images from land-based mobile mapping systems that integrate multiple sensors. Second, a highly efficient GRID storage management model is established based on the linear index of a road segment for fast image searches and retrieval. Third, a robust image matching algorithm is presented to search and match a real-time image with the GRID. Subsequently, the image matched with the real-time scene is considered to calculate the 3D navigation parameter of multiple sensor platforms. Experimental results show that the proposed approach retrieves images efficiently and has navigation accuracies of 1.2 m in a plane and 1.8 m in height under GPS loss in 5 min and within 1500 m.

  10. Visual navigation using edge curve matching for pinpoint planetary landing

    Science.gov (United States)

    Cui, Pingyuan; Gao, Xizhen; Zhu, Shengying; Shao, Wei

    2018-05-01

    Pinpoint landing is challenging for future Mars and asteroid exploration missions. Vision-based navigation scheme based on feature detection and matching is practical and can achieve the required precision. However, existing algorithms are computationally prohibitive and utilize poor-performance measurements, which pose great challenges for the application of visual navigation. This paper proposes an innovative visual navigation scheme using crater edge curves during descent and landing phase. In the algorithm, the edge curves of the craters tracked from two sequential images are utilized to determine the relative attitude and position of the lander through a normalized method. Then, considering error accumulation of relative navigation, a method is developed. That is to integrate the crater-based relative navigation method with crater-based absolute navigation method that identifies craters using a georeferenced database for continuous estimation of absolute states. In addition, expressions of the relative state estimate bias are derived. Novel necessary and sufficient observability criteria based on error analysis are provided to improve the navigation performance, which hold true for similar navigation systems. Simulation results demonstrate the effectiveness and high accuracy of the proposed navigation method.

  11. Error Analysis System for Spacecraft Navigation Using the Global Positioning System (GPS)

    Science.gov (United States)

    Truong, S. H.; Hart, R. C.; Hartman, K. R.; Tomcsik, T. L.; Searl, J. E.; Bernstein, A.

    1997-01-01

    The Flight Dynamics Division (FDD) at the National Aeronautics and Space Administration (NASA) Goddard Space Flight Center (GSFC) is currently developing improved space-navigation filtering algorithms to use the Global Positioning System (GPS) for autonomous real-time onboard orbit determination. In connection with a GPS technology demonstration on the Small Satellite Technology Initiative (SSTI)/Lewis spacecraft, FDD analysts and programmers have teamed with the GSFC Guidance, Navigation, and Control Branch to develop the GPS Enhanced Orbit Determination Experiment (GEODE) system. The GEODE system consists of a Kalman filter operating as a navigation tool for estimating the position, velocity, and additional states required to accurately navigate the orbiting Lewis spacecraft by using astrodynamic modeling and GPS measurements from the receiver. A parallel effort at the FDD is the development of a GPS Error Analysis System (GEAS) that will be used to analyze and improve navigation filtering algorithms during development phases and during in-flight calibration. For GEAS, the Kalman filter theory is extended to estimate the errors in position, velocity, and other error states of interest. The estimation of errors in physical variables at regular intervals will allow the time, cause, and effect of navigation system weaknesses to be identified. In addition, by modeling a sufficient set of navigation system errors, a system failure that causes an observed error anomaly can be traced and accounted for. The GEAS software is formulated using Object Oriented Design (OOD) techniques implemented in the C++ programming language on a Sun SPARC workstation. The Phase 1 of this effort is the development of a basic system to be used to evaluate navigation algorithms implemented in the GEODE system. This paper presents the GEAS mathematical methodology, systems and operations concepts, and software design and implementation. Results from the use of the basic system to evaluate

  12. A Novel 3D Multilateration Sensor Using Distributed Ultrasonic Beacons for Indoor Navigation

    Directory of Open Access Journals (Sweden)

    Rohan Kapoor

    2016-10-01

    Full Text Available Navigation and guidance systems are a critical part of any autonomous vehicle. In this paper, a novel sensor grid using 40 KHz ultrasonic transmitters is presented for adoption in indoor 3D positioning applications. In the proposed technique, a vehicle measures the arrival time of incoming ultrasonic signals and calculates the position without broadcasting to the grid. This system allows for conducting silent or covert operations and can also be used for the simultaneous navigation of a large number of vehicles. The transmitters and receivers employed are first described. Transmission lobe patterns and receiver directionality determine the geometry of transmitter clusters. Range and accuracy of measurements dictate the number of sensors required to navigate in a given volume. Laboratory experiments were performed in which a small array of transmitters was set up and the sensor system was tested for position accuracy. The prototype system is shown to have a 1-sigma position error of about 16 cm, with errors between 7 and 11 cm in the local horizontal coordinates. This research work provides foundations for the future development of ultrasonic navigation sensors for a variety of autonomous vehicle applications.

  13. SLS Navigation Model-Based Design Approach

    Science.gov (United States)

    Oliver, T. Emerson; Anzalone, Evan; Geohagan, Kevin; Bernard, Bill; Park, Thomas

    2018-01-01

    The SLS Program chose to implement a Model-based Design and Model-based Requirements approach for managing component design information and system requirements. This approach differs from previous large-scale design efforts at Marshall Space Flight Center where design documentation alone conveyed information required for vehicle design and analysis and where extensive requirements sets were used to scope and constrain the design. The SLS Navigation Team has been responsible for the Program-controlled Design Math Models (DMMs) which describe and represent the performance of the Inertial Navigation System (INS) and the Rate Gyro Assemblies (RGAs) used by Guidance, Navigation, and Controls (GN&C). The SLS Navigation Team is also responsible for the navigation algorithms. The navigation algorithms are delivered for implementation on the flight hardware as a DMM. For the SLS Block 1-B design, the additional GPS Receiver hardware is managed as a DMM at the vehicle design level. This paper provides a discussion of the processes and methods used to engineer, design, and coordinate engineering trades and performance assessments using SLS practices as applied to the GN&C system, with a particular focus on the Navigation components. These include composing system requirements, requirements verification, model development, model verification and validation, and modeling and analysis approaches. The Model-based Design and Requirements approach does not reduce the effort associated with the design process versus previous processes used at Marshall Space Flight Center. Instead, the approach takes advantage of overlap between the requirements development and management process, and the design and analysis process by efficiently combining the control (i.e. the requirement) and the design mechanisms. The design mechanism is the representation of the component behavior and performance in design and analysis tools. The focus in the early design process shifts from the development and

  14. Surgical navigation with QR codes

    Directory of Open Access Journals (Sweden)

    Katanacho Manuel

    2016-09-01

    Full Text Available The presented work is an alternative to established measurement systems in surgical navigation. The system is based on camera based tracking of QR code markers. The application uses a single video camera, integrated in a surgical lamp, that captures the QR markers attached to surgical instruments and to the patient.

  15. SLS Block 1-B and Exploration Upper Stage Navigation System Design

    Science.gov (United States)

    Oliver, T. Emerson; Park, Thomas B.; Smith, Austin; Anzalone, Evan; Bernard, Bill; Strickland, Dennis; Geohagan, Kevin; Green, Melissa; Leggett, Jarred

    2018-01-01

    The SLS Block 1B vehicle is planned to extend NASA's heavy lift capability beyond the initial SLS Block 1 vehicle. The most noticeable change for this vehicle from SLS Block 1 is the swapping of the upper stage from the Interim Cryogenic Propulsion stage (ICPS), a modified Delta IV upper stage, to the more capable Exploration Upper Stage (EUS). As the vehicle evolves to provide greater lift capability and execute more demanding missions so must the SLS Integrated Navigation System to support those missions. The SLS Block 1 vehicle carries two independent navigation systems. The responsibility of the two systems is delineated between ascent and upper stage flight. The Block 1 navigation system is responsible for the phase of flight between the launch pad and insertion into Low-Earth Orbit (LEO). The upper stage system assumes the mission from LEO to payload separation. For the Block 1B vehicle, the two functions are combined into a single system intended to navigate from ground to payload insertion. Both are responsible for self-disposal once payload delivery is achieved. The evolution of the navigation hardware and algorithms from an inertial-only navigation system for Block 1 ascent flight to a tightly coupled GPS-aided inertial navigation system for Block 1-B is described. The Block 1 GN&C system has been designed to meet a LEO insertion target with a specified accuracy. The Block 1-B vehicle navigation system is designed to support the Block 1 LEO target accuracy as well as trans-lunar or trans-planetary injection accuracy. This is measured in terms of payload impact and stage disposal requirements. Additionally, the Block 1-B vehicle is designed to support human exploration and thus is designed to minimize the probability of Loss of Crew (LOC) through high-quality inertial instruments and Fault Detection, Isolation, and Recovery (FDIR) logic. The preliminary Block 1B integrated navigation system design is presented along with the challenges associated with

  16. Intraluminal laser atherectomy with ultrasound and electromagnetic guidance

    Science.gov (United States)

    Gregory, Kenton W.; Aretz, H. Thomas; Martinelli, Michael A.; LeDet, Earl G.; Hatch, G. F.; Gregg, Richard E.; Sedlacek, Tomas; Haase, Wayne C.

    1991-05-01

    The MagellanTM coronary laser atherectomy system is described. It uses high- resolution ultrasound imaging and electromagnetic sensing to provide real-time guidance and control of laser therapy in the coronary arteries. The system consists of a flexible catheter, an electromagnetic navigation antenna, a sensor signal processor and a computer for image processing and display. The small, flexible catheter combines an ultrasound transducer and laser delivery optics, aimed at the artery wall, and an electromagnetic receiving sensor. An extra-corporeal electromagnetic transmit antenna, in combination with catheter sensors, locates the position of the ultrasound and laser beams in the artery. Navigation and ultrasound data are processed electronically to produce real-time, transverse, and axial cross-section images of the artery wall at selected locations. By exploiting the ability of ultrasound to image beneath the surface of artery walls, it is possible to identify candidate treatment sites and perform safe radial laser debulking of atherosclerotic plaque with reduced danger of perforation. The utility of the system in plaque identification and ablation is demonstrated with imaging and experimental results.

  17. Autonomous aerial vehicles : guidance, control, signal and image processing platform

    International Nuclear Information System (INIS)

    Al-Jarrah, M.; Adiansyah, S.; Marji, Z. M.; Chowdhury, M. S.

    2011-01-01

    The use of unmanned systems is gaining momentum in civil applications after successful use by the armed forces around the globe. Autonomous aerial vehicles are important for providing assistance in monitoring highways, power grid lines, borders, and surveillance of critical infrastructures. It is envisioned that cargo shipping will be completely handled by UAVs by the 2025. Civil use of unmanned autonomous systems brings serious challenges. The need for cost effectiveness, reliability, operation simplicity, safety, and cooperation with human and with other agents are among these challenges. Aerial vehicles operating in the civilian aerospace is the ultimate goal which requires these systems to achieve the reliability of manned aircraft while maintaining their cost effectiveness. In this presentation the development of an autonomous fixed and rotary wing aerial vehicle will be discussed. The architecture of the system from the mission requirements to low level auto pilot control laws will be discussed. Trajectory tracking and path following guidance and control algorithms commonly used and their implementation using of the shelf low cost components will be presented. Autonomous takeo? landing is a key feature that was implemented onboard the vehicle to complete its degree of autonomy. This is implemented based on accurate air-data system designed and fused with sonar measurements, INS/GPS measurements, and vector field method guidance laws. The outcomes of the proposed research is that the AUS-UAV platform named MAZARI is capable of autonomous takeoff and landing based on a pre scheduled flight path using way point navigation and sensor fusion of the inertial navigation system (INS) and global positioning system (GPS). Several technologies need to be mastered when developing a UAV. The navigation task and the need to fuse sensory information to estimate the location of the vehicle is critical to successful autonomous vehicle. Currently extended Kalman filtering is

  18. Development of Integrative STEM Curriculum: A Multiple Case Study of Multi-Disciplinary Teams in Two Pennsylvania High Schools

    Science.gov (United States)

    Rider-Bertrand, Joey H.

    At the start of the 21st century, STEM education was a new priority in many schools as the focus shifted from separate disciplines to integrative STEM education. Unfortunately, there was limited research to offer guidance to practitioners (Brown, 2012; Honey, Pearson & Schweingruber, 2014). This qualitative, multiple case study explored the experiences of two multi-disciplinary teams of secondary teachers from Pennsylvania who developed and implemented integrative STEM curriculum. Four teachers from a rural high school and four teachers from a suburban high school participated in the study. A document review of integrative STEM curriculum and semi-structured interviews were conducted to learn about the curriculum development process and teachers' perceptions regarding conditions that support or hinder success. Individual and cross-case analyses were performed to establish findings and themes. Although the individual case themes varied slightly, the cross-case themes and assertions that emerged provided highly sought after guidance to practitioners and added to the limited body of research on integrative STEM education. This study found that current curriculum models do not fit integrative STEM curriculum, the development process is fluid, and substantial administrative support and resources are necessary to develop, implement, and sustain integrative STEM education programs. The results offered implications for all educators, as well as two examples of how teachers navigated the terrain of integrative STEM curriculum.

  19. Autocommander: A Supervisory Controller for Integrated Guidance and Control for the 2nd Generation Reusable Launch Vehicle

    Science.gov (United States)

    Fisher, J. E.; Lawrence, D. A.; Zhu, J. J.; Jackson, Scott (Technical Monitor)

    2002-01-01

    This paper presents a hierarchical architecture for integrated guidance and control that achieves risk and cost reduction for NASA's 2d generation reusable launch vehicle (RLV). Guidance, attitude control, and control allocation subsystems that heretofore operated independently will now work cooperatively under the coordination of a top-level autocommander. In addition to delivering improved performance from a flight mechanics perspective, the autocommander is intended to provide an autonomous supervisory control capability for traditional mission management under nominal conditions, G&C reconfiguration in response to effector saturation, and abort mode decision-making upon vehicle malfunction. This high-level functionality is to be implemented through the development of a relational database that is populated with the broad range of vehicle and mission specific data and translated into a discrete event system model for analysis, simulation, and onboard implementation. A Stateflow Autocoder software tool that translates the database into the Stateflow component of a Matlab/Simulink simulation is also presented.

  20. Computer-assisted surgery: virtual- and augmented-reality displays for navigation during urological interventions.

    Science.gov (United States)

    van Oosterom, Matthias N; van der Poel, Henk G; Navab, Nassir; van de Velde, Cornelis J H; van Leeuwen, Fijs W B

    2018-03-01

    To provide an overview of the developments made for virtual- and augmented-reality navigation procedures in urological interventions/surgery. Navigation efforts have demonstrated potential in the field of urology by supporting guidance for various disorders. The navigation approaches differ between the individual indications, but seem interchangeable to a certain extent. An increasing number of pre- and intra-operative imaging modalities has been used to create detailed surgical roadmaps, namely: (cone-beam) computed tomography, MRI, ultrasound, and single-photon emission computed tomography. Registration of these surgical roadmaps with the real-life surgical view has occurred in different forms (e.g. electromagnetic, mechanical, vision, or near-infrared optical-based), whereby the combination of approaches was suggested to provide superior outcome. Soft-tissue deformations demand the use of confirmatory interventional (imaging) modalities. This has resulted in the introduction of new intraoperative modalities such as drop-in US, transurethral US, (drop-in) gamma probes and fluorescence cameras. These noninvasive modalities provide an alternative to invasive technologies that expose the patients to X-ray doses. Whereas some reports have indicated navigation setups provide equal or better results than conventional approaches, most trials have been performed in relatively small patient groups and clear follow-up data are missing. The reported computer-assisted surgery research concepts provide a glimpse in to the future application of navigation technologies in the field of urology.

  1. Development and Validation of a Controlled Virtual Environment for Guidance, Navigation and Control of Quadrotor UAV

    Science.gov (United States)

    2013-09-01

    Width Modulation QuarC Quanser Real-time Control RC Remote Controlled RPV Remotely Piloted Vehicles SLAM Simultaneous Localization and Mapping UAV...development of the following systems: 1. Navigation (GPS, Lidar , etc.) 2. Communication (Datalink) 3. Ground Control Station (GUI, software programming

  2. Navigating trade-offs in land-use planning: integrating human well-being into objective setting

    Directory of Open Access Journals (Sweden)

    Vanessa M. Adams

    2014-12-01

    Full Text Available There is an increasing demand for development of natural resources, which can be accompanied by environmental degradation. Planning for multiple land uses requires navigating trade-offs between social, economic, and environmental outcomes arising from different possible futures. To explore these trade-offs, we use the Daly River catchment, in Australia's Northern Territory, as a case study. The catchment contains areas of priority for both conservation and development. In response to the challenge of navigating the required trade-offs, the Daly River Management Advisory Committee (DRMAC initiated a land-use plan for the region. Both development and conservation of natural resources in the catchment will affect human well-being and the long-term provisioning of ecosystem services in diverse ways. To understand some of these impacts, an innovative engagement process was designed to elicit the relative importance of key factors to residents' well-being. The process identified 19 well-being factors grouped into four domains: biodiversity, socio-cultural, recreational, and commercial. Overall, the highest-ranked well-being factors were in the social-cultural and biodiversity domains while commercial values were ranked the least important. Respondents reported low satisfaction with commercial factors as well, noting concerns over environmental impacts from existing developments and sustainability of future developments. We identified differences in the reported importance values for several types of stakeholders, most notably between indigenous respondents and those employed in the agricultural sectors. Indigenous respondents placed greater importance on biodiversity and socio-cultural factors. Agricultural respondents placed greater importance on commercial factors. The outcomes of our engagement were integrated into DRMAC's process of objective-setting to ensure that objectives for each domain were included in land-use planning. Our results can also

  3. Solar Dynamics Observatory Guidance, Navigation, and Control System Overview

    Science.gov (United States)

    Morgenstern, Wendy M.; Bourkland, Kristin L.; Hsu, Oscar C.; Liu, Kuo-Chia; Mason, Paul A. C.; O'Donnell, James R., Jr.; Russo, Angela M.; Starin, Scott R.; Vess, Melissa F.

    2011-01-01

    The Solar Dynamics Observatory (SDO) was designed and built at the Goddard Space Flight Center, launched from Cape Canaveral on February 11, 2010, and reached its final geosynchronous science orbit on March 16, 2010. The purpose of SDO is to observe the Sun and continuously relay data to a dedicated ground station. SDO remains Sun-pointing throughout most of its mission for the instruments to take measurements of the Sun. The SDO attitude control system (ACS) is a single-fault tolerant design. Its fully redundant attitude sensor complement includes sixteen coarse Sun sensors (CSSs), a digital Sun sensor (DSS), three two-axis inertial reference units (IRUs), and two star trackers (STs). The ACS also makes use of the four guide telescopes included as a part of one of the science instruments. Attitude actuation is performed using four reaction wheels assemblies (RWAs) and eight thrusters, with a single main engine used to provide velocity-change thrust for orbit raising. The attitude control software has five nominal control modes, three wheel-based modes and two thruster-based modes. A wheel-based Safehold running in the attitude control electronics box improves the robustness of the system as a whole. All six modes are designed on the same basic proportional-integral-derivative attitude error structure, with more robust modes setting their integral gains to zero. This paper details the final overall design of the SDO guidance, navigation, and control (GN&C) system and how it was used in practice during SDO launch, commissioning, and nominal operations. This overview will include the ACS control modes, attitude determination and sensor calibration, the high gain antenna (HGA) calibration, and jitter mitigation operation. The Solar Dynamics Observatory mission is part of the NASA Living With a Star program, which seeks to understand the changing Sun and its effects on the Solar System, life, and society. To this end, the SDO spacecraft carries three Sun

  4. Shape Perception and Navigation in Blind Adults

    Science.gov (United States)

    Gori, Monica; Cappagli, Giulia; Baud-Bovy, Gabriel; Finocchietti, Sara

    2017-01-01

    Different sensory systems interact to generate a representation of space and to navigate. Vision plays a critical role in the representation of space development. During navigation, vision is integrated with auditory and mobility cues. In blind individuals, visual experience is not available and navigation therefore lacks this important sensory signal. In blind individuals, compensatory mechanisms can be adopted to improve spatial and navigation skills. On the other hand, the limitations of these compensatory mechanisms are not completely clear. Both enhanced and impaired reliance on auditory cues in blind individuals have been reported. Here, we develop a new paradigm to test both auditory perception and navigation skills in blind and sighted individuals and to investigate the effect that visual experience has on the ability to reproduce simple and complex paths. During the navigation task, early blind, late blind and sighted individuals were required first to listen to an audio shape and then to recognize and reproduce it by walking. After each audio shape was presented, a static sound was played and the participants were asked to reach it. Movements were recorded with a motion tracking system. Our results show three main impairments specific to early blind individuals. The first is the tendency to compress the shapes reproduced during navigation. The second is the difficulty to recognize complex audio stimuli, and finally, the third is the difficulty in reproducing the desired shape: early blind participants occasionally reported perceiving a square but they actually reproduced a circle during the navigation task. We discuss these results in terms of compromised spatial reference frames due to lack of visual input during the early period of development. PMID:28144226

  5. Independent Navigation System for a Surgical Colonoscope

    Directory of Open Access Journals (Sweden)

    Lilia A. Ochoa-Luna

    2013-08-01

    Full Text Available This paper provides a novel algorithm to attain the independent navigation of a colonoscopy surgical endoscope. First, it introduces a brief description of this issue through the scientist advance for medical robotics. It then makes a quickly count of the existent methods and at the end it provides the basis in order to propose a new alternative solution with help from vision-guidance. That means that images will be processed and interpreted with the purpose of maintaining the endoscope always at the intestine center. All this considered will help us to reduce colonoscopy surgeries consequences and the most important advantage of this new method proposed is that surgeons will accomplish their work easier and more efficiently.

  6. Smartphone Video Guidance Sensor for Small Satellites

    Data.gov (United States)

    National Aeronautics and Space Administration — Smartphone Video Guidance Sensor(SVGS) for Small Satellites will provide a low-cost,integrated rendezvous & proximity operations sensor system to allow an...

  7. Design and testing of a multi-sensor pedestrian location and navigation platform.

    Science.gov (United States)

    Morrison, Aiden; Renaudin, Valérie; Bancroft, Jared B; Lachapelle, Gérard

    2012-01-01

    Navigation and location technologies are continually advancing, allowing ever higher accuracies and operation under ever more challenging conditions. The development of such technologies requires the rapid evaluation of a large number of sensors and related utilization strategies. The integration of Global Navigation Satellite Systems (GNSSs) such as the Global Positioning System (GPS) with accelerometers, gyros, barometers, magnetometers and other sensors is allowing for novel applications, but is hindered by the difficulties to test and compare integrated solutions using multiple sensor sets. In order to achieve compatibility and flexibility in terms of multiple sensors, an advanced adaptable platform is required. This paper describes the design and testing of the NavCube, a multi-sensor navigation, location and timing platform. The system provides a research tool for pedestrian navigation, location and body motion analysis in an unobtrusive form factor that enables in situ data collections with minimal gait and posture impact. Testing and examples of applications of the NavCube are provided.

  8. Integration of intraoperative stereovision imaging for brain shift visualization during image-guided cranial procedures

    Science.gov (United States)

    Schaewe, Timothy J.; Fan, Xiaoyao; Ji, Songbai; Roberts, David W.; Paulsen, Keith D.; Simon, David A.

    2014-03-01

    Dartmouth and Medtronic Navigation have established an academic-industrial partnership to develop, validate, and evaluate a multi-modality neurosurgical image-guidance platform for brain tumor resection surgery that is capable of updating the spatial relationships between preoperative images and the current surgical field. A stereovision system has been developed and optimized for intraoperative use through integration with a surgical microscope and an image-guided surgery system. The microscope optics and stereovision CCD sensors are localized relative to the surgical field using optical tracking and can efficiently acquire stereo image pairs from which a localized 3D profile of the exposed surface is reconstructed. This paper reports the first demonstration of intraoperative acquisition, reconstruction and visualization of 3D stereovision surface data in the context of an industry-standard image-guided surgery system. The integrated system is capable of computing and presenting a stereovision-based update of the exposed cortical surface in less than one minute. Alternative methods for visualization of high-resolution, texture-mapped stereovision surface data are also investigated with the objective of determining the technical feasibility of direct incorporation of intraoperative stereo imaging into future iterations of Medtronic's navigation platform.

  9. Interaction of Harsh Weather Operation and Collision Avoidance in Autonomous Navigation

    Directory of Open Access Journals (Sweden)

    Hans-Christoph Burmeister

    2015-03-01

    Full Text Available Taking into account the autonomous navigation system design and today’s state of the art navigation with regards to weather and collision avoidance this paper presents the architecture of the integrated approach, its links to existing rules and regulations and the test scenarios. These demonstrate how safe and efficient navigation of autonomous vessels can be achieved by showing the module's interaction and validating the feasibility of the approach. These analyses will be based on historical traffic data sets as well as simulation results.

  10. Surgical Navigation Technology Based on Augmented Reality and Integrated 3D Intraoperative Imaging: A Spine Cadaveric Feasibility and Accuracy Study.

    Science.gov (United States)

    Elmi-Terander, Adrian; Skulason, Halldor; Söderman, Michael; Racadio, John; Homan, Robert; Babic, Drazenko; van der Vaart, Nijs; Nachabe, Rami

    2016-11-01

    A cadaveric laboratory study. The aim of this study was to assess the feasibility and accuracy of thoracic pedicle screw placement using augmented reality surgical navigation (ARSN). Recent advances in spinal navigation have shown improved accuracy in lumbosacral pedicle screw placement but limited benefits in the thoracic spine. 3D intraoperative imaging and instrument navigation may allow improved accuracy in pedicle screw placement, without the use of x-ray fluoroscopy, and thus opens the route to image-guided minimally invasive therapy in the thoracic spine. ARSN encompasses a surgical table, a motorized flat detector C-arm with intraoperative 2D/3D capabilities, integrated optical cameras for augmented reality navigation, and noninvasive patient motion tracking. Two neurosurgeons placed 94 pedicle screws in the thoracic spine of four cadavers using ARSN on one side of the spine (47 screws) and free-hand technique on the contralateral side. X-ray fluoroscopy was not used for either technique. Four independent reviewers assessed the postoperative scans, using the Gertzbein grading. Morphometric measurements of the pedicles axial and sagittal widths and angles, as well as the vertebrae axial and sagittal rotations were performed to identify risk factors for breaches. ARSN was feasible and superior to free-hand technique with respect to overall accuracy (85% vs. 64%, P dimensions, except for vertebral body axial rotation, were risk factors for larger breaches when performed with the free-hand method. ARSN without fluoroscopy was feasible and demonstrated higher accuracy than free-hand technique for thoracic pedicle screw placement. N/A.

  11. Simple Sensitivity Analysis for Orion Guidance Navigation and Control

    Science.gov (United States)

    Pressburger, Tom; Hoelscher, Brian; Martin, Rodney; Sricharan, Kumar

    2013-01-01

    The performance of Orion flight software, especially its GNC software, is being analyzed by running Monte Carlo simulations of Orion spacecraft flights. The simulated performance is analyzed for conformance with flight requirements, expressed as performance constraints. Flight requirements include guidance (e.g. touchdown distance from target) and control (e.g., control saturation) as well as performance (e.g., heat load constraints). The Monte Carlo simulations disperse hundreds of simulation input variables, for everything from mass properties to date of launch. We describe in this paper a sensitivity analysis tool ("Critical Factors Tool" or CFT) developed to find the input variables or pairs of variables which by themselves significantly influence satisfaction of requirements or significantly affect key performance metrics (e.g., touchdown distance from target). Knowing these factors can inform robustness analysis, can inform where engineering resources are most needed, and could even affect operations. The contributions of this paper include the introduction of novel sensitivity measures, such as estimating success probability, and a technique for determining whether pairs of factors are interacting dependently or independently. The tool found that input variables such as moments, mass, thrust dispersions, and date of launch were found to be significant factors for success of various requirements. Examples are shown in this paper as well as a summary and physics discussion of EFT-1 driving factors that the tool found.

  12. COBALT: A GN&C Payload for Testing ALHAT Capabilities in Closed-Loop Terrestrial Rocket Flights

    Science.gov (United States)

    Carson, John M., III; Amzajerdian, Farzin; Hines, Glenn D.; O'Neal, Travis V.; Robertson, Edward A.; Seubert, Carl; Trawny, Nikolas

    2016-01-01

    The COBALT (CoOperative Blending of Autonomous Landing Technology) payload is being developed within NASA as a risk reduction activity to mature, integrate and test ALHAT (Autonomous precision Landing and Hazard Avoidance Technology) systems targeted for infusion into near-term robotic and future human space flight missions. The initial COBALT payload instantiation is integrating the third-generation ALHAT Navigation Doppler Lidar (NDL) sensor, for ultra high-precision velocity plus range measurements, with the passive-optical Lander Vision System (LVS) that provides Terrain Relative Navigation (TRN) global-position estimates. The COBALT payload will be integrated onboard a rocket-propulsive terrestrial testbed and will provide precise navigation estimates and guidance planning during two flight test campaigns in 2017 (one open-loop and closed- loop). The NDL is targeting performance capabilities desired for future Mars and Moon Entry, Descent and Landing (EDL). The LVS is already baselined for TRN on the Mars 2020 robotic lander mission. The COBALT platform will provide NASA with a new risk-reduction capability to test integrated EDL Guidance, Navigation and Control (GN&C) components in closed-loop flight demonstrations prior to the actual mission EDL.

  13. Intraoperative computed tomography with integrated navigation system in spinal stabilizations.

    Science.gov (United States)

    Zausinger, Stefan; Scheder, Ben; Uhl, Eberhard; Heigl, Thomas; Morhard, Dominik; Tonn, Joerg-Christian

    2009-12-15

    STUDY DESIGN.: A prospective interventional case-series study plus a retrospective analysis of historical patients for comparison of data. OBJECTIVE.: To evaluate workflow, feasibility, and clinical outcome of navigated stabilization procedures with data acquisition by intraoperative computed tomography. SUMMARY OF BACKGROUND DATA.: Routine fluoroscopy to assess pedicle screw placement is not consistently reliable. Our hypothesis was that image-guided spinal navigation using an intraoperative CT-scanner can improve the safety and precision of spinal stabilization surgery. METHODS.: CT data of 94 patients (thoracolumbar [n = 66], C1/2 [n = 12], cervicothoracic instability [n = 16]) were acquired after positioning the patient in the final surgical position. A sliding gantry 40-slice CT was used for image acquisition. Data were imported to a frameless infrared-based neuronavigation workstation. Intraoperative CT was obtained to assess the accuracy of instrumentation and, if necessary, the extent of decompression. All patients were clinically evaluated by Odom-criteria after surgery and after 3 months. RESULTS.: Computed accuracy of the navigation system reached /=2 mm without persistent neurologic or vascular damage in 20/414 screws (4.8%) leading to immediate correction of 10 screws (2.4%). Control-iCT changed the course of surgery in 8 cases (8.5% of all patients). The overall revision rate was 8.5% (4 wound revisions, 2 CSF fistulas, and 2 epidural hematomas). There was no reoperation due to implant malposition. According to Odom-criteria all patients experienced a clinical improvement. A retrospective analysis of 182 patients with navigated thoracolumbar transpedicular stabilizations in the preiCT era revealed an overall revision rate of 10.4% with 4.4% of patients requiring screw revision. CONCLUSION.: Intraoperative CT in combination with neuronavigation provides high accuracy of screw placement and thus safety for patients undergoing spinal stabilization

  14. The Hedgehog Signalling Pathway in Cell Migration and Guidance: What We Have Learned from Drosophila melanogaster

    Directory of Open Access Journals (Sweden)

    Sofia J. Araújo

    2015-10-01

    Full Text Available Cell migration and guidance are complex processes required for morphogenesis, the formation of tumor metastases, and the progression of human cancer. During migration, guidance molecules induce cell directionality and movement through complex intracellular mechanisms. Expression of these molecules has to be tightly regulated and their signals properly interpreted by the receiving cells so as to ensure correct navigation. This molecular control is fundamental for both normal morphogenesis and human disease. The Hedgehog (Hh signaling pathway is evolutionarily conserved and known to be crucial for normal cellular growth and differentiation throughout the animal kingdom. The relevance of Hh signaling for human disease is emphasized by its activation in many cancers. Here, I review the current knowledge regarding the involvement of the Hh pathway in cell migration and guidance during Drosophila development and discuss its implications for human cancer origin and progression.

  15. A Novel Online Data-Driven Algorithm for Detecting UAV Navigation Sensor Faults

    OpenAIRE

    Rui Sun; Qi Cheng; Guanyu Wang; Washington Yotto Ochieng

    2017-01-01

    The use of Unmanned Aerial Vehicles (UAVs) has increased significantly in recent years. On-board integrated navigation sensors are a key component of UAVs’ flight control systems and are essential for flight safety. In order to ensure flight safety, timely and effective navigation sensor fault detection capability is required. In this paper, a novel data-driven Adaptive Neuron Fuzzy Inference System (ANFIS)-based approach is presented for the detection of on-board navigation sensor faults in ...

  16. Intraoperative CT with integrated navigation system in spinal neurosurgery

    International Nuclear Information System (INIS)

    Zausinger, S.; Heigl, T.; Scheder, B.; Schnell, O.; Tonn, J.C.; Uhl, E.; Morhard, D.

    2007-01-01

    For spinal surgery navigational system images are usually acquired before surgery with patients positioned supine. The aim of this study was to evaluate prospectively navigated procedures in spinal surgery with data acquisition by intraoperative computed tomography (iCT). CT data of 38 patients [thoracolumbar instability (n = 24), C1/2 instability (n = 6), cervicothoracic stabilization (n = 7), disk herniation (n = 1)] were acquired after positioning the patient in prone position. A sliding gantry 24 detector row CT was used for image acquisition. Data were imported to the frameless infrared-based neuronavigation station. A postprocedural CT was obtained to assess the extent of decompression and the accuracy of instrumentation. Intraoperative registration revealed computed accuracy 2 mm in 9/158 screws (5.6%), allowing immediate correction in five screws without any damage to vessels or nerves. There were three transient complications with clinical improvement in all patients. Intraoperative CT in combination with neuronavigation provides high accuracy of screw placement and thus safety for patients undergoing spinal stabilization. The procedure is rapid and easy to perform and - by replacing pre- and postoperative imaging-is not associated with additional exposure to radiation. (orig.)

  17. Supporting Development of Satellite's Guidance Navigation and Control Software: A Product Line Approach

    Science.gov (United States)

    McComas, David; Stark, Michael; Leake, Stephen; White, Michael; Morisio, Maurizio; Travassos, Guilherme H.; Powers, Edward I. (Technical Monitor)

    2000-01-01

    The NASA Goddard Space Flight Center Flight Software Branch (FSB) is developing a Guidance, Navigation, and Control (GNC) Flight Software (FSW) product line. The demand for increasingly more complex flight software in less time while maintaining the same level of quality has motivated us to look for better FSW development strategies. The GNC FSW product line has been planned to address the core GNC FSW functionality very similar on many recent low/near Earth missions in the last ten years. Unfortunately these missions have not accomplished significant drops in development cost since a systematic approach towards reuse has not been adopted. In addition, new demands are continually being placed upon the FSW which means the FSB must become more adept at providing GNC FSW functionality's core so it can accommodate additional requirements. These domain features together with engineering concepts are influencing the specification, description and evaluation of FSW product line. Domain engineering is the foundation for emerging product line software development approaches. A product line is 'A family of products designed to take advantage of their common aspects and predicted variabilities'. In our product line approach, domain engineering includes the engineering activities needed to produce reusable artifacts for a domain. Application engineering refers to developing an application in the domain starting from reusable artifacts. The focus of this paper is regarding the software process, lessons learned and on how the GNC FSW product line manages variability. Existing domain engineering approaches do not enforce any specific notation for domain analysis or commonality and variability analysis. Usually, natural language text is the preferred tool. The advantage is the flexibility and adapt ability of natural language. However, one has to be ready to accept also its well-known drawbacks, such as ambiguity, inconsistency, and contradictions. While most domain analysis

  18. The Impact of Integrated Maneuver Guidance Information on UAS Pilots Performing the Detect and Avoid Task

    Science.gov (United States)

    Rorie, Conrad; Fern, Lisa

    2015-01-01

    The integrated human-in-the-loop (iHITL) simulation examined the effect of four different Detect-and-Avoid (DAA) display concepts on unmanned aircraft system (UAS) pilots' ability to maintain safe separation. The displays varied in the type and amount of guidance they provided to pilots. The study's background and methodology are discussed, followed by the 'measured response' data (i.e., pilots' end-to-end response time in reacting to traffic alerts on their DAA display). Results indicate that display type had a significant impact on how long pilot's spent interacting with the interface (i.e., edit times).

  19. An Integrated Vision-Based System for Spacecraft Attitude and Topology Determination for Formation Flight Missions

    Science.gov (United States)

    Rogers, Aaron; Anderson, Kalle; Mracek, Anna; Zenick, Ray

    2004-01-01

    With the space industry's increasing focus upon multi-spacecraft formation flight missions, the ability to precisely determine system topology and the orientation of member spacecraft relative to both inertial space and each other is becoming a critical design requirement. Topology determination in satellite systems has traditionally made use of GPS or ground uplink position data for low Earth orbits, or, alternatively, inter-satellite ranging between all formation pairs. While these techniques work, they are not ideal for extension to interplanetary missions or to large fleets of decentralized, mixed-function spacecraft. The Vision-Based Attitude and Formation Determination System (VBAFDS) represents a novel solution to both the navigation and topology determination problems with an integrated approach that combines a miniature star tracker with a suite of robust processing algorithms. By combining a single range measurement with vision data to resolve complete system topology, the VBAFDS design represents a simple, resource-efficient solution that is not constrained to certain Earth orbits or formation geometries. In this paper, analysis and design of the VBAFDS integrated guidance, navigation and control (GN&C) technology will be discussed, including hardware requirements, algorithm development, and simulation results in the context of potential mission applications.

  20. Data Integration from GPS and Inertial Navigation Systems for Pedestrians in Urban Area

    OpenAIRE

    Krzysztof Bikonis; Jerzy Demkowicz

    2013-01-01

    The GPS system is widely used in navigation and the GPS receiver can offer long-term stable absolute positioning information. The overall system performance depends largely on the signal environments. The position obtained from GPS is often degraded due to obstruction and multipath effect caused by buildings, city infrastructure and vegetation, whereas, the current performance achieved by inertial navigation systems (INS) is still relatively poor due to the large inertial sensor errors. The c...

  1. Monitoring of Entrance Channel Navigation Improvements at Pentwater, Michigan, and Design Guidance for Pocket Wave Absorbers

    National Research Council Canada - National Science Library

    Thompson, Edward F; Myrick, Glenn B; Zager, Nicholas J; Bottin, Jr., Robert R; Sabol, Margaret A; Selegean, James P; McKinney, James P; Demirbilek, Zeki; Acuff, Jr, Hugh F

    2006-01-01

    .... The objectives of the monitoring effort at Pentwater Harbor were to evaluate the design of existing pocket wave absorbers and to develop better design guidance for future pocket wave absorber projects...

  2. Street navigation using visual information on mobile phones

    DEFF Research Database (Denmark)

    Nguyen, Phuong Giang; Andersen, Hans Jørgen; Høilund, Carsten

    2010-01-01

    Applications with street navigation have been recently introduced on mobile phone devices. A major part of existing systems use integrated GPS as input for indicating the location. However, these systems often fail or make abrupt shifts in urban environment due to occlusion of satellites....... Furthermore, they only give the position of a person and not the object of his attention, which is just as important for localization based services. In this paper we introduce a system using mobile phones built-in cameras for navigation and localization using visual information in accordance with the way we...

  3. A Smart Infrared Microcontroller-Based Blind Guidance System

    Directory of Open Access Journals (Sweden)

    Amjed S. Al-Fahoum

    2013-01-01

    Full Text Available Blindness is a state of lacking the visual perception due to physiological or neurological factors. The partial blindness represents the lack of integration in the growth of the optic nerve or visual centre of the eye, and total blindness is the full absence of the visual light perception. In this work, a simple, cheap, friendly user, smart blind guidance system is designed and implemented to improve the mobility of both blind and visually impaired people in a specific area. The proposed work includes a wearable equipment consists of head hat and mini hand stick to help the blind person to navigate alone safely and to avoid any obstacles that may be encountered, whether fixed or mobile, to prevent any possible accident. The main component of this system is the infrared sensor which is used to scan a predetermined area around blind by emitting-reflecting waves. The reflected signals received from the barrier objects are used as inputs to PIC microcontroller. The microcontroller is then used to determine the direction and distance of the objects around the blind. It also controls the peripheral components that alert the user about obstacle's shape, material, and direction. The implemented system is cheap, fast, and easy to use and an innovative affordable solution to blind and visually impaired people in third world countries.

  4. 6TH Saint Petersburg International Conference on Integrated Navigation Systems.

    Science.gov (United States)

    1999-10-01

    pp. 7/1-12. 4. Kharisov V.N., Perov A.I., Boldin VA. (editors). The global satelllite radio-navigational system GLONASS [in Russian]. Moskow: IPRZhR...The need for oil and natural gas requires the techniques for their searching and extracting in deep seas. These techniques have yielded particular

  5. CONTROL OF AIRCRAFT TRAJECTORIES IN THE CONDITIONS OF THE NAVIGATION SESSION OPTIMIZATION AT AUTOMATIC DEPENDENT SURVEILLANCE

    Directory of Open Access Journals (Sweden)

    V. V. Erokhin

    2015-01-01

    Full Text Available Algorithms of determination of coordinates of the aircraft in the integrated system of navigation and optimum control of a trajectory are considered. Results of researches of parameters of a navigation session and precision characteristics of an assessment of location showed that application of optimum control of a trajectory allowув to increase the accuracy of navigation definitions in case of incomplete constellation of navigation satellites.

  6. Integrated vehicle control and guidance systems in unmanned ground vehicles for commercial applications

    Science.gov (United States)

    Kenyon, Chase H.

    1995-01-01

    While there is a lot of recent development in the entire IVHS field, very few have had the opportunity to combine the many areas of development into a single integrated `intelligent' unmanned vehicle. One of our systems was developed specifically to serve a major automobile manufacturer's need for an automated vehicle chassis durability test facility. Due to the severity of the road surface human drivers could not be used. A totally automated robotic vehicle driver and guidance system was necessary. In order to deliver fixed price commercial projects now, it was apparent system and component costs were of paramount importance. Cyplex has developed a robust, cost effective single wire guidance system. This system has inherent advantages in system simplicity. Multi-signal (per vehicle lane) systems complicate path planning and layout when multiple lanes and lane changes are required, as on actual highways. The system has demonstrated high enough immunity to rain and light snow cover that normal safety reductions in speed are adequate to stay within the required system performance envelope. This system and it's antenna interface have shown the ability to guide the vehicle at slow speeds (10 MPH) with a tracking repeatability of plus or minus 1/8 of an inch. The basic guide and antenna system has been tested at speeds up to 80 mph. The system has inherently superior abilities for lane changes and precision vehicle placement. The operation of this system will be described and the impact of a system that is commercially viable now for highway and off road use will be discussed.

  7. Improving Canada's Marine Navigation System through e-Navigation

    Directory of Open Access Journals (Sweden)

    Daniel Breton

    2016-06-01

    The conclusion proposed is that on-going work with key partners and stakeholders can be used as the primary mechanism to identify e-Navigation related innovation and needs, and to prioritize next steps. Moving forward in Canada, implementation of new e-navigation services will continue to be stakeholder driven, and used to drive improvements to Canada's marine navigation system.

  8. The utilization of cranial models created using rapid prototyping techniques in the development of models for navigation training.

    Science.gov (United States)

    Waran, V; Pancharatnam, Devaraj; Thambinayagam, Hari Chandran; Raman, Rajagopal; Rathinam, Alwin Kumar; Balakrishnan, Yuwaraj Kumar; Tung, Tan Su; Rahman, Z A

    2014-01-01

    Navigation in neurosurgery has expanded rapidly; however, suitable models to train end users to use the myriad software and hardware that come with these systems are lacking. Utilizing three-dimensional (3D) industrial rapid prototyping processes, we have been able to create models using actual computed tomography (CT) data from patients with pathology and use these models to simulate a variety of commonly performed neurosurgical procedures with navigation systems. To assess the possibility of utilizing models created from CT scan dataset obtained from patients with cranial pathology to simulate common neurosurgical procedures using navigation systems. Three patients with pathology were selected (hydrocephalus, right frontal cortical lesion, and midline clival meningioma). CT scan data following an image-guidance surgery protocol in DIACOM format and a Rapid Prototyping Machine were taken to create the necessary printed model with the corresponding pathology embedded. The ability in registration, planning, and navigation of two navigation systems using a variety of software and hardware provided by these platforms was assessed. We were able to register all models accurately using both navigation systems and perform the necessary simulations as planned. Models with pathology utilizing 3D rapid prototyping techniques accurately reflect data of actual patients and can be used in the simulation of neurosurgical operations using navigation systems. Georg Thieme Verlag KG Stuttgart · New York.

  9. Navigating on handheld displays: Dynamic versus Static Keyhole Navigation

    NARCIS (Netherlands)

    Mehra, S.; Werkhoven, P.; Worring, M.

    2006-01-01

    Handheld displays leave little space for the visualization and navigation of spatial layouts representing rich information spaces. The most common navigation method for handheld displays is static peephole navigation: The peephole is static and we move the spatial layout behind it (scrolling). A

  10. Celestial Navigation on the Surface of Mars

    Science.gov (United States)

    Malay, Benjamin P.

    2001-05-01

    A simple, accurate, and autonomous method of finding position on the surface of Mars currently does not exist. The goal of this project is to develop a celestial navigation process that will fix a position on Mars with 100-meter accuracy. This method requires knowing the position of the stars and planets referenced to the Martian surface with one arcsecond accuracy. This information is contained in an ephemeris known as the Aeronautical Almanac (from Ares, the god of war) . Naval Observatory Vector Astrometry Subroutines (NOVAS) form the basis of the code used to generate the almanac. Planetary position data come the JPL DE405 Planetary Ephemeris. The theoretical accuracy of the almanac is determined mathematically and compared with the Ephemeris for Physical Observations of Mars contained in the Astronautical Almanac. A preliminary design of an autonomous celestial navigation system is presented. Recommendations of how to integrate celestial navigation into NASA=s current Mars exploration program are also discussed. This project is a useful and much-needed first step towards establishing celestial navigation as a practical way to find position on the surface of Mars.

  11. Guidance and control 1992; Proceedings of the 15th Annual AAS Rocky Mountain Conference, Keystone, CO, Feb. 8-12, 1992

    Science.gov (United States)

    Culp, Robert D.; Zietz, Richard P.

    The present volume on guidance and control discusses advances in guidance, navigation, and control, guidance and control storyboard displays, space robotic control, spacecraft control and flexible body interaction, and the Mission to Planet Earth. Attention is given to applications of Newton's method to attitude determination, a new family of low-cost momentum/reaction wheels, stellar attitude data handling, and satellite life prediction using propellant quantity measurements. Topics addressed include robust manipulator controller specification and design, implementations and applications of a manipulator control testbed, optimizing transparency in teleoperator architectures, and MIMO system identification using frequency response data. Also discussed are instrument configurations for the restructured Earth Observing System, the HIRIS instrument, clouds and the earth's radiant energy system, and large space-based systems for dealing with global change.

  12. A Self-Tuning Kalman Filter for Autonomous Navigation using the Global Positioning System (GPS)

    Science.gov (United States)

    Truong, S. H.

    1999-01-01

    Most navigation systems currently operated by NASA are ground-based, and require extensive support to produce accurate results. Recently developed systems that use Kalman filter and GPS data for orbit determination greatly reduce dependency on ground support, and have potential to provide significant economies for NASA spacecraft navigation. These systems, however, still rely on manual tuning from analysts. A sophisticated neuro-fuzzy component fully integrated with the flight navigation system can perform the self-tuning capability for the Kalman filter and help the navigation system recover from estimation errors in real time.

  13. Feasibility Study of Needle Placement in Percutaneous Vertebroplasty: Cone-Beam Computed Tomography Guidance Versus Conventional Fluoroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Braak, Sicco J., E-mail: sjbraak@gmail.com [St. Antonius Hospital, Department of Radiology (Netherlands); Zuurmond, Kirsten, E-mail: kirsten.zuurmond@philips.com; Aerts, Hans C. J., E-mail: hans.cj.aerts@philips.com [Philips Medical, Department of Clinical Development (Netherlands); Leersum, Marc van, E-mail: m.van.leersum@antoniusziekenhuis.nl; Overtoom, Timotheus T. Th., E-mail: overtm@knoware.nl; Heesewijk, Johannes P. M. van, E-mail: j.heesewijk@antoniusziekenhuis.nl; Strijen, Marco J. L. van, E-mail: m.van.strijen@antoniusziekenhuis.nl [St. Antonius Hospital, Department of Radiology (Netherlands)

    2013-08-01

    ObjectiveTo investigate the accuracy, procedure time, fluoroscopy time, and dose area product (DAP) of needle placement during percutaneous vertebroplasty (PVP) using cone-beam computed tomography (CBCT) guidance versus fluoroscopy.Materials and MethodsOn 4 spine phantoms with 11 vertebrae (Th7-L5), 4 interventional radiologists (2 experienced with CBCT guidance and two inexperienced) punctured all vertebrae in a bipedicular fashion. Each side was randomization to either CBCT guidance or fluoroscopy. CBCT guidance is a sophisticated needle guidance technique using CBCT, navigation software, and real-time fluoroscopy. The placement of the needle had to be to a specific target point. After the procedure, CBCT was performed to determine the accuracy, procedure time, fluoroscopy time, and DAP. Analysis of the difference between methods and experience level was performed.ResultsMean accuracy using CBCT guidance (2.61 mm) was significantly better compared with fluoroscopy (5.86 mm) (p < 0.0001). Procedure time was in favor of fluoroscopy (7.39 vs. 10.13 min; p = 0.001). Fluoroscopy time during CBCT guidance was lower, but this difference is not significant (71.3 vs. 95.8 s; p = 0.056). DAP values for CBCT guidance and fluoroscopy were 514 and 174 mGy cm{sup 2}, respectively (p < 0.0001). There was a significant difference in favor of experienced CBCT guidance users regarding accuracy for both methods, procedure time of CBCT guidance, and added DAP values for fluoroscopy.ConclusionCBCT guidance allows users to perform PVP more accurately at the cost of higher patient dose and longer procedure time. Because procedural complications (e.g., cement leakage) are related to the accuracy of the needle placement, improvements in accuracy are clinically relevant. Training in CBCT guidance is essential to achieve greater accuracy and decrease procedure time/dose values.

  14. The neonicotinoid clothianidin interferes with navigation of the solitary bee Osmia cornuta in a laboratory test.

    Science.gov (United States)

    Jin, Nanxiang; Klein, Simon; Leimig, Fabian; Bischoff, Gabriela; Menzel, Randolf

    2015-09-01

    Pollinating insects provide a vital ecosystem service to crops and wild plants. Exposure to low doses of neonicotinoid insecticides has sub-lethal effects on social pollinators such as bumblebees and honeybees, disturbing their navigation and interfering with their development. Solitary Hymenoptera are also very important ecosystem service providers, but the sub-lethal effects of neonicotinoids have not yet been studied well in those animals. We analyzed the ability of walking Osmia to remember a feeding place in a small environment and found that Osmia remembers the feeding place well after 4 days of training. Uptake of field-realistic amounts of the neonicotinoid clothianidin (0.76 ng per bee) altered the animals' sensory responses to the visual environment and interfered with the retrieval of navigational memory. We conclude that the neonicotinoid clothianidin compromises visual guidance and the use of navigational memory in the solitary bee Osmia cornuta. © 2015. Published by The Company of Biologists Ltd.

  15. Deliverable D.8.4. Social data visualization and navigation services -3rd Year Update-

    NARCIS (Netherlands)

    Bitter-Rijpkema, Marlies; Brouns, Francis; Drachsler, Hendrik; Fazeli, Soude; Sanchez-Alonso, Salvador; Rajabi, Enayat; Kolovou, Lamprini

    2015-01-01

    Within the Open Discovery Space our study (T.8.4) focused on ”Enhanced Social Data Visualization & Navigation Services. This deliverable provides the prototype report regarding the deployment of adapted visualization and navigation services to be integrated in the ODS Social Data Management Layer.

  16. A novel personal health system with integrated decision support and guidance for the management of chronic liver disease.

    Science.gov (United States)

    Kiefer, Stephan; Schäfer, Michael; Bransch, Marco; Brimmers, Peter; Bartolomé, Diego; Baños, Janie; Orr, James; Jones, Dave; Jara, Maximilian; Stockmann, Martin

    2014-01-01

    A personal health system platform for the management of patients with chronic liver disease that incorporates a novel approach to integrate decision support and guidance through care pathways for patients and their doctors is presented in this paper. The personal health system incorporates an integrated decision support engine that guides patients and doctors through the management of the disease by issuing tasks and providing recommendations to both the care team and the patient and by controlling the execution of a Care Flow Plan based on the results of tasks and the monitored health status of the patient. This Care Flow Plan represents a formal, business process based model of disease management designed off-line by domain experts on the basis of clinical guidelines, knowledge of care pathways and an organisational model for integrated, patient-centred care. In this way, remote monitoring and treatment are dynamically adapted to the patient's actual condition and clinical symptoms and allow flexible delivery of care with close integration of specialists, therapists and care-givers.

  17. Triply redundant integrated navigation and asset visibility system

    Science.gov (United States)

    Smith, Stephen F [Loudon, TN; Moore, James A [Powell, TN

    2011-11-29

    Methods and apparatus are described for a navigation system. A method includes providing a global positioning system fix having a plurality of tracking parameters; providing a theater positioning system fix; monitoring the plurality of tracking parameters for predetermined conditions; and, when the predetermined conditions are met, sending a notifying signal and switching to the theater positioning system fix as a primary fix. An apparatus includes a system controller; a global positioning system receiver coupled to the system controller; a radio frequency locating receiver coupled to the system controller; and an operator interface coupled to the system controller.

  18. Navigation system for robot-assisted intra-articular lower-limb fracture surgery.

    Science.gov (United States)

    Dagnino, Giulio; Georgilas, Ioannis; Köhler, Paul; Morad, Samir; Atkins, Roger; Dogramadzi, Sanja

    2016-10-01

    In the surgical treatment for lower-leg intra-articular fractures, the fragments have to be positioned and aligned to reconstruct the fractured bone as precisely as possible, to allow the joint to function correctly again. Standard procedures use 2D radiographs to estimate the desired reduction position of bone fragments. However, optimal correction in a 3D space requires 3D imaging. This paper introduces a new navigation system that uses pre-operative planning based on 3D CT data and intra-operative 3D guidance to virtually reduce lower-limb intra-articular fractures. Physical reduction in the fractures is then performed by our robotic system based on the virtual reduction. 3D models of bone fragments are segmented from CT scan. Fragments are pre-operatively visualized on the screen and virtually manipulated by the surgeon through a dedicated GUI to achieve the virtual reduction in the fracture. Intra-operatively, the actual position of the bone fragments is provided by an optical tracker enabling real-time 3D guidance. The motion commands for the robot connected to the bone fragment are generated, and the fracture physically reduced based on the surgeon's virtual reduction. To test the system, four femur models were fractured to obtain four different distal femur fracture types. Each one of them was subsequently reduced 20 times by a surgeon using our system. The navigation system allowed an orthopaedic surgeon to virtually reduce the fracture with a maximum residual positioning error of [Formula: see text] (translational) and [Formula: see text] (rotational). Correspondent physical reductions resulted in an accuracy of 1.03 ± 0.2 mm and [Formula: see text], when the robot reduced the fracture. Experimental outcome demonstrates the accuracy and effectiveness of the proposed navigation system, presenting a fracture reduction accuracy of about 1 mm and [Formula: see text], and meeting the clinical requirements for distal femur fracture reduction procedures.

  19. INFORMATION AS AN ELEMENT OF THE NAVIGATION DECISIONMAKING PROCESS

    Directory of Open Access Journals (Sweden)

    Andrzej BANACHOWICZ

    2016-09-01

    Full Text Available The operation of vehicles (watercraft, aircraft, land-based, spacecraft, unmanned requires the use of navigation systems for their control. These systems can be characterized by varying degrees of complexity and technological advancement. However, each system has sources of information about the state (position of the navigating object, state of the environment in which the object is moving and the task to be accomplished. These components are integrated by the decision-maker (human or automated, who/which makes and implements decisions adjusted to current conditions

  20. Theoretical Limits of Lunar Vision Aided Navigation with Inertial Navigation System

    Science.gov (United States)

    2015-03-26

    THEORETICAL LIMITS OF LUNAR VISION AIDED NAVIGATION WITH INERTIAL NAVIGATION SYSTEM THESIS David W. Jones, Capt, USAF AFIT-ENG-MS-15-M-020 DEPARTMENT...Government and is not subject to copyright protection in the United States. AFIT-ENG-MS-15-M-020 THEORETICAL LIMITS OF LUNAR VISION AIDED NAVIGATION WITH...DISTRIBUTION UNLIMITED. AFIT-ENG-MS-15-M-020 THEORETICAL LIMITS OF LUNAR VISION AIDED NAVIGATION WITH INERTIAL NAVIGATION SYSTEM THESIS David W. Jones

  1. Sacro-iliac joint arthrography in low back pain: feasibility of MRI guidance

    International Nuclear Information System (INIS)

    Ojala, Risto; Klemola, Rauli; Karppinen, Jaro; Sequeiros, Roberto Blanco; Tervonen, Osmo

    2001-01-01

    Objective: Evaluation of the feasibility of MR-guidance in sacro-iliac joint arthrography in patients whose low back pain is suspected to arise from the sacro-iliac joint (SIJ). Methods and patients: Twenty patients with low back pain underwent MR-guided sacro-iliac joint arthrography. Needles made from titanium (size 20 G, MDTech, USA) were used. For image guidance a 0.23T open-configuration C arm magnet (Proview, Marconi Medical Systems, USA) with special interventional hardware and software package (I-Path 200, Marconi Medical Systems) containing an MR compatible in-room console, large-screen (36'') display, optical navigator and accompanying software with dedicated sequences was used. No other image guidance modalities were used. Results: MR-guided SIJ arthrography was successfully performed in all twenty patients without complications. The optimal imaging sequence both for preoperative and intraoperative images was 3D-Gradient Echo sequence. The dispersal of the injected saline and anaesthetic could be determined inside the joint in all cases with heavily T2-weighted fast spin echo sequence. In the present study, 60% of the patients had significant reduction of pain after sacro-iliac joint arthrography and sacro-iliac joint was considered to be the source of patients low back pain in these patients. Conclusion: The present study shows that MR guidance with open configuration low field scanner is an accurate guiding method for sacro-iliac joint arthrography

  2. DVL Velocity Aiding in the HUGIN 1000 Integrated Inertial Navigation System

    Directory of Open Access Journals (Sweden)

    Bjørn Jalving

    2004-10-01

    Full Text Available The RDI WHN-600 Doppler Velocity Log (DVL is a key navigation sensor for the HUG1N 1000 Autonomous Underwater Vehicle (AUV. HUGIN 1000 is designed for autonomous submerged operation for long periods of time. This is facilitated by a low drift velocity aided Inertial Navigation System (INS. Major factors determining the position error growth are the IMU and DVL error characteristics and the mission plan pattern_ For instance, low frequency DVL errors cause an approximately linear drift in a straight-line trajectory, while these errors tend to be cancelled out by a lawn mower pattern_ The paper focuses on the accuracy offered by the DVL. HUGIN 1000 is a permanent organic mine countermeasure (MCM capacity on the Royal Norwegian Navy MCM vessel KNM Karmoy. HUGIN 1000 will be part of the NATO force MCMFORNORTH in fall 2004.

  3. The Navigation Guide - evidence-based medicine meets environmental health: integration of animal and human evidence for PFOA effects on fetal growth.

    Science.gov (United States)

    Lam, Juleen; Koustas, Erica; Sutton, Patrice; Johnson, Paula I; Atchley, Dylan S; Sen, Saunak; Robinson, Karen A; Axelrad, Daniel A; Woodruff, Tracey J

    2014-10-01

    The Navigation Guide is a novel systematic review method to synthesize scientific evidence and reach strength of evidence conclusions for environmental health decision making. Our aim was to integrate scientific findings from human and nonhuman studies to determine the overall strength of evidence for the question "Does developmental exposure to perfluorooctanoic acid (PFOA) affect fetal growth in humans?" We developed and applied prespecified criteria to systematically and transparently a) rate the quality of the scientific evidence as "high," "moderate," or "low"; b) rate the strength of the human and nonhuman evidence separately as "sufficient," "limited," "moderate," or "evidence of lack of toxicity"; and c) integrate the strength of the human and nonhuman evidence ratings into a strength of the evidence conclusion. We identified 18 epidemiology studies and 21 animal toxicology studies relevant to our study question. We rated both the human and nonhuman mammalian evidence as "moderate" quality and "sufficient" strength. Integration of these evidence ratings produced a final strength of evidence rating in which review authors concluded that PFOA is "known to be toxic" to human reproduction and development based on sufficient evidence of decreased fetal growth in both human and nonhuman mammalian species. We concluded that developmental exposure to PFOA adversely affects human health based on sufficient evidence of decreased fetal growth in both human and nonhuman mammalian species. The results of this case study demonstrate the application of a systematic and transparent methodology, via the Navigation Guide, for reaching strength of evidence conclusions in environmental health.

  4. Guidance of retinal axons in mammals.

    Science.gov (United States)

    Herrera, Eloísa; Erskine, Lynda; Morenilla-Palao, Cruz

    2017-11-26

    In order to navigate through the surrounding environment many mammals, including humans, primarily rely on vision. The eye, composed of the choroid, sclera, retinal pigmented epithelium, cornea, lens, iris and retina, is the structure that receives the light and converts it into electrical impulses. The retina contains six major types of neurons involving in receiving and modifying visual information and passing it onto higher visual processing centres in the brain. Visual information is relayed to the brain via the axons of retinal ganglion cells (RGCs), a projection known as the optic pathway. The proper formation of this pathway during development is essential for normal vision in the adult individual. Along this pathway there are several points where visual axons face 'choices' in their direction of growth. Understanding how these choices are made has advanced significantly our knowledge of axon guidance mechanisms. Thus, the development of the visual pathway has served as an extremely useful model to reveal general principles of axon pathfinding throughout the nervous system. However, due to its particularities, some cellular and molecular mechanisms are specific for the visual circuit. Here we review both general and specific mechanisms involved in the guidance of mammalian RGC axons when they are traveling from the retina to the brain to establish precise and stereotyped connections that will sustain vision. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Approach to intraoperative electromagnetic navigation in orthognathic surgery: A phantom skull based trial.

    Science.gov (United States)

    Berger, Moritz; Kallus, Sebastian; Nova, Igor; Ristow, Oliver; Eisenmann, Urs; Dickhaus, Hartmut; Kuhle, Reinald; Hoffmann, Jürgen; Seeberger, Robin

    2015-11-01

    Intraoperative guidance using electromagnetic navigation is an upcoming method in maxillofacial surgery. However, due to their unwieldy structures, especially the line-of-sight problem, optical navigation devices are not used for daily orthognathic surgery. Therefore, orthognathic surgery was simulated on study phantom skulls, evaluating the accuracy and handling of a new electromagnetic tracking system. Le-Fort I osteotomies were performed on 10 plastic skulls. Orthognathic surgical planning was done in the conventional way using plaster models. Accuracy of the gold standard, splint-based model surgery versus an electromagnetic tracking system was evaluated by measuring the actual maxillary deviation using bimaxillary splints and preoperative and postoperative cone beam computer tomography imaging. The distance of five anatomical marker points were compared pre- and postoperatively. The electromagnetic tracking system was significantly more accurate in all measured parameters compared with the gold standard using bimaxillary splints (p orthognathic surgery to 0.3 mm on average. The data of this preliminary study shows a high level of accuracy in surgical orthognathic performance using electromagnetic navigation, and may offer greater precision than the conventional plaster model surgery with bimaxillary splints. This preliminary work shows great potential for the establishment of an intraoperative electromagnetic navigation system for maxillofacial surgery. Copyright © 2015 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  6. Deep sea AUV navigation using multiple acoustic beacons

    Science.gov (United States)

    Ji, Da-xiong; Song, Wei; Zhao, Hong-yu; Liu, Jian

    2016-04-01

    Navigation is a critical requirement for the operation of Autonomous Underwater Vehicles (AUVs). To estimate the vehicle position, we present an algorithm using an extended Kalman filter (EKF) to integrate dead-reckoning position with acoustic ranges from multiple beacons pre-deployed in the operating environment. Owing to high latency, variable sound speed multipath transmissions and unreliability in acoustic measurements, outlier recognition techniques are proposed as well. The navigation algorithm has been tested by the recorded data of deep sea AUV during field operations in a variety of environments. Our results show the improved performance over prior techniques based on position computation.

  7. Particle Filter Based Fault-tolerant ROV Navigation using Hydro-acoustic Position and Doppler Velocity Measurements

    DEFF Research Database (Denmark)

    Zhao, Bo; Blanke, Mogens; Skjetne, Roger

    2012-01-01

    This paper presents a fault tolerant navigation system for a remotely operated vehicle (ROV). The navigation system uses hydro-acoustic position reference (HPR) and Doppler velocity log (DVL) measurements to achieve an integrated navigation. The fault tolerant functionality is based on a modied...... particle lter. This particle lter is able to run in an asynchronous manner to accommodate the measurement drop out problem, and it overcomes the measurement outliers by switching observation models. Simulations with experimental data show that this fault tolerant navigation system can accurately estimate...

  8. Neural systems analysis of decision making during goal-directed navigation.

    Science.gov (United States)

    Penner, Marsha R; Mizumori, Sheri J Y

    2012-01-01

    The ability to make adaptive decisions during goal-directed navigation is a fundamental and highly evolved behavior that requires continual coordination of perceptions, learning and memory processes, and the planning of behaviors. Here, a neurobiological account for such coordination is provided by integrating current literatures on spatial context analysis and decision-making. This integration includes discussions of our current understanding of the role of the hippocampal system in experience-dependent navigation, how hippocampal information comes to impact midbrain and striatal decision making systems, and finally the role of the striatum in the implementation of behaviors based on recent decisions. These discussions extend across cellular to neural systems levels of analysis. Not only are key findings described, but also fundamental organizing principles within and across neural systems, as well as between neural systems functions and behavior, are emphasized. It is suggested that studying decision making during goal-directed navigation is a powerful model for studying interactive brain systems and their mediation of complex behaviors. Copyright © 2011. Published by Elsevier Ltd.

  9. Interactive navigation-guided ophthalmic plastic surgery: the utility of 3D CT-DCG-guided dacryolocalization in secondary acquired lacrimal duct obstructions

    Directory of Open Access Journals (Sweden)

    Ali MJ

    2016-12-01

    Full Text Available Mohammad Javed Ali,1 Swati Singh,1 Milind N Naik,1 Swathi Kaliki,2 Tarjani Vivek Dave1 1Govindram Seksaria Institute of Dacryology, 2The Operation Eyesight Universal Institute for Eye Cancer, L V Prasad Eye Institute, Hyderabad, Telangana, India Aim: The aim of this study was to report the preliminary experience with the techniques and utility of navigation-guided, 3D, computed tomography–dacryocystography (CT-DCG in the management of secondary acquired lacrimal drainage obstructions.Methods: Stereotactic surgeries using CT-DCG as the intraoperative image-guiding tool were performed in 3 patients. One patient had nasolacrimal duct obstruction (NLDO following a complete maxillectomy for a sinus malignancy, and the other 2 had NLDO following extensive maxillofacial trauma. All patients underwent a 3D CT-DCG. Image-guided dacryolocalization (IGDL was performed using the intraoperative image-guided StealthStation™ system in the electromagnetic mode. All patients underwent navigation-guided powered endoscopic dacryocystorhinostomy (DCR. The utility of intraoperative dacryocystographic guidance and the ability to localize the lacrimal drainage system in the altered endoscopic anatomical milieu were noted.Results: Intraoperative geometric localization of the lacrimal sac and the nasolacrimal duct could be easily achieved. Constant orientation of the lacrimal drainage system was possible while navigating in the vicinity of altered endoscopic perilacrimal anatomy. Useful clues with regard to modifications while performing a powered endoscopic DCR could be obtained. Surgeries could be performed with utmost safety and precision, thereby avoiding complications. Detailed preoperative 3D CT-DCG reconstructions with constant intraoperative dacryolocalization were found to be essential for successful outcomes.Conclusion: The 3D CT-DCG-guided navigation procedure is very useful while performing endoscopic DCRs in cases of secondary acquired and complex

  10. LATENCY DETERMINATION AND COMPENSATION IN REAL-TIME GNSS/INS INTEGRATED NAVIGATION SYSTEMS

    Directory of Open Access Journals (Sweden)

    P. D. Solomon

    2012-09-01

    Full Text Available Unmanned Aerial Vehicle (UAV technology is now commonplace in many defence and civilian environments. However, the high cost of owning and operating a sophisticated UAV has slowed their adoption in many commercial markets. Universities and research groups are actively experimenting with UAVs to further develop the technology, particularly for automated flying operations. The two main UAV platforms used are fixed-wing and helicopter. Helicopter-based UAVs offer many attractive features over fixed-wing UAVs, including vertical take-off, the ability to loiter, and highly dynamic flight. However the control and navigation of helicopters are significantly more demanding than those of fixed-wing UAVs and as such require a high bandwidth real-time Position, Velocity, Attitude (PVA navigation system. In practical Real-Time Navigation Systems (RTNS there are delays in the processing of the GNSS data prior to the fusion of the GNSS data with the INS measurements. This latency must be compensated for otherwise it degrades the solution of the navigation filter. This paper investigates the effect of latency in the arrival time of the GNSS data in a RTNS. Several test drives and flights were conducted with a low-cost RTNS, and compared with a high quality GNSS/INS solution. A technique for the real-time, automated and accurate estimation of the GNSS latency in low-cost systems was developed and tested. The latency estimates were then verified through cross-correlation with the time-stamped measurements from the reference system. A delayed measurement Extended Kalman Filter was then used to allow for the real-time fusing of the delayed measurements, and then a final system developed for on-the-fly measurement and compensation of GNSS latency in a RTNS.

  11. Latency Determination and Compensation in Real-Time Gnss/ins Integrated Navigation Systems

    Science.gov (United States)

    Solomon, P. D.; Wang, J.; Rizos, C.

    2011-09-01

    Unmanned Aerial Vehicle (UAV) technology is now commonplace in many defence and civilian environments. However, the high cost of owning and operating a sophisticated UAV has slowed their adoption in many commercial markets. Universities and research groups are actively experimenting with UAVs to further develop the technology, particularly for automated flying operations. The two main UAV platforms used are fixed-wing and helicopter. Helicopter-based UAVs offer many attractive features over fixed-wing UAVs, including vertical take-off, the ability to loiter, and highly dynamic flight. However the control and navigation of helicopters are significantly more demanding than those of fixed-wing UAVs and as such require a high bandwidth real-time Position, Velocity, Attitude (PVA) navigation system. In practical Real-Time Navigation Systems (RTNS) there are delays in the processing of the GNSS data prior to the fusion of the GNSS data with the INS measurements. This latency must be compensated for otherwise it degrades the solution of the navigation filter. This paper investigates the effect of latency in the arrival time of the GNSS data in a RTNS. Several test drives and flights were conducted with a low-cost RTNS, and compared with a high quality GNSS/INS solution. A technique for the real-time, automated and accurate estimation of the GNSS latency in low-cost systems was developed and tested. The latency estimates were then verified through cross-correlation with the time-stamped measurements from the reference system. A delayed measurement Extended Kalman Filter was then used to allow for the real-time fusing of the delayed measurements, and then a final system developed for on-the-fly measurement and compensation of GNSS latency in a RTNS.

  12. Satellite Imagery Assisted Road-Based Visual Navigation System

    Science.gov (United States)

    Volkova, A.; Gibbens, P. W.

    2016-06-01

    There is a growing demand for unmanned aerial systems as autonomous surveillance, exploration and remote sensing solutions. Among the key concerns for robust operation of these systems is the need to reliably navigate the environment without reliance on global navigation satellite system (GNSS). This is of particular concern in Defence circles, but is also a major safety issue for commercial operations. In these circumstances, the aircraft needs to navigate relying only on information from on-board passive sensors such as digital cameras. An autonomous feature-based visual system presented in this work offers a novel integral approach to the modelling and registration of visual features that responds to the specific needs of the navigation system. It detects visual features from Google Earth* build a feature database. The same algorithm then detects features in an on-board cameras video stream. On one level this serves to localise the vehicle relative to the environment using Simultaneous Localisation and Mapping (SLAM). On a second level it correlates them with the database to localise the vehicle with respect to the inertial frame. The performance of the presented visual navigation system was compared using the satellite imagery from different years. Based on comparison results, an analysis of the effects of seasonal, structural and qualitative changes of the imagery source on the performance of the navigation algorithm is presented. * The algorithm is independent of the source of satellite imagery and another provider can be used

  13. A code guidance system for integrated nuclear data evaluation system on the basis of knowledge engineering technology

    International Nuclear Information System (INIS)

    Fukahori, Tokio; Nakagawa, Tsuneo

    1994-01-01

    The integrated nuclear data evaluation system (INDES) is being made in order to support the nuclear data evaluation work. A guidance system in INDES, 'Evaluation Tutor (ET)', is under development in order to support users in selecting the most suitable set of theoretical calculation codes by applying knowledge engineering technology and the experiences of evaluation work for JENDL-3. In this paper, the function of ET is introduced as well as the functions and databases of INDES. An example run of ET for 56 Fe in the 1-20 MeV neutron energy region is also explained. (author)

  14. Finding Home: Landmark Ambiguity in Human Navigation

    Directory of Open Access Journals (Sweden)

    Simon Jetzschke

    2017-07-01

    Full Text Available Memories of places often include landmark cues, i.e., information provided by the spatial arrangement of distinct objects with respect to the target location. To study how humans combine landmark information for navigation, we conducted two experiments: To this end, participants were either provided with auditory landmarks while walking in a large sports hall or with visual landmarks while walking on a virtual-reality treadmill setup. We found that participants cannot reliably locate their home position due to ambiguities in the spatial arrangement when only one or two uniform landmarks provide cues with respect to the target. With three visual landmarks that look alike, the task is solved without ambiguity, while audio landmarks need to play three unique sounds for a similar performance. This reduction in ambiguity through integration of landmark information from 1, 2, and 3 landmarks is well modeled using a probabilistic approach based on maximum likelihood estimation. Unlike any deterministic model of human navigation (based e.g., on distance or angle information, this probabilistic model predicted both the precision and accuracy of the human homing performance. To further examine how landmark cues are integrated we introduced systematic conflicts in the visual landmark configuration between training of the home position and tests of the homing performance. The participants integrated the spatial information from each landmark near-optimally to reduce spatial variability. When the conflict becomes big, this integration breaks down and precision is sacrificed for accuracy. That is, participants return again closer to the home position, because they start ignoring the deviant third landmark. Relying on two instead of three landmarks, however, goes along with responses that are scattered over a larger area, thus leading to higher variability. To model the breakdown of integration with increasing conflict, the probabilistic model based on a

  15. Navigation Aiding by a Hybrid Laser-Camera Motion Estimator for Micro Aerial Vehicles

    Directory of Open Access Journals (Sweden)

    Jamal Atman

    2016-09-01

    Full Text Available Micro Air Vehicles (MAVs equipped with various sensors are able to carry out autonomous flights. However, the self-localization of autonomous agents is mostly dependent on Global Navigation Satellite Systems (GNSS. In order to provide an accurate navigation solution in absence of GNSS signals, this article presents a hybrid sensor. The hybrid sensor is a deep integration of a monocular camera and a 2D laser rangefinder so that the motion of the MAV is estimated. This realization is expected to be more flexible in terms of environments compared to laser-scan-matching approaches. The estimated ego-motion is then integrated in the MAV’s navigation system. However, first, the knowledge about the pose between both sensors is obtained by proposing an improved calibration method. For both calibration and ego-motion estimation, 3D-to-2D correspondences are used and the Perspective-3-Point (P3P problem is solved. Moreover, the covariance estimation of the relative motion is presented. The experiments show very accurate calibration and navigation results.

  16. Navigation Aiding by a Hybrid Laser-Camera Motion Estimator for Micro Aerial Vehicles.

    Science.gov (United States)

    Atman, Jamal; Popp, Manuel; Ruppelt, Jan; Trommer, Gert F

    2016-09-16

    Micro Air Vehicles (MAVs) equipped with various sensors are able to carry out autonomous flights. However, the self-localization of autonomous agents is mostly dependent on Global Navigation Satellite Systems (GNSS). In order to provide an accurate navigation solution in absence of GNSS signals, this article presents a hybrid sensor. The hybrid sensor is a deep integration of a monocular camera and a 2D laser rangefinder so that the motion of the MAV is estimated. This realization is expected to be more flexible in terms of environments compared to laser-scan-matching approaches. The estimated ego-motion is then integrated in the MAV's navigation system. However, first, the knowledge about the pose between both sensors is obtained by proposing an improved calibration method. For both calibration and ego-motion estimation, 3D-to-2D correspondences are used and the Perspective-3-Point (P3P) problem is solved. Moreover, the covariance estimation of the relative motion is presented. The experiments show very accurate calibration and navigation results.

  17. The Use of Vocational Guidance E-Systems in Colleges of Technology, Saudi Arabia

    Science.gov (United States)

    Alsaidan, Saad; Zhang, Li

    2018-01-01

    This study aimed to explore how much interest do technical colleges students have in vocational guidance E-Systems and to detect the most important E-Systems of vocational guidance that they use. The researcher collected data, through questionnaires, from 311 students in their fourth, fifth, or sixth semesters in the colleges of technology in Saudi Arabia. The data were analysed using the chi square test, factor analysis, and descriptive analysis. This study shows the importance in the integration of the E-Systems to vocational guidance. The model includes: the use of e-vocational consulting programs, e-extracurricular programs, e-vocational activities, informational systems, and e-exams for vocational tendency, which were rarely studied before. The results indicated that the college student is highly motivated by vocational guidance using the E-system, unlike the traditional methods of vocational guidance, and young students are motivated by the E-system when it is used in vocational guidance. The study conclude that the integration of the E-system has significantly contributed to vocational guidance. The study recommends that the e-system be implemented to all areas of decision-making. Practitioners should Interact with students through the E-Systems and arrive at decisions that are good for educational growth.

  18. Orion Powered Flight Guidance Burn Options for Near Term Exploration

    Science.gov (United States)

    Fill, Tom; Goodman, John; Robinson, Shane

    2018-01-01

    NASA's Orion exploration spacecraft will fly more demanding mission profiles than previous NASA human flight spacecraft. Missions currently under development are destined for cislunar space. The EM-1 mission will fly unmanned to a Distant Retrograde Orbit (DRO) around the Moon. EM-2 will fly astronauts on a mission to the lunar vicinity. To fly these missions, Orion requires powered flight guidance that is more sophisticated than the orbital guidance flown on Apollo and the Space Shuttle. Orion's powered flight guidance software contains five burn guidance options. These five options are integrated into an architecture based on a proven shuttle heritage design, with a simple closed-loop guidance strategy. The architecture provides modularity, simplicity, versatility, and adaptability to future, yet-to-be-defined, exploration mission profiles. This paper provides a summary of the executive guidance architecture and details the five burn options to support both the nominal and abort profiles for the EM-1 and EM-2 missions.

  19. Integrated Guidance and Control Based Air-to-Air Autonomous Attack Occupation of UCAV

    Directory of Open Access Journals (Sweden)

    Chang Luo

    2016-01-01

    Full Text Available An approach of air-to-air autonomous attack occupation for Unmanned Combat Aerial Vehicles (UCAVs is proposed to improve attack precision and combat effectiveness. According to the shortage of UCAV in the task of attack occupation, kinematic and dynamic models of UCAV and missile loaded on it are formed. Then, attack zone and no-escape zone are calculated by pattern search algorithm, and the optimum attack position is indicated. To arrive at the optimum attack position accurately with restriction of gesture, a novel adaptive sliding mode control method is suggested to design the integrated guidance and control system of UCAV in the process of autonomous attack occupation. Key parameters of the control system are adaptively regulated, which further economize control energy at the same time. The simulation results show that compared with traditional methods our approach can guide the UCAV to the optimum attack position with stable gesture and economize nearly 25% control energy.

  20. Design and Evaluation of Shape-Changing Haptic Interfaces for Pedestrian Navigation Assistance.

    Science.gov (United States)

    Spiers, Adam J; Dollar, Aaron M

    2017-01-01

    Shape-changing interfaces are a category of device capable of altering their form in order to facilitate communication of information. In this work, we present a shape-changing device that has been designed for navigation assistance. 'The Animotus' (previously, 'The Haptic Sandwich' ), resembles a cube with an articulated upper half that is able to rotate and extend (translate) relative to the bottom half, which is fixed in the user's grasp. This rotation and extension, generally felt via the user's fingers, is used to represent heading and proximity to navigational targets. The device is intended to provide an alternative to screen or audio based interfaces for visually impaired, hearing impaired, deafblind, and sighted pedestrians. The motivation and design of the haptic device is presented, followed by the results of a navigation experiment that aimed to determine the role of each device DOF, in terms of facilitating guidance. An additional device, 'The Haptic Taco', which modulated its volume in response to target proximity (negating directional feedback), was also compared. Results indicate that while the heading (rotational) DOF benefited motion efficiency, the proximity (translational) DOF benefited velocity. Combination of the two DOF improved overall performance. The volumetric Taco performed comparably to the Animotus' extension DOF.

  1. Intraluminal ultrasound guidance of transverse laser coronary atherectomy

    Science.gov (United States)

    Aretz, H. Thomas; Martinelli, Michael A.; LeDet, Earl G.; Sedlacek, Tomas; Hatch, G. F.; Gregg, Richard E.

    1990-07-01

    A coronary laser atherectomy system combining laser delivery and ultrasonic imaging capability is described. The system is being developed by Intra-Sonix, Inc. to treat severe stenoses. The imaging system provides the clinician with the guidance needed to remove substantial plaque without perforation. The ultrasound transducers and laser optics are mounted in a small (less than 4 F), flexible catheter, that is deliverable over a standard guidewire (0.016 inch). The laser and ultrasound beams are directed at the artery wall to permit debulking of lesions and ultrasonic depth profiling of the tissue structure throughout the thickness of the artery. This allows the physician to determine the level of therapy to be applied and to monitor the plaque removal as the therapy progresses. The precise location of the ultrasound and laser beams in the artery is determined by a navigation system. Navigation data are processed electronically in conjunction with ultrasound data to produce real-time cross-sectional and longitudinal images of the artery wall at selected locations, which are updated as the catheter progresses through the vessel lumen. Results of in vitro tests on human atherosclerotic arteries and early in vivo experiments in a canine-human xenograft model showing image construction and radial laser delivery are discussed.

  2. First clinical experience with extended planning and navigation in an interventional MRI unit; Erste klinische Erfahrungen mit einer erweiterten Eingriffsplanung und Navigation am interventionellen MRT

    Energy Technology Data Exchange (ETDEWEB)

    Moche, M.; Schneider, J.P.; Schulz, T.; Voerkel, C.; Kahn, T.; Busse, H. [Klinik und Poliklinik fuer Diagnostische Radiologie, Universitaetsklinikum Leipzig (Germany); Schmitgen, A.; Bublat, M. [Fraunhofer-Inst. fuer Angewandte Informationstechnik, St. Augustin (Germany); Trantakis, C. [Klinik und Poliklinik fuer Neurochirurgie, Universitaetsklinikum Leipzig (Germany); Bennek, J. [Klinik und Poliklinik fuer Kinderchirurgie, Univ. Leipzig (Germany)

    2004-07-01

    Purpose: To present an advanced concept for patient-based navigation and to report on our first clinical experience with interventions in the cranium, of soft-tissue structures (breast, liver) and in the musculoskeletal system. Materials and Methods: A PC-based navigation system was integrated into an existing interventional MRI environment. Intraoperatively acquired 3D data were used for interventional planning. The information content of these reference data was increased by integration of additional image modalities (e. g., fMRI, CT) and by color display of areas with early contrast media enhancement. Within 18 months, the system was used in 123 patients undergoing interventions in different anatomic regions (brain: 64, paranasal sinus: 9, breast: 20, liver: 17, bone: 9, muscle: 4). The mean duration of 64 brain interventions was compared that of 36 procedures using the scanner's standard navigation. Results: In contrast with the continuous scanning mode of the MR system (0.25 fps), the higher quality as well as the real time display (4 fps) of the MR images reconstructed from the 3D reference data allowed adequate hand-eye coordination. With our system, patient movement and tissue shifts could be immediately detected intraoperatively, and, in contrast to the standard procedure, navigation safely resumed after updating the reference data. The navigation system was characterized by good stability, efficient system integration and easy usability. Despite additional working steps still to be optimized, the duration of the image-guided brain tumor resections was not significantly longer. (orig.) [German] Ziel: Vorstellung eines erweiterten Konzepts zur patientenbasierten Navigation sowie erste klinische Bewertung der durchgefuehrten Massnahmen im Kopf, Weichteil- und muskuloskeletalen Bereich. Material und Methode: Ein PC-basiertes Navigationssystem wurde in eine vorhandene interventionelle MRT-Umgebung integriert. Intraoperativ akquirierte 3-D

  3. The X-43A Hyper-X Mach 7 Flight 2 Guidance, Navigation, and Control Overview and Flight Test Results

    Science.gov (United States)

    Bahm, Catherine; Baumann, Ethan; Martin, John; Bose, David; Beck, Roger E.; Strovers, Brian

    2005-01-01

    The objective of the Hyper-X program was to flight demonstrate an airframe-integrated hypersonic vehicle. On March 27, 2004, the Hyper-X program team successfully conducted flight 2 and achieved all of the research objectives. The Hyper-X research vehicle successfully separated from the Hyper-X launch vehicle and achieved the desired engine test conditions before the experiment began. The research vehicle rejected the disturbances caused by the cowl door opening and the fuel turning on and off and maintained the engine test conditions throughout the experiment. After the engine test was complete, the vehicle recovered and descended along a trajectory while performing research maneuvers. The last data acquired showed that the vehicle maintained control to the water. This report will provide an overview of the research vehicle guidance and control systems and the performance of the vehicle during the separation event and engine test. The research maneuvers were performed to collect data for aerodynamics and flight controls research. This report also will provide an overview of the flight controls related research and results.

  4. Benefits of Combined GPS/GLONASS with Low-Cost MEMS IMUs for Vehicular Urban Navigation

    Directory of Open Access Journals (Sweden)

    Giovanni Pugliano

    2012-04-01

    Full Text Available The integration of Global Navigation Satellite Systems (GNSS with Inertial Navigation Systems (INS has been very actively researched for many years due to the complementary nature of the two systems. In particular, during the last few years the integration with micro-electromechanical system (MEMS inertial measurement units (IMUs has been investigated. In fact, recent advances in MEMS technology have made possible the development of a new generation of low cost inertial sensors characterized by small size and light weight, which represents an attractive option for mass-market applications such as vehicular and pedestrian navigation. However, whereas there has been much interest in the integration of GPS with a MEMS-based INS, few research studies have been conducted on expanding this application to the revitalized GLONASS system. This paper looks at the benefits of adding GLONASS to existing GPS/INS(MEMS systems using loose and tight integration strategies. The relative benefits of various constraints are also assessed. Results show that when satellite visibility is poor (approximately 50% solution availability the benefits of GLONASS are only seen with tight integration algorithms. For more benign environments, a loosely coupled GPS/GLONASS/INS system offers performance comparable to that of a tightly coupled GPS/INS system, but with reduced complexity and development time.

  5. Benefits of combined GPS/GLONASS with low-cost MEMS IMUs for vehicular urban navigation.

    Science.gov (United States)

    Angrisano, Antonio; Petovello, Mark; Pugliano, Giovanni

    2012-01-01

    The integration of Global Navigation Satellite Systems (GNSS) with Inertial Navigation Systems (INS) has been very actively researched for many years due to the complementary nature of the two systems. In particular, during the last few years the integration with micro-electromechanical system (MEMS) inertial measurement units (IMUs) has been investigated. In fact, recent advances in MEMS technology have made possible the development of a new generation of low cost inertial sensors characterized by small size and light weight, which represents an attractive option for mass-market applications such as vehicular and pedestrian navigation. However, whereas there has been much interest in the integration of GPS with a MEMS-based INS, few research studies have been conducted on expanding this application to the revitalized GLONASS system. This paper looks at the benefits of adding GLONASS to existing GPS/INS(MEMS) systems using loose and tight integration strategies. The relative benefits of various constraints are also assessed. Results show that when satellite visibility is poor (approximately 50% solution availability) the benefits of GLONASS are only seen with tight integration algorithms. For more benign environments, a loosely coupled GPS/GLONASS/INS system offers performance comparable to that of a tightly coupled GPS/INS system, but with reduced complexity and development time.

  6. Development of a real time imaging-based guidance system of magnetic nanoparticles for targeted drug delivery

    International Nuclear Information System (INIS)

    Zhang, Xingming; Le, Tuan-Anh; Yoon, Jungwon

    2017-01-01

    Targeted drug delivery using magnetic nanoparticles is an efficient technique as molecules can be directed toward specific tissues inside a human body. For the first time, we implemented a real-time imaging-based guidance system of nanoparticles using untethered electro-magnetic devices for simultaneous guiding and tracking. In this paper a low-amplitude-excitation-field magnetic particle imaging (MPI) is introduced. Based on this imaging technology, a hybrid system comprised of an electromagnetic actuator and MPI was used to navigate nanoparticles in a non-invasive way. The real-time low-amplitude-excitation-field MPI and electromagnetic actuator of this navigation system are achieved by applying a time-division multiplexing scheme to the coil topology. A one dimensional nanoparticle navigation system was built to demonstrate the feasibility of the proposed approach and it could achieve a 2 Hz navigation update rate with the field gradient of 3.5 T/m during the imaging mode and 8.75 T/m during the actuation mode. Particles with both 90 nm and 5 nm diameters could be successfully manipulated and monitored in a tube through the proposed system, which can significantly enhance targeting efficiency and allow precise analysis in a real drug delivery. - Highlights: • A real-time system comprised of an electromagnetic actuator and a low-amplitude-excitation-field MPI can navigate magnetic nanoparticles. • The imaging scheme is feasible to enlarge field of view size. • The proposed navigation system can be cost efficient, compact, and optimized for targeting of the nanoparticles.

  7. Development of a real time imaging-based guidance system of magnetic nanoparticles for targeted drug delivery

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Xingming [School of Naval Architecture and Ocean Engineering, Harbin Institute of Technology at Weihai, Weihai, Shandong (China); School of Mechanical and Aerospace Engineering & ReCAPT, Gyeongsang National University, Jinju 660-701 (Korea, Republic of); Le, Tuan-Anh [School of Mechanical and Aerospace Engineering & ReCAPT, Gyeongsang National University, Jinju 660-701 (Korea, Republic of); Yoon, Jungwon, E-mail: jwyoon@gnu.ac.kr [School of Mechanical and Aerospace Engineering & ReCAPT, Gyeongsang National University, Jinju 660-701 (Korea, Republic of)

    2017-04-01

    Targeted drug delivery using magnetic nanoparticles is an efficient technique as molecules can be directed toward specific tissues inside a human body. For the first time, we implemented a real-time imaging-based guidance system of nanoparticles using untethered electro-magnetic devices for simultaneous guiding and tracking. In this paper a low-amplitude-excitation-field magnetic particle imaging (MPI) is introduced. Based on this imaging technology, a hybrid system comprised of an electromagnetic actuator and MPI was used to navigate nanoparticles in a non-invasive way. The real-time low-amplitude-excitation-field MPI and electromagnetic actuator of this navigation system are achieved by applying a time-division multiplexing scheme to the coil topology. A one dimensional nanoparticle navigation system was built to demonstrate the feasibility of the proposed approach and it could achieve a 2 Hz navigation update rate with the field gradient of 3.5 T/m during the imaging mode and 8.75 T/m during the actuation mode. Particles with both 90 nm and 5 nm diameters could be successfully manipulated and monitored in a tube through the proposed system, which can significantly enhance targeting efficiency and allow precise analysis in a real drug delivery. - Highlights: • A real-time system comprised of an electromagnetic actuator and a low-amplitude-excitation-field MPI can navigate magnetic nanoparticles. • The imaging scheme is feasible to enlarge field of view size. • The proposed navigation system can be cost efficient, compact, and optimized for targeting of the nanoparticles.

  8. 33 CFR 2.36 - Navigable waters of the United States, navigable waters, and territorial waters.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Navigable waters of the United States, navigable waters, and territorial waters. 2.36 Section 2.36 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY GENERAL JURISDICTION Jurisdictional Terms § 2.36 Navigable waters...

  9. Evaluation of heading performance with vibrotactile guidance: the benefits of information-movement coupling compared with spatial language.

    Science.gov (United States)

    Faugloire, Elise; Lejeune, Laure

    2014-12-01

    This study quantified the effectiveness of tactile guidance in indicating a direction to turn to and measured its benefits compared to spatial language. The device (CAYLAR), which was composed of 8 vibrators, specified the requested direction by a vibration at the corresponding location around the waist. Twelve participants were tested in normal light and in total darkness with 3 guidance conditions: spatial language, a long tactile rhythm (1 s on/4 s off vibrations) providing a single stimulation before movement, and a short rhythm (200 ms on/200 ms off vibrations) allowing information-movement coupling during body rotation. We measured response time, heading error, and asked participants to rate task easiness, intuitiveness and perceived accuracy for each guidance mode. Accuracy was higher and participants' ratings were more positive with the short tactile mode than with the 2 other modes. Compared to spatial language, tactile guidance, regardless of the vibration rhythm, also allowed faster responses and did not impair accuracy in the absence of vision. These findings quantitatively demonstrate that tactile guidance is particularly effective when it is reciprocally related to movement. We discuss implications of the benefits of perception-action coupling for the design of tactile navigation devices. (PsycINFO Database Record (c) 2014 APA, all rights reserved).

  10. Target Trailing With Safe Navigation With Colregs for Maritime Autonomous Surface Vehicles

    Science.gov (United States)

    Kuwata, Yoshiaki (Inventor); Wolf, Michael T. (Inventor); Zarzhitsky, Dimitri V. (Inventor); Aghazarian, Hrand (Inventor); Huntsberger, Terrance L. (Inventor); Howard, Andrew B. (Inventor)

    2014-01-01

    Systems and methods for operating autonomous waterborne vessels in a safe manner. The systems include hardware for identifying the locations and motions of other vessels, as well as the locations of stationary objects that represent navigation hazards. By applying a computational method that uses a maritime navigation algorithm for avoiding hazards and obeying COLREGS using Velocity Obstacles to the data obtained, the autonomous vessel computes a safe and effective path to be followed in order to accomplish a desired navigational end result, while operating in a manner so as to avoid hazards and to maintain compliance with standard navigational procedures defined by international agreement. The systems and methods have been successfully demonstrated on water with radar and stereo cameras as the perception sensors, and integrated with a higher level planner for trailing a maneuvering target.

  11. A Software Defined Radio Based Airplane Communication Navigation Simulation System

    Science.gov (United States)

    He, L.; Zhong, H. T.; Song, D.

    2018-01-01

    Radio communication and navigation system plays important role in ensuring the safety of civil airplane in flight. Function and performance should be tested before these systems are installed on-board. Conventionally, a set of transmitter and receiver are needed for each system, thus all the equipment occupy a lot of space and are high cost. In this paper, software defined radio technology is applied to design a common hardware communication and navigation ground simulation system, which can host multiple airplane systems with different operating frequency, such as HF, VHF, VOR, ILS, ADF, etc. We use a broadband analog frontend hardware platform, universal software radio peripheral (USRP), to transmit/receive signal of different frequency band. Software is compiled by LabVIEW on computer, which interfaces with USRP through Ethernet, and is responsible for communication and navigation signal processing and system control. An integrated testing system is established to perform functional test and performance verification of the simulation signal, which demonstrate the feasibility of our design. The system is a low-cost and common hardware platform for multiple airplane systems, which provide helpful reference for integrated avionics design.

  12. Test Bed for Safety Assessment of New e-Navigation Systems

    Directory of Open Access Journals (Sweden)

    Axel Hahn

    2014-12-01

    Full Text Available New e-navigation strains require new technologies, new infrastructures and new organizational structures on bridge, on shore as well as in the cloud. Suitable engineering and safety/risk assessment methods facilitate these efforts. Understanding maritime transportation as a sociotechnical system allows the application of system-engineering methods. Formal, simulation based and in situ verification and validation of e-navigation technologies are important methods to obtain system safety and reliability. The modelling and simulation toolset HAGGIS provides methods for system specification and formal risk analysis. It provides a modelling framework for processes, fault trees and generic hazard specification and a physical world and maritime traffic simulation system. HAGGIS is accompanied by the physical test bed LABSKAUS which implements a physical test bed. The test bed provides reference ports and waterways in combination with an experimental Vessel Traffic Services (VTS system and a mobile integrated bridge: This enables in situ experiments for technological evaluation, testing, ground research and demonstration. This paper describes an integrated seamless approach for developing new e-navigation technologies starting with simulation based assessment and ending in physical real world demonstrations

  13. The effect of navigational expertise on wayfinding in new environments.

    Science.gov (United States)

    Woollett, Katherine; Maguire, Eleanor A

    2010-12-01

    Becoming proficient at navigation in urban environments is something that we all aspire to. Here we asked whether being an expert at wayfinding in one environment has any effect on learning new spatial layouts. Licensed London taxi drivers are among the most proficient urban navigators, training for many years to find their way around a complex and irregularly-laid out city. We first tested how well they could learn the layout of an unfamiliar town compared with a group of non-taxi drivers. Second, we investigated how effectively taxi drivers could integrate a new district into their existing spatial representation of London. We found that taxi drivers were significantly better than control participants at executing routes through the new town, and representing it at a map-like survey level. However, the benefits of navigational expertise were not universal. Compared with their performance in the new town, taxi drivers were significantly poorer at learning the layout of a new area that had to be integrated with their existing knowledge of London. We consider reasons for this picture of facilitation and limitation, in particular drawing parallels with how knowledge acquisition occurs in the context of expertise in general.

  14. IClinfMRI Software for Integrating Functional MRI Techniques in Presurgical Mapping and Clinical Studies.

    Science.gov (United States)

    Hsu, Ai-Ling; Hou, Ping; Johnson, Jason M; Wu, Changwei W; Noll, Kyle R; Prabhu, Sujit S; Ferguson, Sherise D; Kumar, Vinodh A; Schomer, Donald F; Hazle, John D; Chen, Jyh-Horng; Liu, Ho-Ling

    2018-01-01

    Task-evoked and resting-state (rs) functional magnetic resonance imaging (fMRI) techniques have been applied to the clinical management of neurological diseases, exemplified by presurgical localization of eloquent cortex, to assist neurosurgeons in maximizing resection while preserving brain functions. In addition, recent studies have recommended incorporating cerebrovascular reactivity (CVR) imaging into clinical fMRI to evaluate the risk of lesion-induced neurovascular uncoupling (NVU). Although each of these imaging techniques possesses its own advantage for presurgical mapping, a specialized clinical software that integrates the three complementary techniques and promptly outputs the analyzed results to radiology and surgical navigation systems in a clinical format is still lacking. We developed the Integrated fMRI for Clinical Research (IClinfMRI) software to facilitate these needs. Beyond the independent processing of task-fMRI, rs-fMRI, and CVR mapping, IClinfMRI encompasses three unique functions: (1) supporting the interactive rs-fMRI mapping while visualizing task-fMRI results (or results from published meta-analysis) as a guidance map, (2) indicating/visualizing the NVU potential on analyzed fMRI maps, and (3) exporting these advanced mapping results in a Digital Imaging and Communications in Medicine (DICOM) format that are ready to export to a picture archiving and communication system (PACS) and a surgical navigation system. In summary, IClinfMRI has the merits of efficiently translating and integrating state-of-the-art imaging techniques for presurgical functional mapping and clinical fMRI studies.

  15. Encke-Beta Predictor for Orion Burn Targeting and Guidance

    Science.gov (United States)

    Robinson, Shane; Scarritt, Sara; Goodman, John L.

    2016-01-01

    The state vector prediction algorithm selected for Orion on-board targeting and guidance is known as the Encke-Beta method. Encke-Beta uses a universal anomaly (beta) as the independent variable, valid for circular, elliptical, parabolic, and hyperbolic orbits. The variable, related to the change in eccentric anomaly, results in integration steps that cover smaller arcs of the trajectory at or near perigee, when velocity is higher. Some burns in the EM-1 and EM-2 mission plans are much longer than burns executed with the Apollo and Space Shuttle vehicles. Burn length, as well as hyperbolic trajectories, has driven the use of the Encke-Beta numerical predictor by the predictor/corrector guidance algorithm in place of legacy analytic thrust and gravity integrals.

  16. A model of ant route navigation driven by scene familiarity.

    Directory of Open Access Journals (Sweden)

    Bart Baddeley

    2012-01-01

    Full Text Available In this paper we propose a model of visually guided route navigation in ants that captures the known properties of real behaviour whilst retaining mechanistic simplicity and thus biological plausibility. For an ant, the coupling of movement and viewing direction means that a familiar view specifies a familiar direction of movement. Since the views experienced along a habitual route will be more familiar, route navigation can be re-cast as a search for familiar views. This search can be performed with a simple scanning routine, a behaviour that ants have been observed to perform. We test this proposed route navigation strategy in simulation, by learning a series of routes through visually cluttered environments consisting of objects that are only distinguishable as silhouettes against the sky. In the first instance we determine view familiarity by exhaustive comparison with the set of views experienced during training. In further experiments we train an artificial neural network to perform familiarity discrimination using the training views. Our results indicate that, not only is the approach successful, but also that the routes that are learnt show many of the characteristics of the routes of desert ants. As such, we believe the model represents the only detailed and complete model of insect route guidance to date. What is more, the model provides a general demonstration that visually guided routes can be produced with parsimonious mechanisms that do not specify when or what to learn, nor separate routes into sequences of waypoints.

  17. Fusion of navigational data in River Information Services

    Science.gov (United States)

    Kazimierski, W.

    2009-04-01

    . Their main advantage over AIS is total independence from tracked target's facilities. For example, wrong indications of ship's GPS would affect AIS accuracy, but wouldn't have any impact on values estimated by radar. In addition to this in many times update rate for AIS data is longer than for radar. Thus, it can be noticed, that efficient tracking system introduced in RIS shall use both AIS receivers (based on satellite derived positions), and independent radar and camera sensors. This will however cause determining at least two different set of information about positions and movement parameters of targets. Doubled or multiplied vectors for single target are unacceptable, due to safety of navigation and traffic management. Hence the need of data fusion in RIS is obvious. The main goal is to develop unambiguous, clear and reliable information about ships' position and movement for all users in the system. Data fusion itself is not a new problem in maritime navigation. There are systems of Integrated Bridge on sea-going ships, which use information coming out from different sources. However the possibilities of integration of navigational information in the aspect of inland navigation, especially in River Information Services, still needs to be thoroughly surveyed. It is quite useful for simplifying the deduction, to introduce two data fusion levels. First of them is being done on board of the vessel. Its aim is to integrate all information coming from different sensors in the so called Integrated Navigational System. The other task of this fusion is to estimate reliable information about other objects based on AIS and radar. The second level is the integration of AIS, radar and closed-circuit television (CCTV) carried out in coastal station in order to determine Tactical and Strategic Traffic Image. The navigational information in RIS itself can be divided into two main groups. The first one is called static data and contains al basic information related to ship itself

  18. Integration of image guidance and rapid prototyping technology in craniofacial surgery.

    Science.gov (United States)

    Bullock, P; Dunaway, D; McGurk, L; Richards, R

    2013-08-01

    This technical note demonstrates the benefits of preoperative planning, involving the use of rapid prototype models and rehearsal of the surgical procedure, using image-guided navigational surgery. Optimum reconstruction of large defects can be achieved with this technique. Copyright © 2013 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  19. 77 FR 42637 - Navigation and Navigable Waters; Technical, Organizational, and Conforming Amendments; Corrections

    Science.gov (United States)

    2012-07-20

    ... DEPARTMENT OF HOMELAND SECURITY Coast Guard 33 CFR Parts 84 and 115 [Docket No. USCG-2012-0306] RIN 1625-AB86 Navigation and Navigable Waters; Technical, Organizational, and Conforming Amendments...), the Coast Guard published a final rule entitled ``Navigation and Navigable Waters; Technical...

  20. Orion's Powered Flight Guidance Burn Options for Near Term Exploration Missions

    Science.gov (United States)

    Fill, Thomas; Goodman, John; Robinson, Shane

    2018-01-01

    NASA's Orion exploration spacecraft will fly more demanding mission profiles than previous NASA human flight spacecraft. Missions currently under development are destined for cislunar space. The EM-1 mission will fly unmanned to a Distant Retrograde Orbit (DRO) around the Moon. EM-2 will fly astronauts on a mission to the lunar vicinity. To fly these missions, Orion requires powered flight guidance that is more sophisticated than the orbital guidance flown on Apollo and the Space Shuttle. Orion's powered flight guidance software contains five burn guidance options. These five options are integrated into an architecture based on a proven shuttle heritage design, with a simple closed-loop guidance strategy. The architecture provides modularity, simplicity, versatility, and adaptability to future, yet-to-be-defined, exploration mission profiles. This paper provides a summary of the executive guidance architecture and details the five burn options to support both the nominal and abort profiles for the EM-1 and EM-2 missions.

  1. MONTE: the next generation of mission design and navigation software

    Science.gov (United States)

    Evans, Scott; Taber, William; Drain, Theodore; Smith, Jonathon; Wu, Hsi-Cheng; Guevara, Michelle; Sunseri, Richard; Evans, James

    2018-03-01

    The Mission analysis, Operations and Navigation Toolkit Environment (MONTE) (Sunseri et al. in NASA Tech Briefs 36(9), 2012) is an astrodynamic toolkit produced by the Mission Design and Navigation Software Group at the Jet Propulsion Laboratory. It provides a single integrated environment for all phases of deep space and Earth orbiting missions. Capabilities include: trajectory optimization and analysis, operational orbit determination, flight path control, and 2D/3D visualization. MONTE is presented to the user as an importable Python language module. This allows a simple but powerful user interface via CLUI or script. In addition, the Python interface allows MONTE to be used seamlessly with other canonical scientific programming tools such as SciPy, NumPy, and Matplotlib. MONTE is the prime operational orbit determination software for all JPL navigated missions.

  2. Navigating Instructional Dialectics: Empirical Exploration of Paradox in Teaching

    Science.gov (United States)

    Thompson, Blair; Rudick, C. Kyle; Kerssen-Griep, Jeff; Golsan, Kathryn

    2018-01-01

    Navigating contradiction represents an integral part of the teaching process. While educational literature has discussed the paradoxes that teachers experience in the classroom, minimal empirical research has analyzed the strategies teachers employ to address these paradoxes. Using relational dialectics as a theoretical framework for understanding…

  3. Image-guided navigation system for placing dental implants.

    Science.gov (United States)

    Casap, Nardy; Wexler, Alon; Lustmann, Joshua

    2004-10-01

    Navigation-guided surgery has recently been introduced into various surgical disciplines, including oral and maxillofacial surgery. Since the advent of dental implants, dental computed tomography (CT) scans have been used as a diagnostic tool for preoperative planning, but not as part of the surgical phase. This article explains the principles of computer-assisted surgery and describes the use of a computer-guided navigation system in dental implantology. The system uses preoperative dental CT scans for planning and as an integral part of the surgical procedure. This system allows continuous intraoperative coordination of the implantation phase with the preoperative plan, optimizing the accuracy of implant surgery. Deviations from the planned location of the implants are minimal. Several cases are discussed.

  4. Blind MuseumTourer: A System for Self-Guided Tours in Museums and Blind Indoor Navigation

    Directory of Open Access Journals (Sweden)

    Apostolos Meliones

    2018-01-01

    Full Text Available Notably valuable efforts have focused on helping people with special needs. In this work, we build upon the experience from the BlindHelper smartphone outdoor pedestrian navigation app and present Blind MuseumTourer, a system for indoor interactive autonomous navigation for blind and visually impaired persons and groups (e.g., pupils, which has primarily addressed blind or visually impaired (BVI accessibility and self-guided tours in museums. A pilot prototype has been developed and is currently under evaluation at the Tactual Museum with the collaboration of the Lighthouse for the Blind of Greece. This paper describes the functionality of the application and evaluates candidate indoor location determination technologies, such as wireless local area network (WLAN and surface-mounted assistive tactile route indications combined with Bluetooth low energy (BLE beacons and inertial dead-reckoning functionality, to come up with a reliable and highly accurate indoor positioning system adopting the latter solution. The developed concepts, including map matching, a key concept for indoor navigation, apply in a similar way to other indoor guidance use cases involving complex indoor places, such as in hospitals, shopping malls, airports, train stations, public and municipality buildings, office buildings, university buildings, hotel resorts, passenger ships, etc. The presented Android application is effectively a Blind IndoorGuide system for accurate and reliable blind indoor navigation.

  5. The use of x-ray pulsar-based navigation method for interplanetary flight

    Science.gov (United States)

    Yang, Bo; Guo, Xingcan; Yang, Yong

    2009-07-01

    As interplanetary missions are increasingly complex, the existing unique mature interplanetary navigation method mainly based on radiometric tracking techniques of Deep Space Network can not meet the rising demands of autonomous real-time navigation. This paper studied the applications for interplanetary flights of a new navigation technology under rapid development-the X-ray pulsar-based navigation for spacecraft (XPNAV), and valued its performance with a computer simulation. The XPNAV is an excellent autonomous real-time navigation method, and can provide comprehensive navigation information, including position, velocity, attitude, attitude rate and time. In the paper the fundamental principles and time transformation of the XPNAV were analyzed, and then the Delta-correction XPNAV blending the vehicles' trajectory dynamics with the pulse time-of-arrival differences at nominal and estimated spacecraft locations within an Unscented Kalman Filter (UKF) was discussed with a background mission of Mars Pathfinder during the heliocentric transferring orbit. The XPNAV has an intractable problem of integer pulse phase cycle ambiguities similar to the GPS carrier phase navigation. This article innovatively proposed the non-ambiguity assumption approach based on an analysis of the search space array method to resolve pulse phase cycle ambiguities between the nominal position and estimated position of the spacecraft. The simulation results show that the search space array method are computationally intensive and require long processing time when the position errors are large, and the non-ambiguity assumption method can solve ambiguity problem quickly and reliably. It is deemed that autonomous real-time integrated navigation system of the XPNAV blending with DSN, celestial navigation, inertial navigation and so on will be the development direction of interplanetary flight navigation system in the future.

  6. Radar and electronic navigation

    CERN Document Server

    Sonnenberg, G J

    2013-01-01

    Radar and Electronic Navigation, Sixth Edition discusses radar in marine navigation, underwater navigational aids, direction finding, the Decca navigator system, and the Omega system. The book also describes the Loran system for position fixing, the navy navigation satellite system, and the global positioning system (GPS). It reviews the principles, operation, presentations, specifications, and uses of radar. It also describes GPS, a real time position-fixing system in three dimensions (longitude, latitude, altitude), plus velocity information with Universal Time Coordinated (UTC). It is accur

  7. 75 FR 61771 - Notice of Public Availability of Navigation and Vessel Inspection Circular (NVIC) 2-10, “Guidance...

    Science.gov (United States)

    2010-10-06

    ... voluntary guidance to vessel owners and operators, salvage and marine firefighting resource providers, and... marine firefighting resources to be identified, contracted for, and capable of responding to incidents up...

  8. True navigation and magnetic maps in spiny lobsters.

    Science.gov (United States)

    Boles, Larry C; Lohmann, Kenneth J

    2003-01-02

    Animals are capable of true navigation if, after displacement to a location where they have never been, they can determine their position relative to a goal without relying on familiar surroundings, cues that emanate from the destination, or information collected during the outward journey. So far, only a few animals, all vertebrates, have been shown to possess true navigation. Those few invertebrates that have been carefully studied return to target areas using path integration, landmark recognition, compass orientation and other mechanisms that cannot compensate for displacements into unfamiliar territory. Here we report, however, that the spiny lobster Panulirus argus oriented reliably towards a capture site when displaced 12-37 km to unfamiliar locations, even when deprived of all known orientation cues en route. Little is known about how lobsters and other animals determine position during true navigation. To test the hypothesis that lobsters derive positional information from the Earth's magnetic field, lobsters were exposed to fields replicating those that exist at specific locations in their environment. Lobsters tested in a field north of the capture site oriented themselves southwards, whereas those tested in a field south of the capture site oriented themselves northwards. These results imply that true navigation in spiny lobsters, and perhaps in other animals, is based on a magnetic map sense.

  9. Guidance and Navigation for Rendezvous and Proximity Operations with a Non-Cooperative Spacecraft at Geosynchronous Orbit

    Science.gov (United States)

    Barbee, Brent William; Carpenter, J. Russell; Heatwole, Scott; Markley, F. Landis; Moreau, Michael; Naasz, Bo J.; VanEepoel, John

    2010-01-01

    The feasibility and benefits of various spacecraft servicing concepts are currently being assessed, and all require that the servicer spacecraft perform rendezvous, proximity, and capture operations with the target spacecraft to be serviced. Many high-value spacecraft, which would be logical targets for servicing from an economic point of view, are located in geosynchronous orbit, a regime in which autonomous rendezvous and capture operations are not commonplace. Furthermore, existing GEO spacecraft were not designed to be serviced. Most do not have cooperative relative navigation sensors or docking features, and some servicing applications, such as de-orbiting of a non-functional spacecraft, entail rendezvous and capture with a spacecraft that may be non-functional or un-controlled. Several of these challenges have been explored via the design of a notional mission in which a nonfunctional satellite in geosynchronous orbit is captured by a servicer spacecraft and boosted into super-synchronous orbit for safe disposal. A strategy for autonomous rendezvous, proximity operations, and capture is developed, and the Orbit Determination Toolbox (ODTBX) is used to perform a relative navigation simulation to assess the feasibility of performing the rendezvous using a combination of angles-only and range measurements. Additionally, a method for designing efficient orbital rendezvous sequences for multiple target spacecraft is utilized to examine the capabilities of a servicer spacecraft to service multiple targets during the course of a single mission.

  10. Sporophytic control of pollen tube growth and guidance in maize

    Science.gov (United States)

    Lausser, Andreas; Kliwer, Irina; Srilunchang, Kanok-orn; Dresselhaus, Thomas

    2010-01-01

    Pollen tube germination, growth, and guidance (progamic phase) culminating in sperm discharge is a multi-stage process including complex interactions between the male gametophyte as well as sporophytic tissues and the female gametophyte (embryo sac), respectively. Inter- and intra-specific crossing barriers in maize and Tripsacum have been studied and a precise description of progamic pollen tube development in maize is reported here. It was found that pollen germination and initial tube growth are rather unspecific, but an early, first crossing barrier was detected before arrival at the transmitting tract. Pollination of maize silks with Tripsacum pollen and incompatible pollination of Ga1s/Ga1s-maize silks with ga1-maize pollen revealed another two incompatibility barriers, namely transmitting tract mistargeting and insufficient growth support. Attraction and growth support by the transmitting tract seem to play key roles for progamic pollen tube growth. After leaving transmitting tracts, pollen tubes have to navigate across the ovule in the ovular cavity. Pollination of an embryo sac-less maize RNAi-line allowed the role of the female gametophyte for pollen tube guidance to be determined in maize. It was found that female gametophyte controlled guidance is restricted to a small region around the micropyle, approximately 50–100 μm in diameter. This area is comparable to the area of influence of previously described ZmEA1-based short-range female gametophyte signalling. In conclusion, the progamic phase is almost completely under sporophytic control in maize. PMID:19926683

  11. Differential GNSS and Vision-Based Tracking to Improve Navigation Performance in Cooperative Multi-UAV Systems

    Directory of Open Access Journals (Sweden)

    Amedeo Rodi Vetrella

    2016-12-01

    Full Text Available Autonomous navigation of micro-UAVs is typically based on the integration of low cost Global Navigation Satellite System (GNSS receivers and Micro-Electro-Mechanical Systems (MEMS-based inertial and magnetic sensors to stabilize and control the flight. The resulting navigation performance in terms of position and attitude accuracy may not suffice for other mission needs, such as the ones relevant to fine sensor pointing. In this framework, this paper presents a cooperative UAV navigation algorithm that allows a chief vehicle, equipped with inertial and magnetic sensors, a Global Positioning System (GPS receiver, and a vision system, to improve its navigation performance (in real time or in the post processing phase exploiting formation flying deputy vehicles equipped with GPS receivers. The focus is set on outdoor environments and the key concept is to exploit differential GPS among vehicles and vision-based tracking (DGPS/Vision to build a virtual additional navigation sensor whose information is then integrated in a sensor fusion algorithm based on an Extended Kalman Filter. The developed concept and processing architecture are described, with a focus on DGPS/Vision attitude determination algorithm. Performance assessment is carried out on the basis of both numerical simulations and flight tests. In the latter ones, navigation estimates derived from the DGPS/Vision approach are compared with those provided by the onboard autopilot system of a customized quadrotor. The analysis shows the potential of the developed approach, mainly deriving from the possibility to exploit magnetic- and inertial-independent accurate attitude information.

  12. Using Inertial Sensors in Smartphones for Curriculum Experiments of Inertial Navigation Technology

    Directory of Open Access Journals (Sweden)

    Xiaoji Niu

    2015-03-01

    Full Text Available Inertial technology has been used in a wide range of applications such as guidance, navigation, and motion tracking. However, there are few undergraduate courses that focus on the inertial technology. Traditional inertial navigation systems (INS and relevant testing facilities are expensive and complicated in operation, which makes it inconvenient and risky to perform teaching experiments with such systems. To solve this issue, this paper proposes the idea of using smartphones, which are ubiquitous and commonly contain off-the-shelf inertial sensors, as the experimental devices. A series of curriculum experiments are designed, including the Allan variance test, the calibration test, the initial leveling test and the drift feature test. These experiments are well-selected and can be implemented simply with the smartphones and without any other specialized tools. The curriculum syllabus was designed and tentatively carried out on 14 undergraduate students with a science and engineering background. Feedback from the students show that the curriculum can help them gain a comprehensive understanding of the inertial technology such as calibration and modeling of the sensor errors, determination of the device attitude and accumulation of the sensor errors in the navigation algorithm. The use of inertial sensors in smartphones provides the students the first-hand experiences and intuitive feelings about the function of inertial sensors. Moreover, it can motivate students to utilize ubiquitous low-cost sensors in their future research.

  13. Integrated Spacecraft Navigation and Communication Using Radio, Optical, and X-rays, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — This program proposes to design and evaluate novel technology of X-ray navigation for augmentation and increased capability of high data-rate spacecraft...

  14. An exploration of the patient navigator role: perspectives of younger women with breast cancer.

    Science.gov (United States)

    Pedersen, Allison E; Hack, Thomas F; McClement, Susan E; Taylor-Brown, Jill

    2014-01-01

    To delineate the role of the oncology patient navigator, drawing from the experiences and descriptions of younger women with breast cancer. Interpretive, descriptive, qualitative research design. Participants' homes, researcher's home, and via telephone, all in Winnipeg, Manitoba, Canada. 12 women aged 50 years or younger who were diagnosed with breast cancer within the last three years. Face-to-face semistructured interviews explored patient experiences with the cancer care system, including problems encountered, unmet needs, and opinions about the functions of the patient navigator role. The audio-recorded interviews were transcribed and data were broken down and inductively coded into four categories. Constant comparative techniques also were used during analysis. The role of the oncology patient navigator included two facets: "Processual facets," with the subthemes assigned to me at diagnosis, managing the connection, mapping the process, practical support, and quarterbacking my entire journey; and "Personal qualities: The essentials," with the subthemes empathetic care tenor, knowing the cancer system, and understanding the medical side of breast cancer. Despite the tremendous effort directed toward enhancing care for younger women undergoing treatment for breast cancer, gaps continue to exist. Younger women with breast cancer require a care approach providing ongoing dialogue, teaching, and emotional support from the point of diagnosis through treatment, including transitions of care within the oncology setting and back to their primary care practitioner. Oncology nurse navigators are well positioned to provide patients with anticipatory guidance from diagnosis to the end of treatment.

  15. Ethics of clinician communication in a changing communication landscape: guidance from professional societies.

    Science.gov (United States)

    Gollust, Sarah E; Dwyer, Anne M

    2013-12-01

    Cancer experts engage in public communication whenever they promote their research or practice, respond to media inquiries, or use social media. In a changing communication landscape characterized by new technologies and heightened attention to cancer controversies, these activities may pose ethical challenges. This study was designed to evaluate existing resources to help clinicians navigate their public communication activities. We conducted a systematic, qualitative content analysis of codes of ethics, policy statements, and similar documents disseminated by professional medical and nursing societies for their members. We examined these documents for four types of content related to public communication: communication via traditional media; communication via social media; other communication to the public, policy, and legal spheres; and nonspecific language regarding public communication. We identified 46 documents from 23 professional societies for analysis. Five societies had language about traditional news media communication, five had guidance about social media, 11 had guidance about other communication domains, and 15 societies offered general language about public communication. The limited existing guidance focused on ethical issues related to patients (such as privacy violations) or clinicians (such as accuracy and professional boundaries), with less attention to population or policy impact of communication. Cancer-related professional societies might consider establishing more specific guidance for clinicians concerning their communication activities in light of changes to the communication landscape. Additional research is warranted to understand the extent to which clinicians face ethical challenges in public communication.

  16. Navigation capabilities of mid-cost GNSS/INS vs. smartphone analysis and comparison in urban navigation scenarios

    OpenAIRE

    Martí, Luis; García, Jesús; Molina, José M.

    2014-01-01

    Proceedings of: 17th International Conference on Information Fusion (FUSION 2014): Salamanca, Spain 7-10 July 2014. High accuracy navigation usually require expensive sensors and/or its careful integration into a complex and finely tuned system. Smartphones pack a high number of sensors in a portable format, becoming a source of low-quality information with a high heterogeneity and redundancy. This work compares pure GNSS/INS capabilities on both types of platform, and discuss the weakness...

  17. An improved particle filter and its application to an INS/GPS integrated navigation system in a serious noisy scenario

    International Nuclear Information System (INIS)

    Wang, Xuemei; Ni, Wenbo

    2016-01-01

    For loosely coupled INS/GPS integrated navigation systems with low-cost and low-accuracy microelectromechanical device inertial sensors, in order to obtain enough accuracy, a full-state nonlinear dynamic model rather than a linearized error model is much more preferable. Particle filters are particularly for nonlinear and non-Gaussian situations, but typical bootstrap particle filters (BPFs) and some improved particle filters (IPFs) such as auxiliary particle filters (APFs) and Gaussian particle filters (GPFs) cannot solve the mismatch between the importance function and the likelihood function very well. The predicted particles propagated through inertial navigation equations cannot be scattered with certainty within the effective range of current observation when there are large drift errors of the inertial sensors. Therefore, the current observation cannot play the correction role well and these particle filters are invalid to some extent. The proposed IPF firstly estimates the corresponding state bias errors according to the current observation and then corrects the bias errors of the predicted particles before determining the weights and resampling the particles. Simulations and practical experiments both show that the proposed IPF can effectively solve the mismatch between the importance function and the likelihood function of a BPF and compensate the accumulated errors of INSs very well. It has great robustness in a serious noisy scenario. (paper)

  18. 76 FR 59142 - Guidance for Industry on Reproductive and Developmental Toxicities-Integrating Study Results To...

    Science.gov (United States)

    2011-09-23

    ... of study results to assess concerns about human reproductive and developmental toxicities. It does... assist that office in processing your requests. See the SUPPLEMENTARY INFORMATION section for electronic access to the guidance document. Submit electronic comments on the guidance to http://www.regulations.gov...

  19. Navigation concepts for magnetic resonance imaging-guided musculoskeletal interventions.

    Science.gov (United States)

    Busse, Harald; Kahn, Thomas; Moche, Michael

    2011-08-01

    Image-guided musculoskeletal (MSK) interventions are a widely used alternative to open surgical procedures for various pathological findings in different body regions. They traditionally involve one of the established x-ray imaging techniques (radiography, fluoroscopy, computed tomography) or ultrasound scanning. Over the last decades, magnetic resonance imaging (MRI) has evolved into one of the most powerful diagnostic tools for nearly the whole body and has therefore been increasingly considered for interventional guidance as well.The strength of MRI for MSK applications is a combination of well-known general advantages, such as multiplanar and functional imaging capabilities, wide choice of tissue contrasts, and absence of ionizing radiation, as well as a number of MSK-specific factors, for example, the excellent depiction of soft-tissue tumors, nonosteolytic bone changes, and bone marrow lesions. On the downside, the magnetic resonance-compatible equipment needed, restricted space in the magnet, longer imaging times, and the more complex workflow have so far limited the number of MSK procedures under MRI guidance.Navigation solutions are generally a natural extension of any interventional imaging system, in particular, because powerful hardware and software for image processing have become routinely available. They help to identify proper access paths, provide accurate feedback on the instrument positions, facilitate the workflow in an MRI environment, and ultimately contribute to procedural safety and success.The purposes of this work were to describe some basic concepts and devices for MRI guidance of MSK procedures and to discuss technical and clinical achievements and challenges for some selected implementations.

  20. An Integrated Assessment of Progress in Robotic Perception and Semantic Navigation

    Science.gov (United States)

    2015-09-01

    Navigation by Craig Lennon, Barry Bodt, Marshal Childers, Jean Oh, Arne Suppe, Luis Navarro-Serment, Robert Dean, Terrence Keegan , Chip Diberardino...Directorate, ARL Jean Oh, Arne Suppe, and Luis Navarro-Serment National Robotics Engineering Center, Pittsburgh, PA Robert Dean, Terrence Keegan ...AUTHOR(S) Craig Lennon, Barry Bodt, Marshal Childers, Jean Oh, Arne Suppe, Luis Navarro-Serment, Robert Dean, Terrence Keegan , Chip Diberardino

  1. Survey of computer vision technology for UVA navigation

    Science.gov (United States)

    Xie, Bo; Fan, Xiang; Li, Sijian

    2017-11-01

    Navigation based on computer version technology, which has the characteristics of strong independence, high precision and is not susceptible to electrical interference, has attracted more and more attention in the filed of UAV navigation research. Early navigation project based on computer version technology mainly applied to autonomous ground robot. In recent years, the visual navigation system is widely applied to unmanned machine, deep space detector and underwater robot. That further stimulate the research of integrated navigation algorithm based on computer version technology. In China, with many types of UAV development and two lunar exploration, the three phase of the project started, there has been significant progress in the study of visual navigation. The paper expounds the development of navigation based on computer version technology in the filed of UAV navigation research and draw a conclusion that visual navigation is mainly applied to three aspects as follows.(1) Acquisition of UAV navigation parameters. The parameters, including UAV attitude, position and velocity information could be got according to the relationship between the images from sensors and carrier's attitude, the relationship between instant matching images and the reference images and the relationship between carrier's velocity and characteristics of sequential images.(2) Autonomous obstacle avoidance. There are many ways to achieve obstacle avoidance in UAV navigation. The methods based on computer version technology ,including feature matching, template matching, image frames and so on, are mainly introduced. (3) The target tracking, positioning. Using the obtained images, UAV position is calculated by using optical flow method, MeanShift algorithm, CamShift algorithm, Kalman filtering and particle filter algotithm. The paper expounds three kinds of mainstream visual system. (1) High speed visual system. It uses parallel structure, with which image detection and processing are

  2. GPS/MEMS IMU/Microprocessor Board for Navigation

    Science.gov (United States)

    Gender, Thomas K.; Chow, James; Ott, William E.

    2009-01-01

    A miniaturized instrumentation package comprising a (1) Global Positioning System (GPS) receiver, (2) an inertial measurement unit (IMU) consisting largely of surface-micromachined sensors of the microelectromechanical systems (MEMS) type, and (3) a microprocessor, all residing on a single circuit board, is part of the navigation system of a compact robotic spacecraft intended to be released from a larger spacecraft [e.g., the International Space Station (ISS)] for exterior visual inspection of the larger spacecraft. Variants of the package may also be useful in terrestrial collision-detection and -avoidance applications. The navigation solution obtained by integrating the IMU outputs is fed back to a correlator in the GPS receiver to aid in tracking GPS signals. The raw GPS and IMU data are blended in a Kalman filter to obtain an optimal navigation solution, which can be supplemented by range and velocity data obtained by use of (l) a stereoscopic pair of electronic cameras aboard the robotic spacecraft and/or (2) a laser dynamic range imager aboard the ISS. The novelty of the package lies mostly in those aspects of the design of the MEMS IMU that pertain to controlling mechanical resonances and stabilizing scale factors and biases.

  3. Guidance on future art commissioning.

    Science.gov (United States)

    2009-05-01

    Delegates at Building Better Healthcare's recent "National Patient Environment and the Arts Conference 2009" in London heard how national public arts think tank ixia has appointed Bristol-based arts and wellbeing development agency Willis Newson to write "concise and convincing guidance" on commissioning art for new healthcare facilities. A key message, during a joint presentation, was that integrating artwork into hospitals and other healthcare premises requires the earliest possible consideration to reap the maximum rewards.

  4. Sensors integration for smartphone navigation: performances and future challenges

    Science.gov (United States)

    Aicardi, I.; Dabove, P.; Lingua, A.; Piras, M.

    2014-08-01

    Nowadays the modern smartphones include several sensors which are usually adopted in geomatic application, as digital camera, GNSS (Global Navigation Satellite System) receivers, inertial platform, RFID and Wi-Fi systems. In this paper the authors would like to testing the performances of internal sensors (Inertial Measurement Unit, IMU) of three modern smartphones (Samsung GalaxyS4, Samsung GalaxyS5 and iPhone4) compared to external mass-market IMU platform in order to verify their accuracy levels, in terms of positioning. Moreover, the Image Based Navigation (IBN) approach is also investigated: this approach can be very useful in hard-urban environment or for indoor positioning, as alternative to GNSS positioning. IBN allows to obtain a sub-metrical accuracy, but a special database of georeferenced images (Image DataBase, IDB) is needed, moreover it is necessary to use dedicated algorithm to resizing the images which are collected by smartphone, in order to share it with the server where is stored the IDB. Moreover, it is necessary to characterize smartphone camera lens in terms of focal length and lens distortions. The authors have developed an innovative method with respect to those available today, which has been tested in a covered area, adopting a special support where all sensors under testing have been installed. Geomatic instrument have been used to define the reference trajectory, with purpose to compare this one, with the path obtained with IBN solution. First results leads to have an horizontal and vertical accuracies better than 60 cm, respect to the reference trajectories. IBN method, sensors, test and result will be described in the paper.

  5. Visual navigation in insects: coupling of egocentric and geocentric information

    Science.gov (United States)

    Wehner; Michel; Antonsen

    1996-01-01

    Social hymenopterans such as bees and ants are central-place foragers; they regularly depart from and return to fixed positions in their environment. In returning to the starting point of their foraging excursion or to any other point, they could resort to two fundamentally different ways of navigation by using either egocentric or geocentric systems of reference. In the first case, they would rely on information continuously collected en route (path integration, dead reckoning), i.e. integrate all angles steered and all distances covered into a mean home vector. In the second case, they are expected, at least by some authors, to use a map-based system of navigation, i.e. to obtain positional information by virtue of the spatial position they occupy within a larger environmental framework. In bees and ants, path integration employing a skylight compass is the predominant mechanism of navigation, but geocentred landmark-based information is used as well. This information is obtained while the animal is dead-reckoning and, hence, added to the vector course. For example, the image of the horizon skyline surrounding the nest entrance is retinotopically stored while the animal approaches the goal along its vector course. As shown in desert ants (genus Cataglyphis), there is neither interocular nor intraocular transfer of landmark information. Furthermore, this retinotopically fixed, and hence egocentred, neural snapshot is linked to an external (geocentred) system of reference. In this way, geocentred information might more and more complement and potentially even supersede the egocentred information provided by the path-integration system. In competition experiments, however, Cataglyphis never frees itself of its homeward-bound vector - its safety-line, so to speak - by which it is always linked to home. Vector information can also be transferred to a longer-lasting (higher-order) memory. There is no need to invoke the concept of the mental analogue of a topographic

  6. Targeting Accuracy, Procedure Times and User Experience of 240 Experimental MRI Biopsies Guided by a Clinical Add-On Navigation System.

    Science.gov (United States)

    Busse, Harald; Riedel, Tim; Garnov, Nikita; Thörmer, Gregor; Kahn, Thomas; Moche, Michael

    2015-01-01

    MRI is of great clinical utility for the guidance of special diagnostic and therapeutic interventions. The majority of such procedures are performed iteratively ("in-and-out") in standard, closed-bore MRI systems with control imaging inside the bore and needle adjustments outside the bore. The fundamental limitations of such an approach have led to the development of various assistance techniques, from simple guidance tools to advanced navigation systems. The purpose of this work was to thoroughly assess the targeting accuracy, workflow and usability of a clinical add-on navigation solution on 240 simulated biopsies by different medical operators. Navigation relied on a virtual 3D MRI scene with real-time overlay of the optically tracked biopsy needle. Smart reference markers on a freely adjustable arm ensured proper registration. Twenty-four operators - attending (AR) and resident radiologists (RR) as well as medical students (MS) - performed well-controlled biopsies of 10 embedded model targets (mean diameter: 8.5 mm, insertion depths: 17-76 mm). Targeting accuracy, procedure times and 13 Likert scores on system performance were determined (strong agreement: 5.0). Differences in diagnostic success rates (AR: 93%, RR: 88%, MS: 81%) were not significant. In contrast, between-group differences in biopsy times (AR: 4:15, RR: 4:40, MS: 5:06 min:sec) differed significantly (p<0.01). Mean overall rating was 4.2. The average operator would use the system again (4.8) and stated that the outcome justifies the extra effort (4.4). Lowest agreement was reported for the robustness against external perturbations (2.8). The described combination of optical tracking technology with an automatic MRI registration appears to be sufficiently accurate for instrument guidance in a standard (closed-bore) MRI environment. High targeting accuracy and usability was demonstrated on a relatively large number of procedures and operators. Between groups with different expertise there were

  7. Targeting Accuracy, Procedure Times and User Experience of 240 Experimental MRI Biopsies Guided by a Clinical Add-On Navigation System.

    Directory of Open Access Journals (Sweden)

    Harald Busse

    Full Text Available MRI is of great clinical utility for the guidance of special diagnostic and therapeutic interventions. The majority of such procedures are performed iteratively ("in-and-out" in standard, closed-bore MRI systems with control imaging inside the bore and needle adjustments outside the bore. The fundamental limitations of such an approach have led to the development of various assistance techniques, from simple guidance tools to advanced navigation systems. The purpose of this work was to thoroughly assess the targeting accuracy, workflow and usability of a clinical add-on navigation solution on 240 simulated biopsies by different medical operators.Navigation relied on a virtual 3D MRI scene with real-time overlay of the optically tracked biopsy needle. Smart reference markers on a freely adjustable arm ensured proper registration. Twenty-four operators - attending (AR and resident radiologists (RR as well as medical students (MS - performed well-controlled biopsies of 10 embedded model targets (mean diameter: 8.5 mm, insertion depths: 17-76 mm. Targeting accuracy, procedure times and 13 Likert scores on system performance were determined (strong agreement: 5.0.Differences in diagnostic success rates (AR: 93%, RR: 88%, MS: 81% were not significant. In contrast, between-group differences in biopsy times (AR: 4:15, RR: 4:40, MS: 5:06 min:sec differed significantly (p<0.01. Mean overall rating was 4.2. The average operator would use the system again (4.8 and stated that the outcome justifies the extra effort (4.4. Lowest agreement was reported for the robustness against external perturbations (2.8.The described combination of optical tracking technology with an automatic MRI registration appears to be sufficiently accurate for instrument guidance in a standard (closed-bore MRI environment. High targeting accuracy and usability was demonstrated on a relatively large number of procedures and operators. Between groups with different expertise there were

  8. Computer-assisted navigational surgery enhances safety in dental implantology.

    Science.gov (United States)

    Ng, F C; Ho, K H; Wexler, A

    2005-06-01

    Dental implants are increasingly used to restore missing dentition. These titanium implants are surgically installed in the edentulous alveolar ridge and allowed to osteointegrate with the bone during the healing phase. After osseo-integration, the implant is loaded with a prosthesis to replace the missing tooth. Conventional implant treatment planning uses study models, wax-ups and panoramic x-rays to prefabricate surgical stent to guide the preparation of the implant site. The drilling into the alveolar ridge is invariably a "blind" procedure as the part of the drill in bone is not visible. Stereotactic systems were first introduced into neurosurgery in 1986. Since then, computer-assisted navigational technology has brought major advances to neuro-, midface and orthopaedic surgeries, and more recently, to implant placement. This paper illustrates the use of real-time computer-guided navigational technology in enhancing safety in implant surgical procedures. Real-time computer-guided navigational technology enhances accuracy and precision of the surgical procedure, minimises complications and facilitates surgery in challenging anatomical locations.

  9. Determination of UAV position using high accuracy navigation platform

    Directory of Open Access Journals (Sweden)

    Ireneusz Kubicki

    2016-07-01

    Full Text Available The choice of navigation system for mini UAV is very important because of its application and exploitation, particularly when the installed on it a synthetic aperture radar requires highly precise information about an object’s position. The presented exemplary solution of such a system draws attention to the possible problems associated with the use of appropriate technology, sensors, and devices or with a complete navigation system. The position and spatial orientation errors of the measurement platform influence on the obtained SAR imaging. Both, turbulences and maneuvers performed during flight cause the changes in the position of the airborne object resulting in deterioration or lack of images from SAR. Consequently, it is necessary to perform operations for reducing or eliminating the impact of the sensors’ errors on the UAV position accuracy. You need to look for compromise solutions between newer better technologies and in the field of software. Keywords: navigation systems, unmanned aerial vehicles, sensors integration

  10. Juvenile Osprey Navigation during Trans-Oceanic Migration.

    Directory of Open Access Journals (Sweden)

    Travis W Horton

    Full Text Available To compensate for drift, an animal migrating through air or sea must be able to navigate. Although some species of bird, fish, insect, mammal, and reptile are capable of drift compensation, our understanding of the spatial reference frame, and associated coordinate space, in which these navigational behaviors occur remains limited. Using high resolution satellite-monitored GPS track data, we show that juvenile ospreys (Pandion haliaetus are capable of non-stop constant course movements over open ocean spanning distances in excess of 1500 km despite the perturbing effects of winds and the lack of obvious landmarks. These results are best explained by extreme navigational precision in an exogenous spatio-temporal reference frame, such as positional orientation relative to Earth's magnetic field and pacing relative to an exogenous mechanism of keeping time. Given the age (<1 year-old of these birds and knowledge of their hatching site locations, we were able to transform Enhanced Magnetic Model coordinate locations such that the origin of the magnetic coordinate space corresponded with each bird's nest. Our analyses show that trans-oceanic juvenile osprey movements are consistent with bicoordinate positional orientation in transformed magnetic coordinate or geographic space. Through integration of movement and meteorological data, we propose a new theoretical framework, chord and clock navigation, capable of explaining the precise spatial orientation and temporal pacing performed by juvenile ospreys during their long-distance migrations over open ocean.

  11. GUIDANCE FOR NUCLEAR POWER PLANT CONTROL ROOM AND HUMAN-SYSTEM INTERFACE MODERNIZATION

    International Nuclear Information System (INIS)

    Naser, J.; Morris, G.

    2004-01-01

    Several nuclear power plants in the United States are starting instrumentation and control (I and C) modernization programs using digital equipment to address obsolescence issues and the need to improve plant performance while maintaining high levels of safety. As an integral part of the I and C modernization program at a nuclear power plant, the control room and other human-system interfaces (HSIs) are also being modernized. To support safe and effective operation, it is critical to plan, design, implement, train for, operate, and maintain the control room and HSI changes to take advantage of human cognitive processing abilities. A project, jointly funded by the Electric Power Research Institute (EPRI) and the United States Department of Energy (DOE) under the Nuclear Energy Plant Optimization (NEPO) Program, is developing guidance for specifying and designing control rooms, remote shut-down panels, HSIs etc. The guidance is intended for application by utilities and suppliers of control room and HSI modernization. The guidance will facilitate specification, design, implementation, operations, maintenance, training, and licensing activities. This guidance will be used to reduce the likelihood of human errors and licensing risk, to gain maximum benefit of implemented technology, and to increase performance. The guidance is of five types. The first is planning guidance to help a utility develop its plant-specific control room operating concepts, its plant-specific endpoint vision for the control room, its migration path to achieve that endpoint vision, and its regulatory, licensing, and human factors program plans. The second is process guidance for general HSI design and integration, human factors engineering analyses, verification and validation, in-service monitoring processes, etc. The third is detailed human factors engineering guidance for control room and HSI technical areas. The fourth is guidance for licensing. The fifth is guidance for special topics

  12. Space Launch Systems Block 1B Preliminary Navigation System Design

    Science.gov (United States)

    Oliver, T. Emerson; Park, Thomas; Anzalone, Evan; Smith, Austin; Strickland, Dennis; Patrick, Sean

    2018-01-01

    NASA is currently building the Space Launch Systems (SLS) Block 1 launch vehicle for the Exploration Mission 1 (EM-1) test flight. In parallel, NASA is also designing the Block 1B launch vehicle. The Block 1B vehicle is an evolution of the Block 1 vehicle and extends the capability of the NASA launch vehicle. This evolution replaces the Interim Cryogenic Propulsive Stage (ICPS) with the Exploration Upper Stage (EUS). As the vehicle evolves to provide greater lift capability, increased robustness for manned missions, and the capability to execute more demanding missions so must the SLS Integrated Navigation System evolved to support those missions. This paper describes the preliminary navigation systems design for the SLS Block 1B vehicle. The evolution of the navigation hard-ware and algorithms from an inertial-only navigation system for Block 1 ascent flight to a tightly coupled GPS-aided inertial navigation system for Block 1B is described. The Block 1 GN&C system has been designed to meet a LEO insertion target with a specified accuracy. The Block 1B vehicle navigation system is de-signed to support the Block 1 LEO target accuracy as well as trans-lunar or trans-planetary injection accuracy. Additionally, the Block 1B vehicle is designed to support human exploration and thus is designed to minimize the probability of Loss of Crew (LOC) through high-quality inertial instruments and robust algorithm design, including Fault Detection, Isolation, and Recovery (FDIR) logic.

  13. Real-time image guidance in laparoscopic liver surgery

    DEFF Research Database (Denmark)

    Kenngott, Hannes G.; Wagner, Martin; Gondan, Matthias

    2014-01-01

    Background: Laparoscopic liver surgery is particularly challenging owing to restricted access, risk of bleeding and lack of haptic feedback. Navigation systems have the potential to improve information on the exact position of intrahepatic tumors, and thus facilitate oncological resection....... This study aims to evaluate the feasibility of a commercially available augmented reality (AR) guidance system employing intraoperative robotic C-arm cone-beam computed tomography (CBCT) for laparoscopic liver surgery. Methods: A human liver-like phantom with sixteen target fiducials was used to evaluate...... the Syngo iPilot® AR system. Subsequently, the system was used for the laparoscopic resection of a hepatocellular carcinoma in segment 7 of a 50-year-old male patient. Results: In the phantom experiment the AR system showed a mean target registration error of 0.96 mm ± 0.52 mm with a maximum error of 2...

  14. 33 CFR 66.05-100 - Designation of navigable waters as State waters for private aids to navigation.

    Science.gov (United States)

    2010-07-01

    ... as State waters for private aids to navigation. 66.05-100 Section 66.05-100 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-100 Designation of navigable waters as State waters for private aids to...

  15. COBALT CoOperative Blending of Autonomous Landing Technology

    Science.gov (United States)

    Carson, John M. III; Restrepo, Carolina I.; Robertson, Edward A.; Seubert, Carl R.; Amzajerdian, Farzin

    2016-01-01

    COBALT is a terrestrial test platform for development and maturation of GN&C (Guidance, Navigation and Control) technologies for PL&HA (Precision Landing and Hazard Avoidance). The project is developing a third generation, Langley Navigation Doppler Lidar (NDL) for ultra-precise velocity and range measurements, which will be integrated and tested with the JPL Lander Vision System (LVS) for Terrain Relative Navigation (TRN) position estimates. These technologies together provide navigation that enables controlled precision landing. The COBALT hardware will be integrated in 2017 into the GN&C subsystem of the Xodiac rocket-propulsive Vertical Test Bed (VTB) developed by Masten Space Systems (MSS), and two terrestrial flight campaigns will be conducted: one open-loop (i.e., passive) and one closed-loop (i.e., active).

  16. Navigation outside of the box: what the lab can learn from the field and what the field can learn from the lab.

    Science.gov (United States)

    Jacobs, Lucia F; Menzel, Randolf

    2014-01-01

    Space is continuous. But the communities of researchers that study the cognitive map in non-humans are strangely divided, with debate over its existence found among behaviorists but not neuroscientists. To reconcile this and other debates within the field of navigation, we return to the concept of the parallel map theory, derived from data on hippocampal function in laboratory rodents. Here the cognitive map is redefined as the integrated map, which is a construction of dual mechanisms, one based on directional cues (bearing map) and the other on positional cues (sketch map). We propose that the dual navigational mechanisms of pigeons, the navigational map and the familiar area map, could be homologous to these mammalian parallel maps; this has implications for both research paradigms. Moreover, this has implications for the lab. To create a bearing map (and hence integrated map) from extended cues requires self-movement over a large enough space to sample and model these cues at a high resolution. Thus a navigator must be able to move freely to map extended cues; only then should the weighted hierarchy of available navigation mechanisms shift in favor of the integrated map. Because of the paucity of extended cues in the lab, the flexible solutions allowed by the integrated map should be rare, despite abundant neurophysiological evidence for the existence of the machinery needed to encode and map extended cues through voluntary movement. Not only do animals need to map extended cues but they must also have sufficient information processing capacity. This may require a specific ontogeny, in which the navigator's nervous system is exposed to naturally complex spatial contingencies, a circumstance that occurs rarely, if ever, in the lab. For example, free-ranging, flying animals must process more extended cues than walking animals and for this reason alone, the integrated map strategy may be found more reliably in some species. By taking concepts from ethology and the

  17. Navigation Problems in Blind-to-Blind Pedestrians Tele-assistance Navigation

    OpenAIRE

    Balata , Jan; Mikovec , Zdenek; Maly , Ivo

    2015-01-01

    International audience; We raise a question whether it is possible to build a large-scale navigation system for blind pedestrians where a blind person navigates another blind person remotely by mobile phone. We have conducted an experiment, in which we observed blind people navigating each other in a city center in 19 sessions. We focused on problems in the navigator’s attempts to direct the traveler to the destination. We observed 96 problems in total, classified them on the basis of the typ...

  18. Using the framework of corporate culture in “mergers” to support the development of a cultural basis for integrative medicine – guidance for building an integrative medicine department or service

    Directory of Open Access Journals (Sweden)

    Witt CM

    2015-01-01

    Full Text Available Claudia M Witt,1–3 Marion Pérard,2 Brian Berman,3,4 Susan Berman,4 Timothy C Birdsall,5 Horst Defren,6 Sherko Kümmel,7 Gary Deng,8 Gustav Dobos,9 Atje Drexler,10 Christine Holmberg,2 Markus Horneber,11 Robert Jütte,9 Lori Knutson,12 Christopher Kummer,13 Susanne Volpers,14 David Schweiger15 1University Hospital Zurich, Institute for Complementary and Integrative Medicine, Zurich, Switzerland; 2Institute for Social Medicine, Epidemiology and Health Economics, Charité-Universitätsmedizin, Berlin, Germany; 3University of Maryland School of Medicine, Center for Integrative Medicine, Baltimore, Maryland, USA; 4The Institute for Integrative Health, Baltimore, USA; 5Cancer Treatment Centers of America, Goodyear, Arizona, USA, 6Kliniken Essen Mitte, Evang, Huyssen-Stiftung/Knappschaft GmbH Patientenmanagement, Essen, Germany; 7Department of Senology, Breast Center, Kliniken Essen-Mitte, Evang. Huyssens Stiftung, Knappschaft GmbH, Essen, Germany; 8Memorial Sloan-Kettering Cancer Center, New York, USA; 9Department of Internal and Integrative Medicine, Kliniken Essen-Mitte, Academic Teaching Hospital of the University of Duisburg-Essen, Germany; 10Robert Bosch Foundation GmbH, Stuttgart, Germany; 11Department of Internal Medicine, Division of Oncology and Hematology, Paracelsus Medical University, Klinikum Nürnberg, Germany; 12Integrative Healthcare Solutions, Minneapolis, Minnesota, USA; 13Institute of Mergers, Acquisitions and Alliances (IMAA, Zurich, Switzerland; 14Frauenselbsthilfe nach Krebs, Bonn, Germany; 15Schweiger, Schweiger & Associates, Hilton Head Island, South Carolina, USA Background: An increasing number of clinics offer complementary or integrative medicine services; however, clear guidance about how complementary medicine could be successfully and efficiently integrated into conventional health care settings is still lacking. Combining conventional and complementary medicine into integrative medicine can be regarded as a kind of

  19. Guidance and Control of Position and Attitude for Rendezvous and Dock/Berthing with a Noncooperative/Target Spacecraft

    Directory of Open Access Journals (Sweden)

    Gilberto Arantes

    2014-01-01

    Full Text Available Noncooperative target spacecrafts are those assets in orbit that cannot convey any information about their states (position, attitude, and velocities or facilitate rendezvous and docking/berthing (RVD/B process. Designing a guidance, navigation, and control (GNC module for the chaser in a RVD/B mission with noncooperative target should be inevitably solved for on-orbit servicing technologies. The proximity operations and the guidance for achieving rendezvous problems are addressed in this paper. The out-of-plane maneuvers of proximity operations are explored with distinct subphases, including a chaser far approach in the target’s orbit to the first hold point and a closer approach to the final berthing location. Accordingly, guidance solutions are chosen for each subphase from the standard Hill based Closhessy-Willtshire (CW solution, elliptical fly-around, and Glideslope algorithms. The control is based on a linear quadratic regulator approach (LQR. At the final berthing location, attitude tracker based on a proportional derivative (PD form is tested to synchronize the chaser and target attitudes. The paper analyzes the performance of both controllers in terms of the tracking ability and the robustness. Finally, it prescribes any restrictions that may be imposed on the guidance during any subphase which can help to improve the controllers tracking ability.

  20. Absolute Navigation Performance of the Orion Exploration Fight Test 1

    Science.gov (United States)

    Zanetti, Renato; Holt, Greg; Gay, Robert; D'Souza, Christopher; Sud, Jastesh

    2016-01-01

    Launched in December 2014 atop a Delta IV Heavy from the Kennedy Space Center, the Orion vehicle's Exploration Flight Test-1 (EFT-1) successfully completed the objective to stress the system by placing the un-crewed vehicle on a high-energy parabolic trajectory replicating conditions similar to those that would be experienced when returning from an asteroid or a lunar mission. Unique challenges associated with designing the navigation system for EFT-1 are presented with an emphasis on how redundancy and robustness influenced the architecture. Two Inertial Measurement Units (IMUs), one GPS receiver and three barometric altimeters (BALTs) comprise the navigation sensor suite. The sensor data is multiplexed using conventional integration techniques and the state estimate is refined by the GPS pseudorange and deltarange measurements in an Extended Kalman Filter (EKF) that employs UDU factorization. The performance of the navigation system during flight is presented to substantiate the design.

  1. 78 FR 68101 - Environmental Issues Associated With New Reactors and Specific Environmental Guidance for...

    Science.gov (United States)

    2013-11-13

    ... New Reactors and Specific Environmental Guidance for Integral Pressurized Water Reactors Reviews... Environmental Issues Associated with New Reactors'' and draft ISG ESP/ COL-ISG-027, ``Interim Staff Guidance on...://www.regulations.gov and search for Docket ID NRC-2013-0212 for ESP/COL- ISG-026 or NRC-2013-0211 for...

  2. Ground Simulation of an Autonomous Satellite Rendezvous and Tracking System Using Dual Robotic Systems

    Science.gov (United States)

    Trube, Matthew J.; Hyslop, Andrew M.; Carignan, Craig R.; Easley, Joseph W.

    2012-01-01

    A hardware-in-the-loop ground system was developed for simulating a robotic servicer spacecraft tracking a target satellite at short range. A relative navigation sensor package "Argon" is mounted on the end-effector of a Fanuc 430 manipulator, which functions as the base platform of the robotic spacecraft servicer. Machine vision algorithms estimate the pose of the target spacecraft, mounted on a Rotopod R-2000 platform, relay the solution to a simulation of the servicer spacecraft running in "Freespace", which performs guidance, navigation and control functions, integrates dynamics, and issues motion commands to a Fanuc platform controller so that it tracks the simulated servicer spacecraft. Results will be reviewed for several satellite motion scenarios at different ranges. Key words: robotics, satellite, servicing, guidance, navigation, tracking, control, docking.

  3. Bridging IMO e-Navigation Policy and Offshore Oil and Gas Operations through Geospatial Standards

    Directory of Open Access Journals (Sweden)

    Filipe Modesto Da Rocha

    2016-04-01

    Full Text Available In offshore industry activities, the suitable onboard provision of assets location and geospatial marine information during operations is essential. Currently, most companies use its own data structures, resulting in incompatibility between processes. In order to promote the data exchange, oil and gas industry associations have pursued initiatives to standardize spatial information. In turn, the IMO - International Maritime Organization - started the implementation of e-Navigation policy, which is the standardization of technologies and protocols applied to maritime information and navigation. This paper shows relationship and integration points between maritime activities of oil and gas industry and e-Navigation technologies and processes, highlighting geospatial information. This paper also preludes out an initiative for a suitable product specification for the offshore oil and gas industry, compliant with e-Navigation and IHO S-100 international standards.

  4. High-Payoff Space Transportation Design Approach with a Technology Integration Strategy

    Science.gov (United States)

    McCleskey, C. M.; Rhodes, R. E.; Chen, T.; Robinson, J.

    2011-01-01

    A general architectural design sequence is described to create a highly efficient, operable, and supportable design that achieves an affordable, repeatable, and sustainable transportation function. The paper covers the following aspects of this approach in more detail: (1) vehicle architectural concept considerations (including important strategies for greater reusability); (2) vehicle element propulsion system packaging considerations; (3) vehicle element functional definition; (4) external ground servicing and access considerations; and, (5) simplified guidance, navigation, flight control and avionics communications considerations. Additionally, a technology integration strategy is forwarded that includes: (a) ground and flight test prior to production commitments; (b) parallel stage propellant storage, such as concentric-nested tanks; (c) high thrust, LOX-rich, LOX-cooled first stage earth-to-orbit main engine; (d) non-toxic, day-of-launch-loaded propellants for upper stages and in-space propulsion; (e) electric propulsion and aero stage control.

  5. Intraoperative navigation-guided resection of anomalous transverse processes in patients with Bertolotti's syndrome.

    Science.gov (United States)

    Babu, Harish; Lagman, Carlito; Kim, Terrence T; Grode, Marshall; Johnson, J Patrick; Drazin, Doniel

    2017-01-01

    Bertolotti's syndrome is characterized by enlargement of the transverse process at the most caudal lumbar vertebra with a pseudoarticulation between the transverse process and sacral ala. Here, we describe the use of intraoperative three-dimensional image-guided navigation in the resection of anomalous transverse processes in two patients with Bertolotti's syndrome. Two patients diagnosed with Bertolotti's syndrome who had undergone the above-mentioned procedure were identified. The patients were 17- and 38-years-old, and presented with severe, chronic low back pain that was resistant to conservative treatment. Imaging revealed lumbosacral transitional vertebrae at the level of L5-S1, which was consistent with Bertolotti's syndrome. Injections of the pseudoarticulations resulted in only temporary symptomatic relief. Thus, the patients subsequently underwent O-arm neuronavigational resection of the bony defects. Both patients experienced immediate pain resolution (documented on the postoperative notes) and remained asymptomatic 1 year later. Intraoperative three-dimensional imaging and navigation guidance facilitated the resection of anomalous transverse processes in two patients with Bertolotti's syndrome. Excellent outcomes were achieved in both patients.

  6. EnEx-RANGE - Robust autonomous Acoustic Navigation in Glacial icE

    Science.gov (United States)

    Heinen, Dirk; Eliseev, Dmitry; Henke, Christoph; Jeschke, Sabina; Linder, Peter; Reuter, Sebastian; Schönitz, Sebastian; Scholz, Franziska; Weinstock, Lars Steffen; Wickmann, Stefan; Wiebusch, Christopher; Zierke, Simon

    2017-03-01

    Within the Enceladus Explorer Initiative of the DLR Space Administration navigation technologies for a future space mission are in development. Those technologies are the basis for the search for extraterrestrial life on the Saturn moon Enceladus. An autonomous melting probe, the EnEx probe, aims to extract a liquid sample from a water reservoir below the icy crust. A first EnEx probe was developed and demonstrated in a terrestrial scenario at the Bloodfalls, Taylor Glacier, Antarctica in November 2014. To enable navigation in glacier ice two acoustic systems were integrated into the probe in addition to conventional navigation technologies. The first acoustic system determines the position of the probe during the run based on propagation times of acoustic signals from emitters at reference positions at the glacier surface to receivers in the probe. The second system provides information about the forefield of the probe. It is based on sonographic principles with phased array technology integrated in the probe's melting head. Information about obstacles or sampling regions in the probe's forefield can be acquired. The development of both systems is now continued in the project EnEx-RANGE. The emitters of the localization system are replaced by a network of intelligent acoustic enabled melting probes. These localize each other by means of acoustic signals and create the reference system for the EnEx probe. This presentation includes the discussion of the intelligent acoustic network, the acoustic navigation systems of the EnEx probe and results of terrestrial tests.

  7. Indoor wayfinding and navigation

    CERN Document Server

    2015-01-01

    Due to the widespread use of navigation systems for wayfinding and navigation in the outdoors, researchers have devoted their efforts in recent years to designing navigation systems that can be used indoors. This book is a comprehensive guide to designing and building indoor wayfinding and navigation systems. It covers all types of feasible sensors (for example, Wi-Fi, A-GPS), discussing the level of accuracy, the types of map data needed, the data sources, and the techniques for providing routes and directions within structures.

  8. Control algorithms for autonomous robot navigation

    International Nuclear Information System (INIS)

    Jorgensen, C.C.

    1985-01-01

    This paper examines control algorithm requirements for autonomous robot navigation outside laboratory environments. Three aspects of navigation are considered: navigation control in explored terrain, environment interactions with robot sensors, and navigation control in unanticipated situations. Major navigation methods are presented and relevance of traditional human learning theory is discussed. A new navigation technique linking graph theory and incidental learning is introduced

  9. Impact of trained oncology financial navigators on patient out-of-pocket spending.

    Science.gov (United States)

    Yezefski, Todd; Steelquist, Jordan; Watabayashi, Kate; Sherman, Dan; Shankaran, Veena

    2018-03-01

    Patients with cancer often face financial hardships, including loss of productivity, high out-of-pocket (OOP) costs, depletion of savings, and bankruptcy. By providing financial guidance and assistance through specially trained navigators, hospitals and cancer care clinics may be able mitigate the financial burdens to patients and also minimize financial losses for the treating institutions. Financial navigators at 4 hospitals were trained through The NaVectis Group, an organization that provides training to healthcare staff to increase patient access to care and assist with OOP expenses. Data regarding financial assistance and hospital revenue were collected after instituting these programs. Amount and type of assistance (free medication, new insurance enrollment, premium/co-pay assistance) were determined annually for all qualifying patients at the participating hospitals. Of 11,186 new patients with cancer seen across the 4 participating hospitals between 2012 and 2016, 3572 (32%) qualified for financial assistance. They obtained $39 million in total financial assistance, averaging $3.5 million per year in the 11 years under observation. Patients saved an average of $33,265 annually on medication, $12,256 through enrollment in insurance plans, $35,294 with premium assistance, and $3076 with co-pay assistance. The 4 hospitals were able to avoid write-offs and save on charity care by an average of $2.1 million per year. Providing financial navigation training to staff at hospitals and cancer centers can significantly benefit patients through decreased OOP expenditures and also mitigate financial losses for healthcare institutions.

  10. Image-guided Navigation of Single-element Focused Ultrasound Transducer

    Science.gov (United States)

    Kim, Hyungmin; Chiu, Alan; Park, Shinsuk; Yoo, Seung-Schik

    2014-01-01

    The spatial specificity and controllability of focused ultrasound (FUS), in addition to its ability to modify the excitability of neural tissue, allows for the selective and reversible neuromodulation of the brain function, with great potential in neurotherapeutics. Intra-operative magnetic resonance imaging (MRI) guidance (in short, MRg) has limitations due to its complicated examination logistics, such as fixation through skull screws to mount the stereotactic frame, simultaneous sonication in the MRI environment, and restrictions in choosing MR-compatible materials. In order to overcome these limitations, an image-guidance system based on optical tracking and pre-operative imaging data is developed, separating the imaging acquisition for guidance and sonication procedure for treatment. Techniques to define the local coordinates of the focal point of sonication are presented. First, mechanical calibration detects the concentric rotational motion of a rigid-body optical tracker, attached to a straight rod mimicking the sonication path, pivoted at the virtual FUS focus. The spatial error presented in the mechanical calibration was compensated further by MRI-based calibration, which estimates the spatial offset between the navigated focal point and the ground-truth location of the sonication focus obtained from a temperature-sensitive MR sequence. MRI-based calibration offered a significant decrease in spatial errors (1.9±0.8 mm; 57% reduction) compared to the mechanical calibration method alone (4.4±0.9 mm). Using the presented method, pulse-mode FUS was applied to the motor area of the rat brain, and successfully stimulated the motor cortex. The presented techniques can be readily adapted for the transcranial application of FUS to intact human brain. PMID:25232203

  11. Miniature Inertial and Augmentation Sensors for Integrated Inertial/GPS Based Navigation Applications

    Science.gov (United States)

    2010-03-01

    Magnetometer (Ref [23]) Until miniature atomic magnetometers transition from laboratory demonstration units to a mass produced product, fluxgate ...and/or magnetoresistive designs are a better suited magnetometer technology for a miniature navigation system. Figure 8 below shows the basic fluxgate ...is required to resolve magnetic field orientation. Fig 8. Fluxgate Magnetometer Schematic The PNI Sensor Corporation (Santa Rosa, CA

  12. A Leapfrog Navigation System

    Science.gov (United States)

    Opshaug, Guttorm Ringstad

    There are times and places where conventional navigation systems, such as the Global Positioning System (GPS), are unavailable due to anything from temporary signal occultations to lack of navigation system infrastructure altogether. The goal of the Leapfrog Navigation System (LNS) is to provide localized positioning services for such cases. The concept behind leapfrog navigation is to advance a group of navigation units teamwise into an area of interest. In a practical 2-D case, leapfrogging assumes known initial positions of at least two currently stationary navigation units. Two or more mobile units can then start to advance into the area of interest. The positions of the mobiles are constantly being calculated based on cross-range distance measurements to the stationary units, as well as cross-ranges among the mobiles themselves. At some point the mobile units stop, and the stationary units are released to move. This second team of units (now mobile) can then overtake the first team (now stationary) and travel even further towards the common goal of the group. Since there always is one stationary team, the position of any unit can be referenced back to the initial positions. Thus, LNS provides absolute positioning. I developed navigation algorithms needed to solve leapfrog positions based on cross-range measurements. I used statistical tools to predict how position errors would grow as a function of navigation unit geometry, cross-range measurement accuracy and previous position errors. Using this knowledge I predicted that a 4-unit Leapfrog Navigation System using 100 m baselines and 200 m leap distances could travel almost 15 km before accumulating absolute position errors of 10 m (1sigma). Finally, I built a prototype leapfrog navigation system using 4 GPS transceiver ranging units. I placed the 4 units in the vertices a 10m x 10m square, and leapfrogged the group 20 meters forwards, and then back again (40 m total travel). Average horizontal RMS position

  13. Demonstration of coherent Doppler lidar for navigation in GPS-denied environments

    Science.gov (United States)

    Amzajerdian, Farzin; Hines, Glenn D.; Pierrottet, Diego F.; Barnes, Bruce W.; Petway, Larry B.; Carson, John M.

    2017-05-01

    A coherent Doppler lidar has been developed to address NASA's need for a high-performance, compact, and cost-effective velocity and altitude sensor onboard its landing vehicles. Future robotic and manned missions to solar system bodies require precise ground-relative velocity vector and altitude data to execute complex descent maneuvers and safe, soft landing at a pre-designated site. This lidar sensor, referred to as a Navigation Doppler Lidar (NDL), meets the required performance of the landing missions while complying with vehicle size, mass, and power constraints. Operating from up to four kilometers altitude, the NDL obtains velocity and range precision measurements reaching 2 cm/sec and 2 meters, respectively, dominated by the vehicle motion. Terrestrial aerial vehicles will also benefit from NDL data products as enhancement or replacement to GPS systems when GPS is unavailable or redundancy is needed. The NDL offers a viable option to aircraft navigation in areas where the GPS signal can be blocked or jammed by intentional or unintentional interference. The NDL transmits three laser beams at different pointing angles toward the ground to measure range and velocity along each beam using a frequency modulated continuous wave (FMCW) technique. The three line-of-sight measurements are then combined in order to determine the three components of the vehicle velocity vector and its altitude relative to the ground. This paper describes the performance and capabilities that the NDL demonstrated through extensive ground tests, helicopter flight tests, and onboard an autonomous rocket-powered test vehicle while operating in closedloop with a guidance, navigation, and control (GN and C) system.

  14. Cost consideration in the clinical guidance documents of physician specialty societies in the United States.

    Science.gov (United States)

    Schwartz, Jennifer A T; Pearson, Steven D

    2013-06-24

    Despite increasing concerns regarding the cost of health care, the consideration of costs in the development of clinical guidance documents by physician specialty societies has received little analysis. To evaluate the approach to consideration of cost in publicly available clinical guidance documents and methodological statements produced between 2008 and 2012 by the 30 largest US physician specialty societies. Qualitative document review. Whether costs are considered in clinical guidance development, mechanism of cost consideration, and the way that cost issues were used in support of specific clinical practice recommendations. Methodological statements for clinical guidance documents indicated that 17 of 30 physician societies (57%) explicitly integrated costs, 4 (13%) implicitly considered costs, 3 (10%) intentionally excluded costs, and 6 (20%) made no mention. Of the 17 societies that explicitly integrated costs, 9 (53%) consistently used a formal system in which the strength of recommendation was influenced in part by costs, whereas 8 (47%) were inconsistent in their approach or failed to mention the exact mechanism for considering costs. Among the 138 specific recommendations in these guidance documents that included cost as part of the rationale, the most common form of recommendation (50 [36%]) encouraged the use of a specific medical service because of equal effectiveness and lower cost. Slightly more than half of the largest US physician societies explicitly consider costs in developing their clinical guidance documents; among these, approximately half use an explicit mechanism for integrating costs into the strength of recommendations. Many societies remain vague in their approach. Physician specialty societies should demonstrate greater transparency and rigor in their approach to cost consideration in documents meant to influence care decisions.

  15. Intra-operative ultrasound-based augmented reality guidance for laparoscopic surgery.

    Science.gov (United States)

    Singla, Rohit; Edgcumbe, Philip; Pratt, Philip; Nguan, Christopher; Rohling, Robert

    2017-10-01

    In laparoscopic surgery, the surgeon must operate with a limited field of view and reduced depth perception. This makes spatial understanding of critical structures difficult, such as an endophytic tumour in a partial nephrectomy. Such tumours yield a high complication rate of 47%, and excising them increases the risk of cutting into the kidney's collecting system. To overcome these challenges, an augmented reality guidance system is proposed. Using intra-operative ultrasound, a single navigation aid, and surgical instrument tracking, four augmentations of guidance information are provided during tumour excision. Qualitative and quantitative system benefits are measured in simulated robot-assisted partial nephrectomies. Robot-to-camera calibration achieved a total registration error of 1.0 ± 0.4 mm while the total system error is 2.5 ± 0.5 mm. The system significantly reduced healthy tissue excised from an average (±standard deviation) of 30.6 ± 5.5 to 17.5 ± 2.4 cm 3 ( p < 0.05) and reduced the depth from the tumor underside to cut from an average (±standard deviation) of 10.2 ± 4.1 to 3.3 ± 2.3 mm ( p < 0.05). Further evaluation is required in vivo, but the system has promising potential to reduce the amount of healthy parenchymal tissue excised.

  16. Optimal motion planning using navigation measure

    Science.gov (United States)

    Vaidya, Umesh

    2018-05-01

    We introduce navigation measure as a new tool to solve the motion planning problem in the presence of static obstacles. Existence of navigation measure guarantees collision-free convergence at the final destination set beginning with almost every initial condition with respect to the Lebesgue measure. Navigation measure can be viewed as a dual to the navigation function. While the navigation function has its minimum at the final destination set and peaks at the obstacle set, navigation measure takes the maximum value at the destination set and is zero at the obstacle set. A linear programming formalism is proposed for the construction of navigation measure. Set-oriented numerical methods are utilised to obtain finite dimensional approximation of this navigation measure. Application of the proposed navigation measure-based theoretical and computational framework is demonstrated for a motion planning problem in a complex fluid flow.

  17. Career guidance in communities

    DEFF Research Database (Denmark)

    Thomsen, Rie

    for the development of a critically reflexive career guidance practice. The considerations are organised around seven elements. 1. Creating opportunity, structure and access 2. Entering a community and increasing visibility 3. Providing guidance in communities 4. Exploring potentials in guidance situations 5...... in career guidance practices as well as in the lives of the people in the communities. This paper falls into two parts: The first part considers the collective as the starting point for the development of meaningful career guidance activities. Based on previous research on career guidance in communities......The aim of this paper is to inspire practitioners and professionals to leave their offices to bring career guidance into communities that might not identify with career guidance in the first instance. By making the effort to engage with communities, practitioners may bring about a critical change...

  18. Hybrid optical navigation by crater detection for lunar pin-point landing: trajectories from helicopter flight tests

    Science.gov (United States)

    Trigo, Guilherme F.; Maass, Bolko; Krüger, Hans; Theil, Stephan

    2018-01-01

    Accurate autonomous navigation capabilities are essential for future lunar robotic landing missions with a pin-point landing requirement, since in the absence of direct line of sight to ground control during critical approach and landing phases, or when facing long signal delays the herein before mentioned capability is needed to establish a guidance solution to reach the landing site reliably. This paper focuses on the processing and evaluation of data collected from flight tests that consisted of scaled descent scenarios where the unmanned helicopter of approximately 85 kg approached a landing site from altitudes of 50 m down to 1 m for a downrange distance of 200 m. Printed crater targets were distributed along the ground track and their detection provided earth-fixed measurements. The Crater Navigation (CNav) algorithm used to detect and match the crater targets is an unmodified method used for real lunar imagery. We analyze the absolute position and attitude solutions of CNav obtained and recorded during these flight tests, and investigate the attainable quality of vehicle pose estimation using both CNav and measurements from a tactical-grade inertial measurement unit. The navigation filter proposed for this end corrects and calibrates the high-rate inertial propagation with the less frequent crater navigation fixes through a closed-loop, loosely coupled hybrid setup. Finally, the attainable accuracy of the fused solution is evaluated by comparison with the on-board ground-truth solution of a dual-antenna high-grade GNSS receiver. It is shown that the CNav is an enabler for building autonomous navigation systems with high quality and suitability for exploration mission scenarios.

  19. Review of Research On Guidance for Recovery from Pitch Axis Upsets

    Science.gov (United States)

    Harrison, Stephanie J.

    2016-01-01

    A literature review was conducted to identify past efforts in providing control guidance for aircraft upset recovery including stall recovery. Because guidance is integrally linked to the intended function of aircraft attitude awareness and upset recognition, it is difficult, if not impossible, to consider these issues separately. This literature review covered the aspects of instrumentation and display symbologies for attitude awareness, aircraft upset recognition, upset and stall alerting, and control guidance. Many different forms of symbology have been investigated including, but not limited to, pitch scale depictions, attitude indicator icons, horizon symbology, attitude recovery arrows, and pitch trim indicators. Past research on different visual and alerting strategies that provide advisories, cautions, and warnings to pilots before entering an unusual attitude (UA) are also discussed. Finally, potential control guidance for recovery from upset or unusual attitudes, including approach-to-stall and stall conditions, are reviewed. Recommendations for future research are made.

  20. Report 3: Guidance document on practices to model and implement Extreme Weather hazards in extended PSA

    International Nuclear Information System (INIS)

    Alzbutas, R.; Ostapchuk, S.; Borysiewicz, M.; Decker, K.; Kumar, Manorma; Haeggstroem, A.; Nitoi, M.; Groudev, P.; Parey, S.; Potempski, S.; Raimond, E.; Siklossy, T.

    2016-01-01

    The goal of this report is to provide guidance on practices to model Extreme Weather hazards and implement them in extended level 1 PSA. This report is a joint deliverable of work package 21 (WP21) and work package 22 (WP22). The general objective of WP21 is to provide guidance on all of the individual hazards selected at the End Users Workshop. This guidance is focusing on extreme weather hazards, namely: extreme wind, extreme temperature and snow pack. Other hazards, however, are considered in cases where they are correlated/ associated with the hazard under discussion. Guidance developed refers to existing guidance whenever possible. As it was recommended by end users this guidance covers questions of developing integrated and/or separated extreme weathers PSA models. (authors)

  1. 77 FR 29458 - Supervisory Guidance on Stress Testing for Banking Organizations With More Than $10 Billion in...

    Science.gov (United States)

    2012-05-17

    ... of risk management, the final guidance provides principles that a banking organization should follow... integrated into overall risk management.\\8\\ The agencies expect such companies would follow the principles... risk management program. The guidance outlines broad principles for a [[Page 29464

  2. Unified Simulation and Analysis Framework for Deep Space Navigation Design

    Science.gov (United States)

    Anzalone, Evan; Chuang, Jason; Olsen, Carrie

    2013-01-01

    As the technology that enables advanced deep space autonomous navigation continues to develop and the requirements for such capability continues to grow, there is a clear need for a modular expandable simulation framework. This tool's purpose is to address multiple measurement and information sources in order to capture system capability. This is needed to analyze the capability of competing navigation systems as well as to develop system requirements, in order to determine its effect on the sizing of the integrated vehicle. The development for such a framework is built upon Model-Based Systems Engineering techniques to capture the architecture of the navigation system and possible state measurements and observations to feed into the simulation implementation structure. These models also allow a common environment for the capture of an increasingly complex operational architecture, involving multiple spacecraft, ground stations, and communication networks. In order to address these architectural developments, a framework of agent-based modules is implemented to capture the independent operations of individual spacecraft as well as the network interactions amongst spacecraft. This paper describes the development of this framework, and the modeling processes used to capture a deep space navigation system. Additionally, a sample implementation describing a concept of network-based navigation utilizing digitally transmitted data packets is described in detail. This developed package shows the capability of the modeling framework, including its modularity, analysis capabilities, and its unification back to the overall system requirements and definition.

  3. Active instrumental guidance in interventional magnetic resonance imaging

    International Nuclear Information System (INIS)

    Wildermuth, S.; Erhart, P.; Leung, D.A.; Goehde, S.; Schoenenberger, A.; Debatin, J.F.

    1998-01-01

    Purpose: An active MR-based guidance system for visualisation of invasive instruments is described. Methods: The principle of MR tracking is based on the integration of a miniaturised coil into the tip of the instrument itself. A phantom experiment was designed to demonstrate the localising accuracy of this technique. In [dition, bicompatibility and warming effects were evaluated. Preliminary intravascular applications that were performed in animal experiments under MR guidance included embolisation, vascular occlusion as well as transjugular intrahepatic punctures. Percutaneous biopsies, cholecystostomies and laparoscopic applications were also evaluated with MR tracking. Results: Phantom experiments confirmed an excellent localisation accuracy of MR tracking compared to conventional r[iography. At a field strength of 0.5 T, the temperature increase remained below 2 C. Results of phantom experiments revealed a potential of significant heating dependent on the sequence parameters employed. MR tracking allowed a robust, simultaneously biplanar visualisation of the instrument tips in real time. Based on MR 'ro[ map' images, various intravascular and percutaneous interventions were successfully performed in vivo under MR guidance. Conclusions: MR tracking is a flexible concept permitting monitoring in the guidance of instruments in an MR environment. Various preliminary in vitro and in vivo experiments demonstrate safety, localisation accuracy and feasibility of this biplanar localisation technique in real time. (orig.) [de

  4. Implementation of a mobile base with evasion of obstacles using ROS navigation

    International Nuclear Information System (INIS)

    Arauz Villegas, Carolina

    2013-01-01

    A mobile base is implemented with evasion of obstacles using ROS Navigation. The simulation of that mobile base is performed with the 2D Stage simulator, firstly; and once understanded the operation of Navigation has proceeded to build the mobile base. The mobile base has had two DC motors, an Asus Xtion sensor, a netbook and a stm32f4-discovery microcontroller. ROS in the netbook was installed and then serial communication over USB was achieved between the netbook and the microcontroller. The microcontroller has received the velocity data sent by move_base of navigation through that communication and sends the odometry data back. A PWM control is implemented for the driving and for the speed of the motors having a control PI for the cycle of work of the same. The encoder interface of the microcontroller was used for the data acquisition of odometry. The communication between ROS and the mobile base was integrated to the navigation, which has allowed to generate mapping, location and move safely from a starting point to a point of arrival sending speed messages. (author) [es

  5. Integration and evaluation of a needle-positioning robot with volumetric microcomputed tomography image guidance for small animal stereotactic interventions

    International Nuclear Information System (INIS)

    Waspe, Adam C.; McErlain, David D.; Pitelka, Vasek; Holdsworth, David W.; Lacefield, James C.; Fenster, Aaron

    2010-01-01

    Purpose: Preclinical research protocols often require insertion of needles to specific targets within small animal brains. To target biologically relevant locations in rodent brains more effectively, a robotic device has been developed that is capable of positioning a needle along oblique trajectories through a single burr hole in the skull under volumetric microcomputed tomography (micro-CT) guidance. Methods: An x-ray compatible stereotactic frame secures the head throughout the procedure using a bite bar, nose clamp, and ear bars. CT-to-robot registration enables structures identified in the image to be mapped to physical coordinates in the brain. Registration is accomplished by injecting a barium sulfate contrast agent as the robot withdraws the needle from predefined points in a phantom. Registration accuracy is affected by the robot-positioning error and is assessed by measuring the surface registration error for the fiducial and target needle tracks (FRE and TRE). This system was demonstrated in situ by injecting 200 μm tungsten beads into rat brains along oblique trajectories through a single burr hole on the top of the skull under micro-CT image guidance. Postintervention micro-CT images of each skull were registered with preintervention high-field magnetic resonance images of the brain to infer the anatomical locations of the beads. Results: Registration using four fiducial needle tracks and one target track produced a FRE and a TRE of 96 and 210 μm, respectively. Evaluation with tissue-mimicking gelatin phantoms showed that locations could be targeted with a mean error of 154±113 μm. Conclusions: The integration of a robotic needle-positioning device with volumetric micro-CT image guidance should increase the accuracy and reduce the invasiveness of stereotactic needle interventions in small animals.

  6. Integration and evaluation of a needle-positioning robot with volumetric microcomputed tomography image guidance for small animal stereotactic interventions

    Energy Technology Data Exchange (ETDEWEB)

    Waspe, Adam C.; McErlain, David D.; Pitelka, Vasek; Holdsworth, David W.; Lacefield, James C.; Fenster, Aaron [Biomedical Engineering Graduate Program and Imaging Research Laboratories, Robarts Research Institute, University of Western Ontario, London, Ontario N6A 5K8 (Canada); Department of Medical Biophysics and Imaging Research Laboratories, Robarts Research Institute, University of Western Ontario, London, Ontario N6A 5K8 (Canada); Department of Physiology and Pharmacology, University of Western Ontario, London, Ontario N6A 5C1 (Canada); Biomedical Engineering Graduate Program, Department of Medical Biophysics, Department of Medical Imaging, Department of Surgery, and Imaging Research Laboratories, Robarts Research Institute, University of Western Ontario, London, Ontario N6A 5K8 (Canada); Biomedical Engineering Graduate Program, Department of Electrical and Computer Engineering, Department of Medical Biophysics, and Imaging Research Laboratories, Robarts Research Institute, University of Western Ontario, London, Ontario N6A 5K8 (Canada); Biomedical Engineering Graduate Program, Department of Medical Biophysics, Department of Medical Imaging, and Imaging Research Laboratories, Robarts Research Institute, University of Western Ontario, London, Ontario N6A 5K8 (Canada)

    2010-04-15

    Purpose: Preclinical research protocols often require insertion of needles to specific targets within small animal brains. To target biologically relevant locations in rodent brains more effectively, a robotic device has been developed that is capable of positioning a needle along oblique trajectories through a single burr hole in the skull under volumetric microcomputed tomography (micro-CT) guidance. Methods: An x-ray compatible stereotactic frame secures the head throughout the procedure using a bite bar, nose clamp, and ear bars. CT-to-robot registration enables structures identified in the image to be mapped to physical coordinates in the brain. Registration is accomplished by injecting a barium sulfate contrast agent as the robot withdraws the needle from predefined points in a phantom. Registration accuracy is affected by the robot-positioning error and is assessed by measuring the surface registration error for the fiducial and target needle tracks (FRE and TRE). This system was demonstrated in situ by injecting 200 {mu}m tungsten beads into rat brains along oblique trajectories through a single burr hole on the top of the skull under micro-CT image guidance. Postintervention micro-CT images of each skull were registered with preintervention high-field magnetic resonance images of the brain to infer the anatomical locations of the beads. Results: Registration using four fiducial needle tracks and one target track produced a FRE and a TRE of 96 and 210 {mu}m, respectively. Evaluation with tissue-mimicking gelatin phantoms showed that locations could be targeted with a mean error of 154{+-}113 {mu}m. Conclusions: The integration of a robotic needle-positioning device with volumetric micro-CT image guidance should increase the accuracy and reduce the invasiveness of stereotactic needle interventions in small animals.

  7. LiDAR Scan Matching Aided Inertial Navigation System in GNSS-Denied Environments.

    Science.gov (United States)

    Tang, Jian; Chen, Yuwei; Niu, Xiaoji; Wang, Li; Chen, Liang; Liu, Jingbin; Shi, Chuang; Hyyppä, Juha

    2015-07-10

    A new scan that matches an aided Inertial Navigation System (INS) with a low-cost LiDAR is proposed as an alternative to GNSS-based navigation systems in GNSS-degraded or -denied environments such as indoor areas, dense forests, or urban canyons. In these areas, INS-based Dead Reckoning (DR) and Simultaneous Localization and Mapping (SLAM) technologies are normally used to estimate positions as separate tools. However, there are critical implementation problems with each standalone system. The drift errors of velocity, position, and heading angles in an INS will accumulate over time, and on-line calibration is a must for sustaining positioning accuracy. SLAM performance is poor in featureless environments where the matching errors can significantly increase. Each standalone positioning method cannot offer a sustainable navigation solution with acceptable accuracy. This paper integrates two complementary technologies-INS and LiDAR SLAM-into one navigation frame with a loosely coupled Extended Kalman Filter (EKF) to use the advantages and overcome the drawbacks of each system to establish a stable long-term navigation process. Static and dynamic field tests were carried out with a self-developed Unmanned Ground Vehicle (UGV) platform-NAVIS. The results prove that the proposed approach can provide positioning accuracy at the centimetre level for long-term operations, even in a featureless indoor environment.

  8. Conceptual Design of Haptic-Feedback Navigation Device for Individuals with Alzheimer's Disease.

    Science.gov (United States)

    Che Me, Rosalam; Biamonti, Alessandro; Mohd Saad, Mohd Rashid

    2015-01-01

    Wayfinding ability in older adults with Alzheimer's disease (AD) is progressively impaired due to ageing and deterioration of cognitive domains. Usually, the sense of direction is deteriorated as visuospatial and spatial cognition are associated with the sensory acuity. Therefore, navigation systems that support only visual interactions may not be appropriate in case of AD. This paper presents a concept of wearable navigation device that integrates the haptic-feedback technology to facilitate the wayfinding of individuals with AD. The system provides the simplest instructions; left/right using haptic signals, as to avoid users' distraction during navigation. The advantages of haptic/tactile modality for wayfinding purpose based on several significant studies are presented. As preliminary assessment, a survey is conducted to understand the potential of this design concept in terms of (1) acceptability, (2) practicality, (3) wearability, and (4) environmental settings. Results indicate that the concept is highly acceptable and commercially implementable. A working prototype will be developed based on the results of the preliminary assessment. Introducing a new method of navigation should be followed by continuous practices for familiarization purpose. Improved navigability allows the good performance of activities of daily living (ADLs) hence maintain the good quality of life in older adults with AD.

  9. Water chemistry guidance in nuclear power plants in Japan

    International Nuclear Information System (INIS)

    Uchida, Shunsuke; Okada, Hidetoshi; Suzuki, Hiroaki; Naitoh, Masanori

    2012-01-01

    Water chemistry plays important roles in safe and reliable plant operation which are very critical for future power rate increases as well as aging plant management. Water chemistry control is required to satisfy the need for improved integrity of target materials, and at the same time it must be optimal for all materials and systems in a plant. Optimal water chemistry can be maintained by expert engineers who are knowledgeable about plant water chemistry, who have sufficient experience with plant operation, and whose knowledge is based on fundamental technologies. One of the latest subjects in the field of water chemistry is achieving suitable technical transfers, in which the achievements and experience with plant water chemistry accumulated by experts are successfully transferred to the next generation of engineers. For this purpose, documents on experience with water chemistry are being compiled as the guidance for water chemistry control and water chemistry standards, e.g., standards for chemical analysis procedures and guidance for water chemistry control procedures. This paper introduces the latest activities in Japan in establishing water chemistry guidance involving water chemistry standards, guidance documents and their supporting documents. (orig.)

  10. Lunar Navigation Architecture Design Considerations

    Science.gov (United States)

    D'Souza, Christopher; Getchius, Joel; Holt, Greg; Moreau, Michael

    2009-01-01

    The NASA Constellation Program is aiming to establish a long-term presence on the lunar surface. The Constellation elements (Orion, Altair, Earth Departure Stage, and Ares launch vehicles) will require a lunar navigation architecture for navigation state updates during lunar-class missions. Orion in particular has baselined earth-based ground direct tracking as the primary source for much of its absolute navigation needs. However, due to the uncertainty in the lunar navigation architecture, the Orion program has had to make certain assumptions on the capabilities of such architectures in order to adequately scale the vehicle design trade space. The following paper outlines lunar navigation requirements, the Orion program assumptions, and the impacts of these assumptions to the lunar navigation architecture design. The selection of potential sites was based upon geometric baselines, logistical feasibility, redundancy, and abort support capability. Simulated navigation covariances mapped to entry interface flightpath- angle uncertainties were used to evaluate knowledge errors. A minimum ground station architecture was identified consisting of Goldstone, Madrid, Canberra, Santiago, Hartebeeshoek, Dongora, Hawaii, Guam, and Ascension Island (or the geometric equivalent).

  11. E-navigation Services for Non-SOLAS Ships

    Directory of Open Access Journals (Sweden)

    Kwang An

    2016-06-01

    Full Text Available It is clearly understood that the main benefits of e-navigation are improved safety and better protection of the environment through the promotion of standards of navigational system and a reduction in human error. In order to meet the expectations on the benefit of e-navigation, e-navigation services should be more focused on non-SOLAS ships. The purpose of this paper is to present necessary e-navigation services for non-SOLAS ships in order to prevent marine accidents in Korean coastal waters. To meet the objectives of the study, an examination on the present navigation and communication system for non-SOLAS ships was performed. Based on the IMO's e-navigation Strategy Implementation Plan (SIP and Korea's national SIP for e-navigation, future trends for the development and implementation of e-navigation were discussed. Consequently, Electronic Navigational Chart (ENC download and ENC up-date service, ENC streaming service, route support service and communication support service based on Maritime Cloud were presented as essential e-navigation services for non-SOLAS ships. This study will help for the planning and designing of the Korean e-navigation system. It is expected that the further researches on the navigation support systems based on e-navigation will be carried out in order to implement the essential e-navigation services for non-SOLAS ships.

  12. Ecological Restoration: Guidance from Theory

    Directory of Open Access Journals (Sweden)

    Joy Zedler

    2005-09-01

    Full Text Available A review of the science and practice of ecosystem restoration led me to identify key ecological theories and concepts that are relevant to planning, implementing, and sustaining restoration efforts. From experience with actual restoration projects, I provide guidance for improving the restoration process. Despite an abundance of theory and guidance, restoration goals are not always achieved, and pathways toward targets are not highly predictable. This is understandable, since each restoration project has many constraints and unique challenges. To improve restoration progress, I advise that sites be designed as experiments to allow learning while doing. At least the larger projects can be restored in phases, each designed as experimental treatments to test alternative restoration approaches. Subsequent phases can then adopt one or more of the treatments that best achieved goals in earlier phases while applying new tests of other restoration measures. Both science and restoration can progress simultaneously. This phased, experimental approach (called “adaptive restoration” is an effective tool for improving restoration when monitoring, assessment, interpretation and research are integrated into the process.

  13. Helicopter Field Testing of NASA's Autonomous Landing and Hazard Avoidance Technology (ALHAT) System fully Integrated with the Morpheus Vertical Test Bed Avionics

    Science.gov (United States)

    Epp, Chirold D.; Robertson, Edward A.; Ruthishauser, David K.

    2013-01-01

    The Autonomous Landing and Hazard Avoidance Technology (ALHAT) Project was chartered to develop and mature to a Technology Readiness Level (TRL) of six an autonomous system combining guidance, navigation and control with real-time terrain sensing and recognition functions for crewed, cargo, and robotic planetary landing vehicles. The ALHAT System must be capable of identifying and avoiding surface hazards to enable a safe and accurate landing to within tens of meters of designated and certified landing sites anywhere on a planetary surface under any lighting conditions. This is accomplished with the core sensing functions of the ALHAT system: Terrain Relative Navigation (TRN), Hazard Detection and Avoidance (HDA), and Hazard Relative Navigation (HRN). The NASA plan for the ALHAT technology is to perform the TRL6 closed loop demonstration on the Morpheus Vertical Test Bed (VTB). The first Morpheus vehicle was lost in August of 2012 during free-flight testing at Kennedy Space Center (KSC), so the decision was made to perform a helicopter test of the integrated ALHAT System with the Morpheus avionics over the ALHAT planetary hazard field at KSC. The KSC helicopter tests included flight profiles approximating planetary approaches, with the entire ALHAT system interfaced with all appropriate Morpheus subsystems and operated in real-time. During these helicopter flights, the ALHAT system imaged the simulated lunar terrain constructed in FY2012 to support ALHAT/Morpheus testing at KSC. To the best of our knowledge, this represents the highest fidelity testing of a system of this kind to date. During this helicopter testing, two new Morpheus landers were under construction at the Johnson Space Center to support the objective of an integrated ALHAT/Morpheus free-flight demonstration. This paper provides an overview of this helicopter flight test activity, including results and lessons learned, and also provides an overview of recent integrated testing of ALHAT on the second

  14. A Vision/Inertia Integrated Positioning Method Using Position and Orientation Matching

    Directory of Open Access Journals (Sweden)

    Xiaoyue Zhang

    2017-01-01

    Full Text Available A vision/inertia integrated positioning method using position and orientation matching which can be adopted on intelligent vehicle such as automated guided vehicle (AGV and mobile robot is proposed in this work. The method is introduced firstly. Landmarks are placed into the navigation field and camera and inertial measurement unit (IMU are installed on the vehicle. Vision processor calculates the azimuth and position information from the pictures which include artificial landmarks with the known direction and position. Inertial navigation system (INS calculates the azimuth and position of vehicle in real time and the calculated pixel position of landmark can be computed from the INS output position. Then the needed mathematical models are established and integrated navigation is implemented by Kalman filter with the observation of azimuth and the calculated pixel position of landmark. Navigation errors and IMU errors are estimated and compensated in real time so that high precision navigation results can be got. Finally, simulation and test are performed, respectively. Both simulation and test results prove that this vision/inertia integrated positioning method using position and orientation matching has feasibility and it can achieve centimeter-level autonomic continuous navigation.

  15. Indoor navigation by image recognition

    Science.gov (United States)

    Choi, Io Teng; Leong, Chi Chong; Hong, Ka Wo; Pun, Chi-Man

    2017-07-01

    With the progress of smartphones hardware, it is simple on smartphone using image recognition technique such as face detection. In addition, indoor navigation system development is much slower than outdoor navigation system. Hence, this research proves a usage of image recognition technique for navigation in indoor environment. In this paper, we introduced an indoor navigation application that uses the indoor environment features to locate user's location and a route calculating algorithm to generate an appropriate path for user. The application is implemented on Android smartphone rather than iPhone. Yet, the application design can also be applied on iOS because the design is implemented without using special features only for Android. We found that digital navigation system provides better and clearer location information than paper map. Also, the indoor environment is ideal for Image recognition processing. Hence, the results motivate us to design an indoor navigation system using image recognition.

  16. Introduction to the Navigation Team: Johnson Space Center EG6 Internship

    Science.gov (United States)

    Gualdoni, Matthew

    2017-01-01

    The EG6 navigation team at NASA Johnson Space Center, like any team of engineers, interacts with the engineering process from beginning to end; from exploring solutions to a problem, to prototyping and studying the implementations, all the way to polishing and verifying a final flight-ready design. This summer, I was privileged enough to gain exposure to each of these processes, while also getting to truly experience working within a team of engineers. My summer can be broken up into three projects: i) Initial study and prototyping: investigating a manual navigation method that can be utilized onboard Orion in the event of catastrophic failure of navigation systems; ii) Finalizing and verifying code: altering a software routine to improve its robustness and reliability, as well as designing unit tests to verify its performance; and iii) Development of testing equipment: assisting in developing and integrating of a high-fidelity testbed to verify the performance of software and hardware.

  17. Navigation Lights - USACE IENC

    Data.gov (United States)

    Department of Homeland Security — These inland electronic Navigational charts (IENCs) were developed from available data used in maintenance of Navigation channels. Users of these IENCs should be...

  18. Surface navigation on Mars with a Navigation Satellite

    Science.gov (United States)

    Vijayaraghavan, A.; Thurman, Sam W.; Kahn, Robert D.; Hastrup, Rolf C.

    Radiometric navigation data from the Deep Space Network (DSN) stations on the earth to transponders and other surface elements such as rovers and landers on Mars, can determine their positions to only within a kilometer in inertial space. The positional error is mostly in the z-component of the surface element parallel to the Martian spin-axis. However, with Doppler and differenced-Doppler data from a Navigation Satellite in orbit around Mars to two or more of such transponders on the planetary surface, their positions can be determined to within 15 meters (or 20 meters for one-way Doppler beacons on Mars) in inertial space. In this case, the transponders (or other vehicles) on Mars need not even be capable of directly communicating to the earth. When the Navigation Satellite data is complemented by radiometric observations from the DSN stations also, directly to the surface elements on Mars, their positions can be determined to within 3 meters in inertial space. The relative positions of such surface elements on Mars (relative to one another) in Mars-fixed coordinates, however, can be determined to within 5 meters from simply range and Doppler data from the DSN stations to the surface elements. These results are obtained from covariance studies assuming X-band data noise levels and data-arcs not exceeding 10 days. They are significant in the planning and deployment of a Mars-based navigation network necessary to support real-time operations during critical phases of manned exploration of Mars.

  19. Intelligent Behavioral Action Aiding for Improved Autonomous Image Navigation

    Science.gov (United States)

    2012-09-13

    odometry, SICK laser scanning unit ( Lidar ), Inertial Measurement Unit (IMU) and ultrasonic distance measurement system (Figure 32). The Lidar , IMU...2010, July) GPS world. [Online]. http://www.gpsworld.com/tech-talk- blog/gnss-independent-navigation-solution-using-integrated- lidar -data-11378 [4...Milford, David McKinnon, Michael Warren, Gordon Wyeth, and Ben Upcroft, "Feature-based Visual Odometry and Featureless Place Recognition for SLAM in

  20. Nonlinear unbiased minimum-variance filter for Mars entry autonomous navigation under large uncertainties and unknown measurement bias.

    Science.gov (United States)

    Xiao, Mengli; Zhang, Yongbo; Fu, Huimin; Wang, Zhihua

    2018-05-01

    High-precision navigation algorithm is essential for the future Mars pinpoint landing mission. The unknown inputs caused by large uncertainties of atmospheric density and aerodynamic coefficients as well as unknown measurement biases may cause large estimation errors of conventional Kalman filters. This paper proposes a derivative-free version of nonlinear unbiased minimum variance filter for Mars entry navigation. This filter has been designed to solve this problem by estimating the state and unknown measurement biases simultaneously with derivative-free character, leading to a high-precision algorithm for the Mars entry navigation. IMU/radio beacons integrated navigation is introduced in the simulation, and the result shows that with or without radio blackout, our proposed filter could achieve an accurate state estimation, much better than the conventional unscented Kalman filter, showing the ability of high-precision Mars entry navigation algorithm. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.

  1. An Online Solution of LiDAR Scan Matching Aided Inertial Navigation System for Indoor Mobile Mapping

    Directory of Open Access Journals (Sweden)

    Xiaoji Niu

    2017-01-01

    Full Text Available Multisensors (LiDAR/IMU/CAMERA integrated Simultaneous Location and Mapping (SLAM technology for navigation and mobile mapping in a GNSS-denied environment, such as indoor areas, dense forests, or urban canyons, becomes a promising solution. An online (real-time version of such system can extremely extend its applications, especially for indoor mobile mapping. However, the real-time response issue of multisensors is a big challenge for an online SLAM system, due to the different sampling frequencies and processing time of different algorithms. In this paper, an online Extended Kalman Filter (EKF integrated algorithm of LiDAR scan matching and IMU mechanization for Unmanned Ground Vehicle (UGV indoor navigation system is introduced. Since LiDAR scan matching is considerably more time consuming than the IMU mechanism, the real-time synchronous issue is solved via a one-step-error-state-transition method in EKF. Stationary and dynamic field tests had been performed using a UGV platform along typical corridor of office building. Compared to the traditional sequential postprocessed EKF algorithm, the proposed method can significantly mitigate the time delay of navigation outputs under the premise of guaranteeing the positioning accuracy, which can be used as an online navigation solution for indoor mobile mapping.

  2. Semiotic resources for navigation

    DEFF Research Database (Denmark)

    Due, Brian Lystgaard; Lange, Simon Bierring

    2018-01-01

    This paper describes two typical semiotic resources blind people use when navigating in urban areas. Everyone makes use of a variety of interpretive semiotic resources and senses when navigating. For sighted individuals, this especially involves sight. Blind people, however, must rely on everything...... else than sight, thereby substituting sight with other modalities and distributing the navigational work to other semiotic resources. Based on a large corpus of fieldwork among blind people in Denmark, undertaking observations, interviews, and video recordings of their naturally occurring practices...... of walking and navigating, this paper shows how two prototypical types of semiotic resources function as helpful cognitive extensions: the guide dog and the white cane. This paper takes its theoretical and methodological perspective from EMCA multimodal interaction analysis....

  3. Mars Science Laboratory Entry Guidance Improvements for Mars 2018 (DRAFT)

    Science.gov (United States)

    Garcia-Llama, Eduardo; Winski, Richard G.; Shidner, Jeremy D.; Ivanov, Mark C.; Grover, Myron R.; Prakash, Ravi

    2011-01-01

    In 2011, the Mars Science Laboratory (MSL) will be launched in a mission to deliver the largest and most capable rover to date to the surface of Mars. A follow on MSL-derived mission, referred to as Mars 2018, is planned for 2018. Mars 2018 goals include performance enhancements of the Entry, Descent and Landing over that of its predecessor MSL mission of 2011. This paper will discuss the main elements of the modified 2018 EDL preliminary design that will increase performance on the entry phase of the mission. In particular, these elements will increase the parachute deploy altitude to allow for more time margin during the subsequent descent and landing phases and reduce the delivery ellipse size at parachute deploy through modifications in the entry reference trajectory design, guidance trigger logic design, and the effect of additional navigation hardware.

  4. Microwave ablation assisted by a real-time virtual navigation system for hepatocellular carcinoma undetectable by conventional ultrasonography

    International Nuclear Information System (INIS)

    Liu Fangyi; Yu Xiaoling; Liang Ping; Cheng Zhigang; Han Zhiyu; Dong Baowei; Zhang Xiaohong

    2012-01-01

    Objectives: To evaluate the efficiency and feasibility of microwave (MW) ablation assisted by a real-time virtual navigation system for hepatocellular carcinoma (HCC) undetectable by conventional ultrasonography. Methods: 18 patients with 18 HCC nodules (undetectable on conventional US but detectable by intravenous contrast-enhanced CT or MRI) were enrolled in this study. Before MW ablation, US images and MRI or CT images were synchronized using the internal markers at the best timing of the inspiration. Thereafter, MW ablation was performed under real-time virtual navigation system guidance. Therapeutic efficacy was assessed by the result of contrast-enhanced imagings after the treatment. Results: The target HCC nodules could be detected with fusion images in all patients. The time required for image fusion was 8–30 min (mean, 13.3 ± 5.7 min). 17 nodules were successfully ablated according to the contrast enhanced imagings 1 month after ablation. The technique effectiveness rate was 94.44% (17/18). The follow-up time was 3–12 months (median, 6 months) in our study. No severe complications occurred. No local recurrence was observed in any patients. Conclusions: MW ablation assisted by a real-time virtual navigation system is a feasible and efficient treatment of patients with HCC undetectable by conventional ultrasonography.

  5. Navigation in endoscopic sinus surgery: the first Indian experience.

    Science.gov (United States)

    Rai, Devinder; Munjal, Manish; Rai, Varun

    2013-08-01

    Although the use of image guidance surgery (IGS) is standard practice in developed countries, it has not been in use in Indian Otolaryngology ever since its clinical inception in 1994. Some clinically interesting applications, relevant indications, practical tips and results in the Indian context are presented. Usage technique and data presentation. Indications based on AAO-HNS 2002 guidelines seem valid, and though the accuracy parameters remain still guarded, in line with the best technology available, based on the evidences of scattered reports and expert opinions, the use of navigation can be recommended as state of the art. IGS provides reliable information to a sinus surgeon in difficult circumstances. Its adaptation fortunately does not require a significant learning curve as it does not change the methodology of the surgical procedure. It can be an excellent teaching tool, but its use does not replace proper surgical training.

  6. 6TH Saint Petersburg International Conference on Integrated Navigation Systems. (6eme Conference Internationale de Saint Petersbourg sur les Systemes de Navigation Integree)

    Science.gov (United States)

    1999-10-01

    Kharisov V.N., Perov A.I., Boldin V.A. (editors). 1977. The global satelllite radio-navigational system 20. Wu W.-R. Target tracking with glint...the coordinates of the OP techniques for their searching and extracting in deep seas. These techniques. have yielded Researches have shown that, an OP

  7. CT-MR image data fusion for computer assisted navigated neurosurgery of temporal bone tumors

    International Nuclear Information System (INIS)

    Nemec, Stefan Franz; Donat, Markus Alexander; Mehrain, Sheida; Friedrich, Klaus; Krestan, Christian; Matula, Christian; Imhof, Herwig; Czerny, Christian

    2007-01-01

    Purpose: To demonstrate the value of multi detector computed tomography (MDCT) and magnetic resonance imaging (MRI) in the preoperative work up of temporal bone tumors and to present, especially, CT and MR image fusion for surgical planning and performance in computer assisted navigated neurosurgery of temporal bone tumors. Materials and methods: Fifteen patients with temporal bone tumors underwent MDCT and MRI. MDCT was performed in high-resolution bone window level setting in axial plane. The reconstructed MDCT slice thickness was 0.8 mm. MRI was performed in axial and coronal plane with T2-weighted fast spin-echo (FSE) sequences, un-enhanced and contrast-enhanced T1-weighted spin-echo (SE) sequences, and coronal T1-weighted SE sequences with fat suppression and with 3D T1-weighted gradient-echo (GE) contrast-enhanced sequences in axial plane. The 3D T1-weighted GE sequence had a slice thickness of 1 mm. Image data sets of CT and 3D T1-weighted GE sequences were merged utilizing a workstation to create CT-MR fusion images. MDCT and MR images were separately used to depict and characterize lesions. The fusion images were utilized for interventional planning and intraoperative image guidance. The intraoperative accuracy of the navigation unit was measured, defined as the deviation between the same landmark in the navigation image and the patient. Results: Tumorous lesions of bone and soft tissue were well delineated and characterized by CT and MR images. The images played a crucial role in the differentiation of benign and malignant pathologies, which consisted of 13 benign and 2 malignant tumors. The CT-MR fusion images supported the surgeon in preoperative planning and improved surgical performance. The mean intraoperative accuracy of the navigation system was 1.25 mm. Conclusion: CT and MRI are essential in the preoperative work up of temporal bone tumors. CT-MR image data fusion presents an accurate tool for planning the correct surgical procedure and is a

  8. 33 CFR 401.54 - Interference with navigation aids.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Interference with navigation aids. 401.54 Section 401.54 Navigation and Navigable Waters SAINT LAWRENCE SEAWAY DEVELOPMENT CORPORATION... with navigation aids. (a) Aids to navigation shall not be interfered with or used as moorings. (b) No...

  9. Comparison of robust H∞ filter and Kalman filter for initial alignment of inertial navigation system

    Institute of Scientific and Technical Information of China (English)

    HAO Yan-ling; CHEN Ming-hui; LI Liang-jun; XU Bo

    2008-01-01

    There are many filtering methods that can be used for the initial alignment of an integrated inertial navigation system.This paper discussed the use of GPS,but focused on two kinds of filters for the initial alignment of an integrated strapdown inertial navigation system (SINS).One method is based on the Kalman filter (KF),and the other is based on the robust filter.Simulation results showed that the filter provides a quick transient response and a little more accurate estimate than KF,given substantial process noise or unknown noise statistics.So the robust filter is an effective and useful method for initial alignment of SINS.This research should make the use of SINS more popular,and is also a step for further research.

  10. LiDAR Scan Matching Aided Inertial Navigation System in GNSS-Denied Environments

    Directory of Open Access Journals (Sweden)

    Jian Tang

    2015-07-01

    Full Text Available A new scan that matches an aided Inertial Navigation System (INS with a low-cost LiDAR is proposed as an alternative to GNSS-based navigation systems in GNSS-degraded or -denied environments such as indoor areas, dense forests, or urban canyons. In these areas, INS-based Dead Reckoning (DR and Simultaneous Localization and Mapping (SLAM technologies are normally used to estimate positions as separate tools. However, there are critical implementation problems with each standalone system. The drift errors of velocity, position, and heading angles in an INS will accumulate over time, and on-line calibration is a must for sustaining positioning accuracy. SLAM performance is poor in featureless environments where the matching errors can significantly increase. Each standalone positioning method cannot offer a sustainable navigation solution with acceptable accuracy. This paper integrates two complementary technologies—INS and LiDAR SLAM—into one navigation frame with a loosely coupled Extended Kalman Filter (EKF to use the advantages and overcome the drawbacks of each system to establish a stable long-term navigation process. Static and dynamic field tests were carried out with a self-developed Unmanned Ground Vehicle (UGV platform—NAVIS. The results prove that the proposed approach can provide positioning accuracy at the centimetre level for long-term operations, even in a featureless indoor environment.

  11. Vision-aided inertial navigation system for robotic mobile mapping

    Science.gov (United States)

    Bayoud, Fadi; Skaloud, Jan

    2008-04-01

    A mapping system by vision-aided inertial navigation was developed for areas where GNSS signals are unreachable. In this framework, a methodology on the integration of vision and inertial sensors is presented, analysed and tested. The system employs the method of “SLAM: Simultaneous Localisation And Mapping” where the only external input available to the system at the beginning of the mapping mission is a number of features with known coordinates. SLAM is a term used in the robotics community to describe the problem of mapping the environment and at the same time using this map to determine the location of the mapping device. Differing from the robotics approach, the presented development stems from the frameworks of photogrammetry and kinematic geodesy that are merged in two filters that run in parallel: the Least-Squares Adjustment (LSA) for features coordinates determination and the Kalman filter (KF) for navigation correction. To test this approach, a mapping system-prototype comprising two CCD cameras and one Inertial Measurement Unit (IMU) is introduced. Conceptually, the outputs of the LSA photogrammetric resection are used as the external measurements for the KF that corrects the inertial navigation. The filtered position and orientation are subsequently employed in the photogrammetric intersection to map the surrounding features that are used as control points for the resection in the next epoch. We confirm empirically the dependency of navigation performance on the quality of the images and the number of tracked features, as well as on the geometry of the stereo-pair. Due to its autonomous nature, the SLAM's performance is further affected by the quality of IMU initialisation and the a-priory assumptions on error distribution. Using the example of the presented system we show that centimetre accuracy can be achieved in both navigation and mapping when the image geometry is optimal.

  12. Sensor fusion for mobile robot navigation

    International Nuclear Information System (INIS)

    Kam, M.; Zhu, X.; Kalata, P.

    1997-01-01

    The authors review techniques for sensor fusion in robot navigation, emphasizing algorithms for self-location. These find use when the sensor suite of a mobile robot comprises several different sensors, some complementary and some redundant. Integrating the sensor readings, the robot seeks to accomplish tasks such as constructing a map of its environment, locating itself in that map, and recognizing objects that should be avoided or sought. The review describes integration techniques in two categories: low-level fusion is used for direct integration of sensory data, resulting in parameter and state estimates; high-level fusion is used for indirect integration of sensory data in hierarchical architectures, through command arbitration and integration of control signals suggested by different modules. The review provides an arsenal of tools for addressing this (rather ill-posed) problem in machine intelligence, including Kalman filtering, rule-based techniques, behavior based algorithms and approaches that borrow from information theory, Dempster-Shafer reasoning, fuzzy logic and neural networks. It points to several further-research needs, including: robustness of decision rules; simultaneous consideration of self-location, motion planning, motion control and vehicle dynamics; the effect of sensor placement and attention focusing on sensor fusion; and adaptation of techniques from biological sensor fusion

  13. Inertial Navigation System/Doppler Velocity Log (INS/DVL Fusion with Partial DVL Measurements

    Directory of Open Access Journals (Sweden)

    Asaf Tal

    2017-02-01

    Full Text Available The Technion autonomous underwater vehicle (TAUV is an ongoing project aiming to develop and produce a small AUV to carry on research missions, including payload dropping, and to demonstrate acoustic communication. Its navigation system is based on an inertial navigation system (INS aided by a Doppler velocity log (DVL, magnetometer, and pressure sensor (PS. In many INSs, such as the one used in TAUV, only the velocity vector (provided by the DVL can be used for aiding the INS, i.e., enabling only a loosely coupled integration approach. In cases of partial DVL measurements, such as failure to maintain bottom lock, the DVL cannot estimate the vehicle velocity. Thus, in partial DVL situations no velocity data can be integrated into the TAUV INS, and as a result its navigation solution will drift in time. To circumvent that problem, we propose a DVL-based vehicle velocity solution using the measured partial raw data of the DVL and additional information, thereby deriving an extended loosely coupled (ELC approach. The implementation of the ELC approach requires only software modification. In addition, we present the TAUV six degrees of freedom (6DOF simulation that includes all functional subsystems. Using this simulation, the proposed approach is evaluated and the benefit of using it is shown.

  14. Emergency Navigation without an Infrastructure

    Directory of Open Access Journals (Sweden)

    Erol Gelenbe

    2014-08-01

    Full Text Available Emergency navigation systems for buildings and other built environments, such as sport arenas or shopping centres, typically rely on simple sensor networks to detect emergencies and, then, provide automatic signs to direct the evacuees. The major drawbacks of such static wireless sensor network (WSN-based emergency navigation systems are the very limited computing capacity, which makes adaptivity very difficult, and the restricted battery power, due to the low cost of sensor nodes for unattended operation. If static wireless sensor networks and cloud-computing can be integrated, then intensive computations that are needed to determine optimal evacuation routes in the presence of time-varying hazards can be offloaded to the cloud, but the disadvantages of limited battery life-time at the client side, as well as the high likelihood of system malfunction during an emergency still remain. By making use of the powerful sensing ability of smart phones, which are increasingly ubiquitous, this paper presents a cloud-enabled indoor emergency navigation framework to direct evacuees in a coordinated fashion and to improve the reliability and resilience for both communication and localization. By combining social potential fields (SPF and a cognitive packet network (CPN-based algorithm, evacuees are guided to exits in dynamic loose clusters. Rather than relying on a conventional telecommunications infrastructure, we suggest an ad hoc cognitive packet network (AHCPN-based protocol to adaptively search optimal communication routes between portable devices and the network egress nodes that provide access to cloud servers, in a manner that spares the remaining battery power of smart phones and minimizes the time latency. Experimental results through detailed simulations indicate that smart human motion and smart network management can increase the survival rate of evacuees and reduce the number of drained smart phones in an evacuation process.

  15. Emergency navigation without an infrastructure.

    Science.gov (United States)

    Gelenbe, Erol; Bi, Huibo

    2014-08-18

    Emergency navigation systems for buildings and other built environments, such as sport arenas or shopping centres, typically rely on simple sensor networks to detect emergencies and, then, provide automatic signs to direct the evacuees. The major drawbacks of such static wireless sensor network (WSN)-based emergency navigation systems are the very limited computing capacity, which makes adaptivity very difficult, and the restricted battery power, due to the low cost of sensor nodes for unattended operation. If static wireless sensor networks and cloud-computing can be integrated, then intensive computations that are needed to determine optimal evacuation routes in the presence of time-varying hazards can be offloaded to the cloud, but the disadvantages of limited battery life-time at the client side, as well as the high likelihood of system malfunction during an emergency still remain. By making use of the powerful sensing ability of smart phones, which are increasingly ubiquitous, this paper presents a cloud-enabled indoor emergency navigation framework to direct evacuees in a coordinated fashion and to improve the reliability and resilience for both communication and localization. By combining social potential fields (SPF) and a cognitive packet network (CPN)-based algorithm, evacuees are guided to exits in dynamic loose clusters. Rather than relying on a conventional telecommunications infrastructure, we suggest an ad hoc cognitive packet network (AHCPN)-based protocol to adaptively search optimal communication routes between portable devices and the network egress nodes that provide access to cloud servers, in a manner that spares the remaining battery power of smart phones and minimizes the time latency. Experimental results through detailed simulations indicate that smart human motion and smart network management can increase the survival rate of evacuees and reduce the number of drained smart phones in an evacuation process.

  16. Designing Automated Guidance to Promote Productive Revision of Science Explanations

    Science.gov (United States)

    Tansomboon, Charissa; Gerard, Libby F.; Vitale, Jonathan M.; Linn, Marcia C.

    2017-01-01

    Supporting students to revise their written explanations in science can help students to integrate disparate ideas and develop a coherent, generative account of complex scientific topics. Using natural language processing to analyze student written work, we compare forms of automated guidance designed to motivate productive revision and help…

  17. Equipment design guidance document for flammable gas waste storage tank new equipment

    International Nuclear Information System (INIS)

    Smet, D.B.

    1996-01-01

    This document is intended to be used as guidance for design engineers who are involved in design of new equipment slated for use in Flammable Gas Waste Storage Tanks. The purpose of this document is to provide design guidance for all new equipment intended for application into those Hanford storage tanks in which flammable gas controls are required to be addressed as part of the equipment design. These design criteria are to be used as guidance. The design of each specific piece of new equipment shall be required, as a minimum to be reviewed by qualified Unreviewed Safety Question evaluators as an integral part of the final design approval. Further Safety Assessment may be also needed. This guidance is intended to be used in conjunction with the Operating Specifications Documents (OSDs) established for defining work controls in the waste storage tanks. The criteria set forth should be reviewed for applicability if the equipment will be required to operate in locations containing unacceptable concentrations of flammable gas

  18. Graphic Turbulence Guidance

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Forecast turbulence hazards identified by the Graphical Turbulence Guidance algorithm. The Graphical Turbulence Guidance product depicts mid-level and upper-level...

  19. Real-time precision pedestrian navigation solution using Inertial Navigation System and Global Positioning System

    OpenAIRE

    Yong-Jin Yoon; King Ho Holden Li; Jiahe Steven Lee; Woo-Tae Park

    2015-01-01

    Global Positioning System and Inertial Navigation System can be used to determine position and velocity. A Global Positioning System module is able to accurately determine position without sensor drift, but its usage is limited in heavily urbanized environments and heavy vegetation. While high-cost tactical-grade Inertial Navigation System can determine position accurately, low-cost micro-electro-mechanical system Inertial Navigation System sensors are plagued by significant errors. Global Po...

  20. Switching from reaching to navigation: differential cognitive strategies for spatial memory in children and adults.

    Science.gov (United States)

    Belmonti, Vittorio; Cioni, Giovanni; Berthoz, Alain

    2015-07-01

    Navigational and reaching spaces are known to involve different cognitive strategies and brain networks, whose development in humans is still debated. In fact, high-level spatial processing, including allocentric location encoding, is already available to very young children, but navigational strategies are not mature until late childhood. The Magic Carpet (MC) is a new electronic device translating the traditional Corsi Block-tapping Test (CBT) to navigational space. In this study, the MC and the CBT were used to assess spatial memory for navigation and for reaching, respectively. Our hypothesis was that school-age children would not treat MC stimuli as navigational paths, assimilating them to reaching sequences. Ninety-one healthy children aged 6 to 11 years and 18 adults were enrolled. Overall short-term memory performance (span) on both tests, effects of sequence geometry, and error patterns according to a new classification were studied. Span increased with age on both tests, but relatively more in navigational than in reaching space, particularly in males. Sequence geometry specifically influenced navigation, not reaching. The number of body rotations along the path affected MC performance in children more than in adults, and in women more than in men. Error patterns indicated that navigational sequences were increasingly retained as global paths across development, in contrast to separately stored reaching locations. A sequence of spatial locations can be coded as a navigational path only if a cognitive switch from a reaching mode to a navigation mode occurs. This implies the integration of egocentric and allocentric reference frames, of visual and idiothetic cues, and access to long-term memory. This switch is not yet fulfilled at school age due to immature executive functions. © 2014 John Wiley & Sons Ltd.

  1. Powered Explicit Guidance Modifications and Enhancements for Space Launch System Block-1 and Block-1B Vehicles

    Science.gov (United States)

    Von der Porten, Paul; Ahmad, Naeem; Hawkins, Matt; Fill, Thomas

    2018-01-01

    NASA is currently building the Space Launch System (SLS) Block-1 launch vehicle for the Exploration Mission 1 (EM-1) test flight. NASA is also currently designing the next evolution of SLS, the Block-1B. The Block-1 and Block-1B vehicles will use the Powered Explicit Guidance (PEG) algorithm (of Space Shuttle heritage) for closed loop guidance. To accommodate vehicle capabilities and design for future evolutions of SLS, modifications were made to PEG for Block-1 to handle multi-phase burns, provide PEG updated propulsion information, and react to a core stage engine out. In addition, due to the relatively low thrust-to-weight ratio of the Exploration Upper Stage (EUS) and EUS carrying out Lunar Vicinity and Earth Escape missions, certain enhancements to the Block-1 PEG algorithm are needed to perform Block-1B missions to account for long burn arcs and target translunar and hyperbolic orbits. This paper describes the design and implementation of modifications to the Block-1 PEG algorithm as compared to Space Shuttle. Furthermore, this paper illustrates challenges posed by the Block-1B vehicle and the required PEG enhancements. These improvements make PEG capable for use on the SLS Block-1B vehicle as part of the Guidance, Navigation, and Control (GN&C) System.

  2. Navigating oceans and cultures: Polynesian and European navigation systems in the late eighteenth century

    Science.gov (United States)

    Walker, M.

    2012-05-01

    Significant differences in the rotation of the celestial dome between the tropical and temperate zones did not stop the peoples of either the tropical Pacific or temperate Europe from using geocentric astronomy to guide exploration of the oceans. Although the differences in the night sky contributed to differences between the Pacific Island and European systems for navigation at sea, the two navigation systems exhibit substantial similarities. Both systems define positions on the surface of the Earth using two coordinates that vary at right angles to each other and use stars, and to a lesser extent the sun, to determine directions. This essay explores similarities and differences in the use of geocentric astronomy for navigation at sea by the peoples of Polynesia and Europe in the late eighteenth century. Captain Cook's orders to discover the unknown southern continent after observing the transit of Venus combined with differences in language and culture to obscure the deeper similarities between the navigation systems used by Cook and the Polynesians. Although it was a further 200 years before anthropologists studied Pacific navigation, collaborations in voyaging with communities in Oceania demonstrated the effectiveness of Pacific navigation systems, revived interest in traditional voyaging in island communities around the Pacific, and potentially open the way for further collaborations in other areas.

  3. Geometric Fuzzy Techniques for Guidance of Visually Impaired People

    Directory of Open Access Journals (Sweden)

    Adán Landa-Hernández

    2013-01-01

    Full Text Available In this paper we present the design of a device to guide the visually impaired person who normally uses a cane. We propose a non-invasive device that will help blind and visually impaired people to navigate. The system uses stereoscopic vision, a RGB-D sensor and an IMU to process images and to compute the distances from obstacles relative to cameras and to search for free walking paths in the scene. This computing is done using stereo vision, vanishing points, and fuzzy rules. Vanishing points are used to obtain a main orientation in structured spaces. Since the guidance system is related to a spatial reference system, the vanishing point is used like a virtual compass that helps the blind to orient him- or herself towards a goal. Reinforced with fuzzy decision rules, the system supports the blind in avoiding obstacles, thus the blind person is able to cross structured spaces and avoid obstacles without the need for a cane.

  4. Multi-Flight-Phase GPS Navigation Filter Applications to Terrestrial Vehicle Navigation and Positioning

    Science.gov (United States)

    Park, Young W.; Montez, Moises N.

    1994-01-01

    A candidate onboard space navigation filter demonstrated excellent performance (less than 8 meter level RMS semi-major axis accuracy) in performing orbit determination of a low-Earth orbit Explorer satellite using single-frequency real GPS data. This performance is significantly better than predicted by other simulation studies using dual-frequency GPS data. The study results revealed the significance of two new modeling approaches evaluated in the work. One approach introduces a single-frequency ionospheric correction through pseudo-range and phase range averaging implementation. The other approach demonstrates a precise axis-dependent characterization of dynamic sample space uncertainty to compute a more accurate Kalman filter gain. Additionally, this navigation filter demonstrates a flexibility to accommodate both perturbational dynamic and observational biases required for multi-flight phase and inhomogeneous application environments. This paper reviews the potential application of these methods and the filter structure to terrestrial vehicle and positioning applications. Both the single-frequency ionospheric correction method and the axis-dependent state noise modeling approach offer valuable contributions in cost and accuracy improvements for terrestrial GPS receivers. With a modular design approach to either 'plug-in' or 'unplug' various force models, this multi-flight phase navigation filter design structure also provides a versatile GPS navigation software engine for both atmospheric and exo-atmospheric navigation or positioning use, thereby streamlining the flight phase or application-dependent software requirements. Thus, a standardized GPS navigation software engine that can reduce the development and maintenance cost of commercial GPS receivers is now possible.

  5. Global navigation satellite systems performance analysis and augmentation strategies in aviation

    Science.gov (United States)

    Sabatini, Roberto; Moore, Terry; Ramasamy, Subramanian

    2017-11-01

    Based Augmentation System (GBAS), Aircraft Based Augmentation System (ABAS) and Receiver Autonomous Integrity Monitoring (RAIM). Furthermore, by employing multi-GNSS constellations and multi-sensor data fusion techniques, improvements in availability and continuity can be obtained. SBAS is designed to improve GNSS system integrity and accuracy for aircraft navigation and landing, while an alternative approach to GNSS augmentation is to transmit integrity and differential correction messages from ground-based augmentation systems (GBAS). In addition to existing space and ground based augmentation systems, GNSS augmentation may take the form of additional information being provided by other on-board avionics systems, such as in ABAS. As these on-board systems normally operate via separate principles than GNSS, they are not subject to the same sources of error or interference. Using suitable data link and data processing technologies on the ground, a certified ABAS capability could be a core element of a future GNSS Space-Ground-Aircraft Augmentation Network (SGAAN). Although current augmentation systems can provide significant improvement of GNSS navigation performance, a properly designed and flight-certified SGAAN could play a key role in trusted autonomous system and cyber-physical system applications such as UAS Sense-and-Avoid (SAA).

  6. Ergonomics action research II: a framework for integrating HF into work system design.

    Science.gov (United States)

    Neumann, W P; Village, J

    2012-01-01

    This paper presents a conceptual framework that can support efforts to integrate human factors (HF) into the work system design process, where improved and cost-effective application of HF is possible. The framework advocates strategies of broad stakeholder participation, linking of performance and health goals, and process focussed change tools that can help practitioners engage in improvements to embed HF into a firm's work system design process. Recommended tools include business process mapping of the design process, implementing design criteria, using cognitive mapping to connect to managers' strategic goals, tactical use of training and adopting virtual HF (VHF) tools to support the integration effort. Consistent with organisational change research, the framework provides guidance but does not suggest a strict set of steps. This allows more adaptability for the practitioner who must navigate within a particular organisational context to secure support for embedding HF into the design process for improved operator wellbeing and system performance. There has been little scientific literature about how a practitioner might integrate HF into a company's work system design process. This paper proposes a framework for this effort by presenting a coherent conceptual framework, process tools, design tools and procedural advice that can be adapted for a target organisation.

  7. Usability Testing of Two Ambulatory EHR Navigators.

    Science.gov (United States)

    Hultman, Gretchen; Marquard, Jenna; Arsoniadis, Elliot; Mink, Pamela; Rizvi, Rubina; Ramer, Tim; Khairat, Saif; Fickau, Keri; Melton, Genevieve B

    2016-01-01

    Despite widespread electronic health record (EHR) adoption, poor EHR system usability continues to be a significant barrier to effective system use for end users. One key to addressing usability problems is to employ user testing and user-centered design. To understand if redesigning an EHR-based navigation tool with clinician input improved user performance and satisfaction. A usability evaluation was conducted to compare two versions of a redesigned ambulatory navigator. Participants completed tasks for five patient cases using the navigators, while employing a think-aloud protocol. The tasks were based on Meaningful Use (MU) requirements. The version of navigator did not affect perceived workload, and time to complete tasks was longer in the redesigned navigator. A relatively small portion of navigator content was used to complete the MU-related tasks, though navigation patterns were highly variable across participants for both navigators. Preferences for EHR navigation structures appeared to be individualized. This study demonstrates the importance of EHR usability assessments to evaluate group and individual performance of different interfaces and preferences for each design.

  8. A discussion of higher order software concepts as they apply to functional requirements and specifications. [space shuttles and guidance

    Science.gov (United States)

    Hamilton, M.

    1973-01-01

    The entry guidance software functional requirements (requirements design phase), its architectural requirements (specifications design phase), and the entry guidance software verified code are discussed. It was found that the proper integration of designs at both the requirements and specifications levels are of high priority consideration.

  9. 75 FR 50884 - Navigation and Navigable Waters; Technical, Organizational, and Conforming Amendments, Sector...

    Science.gov (United States)

    2010-08-18

    ... 3 and 165 to reflect changes in Coast Guard internal organizational structure. Sector Portland and... 1625-ZA25 Navigation and Navigable Waters; Technical, Organizational, and Conforming Amendments, Sector... Waters; Technical, Organizational, and Conforming Amendments, Sector Columbia River.'' 2. On page 48564...

  10. Integrating Top-down and Bottom-up Cybersecurity Guidance using XML

    Science.gov (United States)

    Lubell, Joshua

    2016-01-01

    This paper describes a markup-based approach for synthesizing disparate information sources and discusses a software implementation of the approach. The implementation makes it easier for people to use two complementary, but differently structured, guidance specifications together: the (top-down) Cybersecurity Framework and the (bottom-up) National Institute of Standards and Technology Special Publication 800-53 security control catalog. An example scenario demonstrates how the software implementation can help a security professional select the appropriate safeguards for restricting unauthorized access to an Industrial Control System. The implementation and example show the benefits of this approach and suggest its potential application to disciplines other than cybersecurity. PMID:27795810

  11. Integrating Top-down and Bottom-up Cybersecurity Guidance using XML.

    Science.gov (United States)

    Lubell, Joshua

    2016-08-01

    This paper describes a markup-based approach for synthesizing disparate information sources and discusses a software implementation of the approach. The implementation makes it easier for people to use two complementary, but differently structured, guidance specifications together: the (top-down) Cybersecurity Framework and the (bottom-up) National Institute of Standards and Technology Special Publication 800-53 security control catalog. An example scenario demonstrates how the software implementation can help a security professional select the appropriate safeguards for restricting unauthorized access to an Industrial Control System. The implementation and example show the benefits of this approach and suggest its potential application to disciplines other than cybersecurity.

  12. Intelligent Navigation for a Solar Powered Unmanned Underwater Vehicle

    Directory of Open Access Journals (Sweden)

    Francisco García-Córdova

    2013-04-01

    Full Text Available In this paper, an intelligent navigation system for an unmanned underwater vehicle powered by renewable energy and designed for shadow water inspection in missions of a long duration is proposed. The system is composed of an underwater vehicle, which tows a surface vehicle. The surface vehicle is a small boat with photovoltaic panels, a methanol fuel cell and communication equipment, which provides energy and communication to the underwater vehicle. The underwater vehicle has sensors to monitor the underwater environment such as sidescan sonar and a video camera in a flexible configuration and sensors to measure the physical and chemical parameters of water quality on predefined paths for long distances. The underwater vehicle implements a biologically inspired neural architecture for autonomous intelligent navigation. Navigation is carried out by integrating a kinematic adaptive neuro-controller for trajectory tracking and an obstacle avoidance adaptive neuro- controller. The autonomous underwater vehicle is capable of operating during long periods of observation and monitoring. This autonomous vehicle is a good tool for observing large areas of sea, since it operates for long periods of time due to the contribution of renewable energy. It correlates all sensor data for time and geodetic position. This vehicle has been used for monitoring the Mar Menor lagoon.

  13. Digital waterway construction based on inland electronic navigation chart

    Science.gov (United States)

    Wang, Xue; Pan, Junfeng; Zhu, Weiwei

    2015-12-01

    With advantages of large capacity, long distance, low energy consumption, low cost, less land occupation and light pollution, inland waterway transportation becomes one of the most important constituents of the comprehensive transportation system and comprehensive water resources utilization in China. As one of "three elements" of navigation, waterway is the important basis for the development of water transportation and plays a key supporting role in shipping economic. The paper discuss how to realize the informatization and digitization of waterway management based on constructing an integrated system of standard inland electronic navigation chart production, waterway maintenance, navigation mark remote sensing and control, ship dynamic management, and water level remote sensing and report, which can also be the foundation of the intelligent waterway construction. Digital waterway construction is an information project and also has a practical meaning for waterway. It can not only meet the growing high assurance and security requirements for waterway, but also play a significant advantage in improving transport efficiency, reducing costs, promoting energy conservation and so on. This study lays a solid foundation on realizing intelligent waterway and building a smooth, efficient, safe, green modern inland waterway system, and must be considered as an unavoidable problem for the coordinated development between "low carbon" transportation and social economic.

  14. Social Network Structures of Breast Cancer Patients and the Contributing Role of Patient Navigators.

    Science.gov (United States)

    Gunn, Christine M; Parker, Victoria A; Bak, Sharon M; Ko, Naomi; Nelson, Kerrie P; Battaglia, Tracy A

    2017-08-01

    Minority women in the U.S. continue to experience inferior breast cancer outcomes compared with white women, in part due to delays in care delivery. Emerging cancer care delivery models like patient navigation focus on social barriers, but evidence demonstrating how these models increase social capital is lacking. This pilot study describes the social networks of newly diagnosed breast cancer patients and explores the contributing role of patient navigators. Twenty-five women completed a one hour interview about their social networks related to cancer care support. Network metrics identified important structural attributes and influential individuals. Bivariate associations between network metrics, type of network, and whether the network included a navigator were measured. Secondary analyses explored associations between network structures and clinical outcomes. We identified three types of networks: kin-based, role and/or affect-based, or heterogeneous. Network metrics did not vary significantly by network type. There was a low prevalence of navigators included in the support networks (25%). Network density scores were significantly higher in those networks without a navigator. Network metrics were not predictive of clinical outcomes in multivariate models. Patient navigators were not frequently included in support networks, but provided distinctive types of support. If navigators can identify patients with poorly integrated (less dense) social networks, or who have unmet tangible support needs, the intensity of navigation services could be tailored. Services and systems that address gaps and variations in patient social networks should be explored for their potential to reduce cancer health disparities. This study used a new method to identify the breadth and strength of social support following a diagnosis of breast cancer, especially examining the role of patient navigators in providing support. While navigators were only included in one quarter of patient

  15. YARP-ROS Inter-Operation in a 2D Navigation Task

    Directory of Open Access Journals (Sweden)

    Marco Randazzo

    2018-02-01

    Full Text Available This paper presents some recent developments in YARP middleware, aimed to improve its integration with ROS. They include a new mechanism to read/write ROS transform frames and a new set of standard interfaces to intercommunicate with the ROS navigation stack. A novel set of YARP companion modules, which provide basic navigation functionalities for robots unable to run ROS, is also presented. These modules are optional, independent from each other, and they provide compatible functionalities to well-known packages available inside ROS framework. This paper also discusses how developers can customize their own hybrid YARP-ROS environment in the way it best suits their needs (e.g., the system can be configured to have a YARP application sending navigation commands to a ROS path planner, or vice versa. A number of available possibilities is presented through a set of chosen test cases applied to both real and simulated robots. Finally, example applications discussed in this paper are also made available to the community by providing snippets of code and links to source files hosted on github repository https://github.com/robotology.1

  16. Waste treatability guidance program. User's guide. Revision 0

    International Nuclear Information System (INIS)

    Toth, C.

    1995-01-01

    DOE sites across the country generate and manage radioactive, hazardous, mixed, and sanitary wastes. It is necessary for each site to find the technologies and associated capacities required to manage its waste. One role of DOE HQ Office of Environmental Restoration and Waste Management is to facilitate the integration of the site- specific plans into coherent national plans. DOE has developed a standard methodology for defining and categorizing waste streams into treatability groups based on characteristic parameters that influence waste management technology needs. This Waste Treatability Guidance Program automates the Guidance Document for the categorization of waste information into treatability groups; this application provides a consistent implementation of the methodology across the National TRU Program. This User's Guide provides instructions on how to use the program, including installations instructions and program operation. This document satisfies the requirements of the Software Quality Assurance Plan

  17. Getting Lost Through Navigation

    DEFF Research Database (Denmark)

    Debus, Michael S.

    2017-01-01

    In this presentation, I argued two things. First, that it is navigation that lies at the core of contemporary (3D-) videogames and that its analysis is of utmost importance. Second, that this analysis needs a more rigorous differentiation between specific acts of navigation. Considering the Oxford...... in videogames is a configurational rather than an interpretational one (Eskelinen 2001). Especially in the case of game spaces, navigation appears to be of importance (Wolf 2009; Flynn 2008). Further, it does not only play a crucial role for the games themselves, but also for the experience of the player...

  18. Lesions of the basal forebrain cholinergic system in mice disrupt idiothetic navigation.

    Directory of Open Access Journals (Sweden)

    Adam S Hamlin

    Full Text Available Loss of integrity of the basal forebrain cholinergic neurons is a consistent feature of Alzheimer's disease, and measurement of basal forebrain degeneration by magnetic resonance imaging is emerging as a sensitive diagnostic marker for prodromal disease. It is also known that Alzheimer's disease patients perform poorly on both real space and computerized cued (allothetic or uncued (idiothetic recall navigation tasks. Although the hippocampus is required for allothetic navigation, lesions of this region only mildly affect idiothetic navigation. Here we tested the hypothesis that the cholinergic medial septo-hippocampal circuit is important for idiothetic navigation. Basal forebrain cholinergic neurons were selectively lesioned in mice using the toxin saporin conjugated to a basal forebrain cholinergic neuronal marker, the p75 neurotrophin receptor. Control animals were able to learn and remember spatial information when tested on a modified version of the passive place avoidance test where all extramaze cues were removed, and animals had to rely on idiothetic signals. However, the exploratory behaviour of mice with cholinergic basal forebrain lesions was highly disorganized during this test. By contrast, the lesioned animals performed no differently from controls in tasks involving contextual fear conditioning and spatial working memory (Y maze, and displayed no deficits in potentially confounding behaviours such as motor performance, anxiety, or disturbed sleep/wake cycles. These data suggest that the basal forebrain cholinergic system plays a specific role in idiothetic navigation, a modality that is impaired early in Alzheimer's disease.

  19. Fully automatic guidance and control for rotorcraft nap-of-the-Earth flight following planned profiles. Volume 1: Real-time piloted simulation

    Science.gov (United States)

    Clement, Warren F.; Gorder, Peter J.; Jewell, Wayne F.

    1991-01-01

    Developing a single-pilot, all-weather nap-of-the-earth (NOE) capability requires fully automatic NOE (ANOE) navigation and flight control. Innovative guidance and control concepts are investigated in a four-fold research effort that: (1) organizes the on-board computer-based storage and real-time updating of NOE terrain profiles and obstacles in course-oriented coordinates indexed to the mission flight plan; (2) defines a class of automatic anticipative pursuit guidance algorithms and necessary data preview requirements to follow the vertical, lateral, and longitudinal guidance commands dictated by the updated flight profiles; (3) automates a decision-making process for unexpected obstacle avoidance; and (4) provides several rapid response maneuvers. Acquired knowledge from the sensed environment is correlated with the forehand knowledge of the recorded environment (terrain, cultural features, threats, and targets), which is then used to determine an appropriate evasive maneuver if a nonconformity of the sensed and recorded environments is observed. This four-fold research effort was evaluated in both fixed-based and moving-based real-time piloted simulations, thereby, providing a practical demonstration for evaluating pilot acceptance of the automated concepts, supervisory override, manual operation, and re-engagement of the automatic system. Volume one describes the major components of the guidance and control laws as well as the results of the piloted simulations. Volume two describes the complete mathematical model of the fully automatic guidance system for rotorcraft NOE flight following planned flight profiles.

  20. Doppler lidar sensor for precision navigation in GPS-deprived environment

    Science.gov (United States)

    Amzajerdian, F.; Pierrottet, D. F.; Hines, G. D.; Petway, L. B.; Barnes, B. W.

    2013-05-01

    Landing mission concepts that are being developed for exploration of solar system bodies are increasingly ambitious in their implementations and objectives. Most of these missions require accurate position and velocity data during their descent phase in order to ensure safe, soft landing at the pre-designated sites. Data from the vehicle's Inertial Measurement Unit will not be sufficient due to significant drift error after extended travel time in space. Therefore, an onboard sensor is required to provide the necessary data for landing in the GPS-deprived environment of space. For this reason, NASA Langley Research Center has been developing an advanced Doppler lidar sensor capable of providing accurate and reliable data suitable for operation in the highly constrained environment of space. The Doppler lidar transmits three laser beams in different directions toward the ground. The signal from each beam provides the platform velocity and range to the ground along the laser line-of-sight (LOS). The six LOS measurements are then combined in order to determine the three components of the vehicle velocity vector, and to accurately measure altitude and attitude angles relative to the local ground. These measurements are used by an autonomous Guidance, Navigation, and Control system to accurately navigate the vehicle from a few kilometers above the ground to the designated location and to execute a gentle touchdown. A prototype version of our lidar sensor has been completed for a closed-loop demonstration onboard a rocket-powered terrestrial free-flyer vehicle.

  1. The cerebellum: a new key structure in the navigation system

    Directory of Open Access Journals (Sweden)

    Christelle eRochefort

    2013-03-01

    Full Text Available Early investigations of cerebellar function focused on motor learning, in particular on eyeblink conditioning and adaptation of the vestibulo-ocular reflex, and led to the general view that cerebellar Long Term Depression (LTD at parallel fiber-Purkinje cell synapses is the neural correlate of cerebellar motor learning. Thereafter, while the full complexity of cerebellar plasticities was being unraveled, cerebellar involvement in more cognitive tasks - including spatial navigation - was further investigated. However, cerebellar implication in spatial navigation remains a matter of debate because motor deficits frequently associated with cerebellar damage often prevent the dissociation between its role in spatial cognition from its implication in motor function. Here, we review recent findings from behavioral and electrophysiological analyses of cerebellar mutant mouse models, which show that the cerebellum might participate in the construction of hippocampal spatial representation map (i.e. place cells and thereby in goal-directed navigation. These recent advances in cerebellar research point toward a model in which computation from the cerebellum could be required for spatial representation and would involve the integration of multi-source self-motion information to: 1 transform the reference frame of vestibular signals and 2 distinguish between self- and externally-generated vestibular signals. We eventually present herein anatomical and functional connectivity data supporting a cerebello-hippocampal interaction. Whilst a direct cerebello-hippocampal projection has been suggested, recent investigations rather favor a multi-synaptic pathway involving posterior parietal and retrosplenial cortices, two regions critically involved in spatial navigation.

  2. 78 FR 41304 - Navigation and Navigable Waters; Technical, Organizational, and Conforming Amendments; Correction

    Science.gov (United States)

    2013-07-10

    ... DEPARTMENT OF HOMELAND SECURITY Coast Guard 33 CFR Part 105 [Docket No. USCG-2013-0397] RIN 1625-AC06 Navigation and Navigable Waters; Technical, Organizational, and Conforming Amendments; Correction AGENCY: Coast Guard, DHS. ACTION: Final rule; correction. SUMMARY: The Coast Guard published a final rule...

  3. Restricted Navigation Areas - USACE IENC

    Data.gov (United States)

    Department of Homeland Security — These inland electronic Navigational charts (IENCs) were developed from available data used in maintenance of Navigation channels. Users of these IENCs should be...

  4. NFC Internal: An Indoor Navigation System

    Science.gov (United States)

    Ozdenizci, Busra; Coskun, Vedat; Ok, Kerem

    2015-01-01

    Indoor navigation systems have recently become a popular research field due to the lack of GPS signals indoors. Several indoors navigation systems have already been proposed in order to eliminate deficiencies; however each of them has several technical and usability limitations. In this study, we propose NFC Internal, a Near Field Communication (NFC)-based indoor navigation system, which enables users to navigate through a building or a complex by enabling a simple location update, simply by touching NFC tags those are spread around and orient users to the destination. In this paper, we initially present the system requirements, give the design details and study the viability of NFC Internal with a prototype application and a case study. Moreover, we evaluate the performance of the system and compare it with existing indoor navigation systems. It is seen that NFC Internal has considerable advantages and significant contributions to existing indoor navigation systems in terms of security and privacy, cost, performance, robustness, complexity, user preference and commercial availability. PMID:25825976

  5. Validation of severe accident management guidance for the wolsong plants

    International Nuclear Information System (INIS)

    Park, S. Y.; Jin, Y. H.; Kim, S. D.; Song, Y. M.

    2006-01-01

    Full text: Full text: The severe accident management(SAM) guidance has been developed for the Wolsong nuclear power plants in Korea. The Wolsong plants are 700MWe CANDU-type reactors with heavy water as the primary coolant, natural uranium-fueled pressurized, horizontal tubes, surrounded by heavy water moderator inside a horizontal calandria vessel. The guidance includes six individual accident management strategies: (1) injection into primary heat transport system (2) injection into calandria vessel (3) injection into calandria vault (4) reduction of fission product release (5) control of reactor building condition (6) reduction of reactor building hydrogen. The paper provides the approaches to validate the SAM guidance. The validation includes the evaluation of:(l) effectiveness of accident management strategies, (2) performance of mitigation systems or components, (3) calculation aids, (4) strategy control diagram, and (5) interface with emergency operation procedure and with radiation emergency plan. Several severe accident sequences with high probability is selected from the plant specific level 2 probabilistic safety analysis results for the validation of SAM guidance. Afterward, thermal hydraulic and severe accident phenomenological analyses is performed using ISAAC(Integrated Severe Accident Analysis Code for CANDU Plant) computer program. Furthermore, the experiences obtained from a table-top-drill is also discussed

  6. 75 FR 48564 - Navigation and Navigable Waters; Technical, Organizational, and Conforming Amendments, Sector...

    Science.gov (United States)

    2010-08-11

    ... DEPARTMENT OF HOMELAND SECURITY Coast Guard 33 CFR Parts 3 and 165 [Docket No. USCG-2010-0351] RIN 1625-ZA25 Navigation and Navigable Waters; Technical, Organizational, and Conforming Amendments, Sector Columbia River, WA AGENCY: Coast Guard, DHS. ACTION: Final rule. SUMMARY: This rule makes non-substantive...

  7. Inertial navigation sensor integrated motion analysis for autonomous vehicle navigation

    Science.gov (United States)

    Roberts, Barry; Bhanu, Bir

    1992-01-01

    Recent work on INS integrated motion analysis is described. Results were obtained with a maximally passive system of obstacle detection (OD) for ground-based vehicles and rotorcraft. The OD approach involves motion analysis of imagery acquired by a passive sensor in the course of vehicle travel to generate range measurements to world points within the sensor FOV. INS data and scene analysis results are used to enhance interest point selection, the matching of the interest points, and the subsequent motion-based computations, tracking, and OD. The most important lesson learned from the research described here is that the incorporation of inertial data into the motion analysis program greatly improves the analysis and makes the process more robust.

  8. Sex differences in navigation strategy and efficiency.

    Science.gov (United States)

    Boone, Alexander P; Gong, Xinyi; Hegarty, Mary

    2018-05-22

    Research on human navigation has indicated that males and females differ in self-reported navigation strategy as well as objective measures of navigation efficiency. In two experiments, we investigated sex differences in navigation strategy and efficiency using an objective measure of strategy, the dual-solution paradigm (DSP; Marchette, Bakker, & Shelton, 2011). Although navigation by shortcuts and learned routes were the primary strategies used in both experiments, as in previous research on the DSP, individuals also utilized route reversals and sometimes found the goal location as a result of wandering. Importantly, sex differences were found in measures of both route selection and navigation efficiency. In particular, males were more likely to take shortcuts and reached their goal location faster than females, while females were more likely to follow learned routes and wander. Self-report measures of strategy were only weakly correlated with objective measures of strategy, casting doubt on their usefulness. This research indicates that the sex difference in navigation efficiency is large, and only partially related to an individual's navigation strategy as measured by the dual-solution paradigm.

  9. Celestial Navigation in the USA, Fiji, and Tunisia

    Science.gov (United States)

    Holbrook, Jarita C.

    2015-05-01

    Today there are many coastal communities that are home to navigators who use stars for position finding at night; I was, however, unaware of this fact when I began researching celestial navigation practices in 1997. My project focused on three communities: the Moce Islanders of Fiji, the Kerkennah Islanders in Tunisia, and the U.S. Navy officers and students at the United States Naval Academy, Annapolis, Maryland. My goal was to answer the question of why people continue to navigate by the stars, but also to understand the role of technology in their navigation practices. Using anthropology techniques of ethnography including participant observation, formal and informal interviews, audio and videotaping, I gathered data over five years at the three communities. I began by learning the details of how they use the stars for navigation. Next, I learned about who did the navigation and where they learned to navigate. I gathered opinions on various navigation aids and instruments, and opinions about the future of using the stars for navigation. I listened to the stories that they told about navigating. In the United States I worked in English, in Fiji, in Fijian and English, and in Tunisia, French and English. For the formal interviews I worked with translators. The navigators use stars for navigating today but the future of their techniques is not certain. Though practiced today, these celestial navigation traditions have undergone and continue to undergo changes. New navigational technologies are part of the stimulation for change, thus 'a meeting of different worlds' is symbolized by peoples encounters with these technologies.

  10. Nautical Navigation Aids (NAVAID) Locations

    Data.gov (United States)

    Department of Homeland Security — Structures intended to assist a navigator to determine position or safe course, or to warn of dangers or obstructions to navigation. This dataset includes lights,...

  11. Effect of lateral deformations of guideway on guidance characteristics of maglev train

    International Nuclear Information System (INIS)

    Kim, Ki Jung; Yang, Seok Jo; Lee, Jae Kyoung; Han, Hyung Suk

    2015-01-01

    A slender guideway is essential in improving aesthetically and reducing its construction cost which accounts for about 70% of overall investment for maglev system. As the slender guideway, however, may increase its deformation, its effect on levitation stability and guidance performance needs to be analyzed. The purpose of this study is to analyze the effect on guidance characteristics of maglev due to the lateral deformation of the guideway girder and lateral irregularity of guiderail. For doing this, 3D model considering lateral deformation of girder and irregularity of rail of the guideway is developed. Using the dynamic interaction model integrated with the proposed guideway and maglev vehicle including electromagnetics and its controller, guidance characteristics of maglev are analyzed. It is analyzed that the effect on lateral deformation of girder is relatively small compared to deformation on the lateral irregularities of guiderail

  12. Effect of lateral deformations of guideway on guidance characteristics of maglev train

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ki Jung; Yang, Seok Jo [Dept. of Mechatronics Engineering, Chungnam National Unversity, Daejeon (Korea, Republic of); Lee, Jae Kyoung; Han, Hyung Suk [Korea Institute of Machery and Materials, Daejeon (Korea, Republic of)

    2015-11-15

    A slender guideway is essential in improving aesthetically and reducing its construction cost which accounts for about 70% of overall investment for maglev system. As the slender guideway, however, may increase its deformation, its effect on levitation stability and guidance performance needs to be analyzed. The purpose of this study is to analyze the effect on guidance characteristics of maglev due to the lateral deformation of the guideway girder and lateral irregularity of guiderail. For doing this, 3D model considering lateral deformation of girder and irregularity of rail of the guideway is developed. Using the dynamic interaction model integrated with the proposed guideway and maglev vehicle including electromagnetics and its controller, guidance characteristics of maglev are analyzed. It is analyzed that the effect on lateral deformation of girder is relatively small compared to deformation on the lateral irregularities of guiderail.

  13. Geographos asteroid flyby and autonomous navigation study

    Energy Technology Data Exchange (ETDEWEB)

    Ng, L.C.; Pines, D.J. [Lawrence Livermore National Lab., CA (United States); Patz, B.J.; Perron, D.C. [Coleman Research Corp., Orlando, FL (United States)

    1993-02-22

    Deep Space Program Science Experiment (DSPSE), also known as Clementine, is a collection of science experiments conducted in near-earth with the goal of demonstrating Strategic Defense Initiative Office (SDIO) developed technologies. The 785 lb (fully fueled) spacecraft will be launched into low Earth orbit in February 1994 together with a Star 37 solid kick motor and interstage. After orbit circulation using Clementine`s 110 lb Delta-V thruster, the Star 37 will execute a trans-lunar injection burn that will send the spacecraft toward lunar obit. The 110-lb will then be used in a sequence of burns to insert Clementine into a trimmed, polar orbit around the moon. After a two month moon mapping mission, Clementine will execute burns to leave lunar orbit, sling-shot around Earth, and flyby the moon on a 9.4 million km journey toward the asteroid Geographos. After about three months in transit, Clementine will attempt a flyby with a closest point of approach of 100 km from the asteroid on August 31, 1994. During its approach to Geographos, Clementine will be tracked by the Deep Space Network (DSN) and receive guidance updates. The last update and correction burn will occur about one day out of the flyby. Multiple experiments will be performed at key events during the mission that utilize Clementine`s SDIO-derived resources, including its Star Trackers, UV/Vis camera, infrared sensors (NWIR and LWIR), and high resolution laser radar (HIRes/LIDAR). In addition to the evaluation of SDIO algorithms and sensors, high resolution imagery will be obtained while the spacecraft is in Earth orbit, lunar obit and during the Geographos flyby. This paper describes the results of a study on the precision guidance, navigation, and intercept strategy for the flyby mission.

  14. An on-line monitoring system for navigation equipment

    Science.gov (United States)

    Wang, Bo; Yang, Ping; Liu, Jing; Yang, Zhengbo; Liang, Fei

    2017-10-01

    Civil air navigation equipment is the most important infrastructure of Civil Aviation, which is closely related to flight safety. In addition to regular flight inspection, navigation equipment's patrol measuring, maintenance measuring, running measuring under special weather conditions are the important means of ensuring aviation flight safety. According to the safety maintenance requirements of Civil Aviation Air Traffic Control navigation equipment, this paper developed one on-line monitoring system with independent intellectual property rights for navigation equipment, the system breakthroughs the key technologies of measuring navigation equipment on-line including Instrument Landing System (ILS) and VHF Omni-directional Range (VOR), which also meets the requirements of navigation equipment ground measurement set by the ICAO DOC 8071, it provides technical means of the ground on-line measurement for navigation equipment, improves the safety of navigation equipment operation, and reduces the impact of measuring navigation equipment on airport operation.

  15. 32 CFR 644.3 - Navigation Projects.

    Science.gov (United States)

    2010-07-01

    ... 32 National Defense 4 2010-07-01 2010-07-01 true Navigation Projects. 644.3 Section 644.3 National... HANDBOOK Project Planning Civil Works § 644.3 Navigation Projects. (a) Land to be acquired in fee. All... construction and borrow areas. (3) In navigation-only projects, the right to permanently flood should be...

  16. 14 CFR 121.349 - Communication and navigation equipment for operations under VFR over routes not navigated by...

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Communication and navigation equipment for... § 121.349 Communication and navigation equipment for operations under VFR over routes not navigated by... receiver providing visual and aural signals; and (iii) One ILS receiver; and (3) Any RNAV system used to...

  17. Quantum imaging for underwater arctic navigation

    Science.gov (United States)

    Lanzagorta, Marco

    2017-05-01

    The precise navigation of underwater vehicles is a difficult task due to the challenges imposed by the variable oceanic environment. It is particularly difficult if the underwater vehicle is trying to navigate under the Arctic ice shelf. Indeed, in this scenario traditional navigation devices such as GPS, compasses and gyrocompasses are unavailable or unreliable. In addition, the shape and thickness of the ice shelf is variable throughout the year. Current Arctic underwater navigation systems include sonar arrays to detect the proximity to the ice. However, these systems are undesirable in a wartime environment, as the sound gives away the position of the underwater vehicle. In this paper we briefly describe the theoretical design of a quantum imaging system that could allow the safe and stealthy navigation of underwater Arctic vehicles.

  18. Integrated Systems Engineering Framework (ISEF)

    Data.gov (United States)

    Federal Laboratory Consortium — The ISEF is an integrated SE framework built to create and capture knowledge using a decision-centric method, high-quality data visualizations, intuitive navigation...

  19. Autonomous Robot Navigation based on Visual Landmarks

    DEFF Research Database (Denmark)

    Livatino, Salvatore

    2005-01-01

    The use of landmarks for robot navigation is a popular alternative to having a geometrical model of the environment through which to navigate and monitor self-localization. If the landmarks are defined as special visual structures already in the environment then we have the possibility of fully a...... automatically learn and store visual landmarks, and later recognize these landmarks from arbitrary positions and thus estimate robot position and heading.......The use of landmarks for robot navigation is a popular alternative to having a geometrical model of the environment through which to navigate and monitor self-localization. If the landmarks are defined as special visual structures already in the environment then we have the possibility of fully...... autonomous navigation and self-localization using automatically selected landmarks. The thesis investigates autonomous robot navigation and proposes a new method which benefits from the potential of the visual sensor to provide accuracy and reliability to the navigation process while relying on naturally...

  20. Teaching Tool for a Control Systems Laboratory Using a Quadrotor as a Plant in MATLAB

    Science.gov (United States)

    Khan, Subhan; Jaffery, Mujtaba Hussain; Hanif, Athar; Asif, Muhammad Rizwan

    2017-01-01

    This paper presents a MATLAB-based application to teach the guidance, navigation, and control concepts of a quadrotor to undergraduate students, using a graphical user interface (GUI) and 3-D animations. The Simulink quadrotor model is controlled by a proportional integral derivative controller and a linear quadratic regulator controller. The GUI…