WorldWideScience

Sample records for radio navigation systems

  1. 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.

  2. Reliable Location-Based Services from Radio Navigation Systems

    Directory of Open Access Journals (Sweden)

    Per Enge

    2010-12-01

    Full Text Available Loran is a radio-based navigation system originally designed for naval applications. We show that Loran-C’s high-power and high repeatable accuracy are fantastic for security applications. First, we show how to derive a precise location tag—with a sensitivity of about 20 meters—that is difficult to project to an exact location. A device can use our location tag to block or allow certain actions, without knowing its precise location. To ensure that our tag is reproducible we make use of fuzzy extractors, a mechanism originally designed for biometric authentication. We build a fuzzy extractor specifically designed for radio-type errors and give experimental evidence to show its effectiveness. Second, we show that our location tag is difficult to predict from a distance. For example, an observer cannot predict the location tag inside a guarded data center from a few hundreds of meters away. As an application, consider a location-aware disk drive that will only work inside the data center. An attacker who steals the device and is capable of spoofing Loran-C signals, still cannot make the device work since he does not know what location tag to spoof. We provide experimental data supporting our unpredictability claim.

  3. Flight Test Result for the Ground-Based Radio Navigation System Sensor with an Unmanned Air Vehicle.

    Science.gov (United States)

    Jang, Jaegyu; Ahn, Woo-Guen; Seo, Seungwoo; Lee, Jang Yong; Park, Jun-Pyo

    2015-11-11

    The Ground-based Radio Navigation System (GRNS) is an alternative/backup navigation system based on time synchronized pseudolites. It has been studied for some years due to the potential vulnerability issue of satellite navigation systems (e.g., GPS or Galileo). In the framework of our study, a periodic pulsed sequence was used instead of the randomized pulse sequence recommended as the RTCM (radio technical commission for maritime services) SC (special committee)-104 pseudolite signal, as a randomized pulse sequence with a long dwell time is not suitable for applications requiring high dynamics. This paper introduces a mathematical model of the post-correlation output in a navigation sensor, showing that the aliasing caused by the additional frequency term of a periodic pulsed signal leads to a false lock (i.e., Doppler frequency bias) during the signal acquisition process or in the carrier tracking loop of the navigation sensor. We suggest algorithms to resolve the frequency false lock issue in this paper, relying on the use of a multi-correlator. A flight test with an unmanned helicopter was conducted to verify the implemented navigation sensor. The results of this analysis show that there were no false locks during the flight test and that outliers stem from bad dilution of precision (DOP) or fluctuations in the received signal quality.

  4. HARDWARE AND ALGORITHMIC STRUCTURE OF MULTIPOSITION RADIO RANGEFINDING NAVIGATION AND LANDING AERO-SYSTEM

    Directory of Open Access Journals (Sweden)

    Yaroslav Kondrashov

    2011-03-01

    Full Text Available Abstract. The principles of formation of the structure and functioning algorithms are developed andpresented for multipositioning radio rangefinding land-based system which identifies the location ofcommuter aircrafts in the vertical and horizontal planes by the method of three ranges without usingaltimeter.Keywords: aircraft, commuter airlines, aeronavigation, landing, airborne radio ranging equipment,operation algorithms.

  5. Portable Wireless Device Threat Assessment for Aircraft Navigation Radios

    Science.gov (United States)

    Nguyen, Truong X.; Koppen, Sandra V.; Ely, Jay J.; Williams, Reuben A.; Smith, Laura J.; Salud, Maria Theresa P.

    2004-01-01

    This paper addresses the concern for Wireless Local Area Network devices and two-way radios to cause electromagnetic interference to aircraft navigation radio systems. Spurious radiated emissions from various IEEE 802.11a, 802.11b, and Bluetooth devices are characterized using reverberation chambers. The results are compared with baseline emissions from standard laptop computer and personal digital assistants (PDAs) that are currently allowed for use on aircraft. The results indicate that the WLAN devices tested are not more of a threat to aircraft navigation radios than standard laptop computers and PDAs in most aircraft bands. In addition, spurious radiated emission data from seven pairs of two-way radios are provided. These two-way radios emit at much higher levels in the bands considered. A description of the measurement process, device modes of operation and the measurement results are reported.

  6. 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.

  7. Tracking radioactive shipments using radio-navigation and satellite telecommunication systems

    International Nuclear Information System (INIS)

    Harmon, L.H.; Habib, E.J.; Hurley, J.D.; Carlson, R.D.

    1988-01-01

    The United States Department of Enegy (USDOE) Waste Transportation Management Division (WMTD) has commissioned the development of a transportation tracking management and communication system to monitor movement of radioactive material shipments throughout the United States. The system, TRANSCOM, is being developed to enhance DOE's management oversight and operational control over the transport of sensitive materials (e.g., spent fuel, highlevel waste, transuranic waste etc.) and to address state and local government concerns regarding public safety. These goals are accomplished through providing a near real time tracking and communication system complete with information database management to support emergency response capabilities

  8. 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

  9. Radio Engineering System of Short-Range Navigation. RSBN-2. Part I. (Radioteknicheskaya Sistema Blizhney Navigatsii RSBN-2)

    Science.gov (United States)

    1977-02-09

    RANGE NAVIGATION. RSBN-2 By: Ye. M. Yakovlev, A. N. Kleplkov, et al. English pages: 706 source: Radlotekhnlcheskaya Sistema Bllzhney Navigatsli...L4 and the grid of tube L5 (6N8S) limits grid m^^mammm^m^^^f.^^ rn .„ | -.,, ..S^JTv i tOC = 77050017 PAGE ^ I current©. |: *■ «a—m

  10. Space Telecommunications Radio System STRS Cognitive Radio

    Science.gov (United States)

    Briones, Janette C.; Handler, Louis M.

    2013-01-01

    Radios today are evolving from awareness toward cognition. A software defined radio (SDR) provides the most capability for integrating autonomic decision making ability and allows the incremental evolution toward a cognitive radio. This cognitive radio technology will impact NASA space communications in areas such as spectrum utilization, interoperability, network operations, and radio resource management over a wide range of operating conditions. NASAs cognitive radio will build upon the infrastructure being developed by Space Telecommunication Radio System (STRS) SDR technology. This paper explores the feasibility of inserting cognitive capabilities in the NASA STRS architecture and the interfaces between the cognitive engine and the STRS radio. The STRS architecture defines methods that can inform the cognitive engine about the radio environment so that the cognitive engine can learn autonomously from experience, and take appropriate actions to adapt the radio operating characteristics and optimize performance.

  11. 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.

  12. MODELING OF HARDWARE AND ALGORITHMIC STRUCTURE OF MOBILE MULTIPOSITIONING RADIO RANGEFINDING NAVIGATION AND LANDING AEROSYSTEM IN ITS SPATIAL CONFIGURATION

    Directory of Open Access Journals (Sweden)

    Ya. V. Kondrashov

    2014-01-01

    Full Text Available The concept of structuring of radio equipment, mathematical and algorithmic tools to provide computing operations for determining the location of aircraft in spatial configuration of mobile (portable multipositioning radio rangefinding interrogation-reply navigation and landing system is considered in this article. The mathematical modeling of algorithms of aircraft traffic terminal control is carried out. The results of calculations of potential system performance and its analysis for compliance with international safety requirements are represented.

  13. 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.

  14. 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].

  15. Development of field navigation system; Field navigation system no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Ibara, S; Minode, M; Nishioka, K [Daihatsu Motor Co. Ltd., Osaka (Japan)

    1995-04-20

    This paper describes the following matters on a field navigation system developed for the purpose of covering a field of several kilometer square. This system consists of a center system and a vehicle system, and the center system comprises a map information computer and a communication data controlling computer; since the accuracy for a vehicle position detected by a GPS is not sufficient, an attempt of increasing the accuracy of vehicle position detection is made by means of a hybrid system; the hybrid system uses a satellite navigation method of differential system in which the error components in the GPS are transmitted from the center, and also uses a self-contained navigation method which performs an auxiliary function when the accuracy in the GPS has dropped; corrected GPS values, emergency messages to all of the vehicles and data of each vehicle position are communicated by wireless transmission in two ways between the center and vehicles; and accommodation of the map data adopted a system that can respond quickly to any change in roads and facilities. 3 refs., 13 figs., 1 tab.

  16. 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

  17. Navigation system for interstitial brachytherapy

    International Nuclear Information System (INIS)

    Strassmann, G.; Kolotas, C.; Heyd, R.

    2000-01-01

    The purpose of the stud was to develop a computed tomography (CT) based electromagnetic navigation system for interstitial brachytherapy. This is especially designed for situations when needles have to be positioned adjacent to or within critical anatomical structures. In such instances interactive 3D visualisation of the needle positions is essential. The material consisted of a Polhemus electromagnetic 3D digitizer, a Pentium 200 MHz laptop and a voice recognition for continuous speech. In addition, we developed an external reference system constructed of Perspex which could be positioned above the tumour region and attached to the patient using a non-invasive fixation method. A specially designed needle holder and patient bed were also developed. Measurements were made on a series of phantoms in order to study the efficacy and accuracy of the navigation system. The mean navigation accuracy of positioning the 20.0 cm length metallic needles within the phantoms was in the range 2.0-4.1 mm with a maximum of 5.4 mm. This is an improvement on the accuracy of a CT-guided technique which was in the range 6.1-11.3 mm with a maximum of 19.4 mm. The mean reconstruction accuracy of the implant geometry was 3.2 mm within a non-ferromagnetic environment. We found that although the needles were metallic this did not have a significant influence. We also found for our experimental setups that the CT table and operation table non-ferromagnetic parts had no significant influence on the navigation accuracy. This navigation system will be a very useful clinical tool for interstitial brachytherapy applications, particularly when critical structures have to be avoided. It also should provide a significant improvement on our existing technique

  18. Spectrum management and radio resource management considering cognitive radio systems

    NARCIS (Netherlands)

    Haartsen, J.C.; Wieweg, Lasse; Huschke, Jörg

    2005-01-01

    International fora and some national administrations define a cognitive radio (CR) as a pioneering radio communication system that would be capable of altering and adapting its transmitter and receiver parameters based on communication and the exchange of information with related detectable radio

  19. 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.

  20. Airports and Navigation Aids Database System -

    Data.gov (United States)

    Department of Transportation — Airport and Navigation Aids Database System is the repository of aeronautical data related to airports, runways, lighting, NAVAID and their components, obstacles, no...

  1. Wireless Phone Threat Assessment for Aircraft Communication and Navigation Radios

    Science.gov (United States)

    Nguyens, T. X.; Koppen, S. V.; Smith, L. J.; Williams, R. A.; Salud, M. T.

    2005-01-01

    Emissions in aircraft communication and navigation bands are measured for the latest generation of wireless phones. The two wireless technologies considered, GSM/GPRS and CDMA2000, are the latest available to general consumers in the U.S. A base-station simulator is used to control the phones. The measurements are conducted using reverberation chambers, and the results are compared against FCC and aircraft installed equipment emission limits. The results are also compared against baseline emissions from laptop computers and personal digital assistant devices that are currently allowed to operate on aircraft.

  2. Electromagnetic Interference Assessment of CDMA and GSM Wireless Phones to Aircraft Navigation Radios

    Science.gov (United States)

    Ely, Jay J.; Nguyen, Truong X.; Koppen, Sandra V.; Salud, M. Theresa

    2002-01-01

    To address the concern for cellular phone electromagnetic interference (EMI) to aircraft radios, a radiated emission measurement process for CDMA (IS-95) and GSM (ETSI GSM 11.22) wireless handsets was developed. Spurious radiated emissions were efficiently characterized from devices tested in either a semi-anechoic or reverberation chamber, in terms of effective isotropic radiated power. Eight representative handsets (4 GSM, 4 CDMA) were commanded to operate while varying their radio transmitter parameters (power, modulation, etc.). This report provides a detailed description of the measurement process and resulting data, which may subsequently be used by others as a basis of consistent evaluation for cellular/PCS phones, Bluetooth, IEEE802.11b, IEEE802.11a, FRS/GMRS radios, and other portable transmitters. Aircraft interference path loss (IPL) and navigation radio interference threshold data from numerous reference documents, standards, and NASA partnerships were compiled. Using this data, a preliminary risk assessment is provided for CDMA and GSM wireless phone interference to aircraft localizer, Glideslope, VOR, and GPS radio receivers on typical transport airplanes. The report identifies where existing data for device emissions, IPL, and navigation radio interference thresholds needs to be extended for an accurate risk assessment for wireless transmitters in aircraft.

  3. Autonomous navigation system and method

    Science.gov (United States)

    Bruemmer, David J [Idaho Falls, ID; Few, Douglas A [Idaho Falls, ID

    2009-09-08

    A robot platform includes perceptors, locomotors, and a system controller, which executes instructions for autonomously navigating a robot. The instructions repeat, on each iteration through an event timing loop, the acts of defining an event horizon based on the robot's current velocity, detecting a range to obstacles around the robot, testing for an event horizon intrusion by determining if any range to the obstacles is within the event horizon, and adjusting rotational and translational velocity of the robot accordingly. If the event horizon intrusion occurs, rotational velocity is modified by a proportion of the current rotational velocity reduced by a proportion of the range to the nearest obstacle and translational velocity is modified by a proportion of the range to the nearest obstacle. If no event horizon intrusion occurs, translational velocity is set as a ratio of a speed factor relative to a maximum speed.

  4. Hybrid spread spectrum radio system

    Science.gov (United States)

    Smith, Stephen F [London, TN; Dress, William B [Camas, WA

    2010-02-09

    Systems and methods are described for hybrid spread spectrum radio systems. A method, includes receiving a hybrid spread spectrum signal including: fast frequency hopping demodulating and direct sequence demodulating a direct sequence spread spectrum signal, wherein multiple frequency hops occur within a single data-bit time and each bit is represented by chip transmissions at multiple frequencies.

  5. Space Telecommunications Radio System (STRS) Architecture. Part 1; Tutorial - Overview

    Science.gov (United States)

    Handler, Louis M.; Briones, Janette C.; Mortensen, Dale J.; Reinhart, Richard C.

    2012-01-01

    Space Telecommunications Radio System (STRS) Architecture Standard provides a NASA standard for software-defined radio. STRS is being demonstrated in the Space Communications and Navigation (SCaN) Testbed formerly known as Communications, Navigation and Networking Configurable Testbed (CoNNeCT). Ground station radios communicating the SCaN testbed are also being written to comply with the STRS architecture. The STRS Architecture Tutorial Overview presents a general introduction to the STRS architecture standard developed at the NASA Glenn Research Center (GRC), addresses frequently asked questions, and clarifies methods of implementing the standard. The STRS architecture should be used as a base for many of NASA s future telecommunications technologies. The presentation will provide a basic understanding of STRS.

  6. Spacecraft navigation at Mars using earth-based and in situ radio tracking techniques

    Science.gov (United States)

    Thurman, S. W.; Edwards, C. D.; Kahn, R. D.; Vijayaraghavan, A.; Hastrup, R. C.; Cesarone, R. J.

    1992-08-01

    A survey of earth-based and in situ radiometric data types and results from a number of studies investigating potential radio navigation performance for spacecraft approaching/orbiting Mars and for landed spacecraft and rovers on the surface of Mars are presented. The performance of Doppler, ranging and interferometry earth-based data types involving single or multiple spacecraft is addressed. This evaluation is conducted with that of in situ data types, such as Doppler and ranging measurements between two spacecraft near Mars, or between a spacecraft and one or more surface radio beacons.

  7. 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...

  8. Radio frequency system

    Energy Technology Data Exchange (ETDEWEB)

    Basu Mallik, D N; Bhattacharya, D S; Khemka, P K; Kar, K K; Rao, C B.S.; Thatte, A P

    1977-09-01

    The RF system of the variable energy cyclotron at Calcutta mainly consists of the dee, the dee stem, the fixed and moving panels, all enclosed in a vacuum-light enclosure called the resonator tank. The system can be tuned in the range 5.5 MHz to 16.5 MHz. The different parts of the resonant system including the RF oscillator are described.

  9. The radio frequency system

    International Nuclear Information System (INIS)

    Basu Mallik, D.N.; Bhattacharya, D.S.; Khemka, P.K.; Kar, K.K.; Rao, C.B.S.; Thatte, A.P.

    1977-01-01

    The RF system of the variable energy cyclotron at Calcutta mainly consists of the dee, the dee stem, the fixed and moving panels, all enclosed in a vacuum-light enclosure called the resonator tank. The system can be tuned in the range 5.5 MHz to 16.5 MHz. The different parts of the resonant system including the RF oscillator are described. (A.K.)

  10. Reconfigurable radio systems network architectures and standards

    CERN Document Server

    Iacobucci, Maria Stella

    2013-01-01

    This timely book provides a standards-based view of the development, evolution, techniques and potential future scenarios for the deployment of reconfigurable radio systems.  After an introduction to radiomobile and radio systems deployed in the access network, the book describes cognitive radio concepts and capabilities, which are the basis for reconfigurable radio systems.  The self-organizing network features introduced in 3GPP standards are discussed and IEEE 802.22, the first standard based on cognitive radio, is described. Then the ETSI reconfigurable radio systems functional ar

  11. ITER radio frequency systems

    International Nuclear Information System (INIS)

    Bosia, G.

    1998-01-01

    Neutral Beam Injection and RF heating are two of the methods for heating and current drive in ITER. The three ITER RF systems, which have been developed during the EDA, offer several complementary services and are able to fulfil ITER operational requirements

  12. Global Positioning System Navigation Algorithms

    Science.gov (United States)

    1977-05-01

    Historical Remarks on Navigation In Greek mythology , Odysseus sailed safely by the Sirens only to encounter the monsters Scylla and Charybdis...TNED 000 00 1(.7 BIBLIOGRAPHY 1. Pinsent, John. Greek Mythology . Paul Hamlyn, London, 1969. 2. Kline, Morris. Mathematical Thought from Ancient to

  13. Smart parking management and navigation system

    KAUST Repository

    Saadeldin, Mohamed

    2017-01-01

    Various examples are provided for smart parking management, which can include navigation. In one example, a system includes a base station controller configured to: receive a wireless signal from a parking controller located at a parking space

  14. 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

  15. 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

  16. NFC Internal: An Indoor Navigation System

    Directory of Open Access Journals (Sweden)

    Busra Ozdenizci

    2015-03-01

    Full Text Available 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.

  17. Radio frequency integrated circuit design for cognitive radio systems

    CERN Document Server

    Fahim, Amr

    2015-01-01

    This book fills a disconnect in the literature between Cognitive Radio systems and a detailed account of the circuit implementation and architectures required to implement such systems.  Throughout the book, requirements and constraints imposed by cognitive radio systems are emphasized when discussing the circuit implementation details.  In addition, this book details several novel concepts that advance state-of-the-art cognitive radio systems.  This is a valuable reference for anybody with background in analog and radio frequency (RF) integrated circuit design, needing to learn more about integrated circuits requirements and implementation for cognitive radio systems. ·         Describes in detail cognitive radio systems, as well as the circuit implementation and architectures required to implement them; ·         Serves as an excellent reference to state-of-the-art wideband transceiver design; ·         Emphasizes practical requirements and constraints imposed by cognitive radi...

  18. Contribution Towards Practical Cognitive Radios Systems

    KAUST Repository

    Ben Ghorbel, Mahdi

    2013-01-01

    to cognitive radio systems while taking into account practical constraints. Cogni- tive radios requires a capability to detect spectrum holes (spectrum sensing) and a scheduling flexibility to avoid the occupied spectrum and selectively use the empty spectrum

  19. HF radio systems and circuits

    CERN Document Server

    Sabin, William

    1998-01-01

    A comprehensive reference for the design of high frequency communications systems and equipment. This revised edition is loaded with practical data, much of which cannot be found in other reference books. Its approach to the subject follows the needs of an engineer from system definition and performance requirements down to the individual circuit elements that make up radio transmitters and receivers. The accompanying disk contains updated software on filters, matching networks and receiver analysis. SciTech Publishing also provides many other products related to Communication Systems Design.

  20. 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

  1. Navigation of robotic system using cricket motes

    Science.gov (United States)

    Patil, Yogendra J.; Baine, Nicholas A.; Rattan, Kuldip S.

    2011-06-01

    This paper presents a novel algorithm for self-mapping of the cricket motes that can be used for indoor navigation of autonomous robotic systems. The cricket system is a wireless sensor network that can provide indoor localization service to its user via acoustic ranging techniques. The behavior of the ultrasonic transducer on the cricket mote is studied and the regions where satisfactorily distance measurements can be obtained are recorded. Placing the motes in these regions results fine-grain mapping of the cricket motes. Trilateration is used to obtain a rigid coordinate system, but is insufficient if the network is to be used for navigation. A modified SLAM algorithm is applied to overcome the shortcomings of trilateration. Finally, the self-mapped cricket motes can be used for navigation of autonomous robotic systems in an indoor location.

  2. Reconfigurable EVA Radio with Built-In Navigation Capability, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Intelligent Automation, Inc. and its sub-contractor, Purdue University, propose to develop a power-efficient miniaturized reconfigurable EVA radio system with...

  3. Radio systems engineering a tutorial approach

    CERN Document Server

    Santos, Héctor J De Los; Ponte, Juan

    2015-01-01

    This book is intended for readers who already have knowledge of devices and circuits for radio-frequency (RF) and microwave communication and are ready to study the systems engineering-level aspects of modern radio communications systems. The authors provide a general overview of radio systems with their components, focusing on the analog parts of the system and their non-idealities. Based on the physical functionality of the various building blocks of a modern radio system, block parameters are derived, which allows the examination of their influence on the overall system performance. The dis

  4. 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

  5. 47 CFR 32.2231 - Radio systems.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Radio systems. 32.2231 Section 32.2231 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES UNIFORM SYSTEM OF ACCOUNTS FOR TELECOMMUNICATIONS COMPANIES Instructions for Balance Sheet Accounts § 32.2231 Radio systems. (a...

  6. Neurosurgical robotic arm drilling navigation system.

    Science.gov (United States)

    Lin, Chung-Chih; Lin, Hsin-Cheng; Lee, Wen-Yo; Lee, Shih-Tseng; Wu, Chieh-Tsai

    2017-09-01

    The aim of this work was to develop a neurosurgical robotic arm drilling navigation system that provides assistance throughout the complete bone drilling process. The system comprised neurosurgical robotic arm navigation combining robotic and surgical navigation, 3D medical imaging based surgical planning that could identify lesion location and plan the surgical path on 3D images, and automatic bone drilling control that would stop drilling when the bone was to be drilled-through. Three kinds of experiment were designed. The average positioning error deduced from 3D images of the robotic arm was 0.502 ± 0.069 mm. The correlation between automatically and manually planned paths was 0.975. The average distance error between automatically planned paths and risky zones was 0.279 ± 0.401 mm. The drilling auto-stopping algorithm had 0.00% unstopped cases (26.32% in control group 1) and 70.53% non-drilled-through cases (8.42% and 4.21% in control groups 1 and 2). The system may be useful for neurosurgical robotic arm drilling navigation. Copyright © 2016 John Wiley & Sons, Ltd.

  7. 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.

  8. Portable Integrated Wireless Device Threat Assessment to Aircraft Radio Systems

    Science.gov (United States)

    Salud, Maria Theresa P.; Williams, Reuben A. (Technical Monitor)

    2004-01-01

    An assessment was conducted on multiple wireless local area network (WLAN) devices using the three wireless standards for spurious radiated emissions to determine their threat to aircraft radio navigation systems. The measurement process, data and analysis are provided for devices tested using IEEE 802.11a, IEEE 802.11b, and Bluetooth as well as data from portable laptops/tablet PCs and PDAs (grouping known as PEDs). A comparison was made between wireless LAN devices and portable electronic devices. Spurious radiated emissions were investigated in the radio frequency bands for the following aircraft systems: Instrument Landing System Localizer and Glideslope, Very High Frequency (VHF) Communication, VHF Omnidirectional Range, Traffic Collision Avoidance System, Air Traffic Control Radar Beacon System, Microwave Landing System and Global Positioning System. Since several of the contiguous navigation systems were grouped under one encompassing measurement frequency band, there were five measurement frequency bands where spurious radiated emissions data were collected for the PEDs and WLAN devices. The report also provides a comparison between emissions data and regulatory emission limit.

  9. 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.

  10. Radio frequency system for nuclear fusion

    International Nuclear Information System (INIS)

    Kozeki, Shoichiro; Sagawa, Norimoto; Takizawa, Teruhiro

    1987-01-01

    The importance of radio frequency waves has been increasing in the area of nuclear fusion since they are indispensable for heating of plasma, etc. This report outlines radio frequency techniques used for nuclear fusion and describes the development of radio frequency systems (radio frequency plasma heating system and current drive system). Presently, in-depth studies are underway at various research institutes to achieve plasma heating by injection of radio frequency electric power. Three ranges of frequencies, ICRF (ion cyclotron range of frequency), LHRF (lower hybrid range of frequency) and ECRF (electron cyclotron range of frequency), are considered promissing for radio frequency heating. Candidate waves for plasma current driving include ECW (electron cyclotron wave), LHW (lower hybrid wave), MSW (magnetic sound wave), ICW (ion cyclotron wave) with minority component, and FW (fast wave). FW is the greatest in terms of current drive efficiency. In general, a radio frequency system for nuclear fusion consists of a radio frequency power source, transmission/matching circuit component and plasma connection component. (Nogami, K.)

  11. Adaptive OFDM System Design For Cognitive Radio

    NARCIS (Netherlands)

    Zhang, Q.; Kokkeler, Andre B.J.; Smit, Gerardus Johannes Maria

    2006-01-01

    Recently, Cognitive Radio has been proposed as a promising technology to improve spectrum utilization. A highly flexible OFDM system is considered to be a good candidate for the Cognitive Radio baseband processing where individual carriers can be switched off for frequencies occupied by a licensed

  12. Navigation System of Marks 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...

  13. ANALYSIS OF FREE ROUTE AIRSPACE AND PERFORMANCE BASED NAVIGATION IMPLEMENTATION IN THE EUROPEAN AIR NAVIGATION SYSTEM

    Directory of Open Access Journals (Sweden)

    Svetlana Pavlova

    2014-12-01

    Full Text Available European Air Traffic Management system requires continuous improvements as air traffic is increasingday by day. For this purpose it was developed by international organizations Free Route Airspace and PerformanceBased Navigation concepts that allow to offer a required level of safety, capacity, environmental performance alongwith cost-effectiveness. The aim of the article is to provide detailed analysis of Free Route Airspace and PerformanceBased Navigation implementation status within European region including Ukrainian air navigation system.

  14. Fiber optic gyroscopes for vehicle navigation systems

    Science.gov (United States)

    Kumagai, Tatsuya; Soekawa, Hirokazu; Yuhara, Toshiya; Kajioka, Hiroshi; Oho, Shigeru; Sonobe, Hisao

    1994-03-01

    Fiber optic gyroscopes (FOGs) have been developed for vehicle navigation systems and are used in Toyota Motor Corporation models Mark II, Chaser and Cresta in Japan. Use of FOGs in these systems requires high reliability under a wide range of conditions, especially in a temperature range between -40 and 85 degree(s)C. In addition, a high cost-performance ratio is needed. We have developed optical and electrical systems that are inexpensive and can perform well. They are ready to be mass-produced. FOGs have already been installed in luxury automobiles, and will soon be included in more basic vehicles. We have developed more inexpensive FOGs for this purpose.

  15. Hybrid cognitive engine for radio systems adaptation

    KAUST Repository

    Alqerm, Ismail

    2017-07-20

    Network efficiency and proper utilization of its resources are essential requirements to operate wireless networks in an optimal fashion. Cognitive radio aims to fulfill these requirements by exploiting artificial intelligence techniques to create an entity called cognitive engine. Cognitive engine exploits awareness about the surrounding radio environment to optimize the use of radio resources and adapt relevant transmission parameters. In this paper, we propose a hybrid cognitive engine that employs Case Based Reasoning (CBR) and Decision Trees (DTs) to perform radio adaptation in multi-carriers wireless networks. The engine complexity is reduced by employing DTs to improve the indexing methodology used in CBR cases retrieval. The performance of our hybrid engine is validated using software defined radios implementation and simulation in multi-carrier environment. The system throughput, signal to noise and interference ratio, and packet error rate are obtained and compared with other schemes in different scenarios.

  16. 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...

  17. Optical surgical navigation system causes pulse oximeter malfunction.

    Science.gov (United States)

    Satoh, Masaaki; Hara, Tetsuhito; Tamai, Kenji; Shiba, Juntaro; Hotta, Kunihisa; Takeuchi, Mamoru; Watanabe, Eiju

    2015-01-01

    An optical surgical navigation system is used as a navigator to facilitate surgical approaches, and pulse oximeters provide valuable information for anesthetic management. However, saw-tooth waves on the monitor of a pulse oximeter and the inability of the pulse oximeter to accurately record the saturation of a percutaneous artery were observed when a surgeon started an optical navigation system. The current case is thought to be the first report of this navigation system interfering with pulse oximetry. The causes of pulse jamming and how to manage an optical navigation system are discussed.

  18. Hybrid cognitive engine for radio systems adaptation

    KAUST Repository

    Alqerm, Ismail; Shihada, Basem

    2017-01-01

    of our hybrid engine is validated using software defined radios implementation and simulation in multi-carrier environment. The system throughput, signal to noise and interference ratio, and packet error rate are obtained and compared with other schemes

  19. Design, Development and Pre-Flight Testing of the Communications, Navigation, and Networking Reconfigurable Testbed (Connect) to Investigate Software Defined Radio Architecture on the International Space Station

    Science.gov (United States)

    Over, Ann P.; Barrett, Michael J.; Reinhart, Richard C.; Free, James M.; Cikanek, Harry A., III

    2011-01-01

    The Communication Navigation and Networking Reconfigurable Testbed (CoNNeCT) is a NASA-sponsored mission, which will investigate the usage of Software Defined Radios (SDRs) as a multi-function communication system for space missions. A softwaredefined radio system is a communication system in which typical components of the system (e.g., modulators) are incorporated into software. The software-defined capability allows flexibility and experimentation in different modulation, coding and other parameters to understand their effects on performance. This flexibility builds inherent redundancy and flexibility into the system for improved operational efficiency, real-time changes to space missions and enhanced reliability/redundancy. The CoNNeCT Project is a collaboration between industrial radio providers and NASA. The industrial radio providers are providing the SDRs and NASA is designing, building and testing the entire flight system. The flight system will be integrated on the Express Logistics Carrier (ELC) on the International Space Station (ISS) after launch on the H-IIB Transfer Vehicle in 2012. This paper provides an overview of the technology research objectives, payload description, design challenges and pre-flight testing results.

  20. Development of A Plant Navigation System

    International Nuclear Information System (INIS)

    Furuta, Tomihiko; Nakagawa, Tsuneo; Kubota, Ryuji; Ikeda, Kouji

    1998-01-01

    A 'Plant Navigation System (PNS)' is under development to assist nuclear power plant (NPP) operators by automatically displaying the plant situation and plant operational procedures on a CRT screen when abnormalities occur. The operation procedures given in a symptom-oriented manual are expressed in a tree - type flowchart (modified PAD). The optimum operation procedure for an NPP is selected automatically using built-in diagnostic logics based on the current status of the NPP. Concerning the plant situation, the PNS displays important information only on the current status of the NPP. A prototype PNS system is being constructed. (authors)

  1. 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.

  2. Radio transmission system for industrial area

    International Nuclear Information System (INIS)

    Iliescu, M.; Culcer, M.; Curuia, M.; Anghel, N.M.; Stefanescu, I.

    2003-01-01

    The paper deals with a data transmission system operating in a large, noisy industrial area. The radio transmission system permits data and commands communication between the local units of collecting data and a central monitoring and/or command station ( dispatch). The communication support are radio waves in the range 450 MHz. The transducers are of transmitter type, with 4-20 mA output signal, providing information about environmental and/or work parameters. Data are primarily acquisitioned in a data logger with microcontroller, then transmitted via a FSK radio modem and a radio station to the dispatch. Data logger can also be connected in a network. The dispatch personal computer receives and processes data and transmits commands. The system functioning is supervised by a communication software in MCS - 51 assembler and an application software in Visual C ++ . (author)

  3. A State-of-the-Art Survey of Indoor Positioning and Navigation Systems and Technologies

    Directory of Open Access Journals (Sweden)

    Wilson Sakpere

    2017-12-01

    Full Text Available The research and use of positioning and navigation technologies outdoors has seen a steady and exponential growth. Based on this success, there have been attempts to implement these technologies indoors, leading to numerous studies. Most of the algorithms, techniques and technologies used have been implemented outdoors. However, how they fare indoors is different altogether. Thus, several technologies have been proposed and implemented to improve positioning and navigation indoors. Among them are Infrared (IR, Ultrasound, Audible Sound, Magnetic, Optical and Vision, Radio Frequency (RF, Visible Light, Pedestrian Dead Reckoning (PDR/Inertial Navigation System (INS and Hybrid. The RF technologies include Bluetooth, Ultra-wideband (UWB, Wireless Sensor Network (WSN, Wireless Local Area Network (WLAN, Radio-Frequency Identification (RFID and Near Field Communication (NFC. In addition, positioning techniques applied in indoor positioning systems include the signal properties and positioning algorithms. The prevalent signal properties are Angle of Arrival (AOA, Time of Arrival (TOA, Time Difference of Arrival (TDOA and Received Signal Strength Indication (RSSI, while the positioning algorithms are Triangulation, Trilateration, Proximity and Scene Analysis/ Fingerprinting. This paper presents a state-of-the-art survey of indoor positioning and navigation systems and technologies, and their use in various scenarios. It analyses distinct positioning technology metrics such as accuracy, complexity, cost, privacy, scalability and usability. This paper has profound implications for future studies of positioning and navigation.

  4. The Creation of Differential Correction Systems and the Systems of Global Navigation Satellite System Monitoring

    National Research Council Canada - National Science Library

    Polishchuk, G. M; Kozlov, V. I; Urlichich, Y. M; Dvorkin, V. V; Gvozdev, V. V

    2002-01-01

    ... for the Russian Federation and a system of global navigation satellite system monitoring. These projects are some of the basic ones in the Federal program "Global Navigation System," aimed at maintenance and development of the GLONASS system...

  5. 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.

  6. Target relative navigation results from hardware-in-the-loop tests using the sinplex navigation system

    NARCIS (Netherlands)

    Steffes, S.; Dumke, M.; Heise, D.; Sagliano, M.; Samaan, M.; Theil, S.; Boslooper, E.C.; Oosterling, J.A.J.; Schulte, J.; Skaborn, D.; Söderholm, S.; Conticello, S.; Esposito, M.; Yanson, Y.; Monna, B.; Stelwagen, F.; Visee, R.

    2014-01-01

    The goal of the SINPLEX project is to develop an innovative solution to significantly reduce the mass of the navigation subsystem for exploration missions which include landing and/or rendezvous and capture phases. The system mass is reduced while still maintaining good navigation performance as

  7. Vision enhanced navigation for unmanned systems

    Science.gov (United States)

    Wampler, Brandon Loy

    A vision based simultaneous localization and mapping (SLAM) algorithm is evaluated for use on unmanned systems. SLAM is a technique used by a vehicle to build a map of an environment while concurrently keeping track of its location within the map, without a priori knowledge. The work in this thesis is focused on using SLAM as a navigation solution when global positioning system (GPS) service is degraded or temporarily unavailable. Previous work on unmanned systems that lead up to the determination that a better navigation solution than GPS alone is first presented. This previous work includes control of unmanned systems, simulation, and unmanned vehicle hardware testing. The proposed SLAM algorithm follows the work originally developed by Davidson et al. in which they dub their algorithm MonoSLAM [1--4]. A new approach using the Pyramidal Lucas-Kanade feature tracking algorithm from Intel's OpenCV (open computer vision) library is presented as a means of keeping correct landmark correspondences as the vehicle moves through the scene. Though this landmark tracking method is unusable for long term SLAM due to its inability to recognize revisited landmarks, as opposed to the Scale Invariant Feature Transform (SIFT) and Speeded Up Robust Features (SURF), its computational efficiency makes it a good candidate for short term navigation between GPS position updates. Additional sensor information is then considered by fusing INS and GPS information into the SLAM filter. The SLAM system, in its vision only and vision/IMU form, is tested on a table top, in an open room, and finally in an outdoor environment. For the outdoor environment, a form of the slam algorithm that fuses vision, IMU, and GPS information is tested. The proposed SLAM algorithm, and its several forms, are implemented in C++ using an Extended Kalman Filter (EKF). Experiments utilizing a live video feed from a webcam are performed. The different forms of the filter are compared and conclusions are made on

  8. 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)

  9. PulsarPlane: a feasibility study for millisecond radio pulsar navigation

    NARCIS (Netherlands)

    Buist, Peter; Hesselink, Henk; Gibbs, Alex; Keuning, Michel; Gaubitch, Nikolay; Noroozi, Arash; Bentum, Marinus Jan; Verhoeven, Chris; Heusdens, Richard; Fernandes, Jorge; Kabakchiev, Hristo; Kestilä, Antti

    2014-01-01

    Stars have been used -in what is called celestial navigation- since thousands of years by mankind. Celestial navigation was used extensively in aviation until the 1960s, and in marine navigation until recently. It has been investigated for agriculture applications, utilized for military aircraft

  10. Camera Based Navigation System with Augmented Reality

    Directory of Open Access Journals (Sweden)

    M. Marcu

    2012-06-01

    Full Text Available Nowadays smart mobile devices have enough processing power, memory, storage and always connected wireless communication bandwidth that makes them available for any type of application. Augmented reality (AR proposes a new type of applications that tries to enhance the real world by superimposing or combining virtual objects or computer generated information with it. In this paper we present a camera based navigation system with augmented reality integration. The proposed system aims to the following: the user points the camera of the smartphone towards a point of interest, like a building or any other place, and the application searches for relevant information about that specific place and superimposes the data over the video feed on the display. When the user moves the camera away, changing its orientation, the data changes as well, in real-time, with the proper information about the place that is now in the camera view.

  11. Systems and Methods for Determining Inertial Navigation System Faults

    Science.gov (United States)

    Bharadwaj, Raj Mohan (Inventor); Bageshwar, Vibhor L. (Inventor); Kim, Kyusung (Inventor)

    2017-01-01

    An inertial navigation system (INS) includes a primary inertial navigation system (INS) unit configured to receive accelerometer measurements from an accelerometer and angular velocity measurements from a gyroscope. The primary INS unit is further configured to receive global navigation satellite system (GNSS) signals from a GNSS sensor and to determine a first set of kinematic state vectors based on the accelerometer measurements, the angular velocity measurements, and the GNSS signals. The INS further includes a secondary INS unit configured to receive the accelerometer measurements and the angular velocity measurements and to determine a second set of kinematic state vectors of the vehicle based on the accelerometer measurements and the angular velocity measurements. A health management system is configured to compare the first set of kinematic state vectors and the second set of kinematic state vectors to determine faults associated with the accelerometer or the gyroscope based on the comparison.

  12. 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

  13. Orion Absolute Navigation System Progress and Challenges

    Science.gov (United States)

    Holt, Greg N.; D'Souza, Christopher

    2011-01-01

    The Orion spacecraft is being designed as NASA's next-generation exploration vehicle for crewed missions beyond Low-Earth Orbit. The navigation system for the Orion spacecraft is being designed in a Multi-Organizational Design Environment (MODE) team including contractor and NASA personnel. The system uses an Extended Kalman Filter to process measurements and determine the state. The design of the navigation system has undergone several iterations and modifications since its inception, and continues as a work-in-progress. This paper seeks to benchmark the current state of the design and some of the rationale and analysis behind it. There are specific challenges to address when preparing a timely and effective design for the Exploration Flight Test (EFT-1), while still looking ahead and providing software extensibility for future exploration missions. The primary measurements in a Near-Earth or Mid-Earth environment consist of GPS pseudorange and deltarange, but for future explorations missions the use of star-tracker and optical navigation sources need to be considered. Discussions are presented for state size and composition, processing techniques, and consider states. A presentation is given for the processing technique using the computationally stable and robust UDU formulation with an Agee-Turner Rank-One update. This allows for computational savings when dealing with many parameters which are modeled as slowly varying Gauss-Markov processes. Preliminary analysis shows up to a 50% reduction in computation versus a more traditional formulation. Several state elements are discussed and evaluated, including position, velocity, attitude, clock bias/drift, and GPS measurement biases in addition to bias, scale factor, misalignment, and non-orthogonalities of the accelerometers and gyroscopes. Another consideration is the initialization of the EKF in various scenarios. Scenarios such as single-event upset, ground command, pad alignment, cold start are discussed as are

  14. IMPELEMENTASI SISTEM PEMANTAUAN OBJEK BERGERAK DENGAN MEMANFAATKAN FREKUENSI RADIO MENGGUNAKAN GPS (GLOBAL POSITIONING SYSTEM)

    OpenAIRE

    Budi Triandi

    2010-01-01

    GPS was developed by the United States Department of Defense as a reliable means for accurate navigation. The system provides highly accurate position and velocity information and precise time on a continuous global basis to an unlimited number of properly equipped users. By using combined GPS receiver and microcontroller together with radio system, we can design a monitoring system for our vehicles and display the result on the computer. This system consists of a master module that transmits...

  15. Development of a new automotive navigation system; Shingata navigation system no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Sone, M; Nakano, H; Nakayama, O; Tanemura, E; Yoshitsugu, N; Watanabe, M [Nissan Motor Co. Ltd., Tokyo (Japan)

    1996-01-31

    An automotive navigation system was outlined. Features of this system are described below: map display called `Bird View` extending up to the horizon was commercialized; accuracy of determining the vehicle`s present position was realized using new algorithm; and automatic route selection was adopted. Human machine interface of this system also was completely reviewed. `Bird View` was realized by reading plane map data out from CD-ROM and converting them onto the coordinate on the virtual screen in front of the view point. Automatic selection which depends mostly on self-contained navigation adopts the certain way in comparison of the computation position in GPS. To assume vehicle advancing direction, employed were optical fiber gyroscope, geomagnetic sensor, and Karman filter making a good use of advantages of GPS, for the improvement of accuracy. For the automatic distance correction, a function of correcting pulse-distance conversion coefficient was employed, and the free maintenance was realized. 5 figs.

  16. Smart parking management and navigation system

    KAUST Repository

    Saadeldin, Mohamed

    2017-11-09

    Various examples are provided for smart parking management, which can include navigation. In one example, a system includes a base station controller configured to: receive a wireless signal from a parking controller located at a parking space; determine a received signal strength indicator (RSSI) from the wireless signal; and identify a presence of a vehicle located at the parking space based at least in part on the RSSI. In another example, a method includes receiving a wireless signals from a base station controller and a parking controller located at a parking space; determining RSSIs from the wireless signals; and determining a location of the mobile computing device in a parking facility based at least in part on the RSSIs. In another example, a RSSI can be received, a parking occupancy can be determined using the RSSI, and an electronic record can be updated based on the parking occupancy.

  17. 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.

  18. Energy-Aware Cognitive Radio Systems

    KAUST Repository

    Bedeer, Ebrahim

    2016-01-15

    The concept of energy-aware communications has spurred the interest of the research community in the most recent years due to various environmental and economical reasons. It becomes indispensable for wireless communication systems to shift their resource allocation problems from optimizing traditional metrics, such as throughput and latency, to an environmental-friendly energy metric. Although cognitive radio systems introduce spectrum efficient usage techniques, they employ new complex technologies for spectrum sensing and sharing that consume extra energy to compensate for overhead and feedback costs. Considering an adequate energy efficiency metric—that takes into account the transmit power consumption, circuitry power, and signaling overhead—is of momentous importance such that optimal resource allocations in cognitive radio systems reduce the energy consumption. A literature survey of recent energy-efficient based resource allocations schemes is presented for cognitive radio systems. The energy efficiency performances of these schemes are analyzed and evaluated under power budget, co-channel and adjacent-channel interferences, channel estimation errors, quality-of-service, and/or fairness constraints. Finally, the opportunities and challenges of energy-aware design for cognitive radio systems are discussed.

  19. Vibrotactile in-vehicle navigation system

    NARCIS (Netherlands)

    Erp, J.B.F. van; Veen, H.J. van

    2004-01-01

    A vibrotactile display, consisting ofeight vibrating elements or tactors mounted in a driver's seat, was tested in a driving simulator. Participants drove with visual, tactile and multimodal navigation displays through a built-up area. Workload and the reaction time to navigation messages were

  20. Mobile radio alternative systems study traffic model

    Science.gov (United States)

    Tucker, W. T.; Anderson, R. E.

    1983-06-01

    The markets for mobile radio services in non-urban areas of the United States are examined for the years 1985-2000. Three market categories are identified. New Services are defined as those for which there are different expressed ideas but which are not now met by any application of available technology. The complete fulfillment of the needs requires nationwide radio access to vehicles without knowledge of vehicle location, wideband data transmission from remote sites, one- and two way exchange of short data and control messages between vehicles and dispatch or control centers, and automatic vehicle location (surveillance). The commercial and public services market of interest to the study is drawn from existing users of mobile radio in non-urban areas who are dissatisfied with the geographical range or coverage of their systems. The mobile radio telephone market comprises potential users who require access to the public switched telephone network in areas that are not likely to be served by the traditional growth patterns of terrestrial mobile telephone services. Conservative, likely, and optimistic estimates of the markets are presented in terms of numbers of vehicles that will be served and the radio traffic they will generate.

  1. Error Analysis of Inertial Navigation Systems Using Test Algorithms

    OpenAIRE

    Vaispacher, Tomáš; Bréda, Róbert; Adamčík, František

    2015-01-01

    Content of this contribution is an issue of inertial sensors errors, specification of inertial measurement units and generating of test signals for Inertial Navigation System (INS). Given the different levels of navigation tasks, part of this contribution is comparison of the actual types of Inertial Measurement Units. Considering this comparison, there is proposed the way of solving inertial sensors errors and their modelling for low – cost inertial navigation applications. The last part is ...

  2. The impact of navigation systems on traffic safety

    NARCIS (Netherlands)

    Rooijen, T. van; Vonk, T.

    2007-01-01

    This paper studies the impact of navigation systems on traffic safety in the Netherlands. This study consists of four analyses: a literature survey, a database analysis, a user survey and an instrumented vehicle study. The results of the four sections show that navigation systems have a positive

  3. The impact of navigation systems on traffic safety

    NARCIS (Netherlands)

    Rooijen, T. van; Vonk, T.

    2008-01-01

    This paper studies the impact of navigation systems on traffic safety in the Netherlands. This study consists of four analyses: a literature survey, a database analysis, a user survey and an instrumented vehicle study. The results of the four sections show that navigation systems have a positive

  4. GNSS global navigation satellite systems : GPS, GLONASS, Galileo, and more

    CERN Document Server

    Hofmann-Wellenhof, Bernhard; Wasle, Elmar

    2008-01-01

    This book is an extension to the acclaimed scientific bestseller "GPS - Theory and Practice". It covers Global Navigation Satellite Systems (GNSS) and includes the Russian GLONASS, the European system Galileo, and additional systems.

  5. Design Issues for MEMS-Based Pedestrian Inertial Navigation Systems

    Directory of Open Access Journals (Sweden)

    P. S. Marinushkin

    2015-01-01

    Full Text Available The paper describes design issues for MEMS-based pedestrian inertial navigation systems. By now the algorithms to estimate navigation parameters for strap-down inertial navigation systems on the basis of plural observations have been already well developed. At the same time mathematical and software processing of information in the case of pedestrian inertial navigation systems has its specificity, due to the peculiarities of their functioning and exploitation. Therefore, there is an urgent task to enhance existing fusion algorithms for use in pedestrian navigation systems. For this purpose the article analyzes the characteristics of the hardware composition and configuration of existing systems of this class. The paper shows advantages of various technical solutions. Relying on their main features it justifies a choice of the navigation system architecture and hardware composition enabling improvement of the estimation accuracy of user position as compared to the systems using only inertial sensors. The next point concerns the development of algorithms for complex processing of heterogeneous information. To increase an accuracy of the free running pedestrian inertial navigation system we propose an adaptive algorithm for joint processing of heterogeneous information based on the fusion of inertial info rmation with magnetometer measurements using EKF approach. Modeling of the algorithm was carried out using a specially developed functional prototype of pedestrian inertial navigation system, implemented as a hardware/software complex in Matlab environment. The functional prototype tests of the developed system demonstrated an improvement of the navigation parameters estimation compared to the systems based on inertial sensors only. It enables to draw a conclusion that the synthesized algorithm provides satisfactory accuracy for calculating the trajectory of motion even when using low-grade inertial MEMS sensors. The developed algorithm can be

  6. 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.

  7. Evaluation of Mobile Phone Interference With Aircraft GPS Navigation Systems

    Science.gov (United States)

    Pace, Scott; Oria, A. J.; Guckian, Paul; Nguyen, Truong X.

    2004-01-01

    This report compiles and analyzes tests that were conducted to measure cell phone spurious emissions in the Global Positioning System (GPS) radio frequency band that could affect the navigation system of an aircraft. The cell phone in question had, as reported to the FAA (Federal Aviation Administration), caused interference to several GPS receivers on-board a small single engine aircraft despite being compliant with data filed at the time with the FCC by the manufacturer. NASA (National Aeronautics and Space Administration) and industry tests show that while there is an emission in the 1575 MHz GPS band due to a specific combination of amplifier output impedance and load impedance that induces instability in the power amplifier, these spurious emissions (i.e., not the intentional transmit signal) are similar to those measured on non-intentionally transmitting devices such as, for example, laptop computers. Additional testing on a wide sample of different commercial cell phones did not result in any emission in the 1575 MHz GPS Band above the noise floor of the measurement receiver.

  8. Comparative advantage between traditional and smart navigation systems

    Science.gov (United States)

    Shin, Jeongkyu; Kim, Pan-Jun; Kim, Seunghwan

    2013-03-01

    The smart navigation system that refers to real-time traffic data is believed to be superior to traditional navigation systems. To verify this belief, we created an agent-based traffic model and examined the effect of changing market share of the traditional shortest-travel-time algorithm based navigation and the smart navigation system. We tested our model on the grid and actual metropolitan road network structures. The result reveals that the traditional navigation system have better performance than the smart one as the market share of the smart navigation system exceeds a critical value, which is contrary to conventional expectation. We suggest that the superiority inversion between agent groups is strongly related to the traffic weight function form, and is general. We also found that the relationship of market share, traffic flow density and travel time is determined by the combination of congestion avoidance behavior of the smartly navigated agents and the inefficiency of shortest-travel-time based navigated agents. Our results can be interpreted with the minority game and extended to the diverse topics of opinion dynamics. This work was supported by the Original Technology Research Program for Brain Science through the National Research Foundation of Korea funded by the Ministry of Education, Science and Technology(No. 2010-0018847).

  9. Information content in reflected global navigation satellite system signals

    DEFF Research Database (Denmark)

    Høeg, Per; Carlstrom, Anders

    2011-01-01

    The direct signals from satellites in global satellite navigation satellites systems (GNSS) as, GPS, GLONASS and GALILEO, constitute the primary source for positioning, navigation and timing from space. But also the reflected GNSS signals contain an important information content of signal travel...

  10. WAYS OF NAVIGATION SYSTEMS DEVELOPMENT WITHIN THE IMPLEMENTATION OF THE CNS/ATM CONCEPT

    Directory of Open Access Journals (Sweden)

    Igor A. Chekhov

    2017-01-01

    Full Text Available The general development principles of the civil aviation air navigation systems for the next years according to the concept of International Civil Aviation Organization (IСAO CNS/ATM are stated in the article. It was reflected in the Global air navigation plan of IСAO accepted in 2013. The author considered the structure of block modernization of aviation system directed to optimization according to four main characteristics, such as: operations at the airports; systems and data interoperable on a global scale; optimum capacity and flexible flight routes, and also effective trajectories of flight. At the same time the main attention in the plan is paid to questions of the performance based navigation (PBN, the basic theses of which lean on four main units that make the concept of PBN. The possible ways of the specified blocks implementation taking into account features of the Russian Federation airspace use are considered in this paper. On the basis of the carried-out analysis conclusions are drawn on gradual transition from the RNAV navigation specifications to the RNP specifications, on increase in accuracy of navigation by modernization of ground radio navigational aids, both on a flight route and airspace of airfield area, on need of continuing the development of inexact calling schemes, using GNSS, with the subsequent transition to schemes of exact landing approaches by means of functional additions to GLONASS – GBAS and SBAS, also on the need of opportunities research in the domestic system SBAS (SDKM for the increase in accuracy of navigation at various stages of flight. At the same time, standard instrument routes of arrival and departure (SID/STAR have to be carried out in the mode of constant climb or continuous descent.

  11. 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...

  12. Real-Time Measurements for Adaptive and Cognitive Radio Systems

    Directory of Open Access Journals (Sweden)

    Hüseyin Arslan

    2009-01-01

    Full Text Available Adaptive and cognitive radios (CR have been becoming popular for optimizing mobile radio system transmission and reception. One of the most important elements of the adaptive radio and CR concepts is the ability to measure, sense, learn about, and be aware of parameters related to the radio channel characteristics, availability of spectrum and power, interference and noise temperature, operational environment of radio, user requirements and applications, available networks and infrastructures, local policies, other operating restrictions, and so on. This paper discusses some of the important measurement parameters for enabling adaptive radio and CR systems along with their relationships and impacts on the performance including relevant challenges.

  13. JPL Space Telecommunications Radio System Operating Environment

    Science.gov (United States)

    Lux, James P.; Lang, Minh; Peters, Kenneth J.; Taylor, Gregory H.; Duncan, Courtney B.; Orozco, David S.; Stern, Ryan A.; Ahten, Earl R.; Girard, Mike

    2013-01-01

    A flight-qualified implementation of a Software Defined Radio (SDR) Operating Environment for the JPL-SDR built for the CoNNeCT Project has been developed. It is compliant with the NASA Space Telecommunications Radio System (STRS) Architecture Standard, and provides the software infrastructure for STRS compliant waveform applications. This software provides a standards-compliant abstracted view of the JPL-SDR hardware platform. It uses industry standard POSIX interfaces for most functions, as well as exposing the STRS API (Application Programming In terface) required by the standard. This software includes a standardized interface for IP components instantiated within a Xilinx FPGA (Field Programmable Gate Array). The software provides a standardized abstracted interface to platform resources such as data converters, file system, etc., which can be used by STRS standards conformant waveform applications. It provides a generic SDR operating environment with a much smaller resource footprint than similar products such as SCA (Software Communications Architecture) compliant implementations, or the DoD Joint Tactical Radio Systems (JTRS).

  14. Mobile Robot Designed with Autonomous Navigation System

    Science.gov (United States)

    An, Feng; Chen, Qiang; Zha, Yanfang; Tao, Wenyin

    2017-10-01

    With the rapid development of robot technology, robots appear more and more in all aspects of life and social production, people also ask more requirements for the robot, one is that robot capable of autonomous navigation, can recognize the road. Take the common household sweeping robot as an example, which could avoid obstacles, clean the ground and automatically find the charging place; Another example is AGV tracking car, which can following the route and reach the destination successfully. This paper introduces a new type of robot navigation scheme: SLAM, which can build the environment map in a totally strange environment, and at the same time, locate its own position, so as to achieve autonomous navigation function.

  15. 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

  16. METHODOLOGY FOR ANALYSIS OF DECISION MAKING IN AIR NAVIGATION SYSTEM

    Directory of Open Access Journals (Sweden)

    Volodymyr Kharchenko

    2011-03-01

    Full Text Available Abstract. In the research of Air Navigation System as a complex socio-technical system the methodologyof analysis of human-operator's decision-making has been developed. The significance of individualpsychologicalfactors as well as the impact of socio-psychological factors on the professional activities of ahuman-operator during the flight situation development from normal to catastrophic were analyzed. On thebasis of the reflexive theory of bipolar choice the expected risks of decision-making by the Air NavigationSystem's operator influenced by external environment, previous experience and intentions were identified.The methods for analysis of decision-making by the human-operator of Air Navigation System usingstochastic networks have been developed.Keywords: Air Navigation System, bipolar choice, human operator, decision-making, expected risk, individualpsychologicalfactors, methodology of analysis, reflexive model, socio-psychological factors, stochastic network.

  17. Goldstone-Apple Valley Radio Telescope System Theory of Operation

    Science.gov (United States)

    Stephan, George R.

    1997-01-01

    The purpose of this learning module is to enable learners to describe how the Goldstone-Apple Valley Radio Telescope (GAVRT) system functions in support of Apple Valley Science and Technology Center's (AVSTC) client schools' radio astronomy activities.

  18. A navigational evaluation model for content management systems

    International Nuclear Information System (INIS)

    Gilani, S.; Majeed, A.

    2016-01-01

    Web applications are widely used world-wide, however it is important that the navigation of these websites is effective, to enhance usability. Navigation is not limited to links between pages, it is also how we complete a task. Navigational structure presented as hypertext is one of the most important component of the Web application besides content and presentation. The main objective of this paper is to explore the navigational structure of various open source Content Management Systems from the developer's perspective. For this purpose three CMS are chosen which are WordPress, Joomla, and Drupal. Objective of the research is to identify the important navigational aspects present in these CMSs. Moreover, a comparative study of these CMSs in terms of navigational support is required. For this purpose an industrial survey is conducted based on our proposed navigational evaluation model. The results shows that there exist correlation between the identified factors and these CMSs provide helpful and effective navigational support to their users. (author)

  19. Engineering satellite-based navigation and timing global navigation satellite systems, signals, and receivers

    CERN Document Server

    Betz, J

    2016-01-01

    This book describes the design and performance analysis of satnav systems, signals, and receivers. It also provides succinct descriptions and comparisons of all the world’s satnav systems. Its comprehensive and logical structure addresses all satnav signals and systems in operation and being developed. Engineering Satellite-Based Navigation and Timing: Global Navigation Satellite Systems, Signals, and Receivers provides the technical foundation for designing and analyzing satnav signals, systems, and receivers. Its contents and structure address all satnav systems and signals: legacy, modernized, and new. It combines qualitative information with detailed techniques and analyses, providing a comprehensive set of insights and engineering tools for this complex multidisciplinary field. Part I describes system and signal engineering including orbital mechanics and constellation design, signal design principles and underlying considerations, link budgets, qua tifying receiver performance in interference, and e...

  20. Navigation Operations with Prototype Components of an Automated Real-Time Spacecraft Navigation System

    Science.gov (United States)

    Cangahuala, L.; Drain, T. R.

    1999-01-01

    At present, ground navigation support for interplanetary spacecraft requires human intervention for data pre-processing, filtering, and post-processing activities; these actions must be repeated each time a new batch of data is collected by the ground data system.

  1. Radio Frequency Microelectromechanical Systems [Book Chapter Manuscript

    Energy Technology Data Exchange (ETDEWEB)

    Nordquist, Christopher [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Olsson, Roy H. [Defense Advanced Research Projects Agency (DARPA), Albuquerque, NM (United States)

    2014-12-15

    Radio frequency microelectromechanical system (RF MEMS) devices are microscale devices that achieve superior performance relative to other technologies by taking advantage of the accuracy, precision, materials, and miniaturization available through microfabrication. To do this, these devices use their mechanical and electrical properties to perform a specific RF electrical function such as switching, transmission, or filtering. RF MEMS has been a popular area of research since the early 1990s, and within the last several years, the technology has matured sufficiently for commercialization and use in commercial market systems.

  2. 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

  3. IMPLEMENTATION OF INTERTIAL NAVIGATION SYSTEM MODEL DURING AIRCRAFT TESTING

    Directory of Open Access Journals (Sweden)

    2016-01-01

    Full Text Available The flight subset control is required during the aviation equipment test flights. In order to achieve this objective the complex consisting of strap down inertial navigation system (SINS and user equipment of satellite navigation systems (SNS can be used. Such combination needs to be used for error correction in positioning which is accumulated in SINS with time. This article shows the research results of the inertial navigation system (INS model. The results of the position- ing error calculation for various INS classes are given. Each of the examined INS has a different accumulated error for the same time lag. The methods of combining information of INS and SRNS are covered. The results obtained can be applied for upgrading the aircraft flight and navigation complexes. In particular, they can allow to continuously determine speed, coordinates, angular situation and repositioning rate of change of axes of the instrument frame.

  4. Beamsteerable GNSS Radio Occultation ASIC

    Data.gov (United States)

    National Aeronautics and Space Administration — We will develop an integrated RF ASIC to enable high quality radio occultation (RO) weather observations using the Global Navigations System Satellite (GNSS)...

  5. THE DEVELOPMENT OF NAVIGATION SYSTEMS IN CIVIL AVIATION

    Directory of Open Access Journals (Sweden)

    Anastasiya Sergeyevna Stepanenko

    2017-01-01

    Full Text Available The article describes the history of navigation systems formation, such as "Cicada" system, which at that time could compete with the US "Transit", European, Chinese Beidou navigation system and the Japanese Quasi-Zenit.The detailed information about improving the American GPS system, launched in 1978 and working till now is provided. The characteristics of GPS-III counterpart "Transit", which became the platform for creating such modern globalnavigation systems as GLONASS and GPS. The process of implementation of the GLONASS system in civil aviation, itssegments, functions and features are considered. The stages of GLONASS satellite system orbital grouping formation are analyzed. The author draws the analogy with the American GPS system, the GALILEO system, which has a number of additional advantages, are given. The author remarks the features of the European counterpart of the GALILEO global nav- igation system. One of the goals of this system is to provide a high-precision positioning system, which Europe can rely on regardless of the Russian GLONASS system, the US - GPS and the Chinese Beidou. GALILEO offers a unique global search and rescue function called SAR, with an important feedback function. The peculiarities of Chinese scientists’ navi- gation system, the Beidou satellite system, and the Japanese global Quasi-Zenith Satellite System are described.Global navigation systems development tendencies are considered. The author dwells upon the path to world satel- lite systems globalization, a good example of which is the trend towards GLONASS and Beidou unification. Most attention was paid to the latest development of Russian scientists’ autonomous navigation system SINS 2015, which is a strap-down inertial navigation system and allows you to navigate the aircraft without being connected to a global satellite system. The ways of navigation systems further development in Russia are determined. The two naturally opposite directions are

  6. Using the SLAC VHF and UHF radio systems

    International Nuclear Information System (INIS)

    Struven, W.

    1987-02-01

    The use of the SLAC VHF and UHF Radio Systems and the Tunnel Antenna Systems as they are presently configured is described. The original radio system was built in 1966 and has grown in scope over the years. The Tunnel Antenna Systems were developed for, and first installed in, the PEP ring, and later added to other tunnels and redesigned to cover the UHF range, as well as VHF. The UHF radio system was designed and built for SLC use, and was first used in the SLC Arcs. The three radio systems will be described and the capabilities of each system will be defined

  7. Space Telecommunications Radio System (STRS) Compliance Testing

    Science.gov (United States)

    Handler, Louis M.

    2011-01-01

    The Space Telecommunications Radio System (STRS) defines an open architecture for software defined radios. This document describes the testing methodology to aid in determining the degree of compliance to the STRS architecture. Non-compliances are reported to the software and hardware developers as well as the NASA project manager so that any non-compliances may be fixed or waivers issued. Since the software developers may be divided into those that provide the operating environment including the operating system and STRS infrastructure (OE) and those that supply the waveform applications, the tests are divided accordingly. The static tests are also divided by the availability of an automated tool that determines whether the source code and configuration files contain the appropriate items. Thus, there are six separate step-by-step test procedures described as well as the corresponding requirements that they test. The six types of STRS compliance tests are: STRS application automated testing, STRS infrastructure automated testing, STRS infrastructure testing by compiling WFCCN with the infrastructure, STRS configuration file testing, STRS application manual code testing, and STRS infrastructure manual code testing. Examples of the input and output of the scripts are shown in the appendices as well as more specific information about what to configure and test in WFCCN for non-compliance. In addition, each STRS requirement is listed and the type of testing briefly described. Attached is also a set of guidelines on what to look for in addition to the requirements to aid in the document review process.

  8. Contribution Towards Practical Cognitive Radios Systems

    KAUST Repository

    Ben Ghorbel, Mahdi

    2013-07-01

    Cognitive radios is one of the hot topics for emerging and future wireless commu- nication. It has been proposed as a suitable solution for the spectrum scarcity caused by the increase in frequency demand. The concept is based on allowing unlicensed users, called cognitive or secondary users, to share the unoccupied frequency bands with their owners, called the primary users, under constraints on the interference they cause to them. The objective of our work is to propose some enhancements to cognitive radio systems while taking into account practical constraints. Cogni- tive radios requires a capability to detect spectrum holes (spectrum sensing) and a scheduling flexibility to avoid the occupied spectrum and selectively use the empty spectrum (dynamic resource allocation). Thus, the work is composed of two main parts. The first part focuses on cooperative spectrum sensing. We compute in this part the analytical performance of cooperative spectrum sensing under non identical and imperfect channels. Different schemes are considered for the cooperation between users such as hard binary, censored information, quantized, and soft information. The second part focuses on the dynamic resource allocation. We first propose low-cost re- source allocation algorithms that use location information to estimate the interference to primary users to replace absence of instantaneous channel state information. We extend these algorithms to handle practical implementation constraints such as dis- 5 crete bit-loading and collocated subcarriers allocations. We then propose a reduced dimension approach based on the grouping of subcarriers into clusters and performing the resource allocation over clusters of subcarriers instead of single subcarriers. This approach is shown to reduce the computational complexity of the algorithm with lim- ited performance loss. In addition, it is valid for a generic set of resource allocation problems in presence of co-channel interference between users.

  9. 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.

  10. Implementation of a vector-based tracking loop receiver in a pseudolite navigation system.

    Science.gov (United States)

    So, Hyoungmin; Lee, Taikjin; Jeon, Sanghoon; Kim, Chongwon; Kee, Changdon; Kim, Taehee; Lee, Sanguk

    2010-01-01

    We propose a vector tracking loop (VTL) algorithm for an asynchronous pseudolite navigation system. It was implemented in a software receiver and experiments in an indoor navigation system were conducted. Test results show that the VTL successfully tracks signals against the near-far problem, one of the major limitations in pseudolite navigation systems, and could improve positioning availability by extending pseudolite navigation coverage.

  11. Novel measurement-based indoor cellular radio system design

    OpenAIRE

    Aragón-Zavala, A

    2008-01-01

    A scaleable, measurement-based radio methodology has been created to use for the design, planing and optimisation of in door cellular radio systems. The development of this measurement-based methodology was performed having in mind that measurements are of ten required to valiate radio coverage in a building. Therefore, the concept of using care fully calibrated measurements to design and optimise a system is feasible since these measurements can easily be obtained prior to system deployment ...

  12. A UHF RFID positioning system for use in warehouse navigation by employees with cognitive disability.

    Science.gov (United States)

    Gunther, Eric J M; Sliker, Levin J; Bodine, Cathy

    2017-11-01

    Unemployment among the almost 5 million working-age adults with cognitive disabilities in the USA is a costly problem in both tax dollars and quality of life. Job coaching is an effective tool to overcome this, but the cost of job coaching services sums with every new employee or change of employment roles. There is a need for a cost-effective, automated alternative to job coaching that incurs a one-time cost and can be reused for multiple employees or roles. An effective automated job coach must be aware of its location and the location of destinations within the job site. This project presents a design and prototype of a cart-mounted indoor positioning and navigation system with necessary original software using Ultra High Frequency Radio Frequency Identification (UHF RFID). The system presented in this project for use within a warehouse setting is one component of an automated job coach to assist in the job of order filler. The system demonstrated accuracy to within 0.3 m under the correct conditions with strong potential to serve as the basis for an effective indoor navigation system to assist warehouse workers with disabilities. Implications for rehabilitation An automated job coach could improve employability of and job retention for people with cognitive disabilities. An indoor navigation system using ultra high frequency radio frequency identification was proposed with an average positioning accuracy of 0.3 m. The proposed system, in combination with a non-linear context-aware prompting system, could be used as an automated job coach for warehouse order fillers with cognitive disabilities.

  13. Distributed Ship Navigation Control System Based on Dual Network

    Science.gov (United States)

    Yao, Ying; Lv, Wu

    2017-10-01

    Navigation system is very important for ship’s normal running. There are a lot of devices and sensors in the navigation system to guarantee ship’s regular work. In the past, these devices and sensors were usually connected via CAN bus for high performance and reliability. However, as the development of related devices and sensors, the navigation system also needs the ability of high information throughput and remote data sharing. To meet these new requirements, we propose the communication method based on dual network which contains CAN bus and industrial Ethernet. Also, we import multiple distributed control terminals with cooperative strategy based on the idea of synchronizing the status by multicasting UDP message contained operation timestamp to make the system more efficient and reliable.

  14. 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.

  15. Orion Absolute Navigation System Progress and Challenge

    Science.gov (United States)

    Holt, Greg N.; D'Souza, Christopher

    2012-01-01

    The absolute navigation design of NASA's Orion vehicle is described. It has undergone several iterations and modifications since its inception, and continues as a work-in-progress. This paper seeks to benchmark the current state of the design and some of the rationale and analysis behind it. There are specific challenges to address when preparing a timely and effective design for the Exploration Flight Test (EFT-1), while still looking ahead and providing software extensibility for future exploration missions. The primary onboard measurements in a Near-Earth or Mid-Earth environment consist of GPS pseudo-range and delta-range, but for future explorations missions the use of star-tracker and optical navigation sources need to be considered. Discussions are presented for state size and composition, processing techniques, and consider states. A presentation is given for the processing technique using the computationally stable and robust UDU formulation with an Agee-Turner Rank-One update. This allows for computational savings when dealing with many parameters which are modeled as slowly varying Gauss-Markov processes. Preliminary analysis shows up to a 50% reduction in computation versus a more traditional formulation. Several state elements are discussed and evaluated, including position, velocity, attitude, clock bias/drift, and GPS measurement biases in addition to bias, scale factor, misalignment, and non-orthogonalities of the accelerometers and gyroscopes. Another consideration is the initialization of the EKF in various scenarios. Scenarios such as single-event upset, ground command, and cold start are discussed as are strategies for whole and partial state updates as well as covariance considerations. Strategies are given for dealing with latent measurements and high-rate propagation using multi-rate architecture. The details of the rate groups and the data ow between the elements is discussed and evaluated.

  16. An Indoor Navigation System for the Visually Impaired

    Directory of Open Access Journals (Sweden)

    Luis A. Guerrero

    2012-06-01

    Full Text Available Navigation in indoor environments is highly challenging for the severely visually impaired, particularly in spaces visited for the first time. Several solutions have been proposed to deal with this challenge. Although some of them have shown to be useful in real scenarios, they involve an important deployment effort or use artifacts that are not natural for blind users. This paper presents an indoor navigation system that was designed taking into consideration usability as the quality requirement to be maximized. This solution enables one to identify the position of a person and calculates the velocity and direction of his movements. Using this information, the system determines the user’s trajectory, locates possible obstacles in that route, and offers navigation information to the user. The solution has been evaluated using two experimental scenarios. Although the results are still not enough to provide strong conclusions, they indicate that the system is suitable to guide visually impaired people through an unknown built environment.

  17. An indoor navigation system for the visually impaired.

    Science.gov (United States)

    Guerrero, Luis A; Vasquez, Francisco; Ochoa, Sergio F

    2012-01-01

    Navigation in indoor environments is highly challenging for the severely visually impaired, particularly in spaces visited for the first time. Several solutions have been proposed to deal with this challenge. Although some of them have shown to be useful in real scenarios, they involve an important deployment effort or use artifacts that are not natural for blind users. This paper presents an indoor navigation system that was designed taking into consideration usability as the quality requirement to be maximized. This solution enables one to identify the position of a person and calculates the velocity and direction of his movements. Using this information, the system determines the user's trajectory, locates possible obstacles in that route, and offers navigation information to the user. The solution has been evaluated using two experimental scenarios. Although the results are still not enough to provide strong conclusions, they indicate that the system is suitable to guide visually impaired people through an unknown built environment.

  18. A full 3D-navigation system in a suitcase.

    Science.gov (United States)

    Freysinger, W; Truppe, M J; Gunkel, A R; Thumfart, W F

    2001-01-01

    To reduce the impact of contemporary 3D-navigation systems on the environment of typical otorhinolaryngologic operating rooms, we demonstrate that a transfer of navigation software to modern high-power notebook computers is feasible and results in a practicable way to provide positional information to a surgeon intraoperatively. The ARTMA Virtual Patient System has been implemented on a Macintosh PowerBook G3 and, in connection with the Polhemus FASTRAK digitizer, provides intraoperative positional information during endoscopic endonasal surgery. Satisfactory intraoperative navigation has been realized in two- and three-dimensional medical image data sets (i.e., X-ray, ultrasound images, CT, and MR) and live video. This proof-of-concept study demonstrates that acceptable ergonomics and excellent performance of the system can be achieved with contemporary high-end notebook computers. Copyright 2001 Wiley-Liss, Inc.

  19. Oral and maxillofacial surgery with computer-assisted navigation system.

    Science.gov (United States)

    Kawachi, Homare; Kawachi, Yasuyuki; Ikeda, Chihaya; Takagi, Ryo; Katakura, Akira; Shibahara, Takahiko

    2010-01-01

    Intraoperative computer-assisted navigation has gained acceptance in maxillofacial surgery with applications in an increasing number of indications. We adapted a commercially available wireless passive marker system which allows calibration and tracking of virtually every instrument in maxillofacial surgery. Virtual computer-generated anatomical structures are displayed intraoperatively in a semi-immersive head-up display. Continuous observation of the operating field facilitated by computer assistance enables surgical navigation in accordance with the physician's preoperative plans. This case report documents the potential for augmented visualization concepts in surgical resection of tumors in the oral and maxillofacial region. We report a case of T3N2bM0 carcinoma of the maxillary gingival which was surgically resected with the assistance of the Stryker Navigation Cart System. This system was found to be useful in assisting preoperative planning and intraoperative monitoring.

  20. HyMoTrack: A Mobile AR Navigation System for Complex Indoor Environments.

    Science.gov (United States)

    Gerstweiler, Georg; Vonach, Emanuel; Kaufmann, Hannes

    2015-12-24

    Navigating in unknown big indoor environments with static 2D maps is a challenge, especially when time is a critical factor. In order to provide a mobile assistant, capable of supporting people while navigating in indoor locations, an accurate and reliable localization system is required in almost every corner of the building. We present a solution to this problem through a hybrid tracking system specifically designed for complex indoor spaces, which runs on mobile devices like smartphones or tablets. The developed algorithm only uses the available sensors built into standard mobile devices, especially the inertial sensors and the RGB camera. The combination of multiple optical tracking technologies, such as 2D natural features and features of more complex three-dimensional structures guarantees the robustness of the system. All processing is done locally and no network connection is needed. State-of-the-art indoor tracking approaches use mainly radio-frequency signals like Wi-Fi or Bluetooth for localizing a user. In contrast to these approaches, the main advantage of the developed system is the capability of delivering a continuous 3D position and orientation of the mobile device with centimeter accuracy. This makes it usable for localization and 3D augmentation purposes, e.g. navigation tasks or location-based information visualization.

  1. HyMoTrack: A Mobile AR Navigation System for Complex Indoor Environments

    Directory of Open Access Journals (Sweden)

    Georg Gerstweiler

    2015-12-01

    Full Text Available Navigating in unknown big indoor environments with static 2D maps is a challenge, especially when time is a critical factor. In order to provide a mobile assistant, capable of supporting people while navigating in indoor locations, an accurate and reliable localization system is required in almost every corner of the building. We present a solution to this problem through a hybrid tracking system specifically designed for complex indoor spaces, which runs on mobile devices like smartphones or tablets. The developed algorithm only uses the available sensors built into standard mobile devices, especially the inertial sensors and the RGB camera. The combination of multiple optical tracking technologies, such as 2D natural features and features of more complex three-dimensional structures guarantees the robustness of the system. All processing is done locally and no network connection is needed. State-of-the-art indoor tracking approaches use mainly radio-frequency signals like Wi-Fi or Bluetooth for localizing a user. In contrast to these approaches, the main advantage of the developed system is the capability of delivering a continuous 3D position and orientation of the mobile device with centimeter accuracy. This makes it usable for localization and 3D augmentation purposes, e.g. navigation tasks or location-based information visualization.

  2. A System for Fast Navigation of Autonomous Vehicles

    Science.gov (United States)

    1991-09-01

    AD-A243 523 4, jj A System for Fast Navigation of Autonomous Vehicles Sanjiv Singh, Dai Feng, Paul Keller, Gary Shaffer, Wen Fan Shi, Dong Hun Shin...FUNDING NUMBERS A System for Fast Navigation of Autonomous Vehicles 6. AUTHOR(S) S. Singh, D. Feng, P. Keller, G. Shaffer, W.F. Shi, D.H. Shin, J. West...common in the control of autonomous vehicles to establish the necessary kinematic models but to ignore an explicit representation of the vehicle dynamics

  3. Ground-Based Global Navigation Satellite System GLONASS (GLObal NAvigation Satellite System) Combined Broadcast Ephemeris Data (daily files) from NASA CDDIS

    Data.gov (United States)

    National Aeronautics and Space Administration — This dataset consists of ground-based Global Navigation Satellite System (GNSS) GLONASS Combined Broadcast Ephemeris Data (daily files of all distinct navigation...

  4. Advanced Navigation Aids System based on Augmented Reality

    Directory of Open Access Journals (Sweden)

    Jaeyong OH

    2016-12-01

    Full Text Available Many maritime accidents have been caused by human-error including such things as inadequate watch keeping and/or mistakes in ship handling. Also, new navigational equipment has been developed using Information Technology (IT technology to provide various kinds of information for safe navigation. Despite these efforts, the reduction of maritime accidents has not occurred to the degree expected because, navigational equipment provides too much information, and this information is not well organized, such that users feel it to be complicated rather than helpful. In this point of view, the method of representation of navigational information is more important than the quantity of that information and research is required on the representation of information to make that information more easily understood and to allow decisions to be made correctly and promptly. In this paper, we adopt Augmented Reality (AR technologies for the representation of information. AR is a 3D computer graphics technology that blends virtual reality and the real world. Recently, this technology has been widely applied in our daily lives because it can provide information more effectively to users. Therefore, we propose a new concept, a navigational system based on AR technology; we review experimental results from a ship-handling simulator and from an open sea test to verify the efficiency of the proposed system.

  5. A Practical Route Search System for Amusement Parks Navigation

    Directory of Open Access Journals (Sweden)

    Takahiro Shibuya

    2013-12-01

    Full Text Available It is very difficult to find the minimum route to travel in amusement park navigation. A searching system for visitors would be useful. Therefore, we constructed a system to find the route with the minimum total traveling time. Facility visitors can employ this system on a smart phone. The system is composed of Java and a Java Servlet. We conclude that our system is useful and can greatly shorten travel time within a typical amusement park.

  6. Future Standardization of Space Telecommunications Radio System with Core Flight System

    Science.gov (United States)

    Briones, Janette C.; Hickey, Joseph P.; Roche, Rigoberto; Handler, Louis M.; Hall, Charles S.

    2016-01-01

    NASA Glenn Research Center (GRC) is integrating the NASA Space Telecommunications Radio System (STRS) Standard with the Core Flight System (cFS), an avionics software operating environment. The STRS standard provides a common, consistent framework to develop, qualify, operate and maintain complex, reconfigurable and reprogrammable radio systems. The cFS is a flexible, open architecture that features a plugand- play software executive called the Core Flight Executive (cFE), a reusable library of software components for flight and space missions and an integrated tool suite. Together, STRS and cFS create a development environment that allows for STRS compliant applications to reference the STRS application programmer interfaces (APIs) that use the cFS infrastructure. These APIs are used to standardize the communication protocols on NASAs space SDRs. The cFS-STRS Operating Environment (OE) is a portable cFS library, which adds the ability to run STRS applications on existing cFS platforms. The purpose of this paper is to discuss the cFS-STRS OE prototype, preliminary experimental results performed using the Advanced Space Radio Platform (ASRP), the GRC S- band Ground Station and the SCaN (Space Communication and Navigation) Testbed currently flying onboard the International Space Station (ISS). Additionally, this paper presents a demonstration of the Consultative Committee for Space Data Systems (CCSDS) Spacecraft Onboard Interface Services (SOIS) using electronic data sheets (EDS) inside cFE. This configuration allows for the data sheets to specify binary formats for data exchange between STRS applications. The integration of STRS with cFS leverages mission-proven platform functions and mitigates barriers to integration with future missions. This reduces flight software development time and the costs of software-defined radio (SDR) platforms. Furthermore, the combined benefits of STRS standardization with the flexibility of cFS provide an effective, reliable and

  7. Data Analysis Techniques for a Lunar Surface Navigation System Testbed

    Science.gov (United States)

    Chelmins, David; Sands, O. Scott; Swank, Aaron

    2011-01-01

    NASA is interested in finding new methods of surface navigation to allow astronauts to navigate on the lunar surface. In support of the Vision for Space Exploration, the NASA Glenn Research Center developed the Lunar Extra-Vehicular Activity Crewmember Location Determination System and performed testing at the Desert Research and Technology Studies event in 2009. A significant amount of sensor data was recorded during nine tests performed with six test subjects. This paper provides the procedure, formulas, and techniques for data analysis, as well as commentary on applications.

  8. Research notes : solar powered navigational lighting system demonstration project.

    Science.gov (United States)

    2011-04-01

    ODOT will be installing a solar powered navigational lighting system on the AstoriaMegler Bridge as part of a pilot project approved by the Federal Highways Administration (FHWA). The coastal bridge is the connection across the Columbia River on U.S....

  9. 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.

  10. Organizations And Services In The System Of International Aviation Navigation

    Directory of Open Access Journals (Sweden)

    Alexander I. Travnikov

    2015-03-01

    Full Text Available In the present article author reveals the order of creation, structure, aims and objectives of national and international intergovernmental aeronautical organizations, governing procedure for flight operations and providing direct air traffic control over sovereign territory and abroad. In this article, author notes that in the world there are three main organizational and legal forms of air traffic control systems to ensure coordination between civil and military air navigation services (agencies. In the Russian Federation, author notes that air navigation services on behalf of the State are made by the State Corporation for Air Traffic Management that has the legal status of the commercial organization - the Federal State Unitary Enterprise. Author analyzes the work of the Organization for the Civil Air Navigation Services (CANSO, the International Federation of Air Traffic Controllers (IFATCA. During the study author also concludes that in the past decade, there is the steady trend of transferring functions of air navigation from the State to commercial organizations (joint stock companies and limited liability companies, which are financed from the funds received as payment for air traffic services. The responsibility for the improper maintenance of international air navigation, of course, is borne by the State. Author notes that regional and international intergovernmental aeronautical organizations operate in respect of all aircraft (public, civil, experimental, i.e., perform general air navigation, unlike ICAO, which takes standards and recommended practices, rules and procedures for safety and air traffic services only to civil aircraft, that does not ensure the creation of a regulatory framework for the global unification of aeronautical processes.

  11. Information Management: Military Affiliate Radio System (MARS)

    National Research Council Canada - National Science Library

    1986-01-01

    .... It describes a program sponsored by the Department of Defense and supported by the Department of the Army in which military installations, military units, clubs, and volunteer licensed amateur radio...

  12. An alternative ionospheric correction model for global navigation satellite systems

    Science.gov (United States)

    Hoque, M. M.; Jakowski, N.

    2015-04-01

    The ionosphere is recognized as a major error source for single-frequency operations of global navigation satellite systems (GNSS). To enhance single-frequency operations the global positioning system (GPS) uses an ionospheric correction algorithm (ICA) driven by 8 coefficients broadcasted in the navigation message every 24 h. Similarly, the global navigation satellite system Galileo uses the electron density NeQuick model for ionospheric correction. The Galileo satellite vehicles (SVs) transmit 3 ionospheric correction coefficients as driver parameters of the NeQuick model. In the present work, we propose an alternative ionospheric correction algorithm called Neustrelitz TEC broadcast model NTCM-BC that is also applicable for global satellite navigation systems. Like the GPS ICA or Galileo NeQuick, the NTCM-BC can be optimized on a daily basis by utilizing GNSS data obtained at the previous day at monitor stations. To drive the NTCM-BC, 9 ionospheric correction coefficients need to be uploaded to the SVs for broadcasting in the navigation message. Our investigation using GPS data of about 200 worldwide ground stations shows that the 24-h-ahead prediction performance of the NTCM-BC is better than the GPS ICA and comparable to the Galileo NeQuick model. We have found that the 95 percentiles of the prediction error are about 16.1, 16.1 and 13.4 TECU for the GPS ICA, Galileo NeQuick and NTCM-BC, respectively, during a selected quiet ionospheric period, whereas the corresponding numbers are found about 40.5, 28.2 and 26.5 TECU during a selected geomagnetic perturbed period. However, in terms of complexity the NTCM-BC is easier to handle than the Galileo NeQuick and in this respect comparable to the GPS ICA.

  13. An Oversampled Filter Bank Multicarrier System for cognitive Radio

    NARCIS (Netherlands)

    Kokkeler, Andre B.J.; Smit, Gerardus Johannes Maria; Zhang, Q; Zhang, Q.

    2008-01-01

    Due to small sideband power leakage, filter bank multicarrier techniques are considered as interesting alternatives to traditional OFDMs for spectrum pooling Cognitive Radio. In this paper, we propose an oversampled filter bank multicarrier system for Cognitive Radio. The increased spacing between

  14. Radio-controlled automatic gas meter-reading system; Releve automatique de compteur par radio

    Energy Technology Data Exchange (ETDEWEB)

    Yasui, M. [Osaka Gas Co., Ltd (Japan); Ishikawa, K.; Fujiwara, J. [Tokyo Gas Co., Ltd. (Japan); Ichihashi, T. [Toho Gas Co., Ltd. (Japan)

    2000-07-01

    In Japan, an automatic gas meter-reading system is in operation, also incorporating the functions of monitoring for abnormalities in gas use and remote-controlled emergency gas supply shutoff. This system has been realized by linking microcomputer-controlled gas meters(It's called 'Intelligent gas mater') equipped with automatic shutoff mechanism to the gas utility company operation center via communication lines. While the present system uses cable communication lines, we of Tokyo Gas Co., Ltd., Osaka Gas Co., Ltd. and Toho Gas Co., Ltd., have jointly developed a new system based on radio communication. This paper introduces this new system. While radio-controlled meter-reading systems are used in many countries around the world solely for automatic meter reading, our recently developed system is also capable of monitoring for abnormalities in gas use and remote-controlled emergency gas supply shutoff, thanks to its almost real-time two-way communication function. The new system can serve for a period of ten years without recharging. It is also characterized by its applicability as different systems according to purposes: 1) conventional automatic meter-reading system (terminal network control unit or T-NCU), 2) large-scale radio-controlled meter-reading system, and 3) portable terminal-type radio-controlled meter-reading system. (authors)

  15. Ultra-Wideband Tracking System Design for Relative Navigation

    Science.gov (United States)

    Ni, Jianjun David; Arndt, Dickey; Bgo, Phong; Dekome, Kent; Dusl, John

    2011-01-01

    This presentation briefly discusses a design effort for a prototype ultra-wideband (UWB) time-difference-of-arrival (TDOA) tracking system that is currently under development at NASA Johnson Space Center (JSC). The system is being designed for use in localization and navigation of a rover in a GPS deprived environment for surface missions. In one application enabled by the UWB tracking, a robotic vehicle carrying equipments can autonomously follow a crewed rover from work site to work site such that resources can be carried from one landing mission to the next thereby saving up-mass. The UWB Systems Group at JSC has developed a UWB TDOA High Resolution Proximity Tracking System which can achieve sub-inch tracking accuracy of a target within the radius of the tracking baseline [1]. By extending the tracking capability beyond the radius of the tracking baseline, a tracking system is being designed to enable relative navigation between two vehicles for surface missions. A prototype UWB TDOA tracking system has been designed, implemented, tested, and proven feasible for relative navigation of robotic vehicles. Future work includes testing the system with the application code to increase the tracking update rate and evaluating the linear tracking baseline to improve the flexibility of antenna mounting on the following vehicle.

  16. Global Navigation Satellite System and Augmentation

    Indian Academy of Sciences (India)

    aircraft-based augmentation system (ABAS). ... segment, the ground segment (or) control segment and the user segment ... control station (MCS), and ground antennas. ... repeatability, multipath rejection, size, profile, and environmental.

  17. Simple simulation training system for short-wave radio station

    Science.gov (United States)

    Tan, Xianglin; Shao, Zhichao; Tu, Jianhua; Qu, Fuqi

    2018-04-01

    The short-wave radio station is a most important transmission equipment of our signal corps, but in the actual teaching process, which exist the phenomenon of fewer equipment and more students, making the students' short-wave radio operation and practice time is very limited. In order to solve the above problems, to carry out shortwave radio simple simulation training system development is very necessary. This project is developed by combining hardware and software to simulate the voice communication operation and signal principle of shortwave radio station, and can test the signal flow of shortwave radio station. The test results indicate that this system is simple operation, human-machine interface friendly and can improve teaching more efficiency.

  18. 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.

  19. 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.

  20. Evaluation of Various Navigation System Concepts

    Science.gov (United States)

    1982-03-01

    Naigatimon aar01 N DAutomatic x xx Parallel 0fn x x x x x’ "OLeg t dung. n Mrankuhld M ni raia x N x to~g TAN is I OmuI,2 2mN 0 x "to - - -x...and must permit design of indicators and controls which can be directly interpreted or operated by the pilot at his normal station aboard the...the responsibility of control. The organization that controls the system can theoretically limit access to the system. Because VOVO/DME, Loran-C, and

  1. 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.

  2. A new evaluation platform for Navigation systems

    DEFF Research Database (Denmark)

    Sejerøe, Thomas Hanefeld; Poulsen, Niels Kjølstad; Ravn, Ole

    2005-01-01

    The KALMTOOL 2 toolbox is a set of MATLAB tools for state estimation for nonlinear systems. The toolbox contains functions for extended Kalman filtering as well as for two new filters called the DD1 filter and the DD2 filter. It also contains function for Uncented Kalman filters as well as three ...

  3. 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.

  4. Tele-auscultation support system with mixed reality navigation.

    Science.gov (United States)

    Hori, Kenta; Uchida, Yusuke; Kan, Tsukasa; Minami, Maya; Naito, Chisako; Kuroda, Tomohiro; Takahashi, Hideya; Ando, Masahiko; Kawamura, Takashi; Kume, Naoto; Okamoto, Kazuya; Takemura, Tadamasa; Yoshihara, Hiroyuki

    2013-01-01

    The aim of this research is to develop an information support system for tele-auscultation. In auscultation, a doctor requires to understand condition of applying a stethoscope, in addition to auscultatory sounds. The proposed system includes intuitive navigation system of stethoscope operation, in addition to conventional audio streaming system of auscultatory sounds and conventional video conferencing system for telecommunication. Mixed reality technology is applied for intuitive navigation of the stethoscope. Information, such as position, contact condition and breath, is overlaid on a view of the patient's chest. The contact condition of the stethoscope is measured by e-textile contact sensors. The breath is measured by a band type breath sensor. In a simulated tele-auscultation experiment, the stethoscope with the contact sensors and the breath sensor were evaluated. The results show that the presentation of the contact condition was not understandable enough for navigating the stethoscope handling. The time series of the breath phases was usable for the remote doctor to understand the breath condition of the patient.

  5. 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.

  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. Letting in-vehicle navigation lead the way: Older drivers' perceptions of and ability to follow a GPS navigation system.

    Science.gov (United States)

    Stinchcombe, Arne; Gagnon, Sylvain; Kateb, Matthew; Curtis, Meredith; Porter, Michelle M; Polgar, Jan; Bédard, Michel

    2017-09-01

    In-vehicle navigation systems have the potential to simplify the driving task by reducing the drivers' need to engage in wayfinding, especially in unfamiliar environments. This study sought to characterize older drivers' overall assessment of using in-vehicle GPS technology as part of a research study and to explore whether the use of this technology has an impact on participants' driving behaviour. Forty-seven older drivers completed an on-road evaluation where directions were provided by an in-vehicle GPS navigation system and their behaviour was recorded using video technology. They later completed a questionnaire to assess their perception of the navigation system. After the study, participants were grouped based on whether they were able to accurately follow the instructions provided by the navigation system. The results indicated that most drivers were satisfied with the navigation technology and found the directions it provided to be clear. There were no statistically significant differences in the number of on-road errors committed by drivers who did not follow the directions from the navigation system in comparison to drivers who did follow the directions. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Solar system radio astronomy at low frequencies

    International Nuclear Information System (INIS)

    Desch, M.D.

    1987-01-01

    The planetary radio-astronomy observations obtained with the two Voyager spacecraft since their launch in 1977 are briefly characterized and illustrated with graphs, diagrams, and sample spectra. Topics addressed include the spacecraft designs and trajectories, the wavelength coverage of the radio instruments, the Io-controlled LF emission of Jupiter, the solar-wind effect on the Saturn kilometric radiation, the Saturn electrostatic discharges, and the use of the clocklike feature of the Uranus emission to measure the planet's rotation period. 23 references

  9. Towards Energy Efficient Cognitive Radio Systems

    KAUST Repository

    Alabbasi, AbdulRahman

    2016-07-14

    Cognitive radio (CR) is a cutting-edge wireless communication technology that adopts several existing communication concepts in order to efficiently utilize the spectrum and meet the users demands of high throughput and real-time systems. Conventionally, high throughput demands are met through adopting broadband and multi-antenna technologies such as, orthogonal frequency division multiplexing (OFDM) and Multi-Input Multi-Output (MIMO). Whereas, real-time application demands are met by analyzing metrics which characterize the delay limited channels, such as, outage probability over block-fading channels. Being an environmental friendly technology, energy efficiency metrics should be considered in the design of a CR application. This thesis tackles the energy efficiency of CR system from different aspects, utilizing different measuring metrics and constrains. Under the single-input single-output (SISO) OFDM we minimized the energy per goodbit (EPG) metric subject to several power and Quality of Service (QoS) constraints. In this approach, the minimum EPG metric is optimized via proposing two optimal and sub-optimal resource allocation schemes. We consider several parameters as optimization variables, such as, power policy, sensing threshold, and channel quality threshold. We also captured the impact of involving the media access control (MAC) layers parameters, such as, frame length, in the minimization of a modified EPG metric. Also, a MAC protocol, i.e., hybrid automatic repeat request (HARQ), and the associated power consumption of the retransmission mechanism is considered in the formulation of the problem. In this context, the optimal power and frame length are derived to minimize the modified EPG while considering several spectrum-sharing scenarios, which depend on sensing information. In MIMO based CR system, we maximized capacity to power ratio (CPR) (as an energy efficiency (EE) metric) subject to several power and QoS constraints. In this context, the

  10. Advantages of Hybrid Global Navigation Satellite Systems

    Directory of Open Access Journals (Sweden)

    Asim Bilajbegović

    2007-05-01

    Full Text Available In a decision-making situation, what kind of GPS equipment to purchase, one always has a dilemma, tobuy hybrid (GPS+GLONASS or only GPS receivers? In the case of completeness of the GLONASS satellite system, this dilemma probably would not have existed. The answer to this dilemma is given in the present paper, but for the constellation of the GLONASS satellites in summer 2006 (14 satellites operational. Due to the short operational period of these satellites (for example GLONASS-M, 5 years, and not launching new ones, at this moment (February 25, 2007, only 10 satellites are operational. For the sake of research and giving answers to these questions, about 252 RTK measurements have been done using (GPS and GNSS receivers, on points with different obstructions of horizon. Besides that, initialisation time has been investigated for both systems from about 480 measurements, using rover's antenna with metal cover, during a time interval of 0.5, 2 and 5 seconds. Moreover, accuracy, firmware declared accuracy and redundancy of GPS and GNSS RTK measurements have been investigating.  

  11. Canoe: An Autonomous Infrastructure-Free Indoor Navigation System

    Directory of Open Access Journals (Sweden)

    Kai Dong

    2017-04-01

    Full Text Available The development of the Internet of Things (IoT has accelerated research in indoor navigation systems, a majority of which rely on adequate wireless signals and sources. Nonetheless, deploying such a system requires periodic site-survey, which is time consuming and labor intensive. To address this issue, in this paper we present Canoe, an indoor navigation system that considers shopping mall scenarios. In our system, we do not assume any prior knowledge, such as floor-plan or the shop locations, access point placement or power settings, historical RSS measurements or fingerprints, etc. Instead, Canoe requires only that the shop owners collect and publish RSS values at the entrances of their shops and can direct a consumer to any of these shops by comparing the observed RSS values. The locations of the consumers and the shops are estimated using maximum likelihood estimation. In doing this, the direction of the target shop relative to the current orientation of the consumer can be precisely computed, such that the direction that a consumer should move can be determined. We have conducted extensive simulations using a real-world dataset. Our experiments in a real shopping mall demonstrate that if 50% of the shops publish their RSS values, Canoe can precisely navigate a consumer within 30 s, with an error rate below 9%.

  12. High accuracy autonomous navigation using the global positioning system (GPS)

    Science.gov (United States)

    Truong, Son H.; Hart, Roger C.; Shoan, Wendy C.; Wood, Terri; Long, Anne C.; Oza, Dipak H.; Lee, Taesul

    1997-01-01

    The application of global positioning system (GPS) technology to the improvement of the accuracy and economy of spacecraft navigation, is reported. High-accuracy autonomous navigation algorithms are currently being qualified in conjunction with the GPS attitude determination flyer (GADFLY) experiment for the small satellite technology initiative Lewis spacecraft. Preflight performance assessments indicated that these algorithms are able to provide a real time total position accuracy of better than 10 m and a velocity accuracy of better than 0.01 m/s, with selective availability at typical levels. It is expected that the position accuracy will be increased to 2 m if corrections are provided by the GPS wide area augmentation system.

  13. Autonomous navigation system for mobile robots of inspection

    International Nuclear Information System (INIS)

    Angulo S, P.; Segovia de los Rios, A.

    2005-01-01

    One of the goals in robotics is the human personnel's protection that work in dangerous areas or of difficult access, such it is the case of the nuclear industry where exist areas that, for their own nature, they are inaccessible for the human personnel, such as areas with high radiation level or high temperatures; it is in these cases where it is indispensable the use of an inspection system that is able to carry out a sampling of the area in order to determine if this areas can be accessible for the human personnel. In this situation it is possible to use an inspection system based on a mobile robot, of preference of autonomous navigation, for the realization of such inspection avoiding by this way the human personnel's exposure. The present work proposes a model of autonomous navigation for a mobile robot Pioneer 2-D Xe based on the algorithm of wall following using the paradigm of fuzzy logic. (Author)

  14. The PPP Precision Analysis Based on BDS Regional Navigation System

    Directory of Open Access Journals (Sweden)

    ZHU Yongxing

    2015-04-01

    Full Text Available BeiDou navigation satellite system(BDS has opened service in most of the Asia-Pacific region, it offers the possibility to break the technological monopoly of GPS in the field of high-precision applications, so its performance of precise point positioning (PPP has been a great concern. Firstly, the constellation of BeiDou regional navigation system and BDS/GPS tracking network is introduced. Secondly, the precise ephemeris and clock offset accuracy of BeiDou satellite based on domestic tracking network is analyzed. Finally, the static and kinematic PPP accuracy is studied, and compared with the GPS. The actual measured numerical example shows that the static and kinematic PPP based on BDS can achieve centimeter-level and decimeter-level respectively, reaching the current level of GPS precise point positioning.

  15. Significance of Waterway Navigation Positioning Systems On Ship's Manoeuvring Safety

    Science.gov (United States)

    Galor, W.

    The main goal of navigation is to lead the ship to the point of destination safety and efficiently. Various factors may affect ship realisating this process. The ship movement on waterway are mainly limited by water area dimensions (surface and depth). These limitations cause the requirement to realise the proper of ship movement trajectory. In case when this re requirement cant't fulfil then marine accident may happend. This fact is unwanted event caused losses of human health and life, damage or loss of cargo and ship, pollution of natural environment, damage of port structures or blocking the port of its ports and lost of salvage operation. These losses in same cases can be catas- trophical especially while e.i. crude oil spilling could be place. To realise of safety navigation process is needed to embrace the ship's movement trajectory by waterways area. The ship's trajectory is described by manoeuvring lane as a surface of water area which is require to realise of safety ship movement. Many conditions affect to ship manoeuvring line. The main are following: positioning accuracy, ship's manoeuvring features and phenomena's of shore and ship's bulk common affecting. The accuracy of positioning system is most important. This system depends on coast navigation mark- ing which can range many kinds of technical realisation. Mainly used systems based on lights (line), radionavigation (local system or GPS, DGPS), or radars. If accuracy of positiong is higer, then safety of navigation is growing. This article presents these problems exemplifying with approaching channel to ports situated on West Pomera- nian water region.

  16. Robust low-frequency spread-spectrum navigation system

    Science.gov (United States)

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

    2009-12-01

    Methods and apparatus are described for a navigation system. A process includes providing a plurality of transmitters distributed throughout a desired coverage area; locking the plurality of transmitters to a common timing reference; transmitting a signal from each of the plurality of transmitters. An apparatus includes a plurality of transmitters distributed throughout a desired coverage area; wherein each of the plurality of transmitters comprises a packet generator; and wherein the plurality of transmitters are locked to a common timing reference.

  17. An intelligent navigation system for an unmanned surface vehicle

    OpenAIRE

    Xu , Tao

    2007-01-01

    Merged with duplicate record 10026.1/2768 on 27.03.2017 by CS (TIS) A multi-disciplinary research project has been carried out at the University of Plymouth to design and develop an Unmanned Surface Vehicle (USV) named ýpringer. The work presented herein relates to formulation of a robust, reliable, accurate and adaptable navigation system to enable opringei to undertake various environmental monitoring tasks. Synergistically, sensor mathematical modelling, fuzzy logic, Multi-S...

  18. Ground-Based Global Navigation Satellite System (GNSS) GLONASS Broadcast Ephemeris Data (hourly files) from NASA CDDIS

    Data.gov (United States)

    National Aeronautics and Space Administration — This dataset consists of ground-based Global Navigation Satellite System (GNSS) GLObal NAvigation Satellite System (GLONASS) Broadcast Ephemeris Data (hourly files)...

  19. Ground-Based Global Navigation Satellite System Data (30-second sampling, 1 hour files) from NASA CDDIS

    Data.gov (United States)

    National Aeronautics and Space Administration — Global Navigation Satellite System (GNSS) daily 30-second sampled data available from the Crustal Dynamics Data Information System (CDDIS). Global Navigation...

  20. 47 CFR 15.211 - Tunnel radio systems.

    Science.gov (United States)

    2010-10-01

    ... regulations contained within this part. (c) The total electromagnetic field from a tunnel radio system on any... surrounding earth and/or water. (b) Any intentional or unintentional radiator external to the tunnel, mine or...

  1. Location-based resource allocation for OFDMA cognitive radio systems

    KAUST Repository

    Nam, Haewoon; Ben Ghorbel, Mahdi; Alouini, Mohamed-Slim

    2010-01-01

    In cognitive radio systems, in order for the secondary users to opportunistically share the spectrum without interfering the primary users, an accurate spectrum measurement and a precise estimation of the interference at the primary users

  2. A Visual-Aided Inertial Navigation and Mapping System

    Directory of Open Access Journals (Sweden)

    Rodrigo Munguía

    2016-05-01

    Full Text Available State estimation is a fundamental necessity for any application involving autonomous robots. This paper describes a visual-aided inertial navigation and mapping system for application to autonomous robots. The system, which relies on Kalman filtering, is designed to fuse the measurements obtained from a monocular camera, an inertial measurement unit (IMU and a position sensor (GPS. The estimated state consists of the full state of the vehicle: the position, orientation, their first derivatives and the parameter errors of the inertial sensors (i.e., the bias of gyroscopes and accelerometers. The system also provides the spatial locations of the visual features observed by the camera. The proposed scheme was designed by considering the limited resources commonly available in small mobile robots, while it is intended to be applied to cluttered environments in order to perform fully vision-based navigation in periods where the position sensor is not available. Moreover, the estimated map of visual features would be suitable for multiple tasks: i terrain analysis; ii three-dimensional (3D scene reconstruction; iii localization, detection or perception of obstacles and generating trajectories to navigate around these obstacles; and iv autonomous exploration. In this work, simulations and experiments with real data are presented in order to validate and demonstrate the performance of the proposal.

  3. An adaptive software defined radio design based on a standard space telecommunication radio system API

    Science.gov (United States)

    Xiong, Wenhao; Tian, Xin; Chen, Genshe; Pham, Khanh; Blasch, Erik

    2017-05-01

    Software defined radio (SDR) has become a popular tool for the implementation and testing for communications performance. The advantage of the SDR approach includes: a re-configurable design, adaptive response to changing conditions, efficient development, and highly versatile implementation. In order to understand the benefits of SDR, the space telecommunication radio system (STRS) was proposed by NASA Glenn research center (GRC) along with the standard application program interface (API) structure. Each component of the system uses a well-defined API to communicate with other components. The benefit of standard API is to relax the platform limitation of each component for addition options. For example, the waveform generating process can support a field programmable gate array (FPGA), personal computer (PC), or an embedded system. As long as the API defines the requirements, the generated waveform selection will work with the complete system. In this paper, we demonstrate the design and development of adaptive SDR following the STRS and standard API protocol. We introduce step by step the SDR testbed system including the controlling graphic user interface (GUI), database, GNU radio hardware control, and universal software radio peripheral (USRP) tranceiving front end. In addition, a performance evaluation in shown on the effectiveness of the SDR approach for space telecommunication.

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

    National Research Council Canada - National Science Library

    Crawford, Matthew P

    2006-01-01

    With much of the military and civilian communities becoming dependent on GPS technology to navigate it has become imperative that the navigation systems be tested in situations in which GPS does not work...

  5. Ground-Based Global Navigation Satellite System Combined Broadcast Ephemeris Data (daily files) from NASA CDDIS

    Data.gov (United States)

    National Aeronautics and Space Administration — This dataset consists of ground-based Global Navigation Satellite System (GNSS) Combined Broadcast Ephemeris Data (daily files of all distinct navigation messages...

  6. Individual Global Navigation Satellite Systems in the Space Service Volume

    Science.gov (United States)

    Force, Dale A.

    2015-01-01

    Besides providing position, navigation, and timing (PNT) to terrestrial users, GPS is currently used to provide for precision orbit determination, precise time synchronization, real-time spacecraft navigation, and three-axis control of Earth orbiting satellites. With additional Global Navigation Satellite Systems (GNSS) coming into service (GLONASS, Beidou, and Galileo), it will be possible to provide these services by using other GNSS constellations. The paper, "GPS in the Space Service Volume," presented at the ION GNSS 19th International Technical Meeting in 2006 (Ref. 1), defined the Space Service Volume, and analyzed the performance of GPS out to 70,000 km. This paper will report a similar analysis of the performance of each of the additional GNSS and compare them with GPS alone. The Space Service Volume, defined as the volume between 3,000 km altitude and geosynchronous altitude, as compared with the Terrestrial Service Volume between the surface and 3,000 km. In the Terrestrial Service Volume, GNSS performance will be similar to performance on the Earth's surface. The GPS system has established signal requirements for the Space Service Volume. A separate paper presented at the conference covers the use of multiple GNSS in the Space Service Volume.

  7. Telecommunications and navigation systems design for manned Mars exploration missions

    Science.gov (United States)

    Hall, Justin R.; Hastrup, Rolf C.

    1989-06-01

    This paper discusses typical manned Mars exploration needs for telecommunications, including preliminary navigation support functions. It is a brief progress report on an ongoing study program within the current NASA JPL Deep Space Network (DSN) activities. A typical Mars exploration case is defined, and support approaches comparing microwave and optical frequency performance for both local in situ and Mars-earth links are described. Optical telecommunication and navigation technology development opportunities in a Mars exploration program are also identified. A local Mars system telecommunication relay and navigation capability for service support of all Mars missions has been proposed as part of an overall solar system communications network. The effects of light-time delay and occultations on real-time mission decision-making are discussed; the availability of increased local mass data storage may be more important than increasing peak data rates to earth. The long-term frequency use plan will most likely include a mix of microwave, millimeter-wave and optical link capabilities to meet a variety of deep space mission needs.

  8. Urban, Indoor and Subterranean Navigation Sensors and Systems (Capteurs et systemes de navigation urbains, interieurs et souterrains)

    Science.gov (United States)

    2010-11-01

    3-10 Multiple Images of an Image Sequence Figure 3-10 A Digital Magnetic Compass from KVH Industries 3-11 Figure 3-11 Earth’s Magnetic Field 3-11...ARINO SENER – Ingenieria y Sistemas S.A Aerospace Division Parque Tecnologico de Madrid Calle Severo Ocho 4 28760 Tres Cantos Madrid Email...experts from government, academia, industry and the military produced an analysis of future navigation sensors and systems whose performance

  9. METHODS AND MEANS OF MEASURING THE COORDINATES OF AIRCRAFTS BY TIME DELAY OF SIGNALS IN MULTIPOSITIONING RADIO RANGEFINDING AERONAVIGATION AND LANDING SYSTEMS

    Directory of Open Access Journals (Sweden)

    Ya. V. Kondrashov

    2014-01-01

    Full Text Available The principles of operation of radio range finding interrogation-reply system to provide navigational and landing operations of aircraft are considered. A precise method of measuring of time delays of signals for determining the location of aircraft with high accuracy is proposed.

  10. Applications of radio frequency identification systems in the mining industry

    Energy Technology Data Exchange (ETDEWEB)

    Hind, D J [Davis Derby Ltd., Derby (United Kingdom)

    1994-01-01

    Radio Frequency Identification Systems (RFID) are one of the automatic data capture technologies taking over from bar codes and magnetic swipe cards in many applications involving automatic hands free operation in arduous environments. RFID systems are based on the use of miniature radio transponders carrying encoded electronic data that is used to uniquely identify the identity of transponders. The paper reviews the types of system available and compares the various techniques involved in the different systems. The various types of transponder are described including the latest state of the art passive read/write high performance types. The problems involved in designing and certifying a system for use in hazardous areas are described, with particular reference to the problems of inadvertent detonator ignition by radio systems. Applications of RFID systems in the mining industry are described, covering applications both on the surface and underground. 1 ref., 10 figs.

  11. Cyber security with radio frequency interferences mitigation study for satellite systems

    Science.gov (United States)

    Wang, Gang; Wei, Sixiao; Chen, Genshe; Tian, Xin; Shen, Dan; Pham, Khanh; Nguyen, Tien M.; Blasch, Erik

    2016-05-01

    Satellite systems including the Global Navigation Satellite System (GNSS) and the satellite communications (SATCOM) system provide great convenience and utility to human life including emergency response, wide area efficient communications, and effective transportation. Elements of satellite systems incorporate technologies such as navigation with the global positioning system (GPS), satellite digital video broadcasting, and information transmission with a very small aperture terminal (VSAT), etc. The satellite systems importance is growing in prominence with end users' requirement for globally high data rate transmissions; the cost reduction of launching satellites; development of smaller sized satellites including cubesat, nanosat, picosat, and femtosat; and integrating internet services with satellite networks. However, with the promising benefits, challenges remain to fully develop secure and robust satellite systems with pervasive computing and communications. In this paper, we investigate both cyber security and radio frequency (RF) interferences mitigation for satellite systems, and demonstrate that they are not isolated. The action space for both cyber security and RF interferences are firstly summarized for satellite systems, based on which the mitigation schemes for both cyber security and RF interferences are given. A multi-layered satellite systems structure is provided with cross-layer design considering multi-path routing and channel coding, to provide great security and diversity gains for secure and robust satellite systems.

  12. Atrial Fibrillation Ablation Guided by a Novel Nonfluoroscopic Navigation System.

    Science.gov (United States)

    Ballesteros, Gabriel; Ramos, Pablo; Neglia, Renzo; Menéndez, Diego; García-Bolao, Ignacio

    2017-09-01

    Rhythmia is a new nonfluoroscopic navigation system that is able to create high-density electroanatomic maps. The aim of this study was to describe the acute outcomes of atrial fibrillation (AF) ablation guided by this system, to analyze the volume provided by its electroanatomic map, and to describe its ability to locate pulmonary vein (PV) reconnection gaps in redo procedures. This observational study included 62 patients who underwent AF ablation with Rhythmia compared with a retrospective cohort who underwent AF ablation with a conventional nonfluoroscopic navigation system (Ensite Velocity). The number of surface electrograms per map was significantly higher in Rhythmia procedures (12 125 ± 2826 vs 133 ± 21 with Velocity; P < .001), with no significant differences in the total procedure time. The Orion catheter was placed for mapping in 99.5% of PV (95.61% in the control group with a conventional circular mapping catheter; P = .04). There were no significant differences in the percentage of PV isolation between the 2 groups. In redo procedures, an ablation gap could be identified on the activation map in 67% of the reconnected PV (40% in the control group; P = .042). The measured left atrial volume was lower than that calculated by computed tomography (109.3 v 15.2 and 129.9 ± 13.2 mL, respectively; P < .001). There were no significant differences in the number of complications. The Rhythmia system is effective for AF ablation procedures, with procedure times and safety profiles similar to conventional nonfluoroscopic navigation systems. In redo procedures, it appears to be more effective in identifying reconnected PV conduction gaps. Copyright © 2016 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

  13. Development of an advanced intelligent robot navigation system

    International Nuclear Information System (INIS)

    Hai Quan Dai; Dalton, G.R.; Tulenko, J.; Crane, C.C. III

    1992-01-01

    As part of the US Department of Energy's Robotics for Advanced Reactors Project, the authors are in the process of assembling an advanced intelligent robotic navigation and control system based on previous work performed on this project in the areas of computer control, database access, graphical interfaces, shared data and computations, computer vision for positions determination, and sonar-based computer navigation systems. The system will feature three levels of goals: (1) high-level system for management of lower level functions to achieve specific functional goals; (2) intermediate level of goals such as position determination, obstacle avoidance, and discovering unexpected objects; and (3) other supplementary low-level functions such as reading and recording sonar or video camera data. In its current phase, the Cybermotion K2A mobile robot is not equipped with an onboard computer system, which will be included in the final phase. By that time, the onboard system will play important roles in vision processing and in robotic control communication

  14. 76 FR 77939 - Proposed Provision of Navigation Services for the Next Generation Air Transportation System...

    Science.gov (United States)

    2011-12-15

    ... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Parts 91, 121, 125, 129, and 135 Proposed Provision of Navigation Services for the Next Generation Air Transportation System (Next...) navigation infrastructure to enable performance-based navigation (PBN) as part of the Next Generation Air...

  15. Global navigation satellite systems performance analysis and augmentation strategies in aviation

    Science.gov (United States)

    Sabatini, Roberto; Moore, Terry; Ramasamy, Subramanian

    2017-11-01

    In an era of significant air traffic expansion characterized by a rising congestion of the radiofrequency spectrum and a widespread introduction of Unmanned Aircraft Systems (UAS), Global Navigation Satellite Systems (GNSS) are being exposed to a variety of threats including signal interferences, adverse propagation effects and challenging platform-satellite relative dynamics. Thus, there is a need to characterize GNSS signal degradations and assess the effects of interfering sources on the performance of avionics GNSS receivers and augmentation systems used for an increasing number of mission-essential and safety-critical aviation tasks (e.g., experimental flight testing, flight inspection/certification of ground-based radio navigation aids, wide area navigation and precision approach). GNSS signal deteriorations typically occur due to antenna obscuration caused by natural and man-made obstructions present in the environment (e.g., elevated terrain and tall buildings when flying at low altitude) or by the aircraft itself during manoeuvring (e.g., aircraft wings and empennage masking the on-board GNSS antenna), ionospheric scintillation, Doppler shift, multipath, jamming and spurious satellite transmissions. Anyone of these phenomena can result in partial to total loss of tracking and possible tracking errors, depending on the severity of the effect and the receiver characteristics. After designing GNSS performance threats, the various augmentation strategies adopted in the Communication, Navigation, Surveillance/Air Traffic Management and Avionics (CNS + A) context are addressed in detail. GNSS augmentation can take many forms but all strategies share the same fundamental principle of providing supplementary information whose objective is improving the performance and/or trustworthiness of the system. Hence it is of paramount importance to consider the synergies offered by different augmentation strategies including Space Based Augmentation System (SBAS), Ground

  16. IMPELEMENTASI SISTEM PEMANTAUAN OBJEK BERGERAK DENGAN MEMANFAATKAN FREKUENSI RADIO MENGGUNAKAN GPS (GLOBAL POSITIONING SYSTEM

    Directory of Open Access Journals (Sweden)

    Budi Triandi

    2010-05-01

    Full Text Available GPS was developed by the United States Department of Defense as a reliable means for accurate navigation. The system provides highly accurate position and velocity information and precise time on a continuous global basis to an unlimited number of properly equipped users. By using combined GPS receiver and microcontroller together with radio system, we can design a monitoring system for our vehicles and display the result on the computer. This system consists of a master module that transmits and receives signals from computer and two slave modules to collect GPS data from vehicles. The result of experiment shows that this system is able to track the vehicle on digital map with accuracy as high as 95%.Keywords: GPS, microcontroller, monitoring, RF

  17. IMPROVING CAR NAVIGATION WITH A VISION-BASED SYSTEM

    Directory of Open Access Journals (Sweden)

    H. Kim

    2015-08-01

    Full Text Available The real-time acquisition of the accurate positions is very important for the proper operations of driver assistance systems or autonomous vehicles. Since the current systems mostly depend on a GPS and map-matching technique, they show poor and unreliable performance in blockage and weak areas of GPS signals. In this study, we propose a vision oriented car navigation method based on sensor fusion with a GPS and in-vehicle sensors. We employed a single photo resection process to derive the position and attitude of the camera and thus those of the car. This image georeferencing results are combined with other sensory data under the sensor fusion framework for more accurate estimation of the positions using an extended Kalman filter. The proposed system estimated the positions with an accuracy of 15 m although GPS signals are not available at all during the entire test drive of 15 minutes. The proposed vision based system can be effectively utilized for the low-cost but high-accurate and reliable navigation systems required for intelligent or autonomous vehicles.

  18. Improving Car Navigation with a Vision-Based System

    Science.gov (United States)

    Kim, H.; Choi, K.; Lee, I.

    2015-08-01

    The real-time acquisition of the accurate positions is very important for the proper operations of driver assistance systems or autonomous vehicles. Since the current systems mostly depend on a GPS and map-matching technique, they show poor and unreliable performance in blockage and weak areas of GPS signals. In this study, we propose a vision oriented car navigation method based on sensor fusion with a GPS and in-vehicle sensors. We employed a single photo resection process to derive the position and attitude of the camera and thus those of the car. This image georeferencing results are combined with other sensory data under the sensor fusion framework for more accurate estimation of the positions using an extended Kalman filter. The proposed system estimated the positions with an accuracy of 15 m although GPS signals are not available at all during the entire test drive of 15 minutes. The proposed vision based system can be effectively utilized for the low-cost but high-accurate and reliable navigation systems required for intelligent or autonomous vehicles.

  19. Lunar Navigator - A Miniature, Fully Autonomous, Lunar Navigation, Surveyor, and Range Finder System, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Microcosm will use existing hardware and software from related programs to create a prototype Lunar Navigation Sensor (LNS) early in Phase II, such that most of the...

  20. Lunar Navigator - A Miniature, Fully Autonomous, Lunar Navigation, Surveyor, and Range Finder System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Microcosm proposes to design and develop a fully autonomous Lunar Navigator based on our MicroMak miniature star sensor and a gravity gradiometer similar to one on a...

  1. Applications of radio frequency identification systems in the mining industry

    Energy Technology Data Exchange (ETDEWEB)

    Hind, D [Davis Derby Limited (United Kingdom)

    1994-12-31

    The paper describes the application of Radio Frequency Identification (RFID) systems in the mining industry for both surface and underground mines. The history of the RFID system, types available, the transponder, and the various techniques used are described and compared. The design and certification of a system for use in a hazardous area are described, noting the hazard of inadvertent detonator ignition. 2 refs.

  2. A Novel Augmented Reality Navigation System for Endoscopic Sinus and Skull Base Surgery: A Feasibility Study.

    Directory of Open Access Journals (Sweden)

    Liang Li

    Full Text Available To verify the reliability and clinical feasibility of a self-developed navigation system based on an augmented reality technique for endoscopic sinus and skull base surgery.In this study we performed a head phantom and cadaver experiment to determine the display effect and accuracy of our navigational system. We compared cadaver head-based simulated operations, the target registration error, operation time, and National Aeronautics and Space Administration Task Load Index scores of our navigation system to conventional navigation systems.The navigation system developed in this study has a novel display mode capable of fusing endoscopic images to three-dimensional (3-D virtual images. In the cadaver head experiment, the target registration error was 1.28 ± 0.45 mm, which met the accepted standards of a navigation system used for nasal endoscopic surgery. Compared with conventional navigation systems, the new system was more effective in terms of operation time and the mental workload of surgeons, which is especially important for less experienced surgeons.The self-developed augmented reality navigation system for endoscopic sinus and skull base surgery appears to have advantages that outweigh those of conventional navigation systems. We conclude that this navigational system will provide rhinologists with more intuitive and more detailed imaging information, thus reducing the judgment time and mental workload of surgeons when performing complex sinus and skull base surgeries. Ultimately, this new navigational system has potential to increase the quality of surgeries. In addition, the augmented reality navigational system could be of interest to junior doctors being trained in endoscopic techniques because it could speed up their learning. However, it should be noted that the navigation system serves as an adjunct to a surgeon's skills and knowledge, not as a substitute.

  3. A Novel Augmented Reality Navigation System for Endoscopic Sinus and Skull Base Surgery: A Feasibility Study

    Science.gov (United States)

    Li, Liang; Yang, Jian; Chu, Yakui; Wu, Wenbo; Xue, Jin; Liang, Ping; Chen, Lei

    2016-01-01

    Objective To verify the reliability and clinical feasibility of a self-developed navigation system based on an augmented reality technique for endoscopic sinus and skull base surgery. Materials and Methods In this study we performed a head phantom and cadaver experiment to determine the display effect and accuracy of our navigational system. We compared cadaver head-based simulated operations, the target registration error, operation time, and National Aeronautics and Space Administration Task Load Index scores of our navigation system to conventional navigation systems. Results The navigation system developed in this study has a novel display mode capable of fusing endoscopic images to three-dimensional (3-D) virtual images. In the cadaver head experiment, the target registration error was 1.28 ± 0.45 mm, which met the accepted standards of a navigation system used for nasal endoscopic surgery. Compared with conventional navigation systems, the new system was more effective in terms of operation time and the mental workload of surgeons, which is especially important for less experienced surgeons. Conclusion The self-developed augmented reality navigation system for endoscopic sinus and skull base surgery appears to have advantages that outweigh those of conventional navigation systems. We conclude that this navigational system will provide rhinologists with more intuitive and more detailed imaging information, thus reducing the judgment time and mental workload of surgeons when performing complex sinus and skull base surgeries. Ultimately, this new navigational system has potential to increase the quality of surgeries. In addition, the augmented reality navigational system could be of interest to junior doctors being trained in endoscopic techniques because it could speed up their learning. However, it should be noted that the navigation system serves as an adjunct to a surgeon’s skills and knowledge, not as a substitute. PMID:26757365

  4. Architectural elements of hybrid navigation systems for future space transportation

    Science.gov (United States)

    Trigo, Guilherme F.; Theil, Stephan

    2017-12-01

    The fundamental limitations of inertial navigation, currently employed by most launchers, have raised interest for GNSS-aided solutions. Combination of inertial measurements and GNSS outputs allows inertial calibration online, solving the issue of inertial drift. However, many challenges and design options unfold. In this work we analyse several architectural elements and design aspects of a hybrid GNSS/INS navigation system conceived for space transportation. The most fundamental architectural features such as coupling depth, modularity between filter and inertial propagation, and open-/closed-loop nature of the configuration, are discussed in the light of the envisaged application. Importance of the inertial propagation algorithm and sensor class in the overall system are investigated, being the handling of sensor errors and uncertainties that arise with lower grade sensory also considered. In terms of GNSS outputs we consider receiver solutions (position and velocity) and raw measurements (pseudorange, pseudorange-rate and time-difference carrier phase). Receiver clock error handling options and atmospheric error correction schemes for these measurements are analysed under flight conditions. System performance with different GNSS measurements is estimated through covariance analysis, being the differences between loose and tight coupling emphasized through partial outage simulation. Finally, we discuss options for filter algorithm robustness against non-linearities and system/measurement errors. A possible scheme for fault detection, isolation and recovery is also proposed.

  5. Architectural elements of hybrid navigation systems for future space transportation

    Science.gov (United States)

    Trigo, Guilherme F.; Theil, Stephan

    2018-06-01

    The fundamental limitations of inertial navigation, currently employed by most launchers, have raised interest for GNSS-aided solutions. Combination of inertial measurements and GNSS outputs allows inertial calibration online, solving the issue of inertial drift. However, many challenges and design options unfold. In this work we analyse several architectural elements and design aspects of a hybrid GNSS/INS navigation system conceived for space transportation. The most fundamental architectural features such as coupling depth, modularity between filter and inertial propagation, and open-/closed-loop nature of the configuration, are discussed in the light of the envisaged application. Importance of the inertial propagation algorithm and sensor class in the overall system are investigated, being the handling of sensor errors and uncertainties that arise with lower grade sensory also considered. In terms of GNSS outputs we consider receiver solutions (position and velocity) and raw measurements (pseudorange, pseudorange-rate and time-difference carrier phase). Receiver clock error handling options and atmospheric error correction schemes for these measurements are analysed under flight conditions. System performance with different GNSS measurements is estimated through covariance analysis, being the differences between loose and tight coupling emphasized through partial outage simulation. Finally, we discuss options for filter algorithm robustness against non-linearities and system/measurement errors. A possible scheme for fault detection, isolation and recovery is also proposed.

  6. Wellbore inertial navigation system (WINS) software development and test results

    Energy Technology Data Exchange (ETDEWEB)

    Wardlaw, R. Jr.

    1982-09-01

    The structure and operation of the real-time software developed for the Wellbore Inertial Navigation System (WINS) application are described. The procedure and results of a field test held in a 7000-ft well in the Nevada Test Site are discussed. Calibration and instrumentation error compensation are outlined, as are design improvement areas requiring further test and development. Notes on Kalman filtering and complete program listings of the real-time software are included in the Appendices. Reference is made to a companion document which describes the downhole instrumentation package.

  7. Modems for emerging digital cellular-mobile radio system

    Science.gov (United States)

    Feher, Kamilo

    1991-01-01

    Digital modem techniques for emerging digital cellular telecommunications-mobile radio system applications are described and analyzed. In particular, theoretical performance, experimental results, principles of operation, and various architectures of pi/4-QPSK (pi/4-shifted coherent or differential QPSK) modems for second-generation US digital cellular radio system applications are presented. The spectral/power efficiency and performance of the pi/4-QPSK modems (American and Japanese digital cellular emerging standards) are studied and briefly compared to GMSK (Gaussian minimum-shift keying) modems (proposed for European DECT and GSM cellular standards). Improved filtering strategies and digital pilot-aided (digital channel sounding) techniques are also considered for pi/4-QPSK and other digital modems. These techniques could significantly improve the performance of digital cellular and other digital land mobile and satellite mobile radio systems. More spectrally efficient modem trends for future cellular/mobile (land mobile) and satellite communication systems applications are also highlighted.

  8. 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

  9. An Optical Receiver Post Processing System for the Integrated Radio and Optical Communications Software Defined Radio Test Bed

    Science.gov (United States)

    Nappier, Jennifer M.; Tokars, Roger P.; Wroblewski, Adam C.

    2016-01-01

    The Integrated Radio and Optical Communications (iROC) project at the National Aeronautics and Space Administrations (NASA) Glenn Research Center is investigating the feasibility of a hybrid radio frequency (RF) and optical communication system for future deep space missions. As a part of this investigation, a test bed for a radio frequency (RF) and optical software defined radio (SDR) has been built. Receivers and modems for the NASA deep space optical waveform are not commercially available so a custom ground optical receiver system has been built. This paper documents the ground optical receiver, which is used in order to test the RF and optical SDR in a free space optical communications link.

  10. An Optical Receiver Post-Processing System for the Integrated Radio and Optical Communications Software Defined Radio Test Bed

    Science.gov (United States)

    Nappier, Jennifer M.; Tokars, Roger P.; Wroblewski, Adam C.

    2016-01-01

    The Integrated Radio and Optical Communications (iROC) project at the National Aeronautics and Space Administration's (NASA) Glenn Research Center is investigating the feasibility of a hybrid radio frequency (RF) and optical communication system for future deep space missions. As a part of this investigation, a test bed for a radio frequency (RF) and optical software defined radio (SDR) has been built. Receivers and modems for the NASA deep space optical waveform are not commercially available so a custom ground optical receiver system has been built. This paper documents the ground optical receiver, which is used in order to test the RF and optical SDR in a free space optical communications link.

  11. Considerations for the Next Revision of NASA's Space Telecommunications Radio System Architecture

    Science.gov (United States)

    Johnson, Sandra K.; Handler, Louis M.; Briones, Janette C.

    2016-01-01

    Development of NASA's Software Defined Radio architecture, the Space Telecommunication Radio System (STRS), was initiated in 2004 with a goal of reducing the cost, risk and schedule when implementing Software Defined Radios (SDR) for National Aeronautics and Space Administration (NASA) space missions. Since STRS was first flown in 2012 on three Software Defined Radios on the Space Communication and Navigation (SCaN) Testbed, only minor changes have been made to the architecture. Multiple entities have since implemented the architecture and provided significant feedback for consideration for the next revision of the standard. The focus for the first set of updates to the architecture is items that enhance application portability. Items that require modifications to existing applications before migrating to the updated architecture will only be considered if there is compelling reasons to make the change. The significant suggestions that were further evaluated for consideration include expanding and clarifying the timing Application Programming Interfaces (APIs), improving handle name and identification (ID) definitions and use, and multiple items related to implementation of STRS Devices. In addition to ideas suggested while implementing STRS, SDR technology has evolved significantly and this impact to the architecture needs to be considered. These include incorporating cognitive concepts - learning from past decisions and making new decisions that the radio can act upon. SDRs are also being developed that do not contain a General Purpose Module - which is currently required for the platform to be STRS compliant. The purpose of this paper is to discuss the comments received, provide a summary of the evaluation considerations, and examine planned dispositions.

  12. Novel cemented cup-holding technique while performing total hip arthroplasty with navigation system

    OpenAIRE

    Hirokazu Takai, MD; Tomoki Takahashi, MD, PhD

    2017-01-01

    Recently, navigation systems have been more widely utilized in total hip arthroplasty. However, almost all of these systems have been developed for cementless cups. In the case of cemented total hip arthroplasty using a navigation system, a special-ordered cemented holder is needed. We propose a novel cemented cup-holding technique for navigation systems using readily available articles. We combine a cementless cup holder with an inverted cementless trial cup. The resulting apparatus is used ...

  13. Location-based resource allocation for OFDMA cognitive radio systems

    KAUST Repository

    Nam, Haewoon

    2010-01-01

    In cognitive radio systems, in order for the secondary users to opportunistically share the spectrum without interfering the primary users, an accurate spectrum measurement and a precise estimation of the interference at the primary users are necessary but are challenging tasks. Since it is impractical in cognitive radio systems to assume that the channel state information of the interference link is available at the cognitive transmitter, the interference at the primary users is hard to be estimated accurately. This paper introduces a resource allocation algorithm for OFDMA-based cognitive radio systems, which utilizes location information of the primary and secondary users instead of the channel state information of the interference link. Simulation results show that it is indeed effective to incorporate location information into resource allocation so that a near-optimal capacity is achieved.

  14. Inertial Pocket Navigation System: Unaided 3D Positioning

    Directory of Open Access Journals (Sweden)

    Estefania Munoz Diaz

    2015-04-01

    Full Text Available Inertial navigation systems use dead-reckoning to estimate the pedestrian’s position. There are two types of pedestrian dead-reckoning, the strapdown algorithm and the step-and-heading approach. Unlike the strapdown algorithm, which consists of the double integration of the three orthogonal accelerometer readings, the step-and-heading approach lacks the vertical displacement estimation. We propose the first step-and-heading approach based on unaided inertial data solving 3D positioning. We present a step detector for steps up and down and a novel vertical displacement estimator. Our navigation system uses the sensor introduced in the front pocket of the trousers, a likely location of a smartphone. The proposed algorithms are based on the opening angle of the leg or pitch angle. We analyzed our step detector and compared it with the state-of-the-art, as well as our already proposed step length estimator. Lastly, we assessed our vertical displacement estimator in a real-world scenario. We found that our algorithms outperform the literature step and heading algorithms and solve 3D positioning using unaided inertial data. Additionally, we found that with the pitch angle, five activities are distinguishable: standing, sitting, walking, walking up stairs and walking down stairs. This information complements the pedestrian location and is of interest for applications, such as elderly care.

  15. Inertial Pocket Navigation System: Unaided 3D Positioning

    Science.gov (United States)

    Munoz Diaz, Estefania

    2015-01-01

    Inertial navigation systems use dead-reckoning to estimate the pedestrian's position. There are two types of pedestrian dead-reckoning, the strapdown algorithm and the step-and-heading approach. Unlike the strapdown algorithm, which consists of the double integration of the three orthogonal accelerometer readings, the step-and-heading approach lacks the vertical displacement estimation. We propose the first step-and-heading approach based on unaided inertial data solving 3D positioning. We present a step detector for steps up and down and a novel vertical displacement estimator. Our navigation system uses the sensor introduced in the front pocket of the trousers, a likely location of a smartphone. The proposed algorithms are based on the opening angle of the leg or pitch angle. We analyzed our step detector and compared it with the state-of-the-art, as well as our already proposed step length estimator. Lastly, we assessed our vertical displacement estimator in a real-world scenario. We found that our algorithms outperform the literature step and heading algorithms and solve 3D positioning using unaided inertial data. Additionally, we found that with the pitch angle, five activities are distinguishable: standing, sitting, walking, walking up stairs and walking down stairs. This information complements the pedestrian location and is of interest for applications, such as elderly care. PMID:25897501

  16. 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.

  17. Novel cemented cup-holding technique while performing total hip arthroplasty with navigation system.

    Science.gov (United States)

    Takai, Hirokazu; Takahashi, Tomoki

    2017-09-01

    Recently, navigation systems have been more widely utilized in total hip arthroplasty. However, almost all of these systems have been developed for cementless cups. In the case of cemented total hip arthroplasty using a navigation system, a special-ordered cemented holder is needed. We propose a novel cemented cup-holding technique for navigation systems using readily available articles. We combine a cementless cup holder with an inverted cementless trial cup. The resulting apparatus is used as a cemented cup holder. The upside-down cup-holding technique is useful and permits cemented cup users to utilize a navigation system for placement of the acetabular component.

  18. Novel cemented cup-holding technique while performing total hip arthroplasty with navigation system

    Directory of Open Access Journals (Sweden)

    Hirokazu Takai, MD

    2017-09-01

    Full Text Available Recently, navigation systems have been more widely utilized in total hip arthroplasty. However, almost all of these systems have been developed for cementless cups. In the case of cemented total hip arthroplasty using a navigation system, a special-ordered cemented holder is needed. We propose a novel cemented cup-holding technique for navigation systems using readily available articles. We combine a cementless cup holder with an inverted cementless trial cup. The resulting apparatus is used as a cemented cup holder. The upside-down cup-holding technique is useful and permits cemented cup users to utilize a navigation system for placement of the acetabular component.

  19. An Environmental Scan of Health and Social System Navigation Services in an Urban Canadian Community

    Directory of Open Access Journals (Sweden)

    Nancy Carter RN, PhD

    2017-01-01

    Full Text Available Systems navigation services provided by a designated provider or team have the potential to address health and social disparities. We conducted an environmental scan of navigation activities in a large urban Canadian community to identify and describe: service providers who engage in systems navigation; the clients who require systems navigation support and the issues they face; activities involved; and barriers and facilitators in providing systems navigation support to clients. Using an online survey and convenience sampling, we recruited individuals who self-identified as community navigators or practiced systems navigation activities as part of their role. The majority of respondents ( n  = 145 were social workers, social services workers, or nurses. Clients of navigators struggled with mental health or addictions issues, disabilities, chronic diseases, and history of trauma or abuse. The most frequently reported activities of navigators were building professional relationships, managing paperwork, and communicating with relevant agencies or organizations. Barriers to navigation were time available in the work day, difficulty partnering due to bureaucratic structures, differing philosophies and ways of working, and a lack of central information repository in the community. Facilitators were a client-centered organization, the availability of multiple community resources in the region, and organizational support. Participants struggled with client waitlists, system issues such as lack of resources and interagency collaboration, and role clarity.

  20. A new image navigation system for MR-guided cryosurgery

    International Nuclear Information System (INIS)

    Mogami, Takuji; Dohi, Michiko; Harada, Junta

    2002-01-01

    The purpose of this study was to evaluate the feasibility of Interactive Scan Control (ISC), a new MR image navigation system, during percutaneous puncture in cryosurgery. With the ISC system in place, percutaneous MR-guided cryosurgery was performed in 26 cases, with the ISC system being used in 11 cases (five renal tumors, three uterine fibroids and three metastatic liver tumors). The ISC system comprised infrared cameras and an MR-compatible optical tracking tool that was directly connected to a cryoprobe. Tumor sizes ranged from 1.2 cm (metastatic liver tumor) to 9.0 cm (uterine fibroid), for a mean size of 3.9 cm. With ISC, one to three cryoprobes with a diameter of 2 mm or 3 mm were advanced into the tumors with the guidance of an MR fluoroscopic image. Two freeze-thaw cycles were used for cryosurgery. During the cryosurgery, the formation of iceballs was monitored on MR images. Follow-up dynamic CT or MRI as well as physical examinations were conducted after two weeks and six weeks. Placement of probes was successfully performed under the control of the ISC system. During cryosurgery, engulfment of the tumors by iceballs was carefully monitored by MRI. Necrosis of the cryoablated area was confirmed in all renal tumors by follow-up dynamic CT. The size regression of the uterine fibroids was observed through follow-up MRI. Two of the three cases of metastatic liver tumor were ablated completely. Additional therapy for a residual tumor was performed on one patient with a metastatic liver tumor. A small amount of pneumothorax was the only complication found in a patient with a metastatic liver tumor. MR-guided cryosurgery with this new navigation system was feasible with low morbidity and allowed for safe and accurate puncture with a cryoprobe. (author)

  1. Exploitation of Semantic Building Model in Indoor Navigation Systems

    Science.gov (United States)

    Anjomshoaa, A.; Shayeganfar, F.; Tjoa, A. Min

    2009-04-01

    There are many types of indoor and outdoor navigation tools and methodologies available. A majority of these solutions are based on Global Positioning Systems (GPS) and instant video and image processing. These approaches are ideal for open world environments where very few information about the target location is available, but for large scale building environments such as hospitals, governmental offices, etc the end-user will need more detailed information about the surrounding context which is especially important in case of people with special needs. This paper presents a smart indoor navigation solution that is based on Semantic Web technologies and Building Information Model (BIM). The proposed solution is also aligned with Google Android's concepts to enlighten the realization of results. Keywords: IAI IFCXML, Building Information Model, Indoor Navigation, Semantic Web, Google Android, People with Special Needs 1 Introduction Built environment is a central factor in our daily life and a big portion of human life is spent inside buildings. Traditionally the buildings are documented using building maps and plans by utilization of IT tools such as computer-aided design (CAD) applications. Documenting the maps in an electronic way is already pervasive but CAD drawings do not suffice the requirements regarding effective building models that can be shared with other building-related applications such as indoor navigation systems. The navigation in built environment is not a new issue, however with the advances in emerging technologies like GPS, mobile and networked environments, and Semantic Web new solutions have been suggested to enrich the traditional building maps and convert them to smart information resources that can be reused in other applications and improve the interpretability with building inhabitants and building visitors. Other important issues that should be addressed in building navigation scenarios are location tagging and end-user communication

  2. 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.)

  3. 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

  4. Navigation of Pedicle Screws in the Thoracic Spine with a New Electromagnetic Navigation System: A Human Cadaver Study

    Directory of Open Access Journals (Sweden)

    Patrick Hahn

    2015-01-01

    Full Text Available Introduction. Posterior stabilization of the spine is a standard procedure in spinal surgery. In addition to the standard techniques, several new techniques have been developed. The objective of this cadaveric study was to examine the accuracy of a new electromagnetic navigation system for instrumentation of pedicle screws in the spine. Material and Method. Forty-eight pedicle screws were inserted in the thoracic spine of human cadavers using EMF navigation and instruments developed especially for electromagnetic navigation. The screw position was assessed postoperatively by a CT scan. Results. The screws were classified into 3 groups: grade 1 = ideal position; grade 2 = cortical penetration <2 mm; grade 3 = cortical penetration ≥2 mm. The initial evaluation of the system showed satisfied positioning for the thoracic spine; 37 of 48 screws (77.1%, 95% confidence interval [62.7%, 88%] were classified as group 1 or 2. Discussion. The screw placement was satisfactory. The initial results show that there is room for improvement with some changes needed. The ease of use and short setup times should be pointed out. Instrumentation is achieved without restricting the operator’s mobility during navigation. Conclusion. The results indicate a good placement technique for pedicle screws. Big advantages are the easy handling of the system.

  5. Automated endoscopic navigation and advisory system from medical image

    Science.gov (United States)

    Kwoh, Chee K.; Khan, Gul N.; Gillies, Duncan F.

    1999-05-01

    In this paper, we present a review of the research conducted by our group to design an automatic endoscope navigation and advisory system. The whole system can be viewed as a two-layer system. The first layer is at the signal level, which consists of the processing that will be performed on a series of images to extract all the identifiable features. The information is purely dependent on what can be extracted from the 'raw' images. At the signal level, the first task is performed by detecting a single dominant feature, lumen. Few methods of identifying the lumen are proposed. The first method used contour extraction. Contours are extracted by edge detection, thresholding and linking. This method required images to be divided into overlapping squares (8 by 8 or 4 by 4) where line segments are extracted by using a Hough transform. Perceptual criteria such as proximity, connectivity, similarity in orientation, contrast and edge pixel intensity, are used to group edges both strong and weak. This approach is called perceptual grouping. The second method is based on a region extraction using split and merge approach using spatial domain data. An n-level (for a 2' by 2' image) quadtree based pyramid structure is constructed to find the most homogenous large dark region, which in most cases corresponds to the lumen. The algorithm constructs the quadtree from the bottom (pixel) level upward, recursively and computes the mean and variance of image regions corresponding to quadtree nodes. On reaching the root, the largest uniform seed region, whose mean corresponds to a lumen is selected that is grown by merging with its neighboring regions. In addition to the use of two- dimensional information in the form of regions and contours, three-dimensional shape can provide additional information that will enhance the system capabilities. Shape or depth information from an image is estimated by various methods. A particular technique suitable for endoscopy is the shape from shading

  6. Saint Petersburg International Conference on Integrated Navigation Systems, (9th), Held at St. Petersburg, Russia, on 27-29 May 2002

    Science.gov (United States)

    2002-05-01

    Dmitriev P.P., Shebshaevich V.S. Network satellite navigational systems. - M.:Radio and communication. 1982. 2. Harisov V.N., Petrov A.I., Boldin V.A...standardized LS-residuals) with a membership function which takes account of \\i- , introducing a weighting factor extracted from the elements of R and...numerical values of the blunders, we extract from the redundancy matrix R the diagonal and off-diagonal elements that correspond to the respective

  7. Current use of navigation system in ACL surgery: a historical review.

    Science.gov (United States)

    Zaffagnini, S; Urrizola, F; Signorelli, C; Grassi, A; Di Sarsina, T Roberti; Lucidi, G A; Marcheggiani Muccioli, G M; Bonanzinga, T; Marcacci, M

    2016-11-01

    The present review aims to analyse the available literature regarding the use of navigation systems in ACL reconstructive surgery underling the evolution during the years. A research of indexed scientific papers was performed on PubMed and Cochrane Library database. The research was performed in December 2015 with no publication year restriction. Only English-written papers and related to the terms ACL, NAVIGATION, CAOS and CAS were considered. Two reviewers independently selected only those manuscripts that presented at least the application of navigation system for ACL reconstructive surgery. One hundred and forty-six of 394 articles were finally selected. In this analysis, it was possible to review the main uses of navigation system in ACL surgery including tunnel positioning for primary and revision surgery and kinematic assessment of knee laxity before and after different surgical procedures. In the early years, until 2006, navigation system was mainly used to improve tunnel positioning, but since the last decade, this tool has been principally used for kinematics evaluation. Increased accuracy of tunnel placement was observed using navigation surgery, especially, regarding femoral, 42 of 146 articles used navigation to guide tunnel positioning. During the following years, 82 of 146 articles have used navigation system to evaluate intraoperative knee kinematic. In particular, the importance of controlling rotatory laxity to achieve better surgical outcomes has been underlined. Several applications have been described and despite the contribution of navigation systems, its potential uses and theoretical advantages, there are still controversies about its clinical benefit. The present papers summarize the most relevant studies that have used navigation system in ACL reconstruction. In particular, the analysis identified four main applications of the navigation systems during ACL reconstructive surgery have been identified: (1) technical assistance for tunnel

  8. Methods, Systems and Apparatuses for Radio Frequency Identification

    Science.gov (United States)

    Fink, Patrick W. (Inventor); Chu, Andrew W. (Inventor); Lin, Gregory Y. (Inventor); Kennedy, Timothy F. (Inventor); Ngo, Phong H. (Inventor); Brown, Dewey T. (Inventor); Byerly, Diane (Inventor)

    2017-01-01

    A system for radio frequency identification (RFID) includes an enclosure defining an interior region interior to the enclosure, and a feed for generating an electromagnetic field in the interior region in response to a signal received from an RFID reader via a radio frequency (RF) transmission line and, in response to the electromagnetic field, receiving a signal from an RFID sensor attached to an item in the interior region. The structure of the enclosure may be conductive and may include a metamaterial portion, an electromagnetically absorbing portion, or a wall extending in the interior region. Related apparatuses and methods for performing RFID are provided.

  9. Satellite Navigation Systems: Policy, Commercial and Technical Interaction.

    Science.gov (United States)

    Rycroft, M.

    2003-12-01

    This book adopts a broad perspective on positioning and navigation systems which rely on Earth orbiting satellites for their successful operation. The first of such global systems was the US Global Positioning System (GPS), and the next the Russian GLONASS system. Now studies relating to Europe's future Galileo system are gaining momentum and other nations are planning regional augmentation systems. All such systems are discussed here, particularly relating to political, commercial, legal and technical issues. The opportunities - and also the problems - of having three similar systems in operation simultaneously are examined, and several novel applications are proposed. These range from improved vehicular transport by land, sea and air, to more accurate surveying, more efficient agricultural practices and safer operations in mountainous regions. Everyone who is challenged by these topics will find this volume invaluable. ISU WWW Server; http://www.isunet.edu. Further information on ISU Symposia may also be obtained by e-mail from symposium@isu.isunet.edu Link: http://www.wkap.nl/prod/b/1-4020-1678-6

  10. A personal tourism navigation system to support traveling multiple destinations with time restrictions

    OpenAIRE

    Maruyama, Atsushi; Shibata, Naoki; Murata, Yoshihiro; Yasumoto, Keiichi; Ito, Minoru

    2004-01-01

    We propose a personal navigation system (called PNS) which navigates a tourist through multiple destinations efficiently. In our PNS, a tourist can specify multiple destinations with desired arrival/stay time and preference degree. The system calculates the route including part of the destinations satisfying tourist's requirements and navigates him/her. For the above route search problem, we have developed an efficient route search algorithm using a genetic algorithm. We have designed and imp...

  11. Positioning navigation and timing service applications in cyber physical systems

    Science.gov (United States)

    Qu, Yi; Wu, Xiaojing; Zeng, Lingchuan

    2017-10-01

    The positioning navigation and timing (PNT) architecture was discussed in detail, whose history, evolvement, current status and future plan were presented, main technologies were listed, advantages and limitations of most technologies were compared, novel approaches were introduced, and future capacities were sketched. The concept of cyber-physical system (CPS) was described and their primary features were interpreted. Then the three-layer architecture of CPS was illustrated. Next CPS requirements on PNT services were analyzed, including requirements on position reference and time reference, requirements on temporal-spatial error monitor, requirements on dynamic services, real-time services, autonomous services, security services and standard services. Finally challenges faced by PNT applications in CPS were concluded. The conclusion was expected to facilitate PNT applications in CPS, and furthermore to provide references to the design and implementation of both architectures.

  12. Flexible Multi-Numerology Systems for 5G New Radio

    OpenAIRE

    Yazar, Ahmet; Peköz, Berker; Arslan, Hüseyin

    2018-01-01

    The physical layer of 5G cellular communications systems is designed to achieve better flexibility in an effort to support diverse services and user requirements. OFDM waveform parameters are enriched with flexible multi-numerology structures. This paper describes the differences between Long Term Evolution (LTE) systems and new radio (NR) from the flexibility perspective. Research opportunities for multi-numerology systems are presented in a structured manner. Finally, inter-numerology inter...

  13. NSLS-II Radio Frequency Systems

    Energy Technology Data Exchange (ETDEWEB)

    Rose J.; Gao F.; Goel, A.; Holub, B.; Kulpin, J.; Marques, C.; Yeddulla, M.

    2015-05-03

    The National Synchrotron Light Source II is a 3 GeV X-ray user facility commissioned in 2014. The NSLS-II RF system consists of the master oscillator, digital low level RF controllers, linac, booster and storage ring RF sub-systems, as well as a supporting cryogenic system. Here we will report on RF commissioning and early operation experience of the system.

  14. Initial Assessment of Cyclone Global Navigation Satellite System (CYGNSS) Observations

    Science.gov (United States)

    McKague, D. S.; Ruf, C. S.

    2017-12-01

    The NASA Cyclone Global Navigation Satellite System (CYNSS) mission provides high temporal resolution observations of cyclones from a constellation of eight low-Earth orbiting satellites. Using the relatively new technique of Global Navigation Satellite System reflectometry (GNSS-R), all-weather observations are possible, penetrating even deep convection within hurricane eye walls. The compact nature of the GNSS-R receivers permits the use of small satellites, which in turn enables the launch of a constellation of satellites from a single launch vehicle. Launched in December of 2016, the eight CYGNSS satellites provide 25 km resolution observations of mean square slope (surface roughness) and surface winds with a 2.8 hour median revisit time from 38 S to 38 N degrees latitude. In addition to the calibration and validation of CYGNSS sea state observations, the CYGNSS science team is assessing the ability of the mission to provide estimates of cyclone size, intensity, and integrated kinetic energy. With its all-weather ability and high temporal resolution, the CYGNSS mission will add significantly to our ability to monitor cyclone genesis and intensification and will significantly reduce uncertainties in our ability to estimate cyclone intensity, a key variable in predicting its destructive potential. Members of the CYGNSS Science Team are also assessing the assimilation of CYGNSS data into hurricane forecast models to determine the impact of the data on forecast skill, using the data to study extra-tropical cyclones, and looking at connections between tropical cyclones and global scale weather, including the global hydrologic cycle. This presentation will focus on the assessment of early on-orbit observations of cyclones with respect to these various applications.

  15. Design & Test of Radio Communication and Control System for Aquaculture

    Directory of Open Access Journals (Sweden)

    Fengrong Jia

    2013-05-01

    Full Text Available Aiming at low automation degree and backward aquatic product management of current aquaculture in China, this paper designed a set of radio communication and control system which consists of 3 parts of information collection module, control module and radio communication module. This system both realizes wireless monitoring of quality parameters of water for aquaculture and realizes wireless control of water level and dissolved oxygen value through radio communication. Test results show that data transfer is more accurate and reliable after adding customized protocol and answer signals in radio communication. The highest error and missing rate within 1000 m is 0.36, the lowest error and missing rate is 0.05 and the longest response time is 49 ms. The dissolved oxygen value detection system designed in this paper is close to the testing value of existing dissolved oxygen value transmitter DO6309. With wireless data transfer mode, it has higher practicality. The wireless control of dissolved oxygen value and water level can be controlled within the appropriate range with stable and precise control. The study results can provide intelligent aquaculture model with simple operation and precise control for enormous aquatic breeders

  16. Global Navigation Satellite Systems (GNSS: The Utmost Interdisciplinary Integrator

    Directory of Open Access Journals (Sweden)

    Bernd Eissfeller

    2015-08-01

    Full Text Available Currently four global satellite navigation systems are under modernization and development: The US American GPS III, the Russian GLONASS, the European Galileo and Chinese BeiDou systems. In the paper the interdisciplinary contributions of different scientific areas to GNSS are assessed. It is outlined that GNSS is not only a technical system but also a basic element of mobile computing high-tech market. At the same time a GNSS has the role of a force enabler in security related applications. Technology, market and security policies are interdependent and are sometimes in a relationship of tension. The goal of the paper is to describe the overall systemics of GNSS from a holistic point of view. The paper also addresses the human factor side of GNSS. The requirements on human resources in GNSS are at least two-fold: On the one hand very specialized engineers are needed; on the other hand the generalists are necessary who are able to understand the system aspects. Decision makers in institutions and industry need special knowledge in technologies, economics and political strategies. Is the current university system able to educate and prepare such generalists? Are specialized master courses for GNSS needed? Are external training courses necessary?

  17. Applications of radio frequency identification systems in the mining industry

    Energy Technology Data Exchange (ETDEWEB)

    Hind, D J [Davis Derby Ltd., Derby (United Kingdom)

    1995-07-01

    Radio Frequency Identification Systems (RFID) are one of the automatic data capture technologies taking over from bar codes and magnetic swipe cards in many applications involving automatic hands free operation in arduous environments. RFID systems are based on the use of miniature radio transponders carrying encoded electronic data that is used to uniquely identify the identity of transponders. This paper reviews the types of system available and compares the various techniques involved in the different systems. The various types of transponder are described including the latest state of the art passive read/write high performance types. A review of the history of RFID systems in the mining industry is also given in the paper. The problems involved in designing and certifying a system for use in hazardous areas are also described, with particular reference to the problems of inadvertent detonator ignition by radio systems. Applications of RFID systems in the mining industry are described in considerable detail, covering applications both on the surface and underground. 1 ref., 12 figs., 1 tab.

  18. Racetrack microtron radio-frequency system

    International Nuclear Information System (INIS)

    Tallerico, P.J.; Mitra, A.K.

    1981-01-01

    The design and construction progress of a prototype rf system to drive the Los Alamos-NBS racetrack microtron (RTM) electron accelerator is described. The rf system requires 450-kW cw at 2380 MHz from a single klystron. The output from the klystron is split three ways to drive a capture section, a preaccelerator section, and the main accelerator section. The fields in each section are phase- and amplitude-controlled to tight tolerances. Temperature control of the accelerator sections also is linked to the amplitude-control system, because the system's average power is so high

  19. Waveform Developer's Guide for the Integrated Power, Avionics, and Software (iPAS) Space Telecommunications Radio System (STRS) Radio

    Science.gov (United States)

    Shalkhauser, Mary Jo W.; Roche, Rigoberto

    2017-01-01

    The Space Telecommunications Radio System (STRS) provides a common, consistent framework for software defined radios (SDRs) to abstract the application software from the radio platform hardware. The STRS standard aims to reduce the cost and risk of using complex, configurable and reprogrammable radio systems across NASA missions. To promote the use of the STRS architecture for future NASA advanced exploration missions, NASA Glenn Research Center (GRC) developed an STRS-compliant SDR on a radio platform used by the Advance Exploration System program at the Johnson Space Center (JSC) in their Integrated Power, Avionics, and Software (iPAS) laboratory. The iPAS STRS Radio was implemented on the Reconfigurable, Intelligently-Adaptive Communication System (RIACS) platform, currently being used for radio development at JSC. The platform consists of a Xilinx(Trademark) ML605 Virtex(Trademark)-6 FPGA board, an Analog Devices FMCOMMS1-EBZ RF transceiver board, and an Embedded PC (Axiomtek(Trademark) eBox 620-110-FL) running the Ubuntu 12.4 operating system. The result of this development is a very low cost STRS compliant platform that can be used for waveform developments for multiple applications. The purpose of this document is to describe how to develop a new waveform using the RIACS platform and the Very High Speed Integrated Circuits (VHSIC) Hardware Description Language (VHDL) FPGA wrapper code and the STRS implementation on the Axiomtek processor.

  20. A Microscopic Optically Tracking Navigation System That Uses High-resolution 3D Computer Graphics.

    Science.gov (United States)

    Yoshino, Masanori; Saito, Toki; Kin, Taichi; Nakagawa, Daichi; Nakatomi, Hirofumi; Oyama, Hiroshi; Saito, Nobuhito

    2015-01-01

    Three-dimensional (3D) computer graphics (CG) are useful for preoperative planning of neurosurgical operations. However, application of 3D CG to intraoperative navigation is not widespread because existing commercial operative navigation systems do not show 3D CG in sufficient detail. We have developed a microscopic optically tracking navigation system that uses high-resolution 3D CG. This article presents the technical details of our microscopic optically tracking navigation system. Our navigation system consists of three components: the operative microscope, registration, and the image display system. An optical tracker was attached to the microscope to monitor the position and attitude of the microscope in real time; point-pair registration was used to register the operation room coordinate system, and the image coordinate system; and the image display system showed the 3D CG image in the field-of-view of the microscope. Ten neurosurgeons (seven males, two females; mean age 32.9 years) participated in an experiment to assess the accuracy of this system using a phantom model. Accuracy of our system was compared with the commercial system. The 3D CG provided by the navigation system coincided well with the operative scene under the microscope. Target registration error for our system was 2.9 ± 1.9 mm. Our navigation system provides a clear image of the operation position and the surrounding structures. Systems like this may reduce intraoperative complications.

  1. An Analysis of CONUS Based Deployment of Pseudolites for Positioning, Navigation and Timing (PNT) Systems

    Science.gov (United States)

    2015-09-17

    incorporate a master “ time - keeper ” or reference transmitter that other receiver/transmitters can synchronize with. Currently, GPS provides about 1 m...AN ANALYSIS OF CONUS BASED DEPLOYMENT OF PSEUDOLITES FOR POSITIONING, NAVIGATION AND TIMING (PNT...NAVIGATION AND TIMING (PNT) SYSTEMS THESIS Presented to the Faculty Department of Systems Engineering and Management Graduate School of

  2. Performance Improvement of Inertial Navigation System by Using Magnetometer with Vehicle Dynamic Constraints

    Directory of Open Access Journals (Sweden)

    Daehee Won

    2015-01-01

    Full Text Available A navigation algorithm is proposed to increase the inertial navigation performance of a ground vehicle using magnetic measurements and dynamic constraints. The navigation solutions are estimated based on inertial measurements such as acceleration and angular velocity measurements. To improve the inertial navigation performance, a three-axis magnetometer is used to provide the heading angle, and nonholonomic constraints (NHCs are introduced to increase the correlation between the velocity and the attitude equation. The NHCs provide a velocity feedback to the attitude, which makes the navigation solution more robust. Additionally, an acceleration-based roll and pitch estimation is applied to decrease the drift when the acceleration is within certain boundaries. The magnetometer and NHCs are combined with an extended Kalman filter. An experimental test was conducted to verify the proposed method, and a comprehensive analysis of the performance in terms of the position, velocity, and attitude showed that the navigation performance could be improved by using the magnetometer and NHCs. Moreover, the proposed method could improve the estimation performance for the position, velocity, and attitude without any additional hardware except an inertial sensor and magnetometer. Therefore, this method would be effective for ground vehicles, indoor navigation, mobile robots, vehicle navigation in urban canyons, or navigation in any global navigation satellite system-denied environment.

  3. Applications of radio frequency identification systems in underground mining

    Energy Technology Data Exchange (ETDEWEB)

    Knights, P F; Kairouz, J; Daneshmend, L K; Pathak, J [McGill University, Montreal, PQ (Canada). Canadian Centre for Automation and Robotics in Mining

    1994-12-31

    The paper describes the application of Radio Frequency Identification (RFID) systems in underground hardrock mines. The operating principles and some of the applications of RDIF systems are described. The system operates by the exchange of information between transponder tags and an antenna and controller device. The suitability of RFID systems for process control, inventory control, materials handling, control of access, security, and transportation in underground coal and hardrock mines is discussed. An ore tonnage tracking system is under development that uses RDIF transponder tags to locate vehicles in an underground mine. 6 refs., 4 figs.

  4. Augmented reality-based navigation system for wrist arthroscopy: feasibility.

    Science.gov (United States)

    Zemirline, Ahmed; Agnus, Vincent; Soler, Luc; Mathoulin, Christophe L; Obdeijn, Miryam; Liverneaux, Philippe A

    2013-11-01

    In video surgery, and more specifically in arthroscopy, one of the major problems is positioning the camera and instruments within the anatomic environment. The concept of computer-guided video surgery has already been used in ear, nose, and throat (ENT), gynecology, and even in hip arthroscopy. These systems, however, rely on optical or mechanical sensors, which turn out to be restricting and cumbersome. The aim of our study was to develop and evaluate the accuracy of a navigation system based on electromagnetic sensors in video surgery. We used an electromagnetic localization device (Aurora, Northern Digital Inc., Ontario, Canada) to track the movements in space of both the camera and the instruments. We have developed a dedicated application in the Python language, using the VTK library for the graphic display and the OpenCV library for camera calibration. A prototype has been designed and evaluated for wrist arthroscopy. It allows display of the theoretical position of instruments onto the arthroscopic view with useful accuracy. The augmented reality view represents valuable assistance when surgeons want to position the arthroscope or locate their instruments. It makes the maneuver more intuitive, increases comfort, saves time, and enhances concentration.

  5. Weather-enabled future onboard surveillance and navigation systems

    Science.gov (United States)

    Mutuel, L.; Baillon, B.; Barnetche, B.; Delpy, P.

    2009-09-01

    With the increasing traffic and the development of business trajectories, there is a widespread need to anticipate any adverse weather conditions that could impact the performance of the flight or to use of atmospheric parameters to optimize trajectories. Current sensors onboard air transport are challenged to provide the required service, while new products for business jets and general aviation open the door to innovative assimilation of weather information in onboard surveillance and navigation. The paper aims at surveying current technology available to air transport aircraft and pointing out their shortcomings in view of the modernization proposed in SESAR and NextGen implementation plans. Foreseen innovations are then illustrated via results of ongoing research like FLYSAFE or standardization efforts, in particular meteorological datalink services and impact on Human-Machine Interface. The paper covers the operational need to avoid adverse weather like thunderstorm, icing, turbulence, windshear and volcanic ash, but also the requirement to control in 4D the trajectory through the integration of wind and temperature grids in the flight management. The former will lead to enhanced surveillance systems onboard the aircraft with new displays and new alerting schemes, ranging from targeted information supporting better re-planning to auto-escape strategies. The latter will be standard in next generation flight management systems. Finally both will rely on ATM products that will also assimilate weather information so that situational awareness is shared and decision is collaborative.

  6. Navigation and Positioning System Using High Altitude Platforms Systems (HAPS)

    Science.gov (United States)

    Tsujii, Toshiaki; Harigae, Masatoshi; Harada, Masashi

    Recently, some countries have begun conducting feasibility studies and R&D projects on High Altitude Platform Systems (HAPS). Japan has been investigating the use of an airship system that will function as a stratospheric platform for applications such as environmental monitoring, communications and broadcasting. If pseudolites were mounted on the airships, their GPS-like signals would be stable augmentations that would improve the accuracy, availability, and integrity of GPS-based positioning systems. Also, the sufficient number of HAPS can function as a positioning system independent of GPS. In this paper, a system design of the HAPS-based positioning system and its positioning error analyses are described.

  7. Space Telecommunications Radio System (STRS) Application Repository Design and Analysis

    Science.gov (United States)

    Handler, Louis M.

    2013-01-01

    The Space Telecommunications Radio System (STRS) Application Repository Design and Analysis document describes the STRS application repository for software-defined radio (SDR) applications intended to be compliant to the STRS Architecture Standard. The document provides information about the submission of artifacts to the STRS application repository, to provide information to the potential users of that information, and for the systems engineer to understand the requirements, concepts, and approach to the STRS application repository. The STRS application repository is intended to capture knowledge, documents, and other artifacts for each waveform application or other application outside of its project so that when the project ends, the knowledge is retained. The document describes the transmission of technology from mission to mission capturing lessons learned that are used for continuous improvement across projects and supporting NASA Procedural Requirements (NPRs) for performing software engineering projects and NASAs release process.

  8. Progress on radio frequency auxiliary heating system designs in ITER

    International Nuclear Information System (INIS)

    Makowski, M.; Bosia, G.; Elio, F.

    1996-09-01

    ITER will require over 100 MW of auxiliary power for heating, on- and off-axis current drive, accessing the H-mode, and plasma shut-down. The Electron Cyclotron Range of Frequencies (ECRF) and Ion Cyclotron Range of Frequencies (ICRF) are two forms of Radio Frequency (RF) auxiliary power being developed for these applications. Design concepts for both the ECRF and ICRF systems are presented, key features and critical design issues are discussed, and projected performances outlined

  9. UNDERSTANDING THE EVOLUTION OF CLOSE BINARY SYSTEMS WITH RADIO PULSARS

    Energy Technology Data Exchange (ETDEWEB)

    Benvenuto, O. G. [Facultad de Ciencias Astronómicas y Geofísicas, Universidad Nacional de La Plata, 1900 La Plata, Buenos Aires (Argentina); De Vito, M. A. [Instituto de Astrofísica de La Plata (IALP), CCT-CONICET-UNLP. Paseo del Bosque S/N (B1900FWA), La Plata (Argentina); Horvath, J. E., E-mail: obenvenu@fcaglp.unlp.edu.ar, E-mail: adevito@fcaglp.unlp.edu.ar, E-mail: foton@astro.iag.usp.br [Instituto de Astronomia, Geofísica e Ciências Atmosféricas, Universidade de São Paulo R. do Matão 1226 (05508-090), Cidade Universitária, São Paulo SP (Brazil)

    2014-05-01

    We calculate the evolution of close binary systems (CBSs) formed by a neutron star (behaving as a radio pulsar) and a normal donor star, which evolve either to a helium white dwarf (HeWD) or to ultra-short orbital period systems. We consider X-ray irradiation feedback and evaporation due to radio pulsar irradiation. We show that irradiation feedback leads to cyclic mass transfer episodes, allowing CBSs to be observed in between episodes as binary radio pulsars under conditions in which standard, non-irradiated models predict the occurrence of a low-mass X-ray binary. This behavior accounts for the existence of a family of eclipsing binary systems known as redbacks. We predict that redback companions should almost fill their Roche lobe, as observed in PSR J1723-2837. This state is also possible for systems evolving with larger orbital periods. Therefore, binary radio pulsars with companion star masses usually interpreted as larger than expected to produce HeWDs may also result in such quasi-Roche lobe overflow states, rather than hosting a carbon-oxygen WD. We found that CBSs with initial orbital periods of P{sub i} < 1 day evolve into redbacks. Some of them produce low-mass HeWDs, and a subgroup with shorter P{sub i} becomes black widows (BWs). Thus, BWs descend from redbacks, although not all redbacks evolve into BWs. There is mounting observational evidence favoring BW pulsars to be very massive (≳ 2 M {sub ☉}). As they should be redback descendants, redback pulsars should also be very massive, since most of the mass is transferred before this stage.

  10. Study of a new dosimetric radio-thermoluminescent systems

    International Nuclear Information System (INIS)

    Cazac, T.C.

    1980-01-01

    This is the first Romanian study to investigate conditions to obtain the radio-thermo-luminescent systems: MgB 4 O 7 :A(A-Nd,Sm,Eu,Dy,Tb,Dy+Sm and Tb+Sm) MgF 2 A (A=Mn,Dy,Tb,Sm,Li), their essential dosimetric characters, as well as the (MgF 2 =Mn) thermophosphorus mixture with a ( 6 LiF) lithium target. An investigation was developed upon a new category of radio-thermoluminescent detectors with low radiation energy dependence and fading, magnesjum boride activated by several elements of the lanthanides class (Nd,Sm,Eu,Dy,Tb). A new radio-thermoluminescent dosimetric system with high sensitivity and moderate dependence on energy radiation - (Mnsup(2+)) manganese activated magnesium fluoride - was also studied. The author explored application of investigated detectors MgF 2 =Mn, MgB 4 O 7 =Dy and MgB 4 O 7 :Tb in neutron dosimetry in complex gamma-neutron fields. It is deemed that by using the dosimetric systems reported in the thesis in order to measure gamma, beta and neutron radiation doses, dosimetric control can be ensured both in professional dosimetry and in nuclear accident dosimetry, as well as in various basic and applicative investigations. A modest contribution is thus made towards achieving the national nuclear program through an extension of the thermophosphorus range with practical applications in nuclear radiation dosimetry. (author)

  11. Evaluating a cost-effective GPS system for on-mine navigation.

    African Journals Online (AJOL)

    Benefits from this system may be applied in underground navigation and guiding rescue services .... Lightbody and Chisholm, autonomous systems can provide accuracy up to 5metres. The ..... Westminister, Colorado: Trimble Marine Division.

  12. Global Navigation Satellite System (GNSS) Rapid Clock Product Summary from NASA CDDIS

    Data.gov (United States)

    National Aeronautics and Space Administration — This derived product set consists of Global Navigation Satellite System Rapid Clock Product Summary from the NASA Crustal Dynamics Data Information System (CDDIS)....

  13. A real-time GNSS-R system based on software-defined radio and graphics processing units

    Science.gov (United States)

    Hobiger, Thomas; Amagai, Jun; Aida, Masanori; Narita, Hideki

    2012-04-01

    Reflected signals of the Global Navigation Satellite System (GNSS) from the sea or land surface can be utilized to deduce and monitor physical and geophysical parameters of the reflecting area. Unlike most other remote sensing techniques, GNSS-Reflectometry (GNSS-R) operates as a passive radar that takes advantage from the increasing number of navigation satellites that broadcast their L-band signals. Thereby, most of the GNSS-R receiver architectures are based on dedicated hardware solutions. Software-defined radio (SDR) technology has advanced in the recent years and enabled signal processing in real-time, which makes it an ideal candidate for the realization of a flexible GNSS-R system. Additionally, modern commodity graphic cards, which offer massive parallel computing performances, allow to handle the whole signal processing chain without interfering with the PC's CPU. Thus, this paper describes a GNSS-R system which has been developed on the principles of software-defined radio supported by General Purpose Graphics Processing Units (GPGPUs), and presents results from initial field tests which confirm the anticipated capability of the system.

  14. Programmable Ultra-Lightweight System Adaptable Radio Satellite Base Station

    Science.gov (United States)

    Varnavas, Kosta; Sims, Herb

    2015-01-01

    With the explosion of the CubeSat, small sat, and nanosat markets, the need for a robust, highly capable, yet affordable satellite base station, capable of telemetry capture and relay, is significant. The Programmable Ultra-Lightweight System Adaptable Radio (PULSAR) is NASA Marshall Space Flight Center's (MSFC's) software-defined digital radio, developed with previous Technology Investment Programs and Technology Transfer Office resources. The current PULSAR will have achieved a Technology Readiness Level-6 by the end of FY 2014. The extensibility of the PULSAR will allow it to be adapted to perform the tasks of a mobile base station capable of commanding, receiving, and processing satellite, rover, or planetary probe data streams with an appropriate antenna.

  15. Research on the automatic laser navigation system of the tunnel boring machine

    Science.gov (United States)

    Liu, Yake; Li, Yueqiang

    2011-12-01

    By establishing relevant coordinates of the Automatic Laser Navigation System, the basic principle of the system which accesses the TBM three-dimensional reference point and yawing angle by mathematical transformation between TBM, target prism and earth coordinate systems is discussed deeply in details. According to the way of rigid body descriptions of its posture, TBM attitude parameters measurement and data acquisition methods are proposed, and measures to improve the accuracy of the Laser Navigation System are summarized.

  16. 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.

  17. Hidden Markov Model-based Pedestrian Navigation System using MEMS Inertial Sensors

    Directory of Open Access Journals (Sweden)

    Zhang Yingjun

    2015-02-01

    Full Text Available In this paper, a foot-mounted pedestrian navigation system using MEMS inertial sensors is implemented, where the zero-velocity detection is abstracted into a hidden Markov model with 4 states and 15 observations. Moreover, an observations extraction algorithm has been developed to extract observations from sensor outputs; sample sets are used to train and optimize the model parameters by the Baum-Welch algorithm. Finally, a navigation system is developed, and the performance of the pedestrian navigation system is evaluated using indoor and outdoor field tests, and the results show that position error is less than 3% of total distance travelled.

  18. The Radio Frequency Health Node Wireless Sensor System

    Science.gov (United States)

    Valencia, J. Emilio; Stanley, Priscilla C.; Mackey, Paul J.

    2009-01-01

    The Radio Frequency Health Node (RFHN) wireless sensor system differs from other wireless sensor systems in ways originally intended to enhance utility as an instrumentation system for a spacecraft. The RFHN can also be adapted to use in terrestrial applications in which there are requirements for operational flexibility and integrability into higher-level instrumentation and data acquisition systems. As shown in the figure, the heart of the system is the RFHN, which is a unit that passes commands and data between (1) one or more commercially available wireless sensor units (optionally, also including wired sensor units) and (2) command and data interfaces with a local control computer that may be part of the spacecraft or other engineering system in which the wireless sensor system is installed. In turn, the local control computer can be in radio or wire communication with a remote control computer that may be part of a higher-level system. The remote control computer, acting via the local control computer and the RFHN, cannot only monitor readout data from the sensor units but can also remotely configure (program or reprogram) the RFHN and the sensor units during operation. In a spacecraft application, the RFHN and the sensor units can also be configured more nearly directly, prior to launch, via a serial interface that includes an umbilical cable between the spacecraft and ground support equipment. In either case, the RFHN wireless sensor system has the flexibility to be configured, as required, with different numbers and types of sensors for different applications. The RFHN can be used to effect realtime transfer of data from, and commands to, the wireless sensor units. It can also store data for later retrieval by an external computer. The RFHN communicates with the wireless sensor units via a radio transceiver module. The modular design of the RFHN makes it possible to add radio transceiver modules as needed to accommodate additional sets of wireless sensor

  19. Radio frequency system of the RIKEN ring cyclotron

    International Nuclear Information System (INIS)

    Fujisawa, T.; Ogiwara, K.; Kohara, S.; Oikawa, Y.; Yokoyama, I.; Nagase, M.; Takeshita, I.; Chiba, Y.; Kumata, Y.

    1987-01-01

    The radio-frequency(RF) system of the RIKEN ring cyclotron(K = 540) is required to work in a frequency range of 20 to 45 MHz and to generate the maximum acceleration voltage 250 kV. A new movable box type variable frequency resonator was designed for that purpose. The final amplifier is capable to deliver 300 kW. The resonators and the amplifiers have been installed at RIKEN and the performances are studied. The result shows the movable box type resonator and the power amplifier system satisfy the design aim. (author)

  20. Error Analysis and Calibration Method of a Multiple Field-of-View Navigation System

    OpenAIRE

    Shi, Shuai; Zhao, Kaichun; You, Zheng; Ouyang, Chenguang; Cao, Yongkui; Wang, Zhenzhou

    2017-01-01

    The Multiple Field-of-view Navigation System (MFNS) is a spacecraft subsystem built to realize the autonomous navigation of the Spacecraft Inside Tiangong Space Station. This paper introduces the basics of the MFNS, including its architecture, mathematical model and analysis, and numerical simulation of system errors. According to the performance requirement of the MFNS, the calibration of both intrinsic and extrinsic parameters of the system is assumed to be essential and pivotal. Hence, a n...

  1. LiDAR Scan Matching Aided Inertial Navigation System in GNSS-Denied Environments

    OpenAIRE

    Tang, Jian; Chen, Yuwei; Niu, Xiaoji; Wang, Li; Chen, Liang; Liu, Jingbin; Shi, Chuang; Hyyppä, Juha

    2015-01-01

    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. Th...

  2. 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...

  3. Navigating towards Decoupled Aquaponic Systems: A System Dynamics Design Approach

    Directory of Open Access Journals (Sweden)

    Simon Goddek

    2016-07-01

    Full Text Available The classical working principle of aquaponics is to provide nutrient-rich aquacultural water to a hydroponic plant culture unit, which in turn depurates the water that is returned to the aquaculture tanks. A known drawback is that a compromise away from optimal growing conditions for plants and fish must be achieved to produce both crops and fish in the same environmental conditions. The objective of this study was to develop a theoretical concept of a decoupled aquaponic system (DAPS, and predict water, nutrient (N and P, fish, sludge, and plant levels. This has been approached by developing a dynamic aquaponic system model, using inputs from data found in literature covering the fields of aquaculture, hydroponics, and sludge treatment. The outputs from the model showed the dependency of aquacultural water quality on the hydroponic evapotranspiration rate. This result can be explained by the fact that DAPS is based on one-way flows. These one-way flows results in accumulations of remineralized nutrients in the hydroponic component ensuring optimal conditions for the plants. The study also suggests to size the cultivation area based on P availability in the hydroponic component as P is an exhaustible resource and has been identified one of the main limiting factors for plant growth.

  4. Development and Flight Test of a Robust Optical-Inertial Navigation System Using Low-Cost Sensors

    National Research Council Canada - National Science Library

    Nielsen, Michael B

    2008-01-01

    .... This algorithm provides an alternative to the Global Positioning System (GPS) as a precision navigation source, enabling navigation in GPS denied environments, using low-cost sensors and equipment...

  5. A human motion model based on maps for navigation systems

    Directory of Open Access Journals (Sweden)

    Kaiser Susanna

    2011-01-01

    Full Text Available Abstract Foot-mounted indoor positioning systems work remarkably well when using additionally the knowledge of floor-plans in the localization algorithm. Walls and other structures naturally restrict the motion of pedestrians. No pedestrian can walk through walls or jump from one floor to another when considering a building with different floor-levels. By incorporating known floor-plans in sequential Bayesian estimation processes such as particle filters (PFs, long-term error stability can be achieved as long as the map is sufficiently accurate and the environment sufficiently constraints pedestrians' motion. In this article, a new motion model based on maps and floor-plans is introduced that is capable of weighting the possible headings of the pedestrian as a function of the local environment. The motion model is derived from a diffusion algorithm that makes use of the principle of a source effusing gas and is used in the weighting step of a PF implementation. The diffusion algorithm is capable of including floor-plans as well as maps with areas of different degrees of accessibility. The motion model more effectively represents the probability density function of possible headings that are restricted by maps and floor-plans than a simple binary weighting of particles (i.e., eliminating those that crossed walls and keeping the rest. We will show that the motion model will help for obtaining better performance in critical navigation scenarios where two or more modes may be competing for some of the time (multi-modal scenarios.

  6. 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.

  7. Aircraft Command Control Communications and Navigation Systems, AFSC 2A4X3, OSSN: 2308

    National Research Council Canada - National Science Library

    1998-01-01

    1. Survey Coverage: The Aircraft Command Control Communications and Navigation Systems career ladder was surveyed to provide current job and task data for use in updating career ladder documents and training programs...

  8. Demonstration of a Moving-Map System for Improved Lane Navigation of Amphibious Vehicles

    National Research Council Canada - National Science Library

    Clohrenz, Maura

    2003-01-01

    The Naval Research Laboratory (NRL) is testing and demonstrating a prototype moving-map system on amphibious vehicles and landing craft to aid the location neutralization and navigation around mines and obstacles in the surf and beach zone...

  9. Spatial environmental analysis on the effects of a new navigation system for freight transport

    NARCIS (Netherlands)

    Feng, T.; Arentze, T.A.; Timmermans, H.J.P.

    2012-01-01

    Considerable attention has been paid to traffic pollution modeling for commercial vehicles due to their high amount of nitrogen compounds, particulate matter and greenhouse gas emissions. Conventional navigation systems for passenger cars enable the route choice process. However, commercial route

  10. Improved Line Tracking System for Autonomous Navigation of High-Speed Vehicle

    Directory of Open Access Journals (Sweden)

    Yahya Zare Khafri

    2012-07-01

    Full Text Available Line tracking navigation is one of the most widely techniques used in the robot navigation. In this paper, a customized line tracking system is proposed for autonomous navigation of high speed vehicles. In the presented system, auxiliary information -in addition to the road path- is added to the tracking lines such as locations of turn and intersections in the real roads. Moreover, the geometric position of line sensors is re-designed enables the high rate sensing with higher reliability. Finally, a light-weight navigation algorithm is proposed allow the high-speed movement using a reasonable processing power. This system is implemented on a MIPS-based embedded processor and experimental results with this embedded system show more than 98% accuracy at 200km/h with a 1GHz processor is viable.

  11. 76 FR 22726 - Certain Multimedia Display and Navigation Devices and Systems, Components Thereof, and Products...

    Science.gov (United States)

    2011-04-22

    ... INTERNATIONAL TRADE COMMISSION [Investigation No. 337-TA-694] Certain Multimedia Display and Navigation Devices and Systems, Components Thereof, and Products Containing Same; Notice of Commission... importation, and the sale within the United States after importation of certain multimedia display and...

  12. DESIGN OF ROBUST NAVIGATION AND STABILIZATION LOOPS OF PRECISION ATTITUDE AND HEADING REFERENCE SYSTEM

    Directory of Open Access Journals (Sweden)

    Olha Sushchenko

    2017-11-01

    Full Text Available Purpose: The paper focuses on problems of design of robust precision attitude and heading reference systems, which can be applied in navigation of marine vehicles. The main goal is to create the optimization procedures for design of navigation and stabilization loops of the multimode gimballed system. The optimization procedure of the navigation loop design is based on the parametric robust H2/H∞-optimization. The optimization procedure of the stabilization loop design is based on the robust structural H∞-synthesis. Methods: To solve the given problem the methods of the robust control system theory and optimization methods are used. Results: The kinematical scheme of the precision gimballed attitude and heading reference system is represented. The parametrical optimization algorithm taking into consideration features of the researched system is given. Method of the mixed sensitivity relative to the researched system design is analyzed. Coefficients of the control laws of navigation loops are obtained based on optimization procedure providing compromise between accuracy and robustness. The robust controller of the stabilization loop was developed based on robust structural synthesis using method of the mixed sensitivity. Simulation of navigation and stabilization processes is carried out. Conclusions: The represented results prove efficiency of the proposed procedures, which can be useful for design of precision navigation systems of the moving vehicles.

  13. 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

  14. THERMAL PROTECTION AND THERMAL STABILIZATION OF FIBER-OPTICAL GYROSCOPE INCLUDED IN STRAPDOWN INERTIAL NAVIGATION SYSTEM

    Directory of Open Access Journals (Sweden)

    D. S. Gromov

    2014-03-01

    Full Text Available It is known, that temperature perturbations and thermal modes have significant influence on the accuracy of a fiber-optical gyroscope. Nowadays, thermal perturbations are among the main problems in the field of navigation accuracy. Review of existing methods for decrease of temperature influences on the accuracy of a strapdown inertial navigation system with fiberoptical gyros showed, that the usage of constructive and compensation methods only is insufficient and, therefore, thermostabilization is required. Reversible thermostabilization system is offered, its main executive elements are thermoelectric modules (Peltier’s modules, heat transfer from which is provided by heatsinks at work surfaces of modules. This variant of thermostabilization maintenance is considered; Peltier’s modules and temperature sensors for the system are chosen. Parameters of heatsinks for heat transfer intensification are calculated. Fans for necessary air circulation in the device are chosen and thickness of thermal isolation is calculated. Calculations of thermal modes of navigation system with thermostabilization are made in modern software Autodesk Simulation CFD. Comparison of results for present and previous researches and calculations shows essential decrease in gradients of temperature on gyro surfaces and better uniformity of temperature field in the whole device. Conclusions about efficiency of the given method usage in view of accuracy improvement of navigation system are made. Thermostabilization provision of a strapdown inertial navigation system with fiberoptical gyros is proved. Thermostabilization application in combination with compensational methods can reach a necessary accuracy of navigation system.

  15. A Novel Navigation Information Management System for Food Maritime Logistics Based on Internet of Things

    OpenAIRE

    Wei He; Xiumin Chu

    2014-01-01

    This study focuses on the construction of a new navigation information management system for food maritime logistics. With the vigorous development of Internet technology, the Internet of things technology has been introduced into the food maritime logistics to enhance the efficiency of food production transportation. However, the navigation information management system for food maritime logistics is still a big challenge and very limited work has been done to address safe and effective navi...

  16. BioRadioTransmitter: a self-powered wireless glucose-sensing system.

    Science.gov (United States)

    Hanashi, Takuya; Yamazaki, Tomohiko; Tsugawa, Wakako; Ikebukuro, Kazunori; Sode, Koji

    2011-09-01

    Although an enzyme fuel cell can be utilized as a glucose sensor, the output power generated is too low to power a device such as a currently available transmitter and operating system, and an external power source is required for operating an enzyme-fuel-cell-based biosensing system. We proposed a novel biosensor that we named BioCapacitor, in which a capacitor serves as a transducer. In this study, we constructed a new BioCapacitor-based system with an added radio-transmitter circuit and a miniaturized enzyme fuel cell. A miniaturized direct-electron-transfer-type compartmentless enzyme fuel cell was constructed with flavin adenine dinucleotide-dependent glucose dehydrogenase complex-based anode and a bilirubin-oxidase-based cathode. For construction of a BioRadioTransmitter wireless sensing system, a capacitor, an ultra-low-voltage charge-pump-integrated circuit, and Hartley oscillator circuit were connected to the miniaturized enzyme fuel cell. A radio-receiver circuit, comprising two field-effect transistors and a coil as an antenna, was used to amplify the signal generated from the biofuel cells. Radio wave signals generated by the BioRadioTransmitter were received, amplified, and converted from alternate to direct current by the radio receiver. When the capacitor discharges in the presence of glucose, the BioRadioTransmitter generates a radio wave, which is monitored by a radio receiver connected wirelessly to the sensing device. Magnitude of the radio wave transmission frequency change observed at the radio receiver was correlated to glucose concentration in the fuel cells. We constructed a stand-alone, self-powered, wireless glucose-sensing system called a BioRadioTransmitter by using a radio transmitter in which the radio wave transmission frequency changes with the glucose concentration in the fuel cell. The BioRadioTransmitter is a significant advance toward construction of an implantable continuous glucose monitor. © 2011 Diabetes Technology Society.

  17. Direction of Radio Finding via MUSIC (Multiple Signal Classification) Algorithm for Hardware Design System

    Science.gov (United States)

    Zhang, Zheng

    2017-10-01

    Concept of radio direction finding systems, which use radio direction finding is based on digital signal processing algorithms. Thus, the radio direction finding system becomes capable to locate and track signals by the both. Performance of radio direction finding significantly depends on effectiveness of digital signal processing algorithms. The algorithm uses the Direction of Arrival (DOA) algorithms to estimate the number of incidents plane waves on the antenna array and their angle of incidence. This manuscript investigates implementation of the DOA algorithms (MUSIC) on the uniform linear array in the presence of white noise. The experiment results exhibit that MUSIC algorithm changed well with the radio direction.

  18. A novel navigation system for maxillary positioning in orthognathic surgery: Preclinical evaluation.

    Science.gov (United States)

    Lutz, Jean-Christophe; Nicolau, Stéphane; Agnus, Vincent; Bodin, Frédéric; Wilk, Astrid; Bruant-Rodier, Catherine; Rémond, Yves; Soler, Luc

    2015-11-01

    Appropriate positioning of the maxilla is critical in orthognathic surgery. As opposed to splint-based positioning, navigation systems are versatile and appropriate in assessing the vertical dimension. Bulk and disruption to the line of sight are drawbacks of optical navigation systems. Our aim was to develop and assess a novel navigation system based on electromagnetic tracking of the maxilla, including real-time registration of head movements. Since the software interface has proved to greatly influence the accuracy of the procedure, we purposely designed and evaluated an original, user-friendly interface. A sample of 12 surgeons had to navigate the phantom osteotomized maxilla to eight given target positions using the software we have developed. Time and accuracy (translational error and angular error) were compared between a conventional and a navigated session. A questionnaire provided qualitative evaluation. Our system definitely allows a reduction in variability of time and accuracy among different operators. Accuracy was improved in all surgeons (mean terror difference = 1.11 mm, mean aerror difference = 1.32°). Operative time was decreased in trainees. Therefore, they would benefit from such a system that could also serve for educational purposes. The majority of surgeons who strongly agreed that such a navigation system would prove very helpful in complex deformities, also stated that it would be helpful in everyday orthognathic procedures. Copyright © 2015 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  19. Cooperative Cognitive Radio Systems over Nakagami-m Fading Channels

    KAUST Repository

    Hyadi, Amal

    2013-05-08

    This thesis aims to investigate the incorporation of cooperative techniques in cognitive radio networks over Nakagami-m fading channels. These last years, spectrum sharing mechanisms has gained a lot of interest in the wireless communication domain. Using cooperation in a cognitive set up make the use of spectrum much more efficient. Moreover, it helps to extend the coverage area of the cognitive network and also to reduce the transmitting power and, thus, the generated interference. In this work, we consider two particular scenarios for cooperative cognitive radio systems. The first scenario consider multihop regenerative relaying in an underlay cognitive set up. The cooperation is performed in the secondary system, in the presence of multiple primary users. Both interference power and peak power constraints are taking into account. Closed-form expressions for the statistical characteristics and multiple end- to-end performance metrics are derived. Different scenarios are presented to illustrate the obtained results and Monte Carlo simulations confirm the accuracy of our analytical derivations. In the second part of this work, we consider an overlay cognitive network with the spectrally efficient two-phase two-way relaying protocol. Two relay selection techniques, optimizing both the primary and the secondary communication, are presented. The overall outage performance is investigated and an optimal power allocation scheme, that ameliorate the outage performance of the system, is proposed. Numerical simulations are presented to illustrate and compare the obtained results.

  20. 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.

  1. 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.

  2. An Adaptive Technique for a Redundant-Sensor Navigation System. Ph.D. Thesis

    Science.gov (United States)

    Chien, T. T.

    1972-01-01

    An on-line adaptive technique is developed to provide a self-contained redundant-sensor navigation system with a capability to utilize its full potentiality in reliability and performance. The gyro navigation system is modeled as a Gauss-Markov process, with degradation modes defined as changes in characteristics specified by parameters associated with the model. The adaptive system is formulated as a multistage stochastic process: (1) a detection system, (2) an identification system and (3) a compensation system. It is shown that the sufficient statistics for the partially observable process in the detection and identification system is the posterior measure of the state of degradation, conditioned on the measurement history.

  3. The RMI Space Weather and Navigation Systems (SWANS) Project

    Science.gov (United States)

    Warnant, Rene; Lejeune, Sandrine; Wautelet, Gilles; Spits, Justine; Stegen, Koen; Stankov, Stan

    The SWANS (Space Weather and Navigation Systems) research and development project (http://swans.meteo.be) is an initiative of the Royal Meteorological Institute (RMI) under the auspices of the Belgian Solar-Terrestrial Centre of Excellence (STCE). The RMI SWANS objectives are: research on space weather and its effects on GNSS applications; permanent mon-itoring of the local/regional geomagnetic and ionospheric activity; and development/operation of relevant nowcast, forecast, and alert services to help professional GNSS/GALILEO users in mitigating space weather effects. Several SWANS developments have already been implemented and available for use. The K-LOGIC (Local Operational Geomagnetic Index K Calculation) system is a nowcast system based on a fully automated computer procedure for real-time digital magnetogram data acquisition, data screening, and calculating the local geomagnetic K index. Simultaneously, the planetary Kp index is estimated from solar wind measurements, thus adding to the service reliability and providing forecast capabilities as well. A novel hybrid empirical model, based on these ground-and space-based observations, has been implemented for nowcasting and forecasting the geomagnetic index, issuing also alerts whenever storm-level activity is indicated. A very important feature of the nowcast/forecast system is the strict control on the data input and processing, allowing for an immediate assessment of the output quality. The purpose of the LIEDR (Local Ionospheric Electron Density Reconstruction) system is to acquire and process data from simultaneous ground-based GNSS TEC and digital ionosonde measurements, and subsequently to deduce the vertical electron density distribution. A key module is the real-time estimation of the ionospheric slab thickness, offering additional infor-mation on the local ionospheric dynamics. The RTK (Real Time Kinematic) status mapping provides a quick look at the small-scale ionospheric effects on the RTK

  4. Modular Software for Spacecraft Navigation Using the Global Positioning System (GPS)

    Science.gov (United States)

    Truong, S. H.; Hartman, K. R.; Weidow, D. A.; Berry, D. L.; Oza, D. H.; Long, A. C.; Joyce, E.; Steger, W. L.

    1996-01-01

    The Goddard Space Flight Center Flight Dynamics and Mission Operations Divisions have jointly investigated the feasibility of engineering modular Global Positioning SYSTEM (GPS) navigation software to support both real time flight and ground postprocessing configurations. The goals of this effort are to define standard GPS data interfaces and to engineer standard, reusable navigation software components that can be used to build a broad range of GPS navigation support applications. The paper discusses the GPS modular software (GMOD) system and operations concepts, major requirements, candidate software architecture, feasibility assessment and recommended software interface standards. In additon, ongoing efforts to broaden the scope of the initial study and to develop modular software to support autonomous navigation using GPS are addressed,

  5. An adaptive deep-coupled GNSS/INS navigation system with hybrid pre-filter processing

    Science.gov (United States)

    Wu, Mouyan; Ding, Jicheng; Zhao, Lin; Kang, Yingyao; Luo, Zhibin

    2018-02-01

    The deep-coupling of a global navigation satellite system (GNSS) with an inertial navigation system (INS) can provide accurate and reliable navigation information. There are several kinds of deeply-coupled structures. These can be divided mainly into coherent and non-coherent pre-filter based structures, which have their own strong advantages and disadvantages, especially in accuracy and robustness. In this paper, the existing pre-filters of the deeply-coupled structures are analyzed and modified to improve them firstly. Then, an adaptive GNSS/INS deeply-coupled algorithm with hybrid pre-filters processing is proposed to combine the advantages of coherent and non-coherent structures. An adaptive hysteresis controller is designed to implement the hybrid pre-filters processing strategy. The simulation and vehicle test results show that the adaptive deeply-coupled algorithm with hybrid pre-filters processing can effectively improve navigation accuracy and robustness, especially in a GNSS-challenged environment.

  6. A 3D Model Based Imdoor Navigation System for Hubei Provincial Museum

    Science.gov (United States)

    Xu, W.; Kruminaite, M.; Onrust, B.; Liu, H.; Xiong, Q.; Zlatanova, S.

    2013-11-01

    3D models are more powerful than 2D maps for indoor navigation in a complicate space like Hubei Provincial Museum because they can provide accurate descriptions of locations of indoor objects (e.g., doors, windows, tables) and context information of these objects. In addition, the 3D model is the preferred navigation environment by the user according to the survey. Therefore a 3D model based indoor navigation system is developed for Hubei Provincial Museum to guide the visitors of museum. The system consists of three layers: application, web service and navigation, which is built to support localization, navigation and visualization functions of the system. There are three main strengths of this system: it stores all data needed in one database and processes most calculations on the webserver which make the mobile client very lightweight, the network used for navigation is extracted semi-automatically and renewable, the graphic user interface (GUI), which is based on a game engine, has high performance of visualizing 3D model on a mobile display.

  7. Communication and Jamming BDA of OFDMA Communication Systems Using the Software Defined Radio Platform WARP

    Science.gov (United States)

    2015-03-01

    COMMUNICATION AND JAMMING BDA OF OFDMA COMMUNICATION SYSTEMS USING THE SOFTWARE DEFINED RADIO PLATFORM WARP THESIS Kate J. Yaxley, FLTLT, Royal... BDA OF OFDMA COMMUNICATION SYSTEMS USING THE SOFTWARE DEFINED RADIO PLATFORM WARP THESIS Presented to the Faculty Department of Electrical and...COMMUNICATION AND JAMMING BDA OF OFDMA COMMUNICATION SYSTEMS USING THE SOFTWARE DEFINED RADIO PLATFORM WARP THESIS Kate J. Yaxley, B.E. (Elec) Hons Div II

  8. Airborne and Maritime/Fixed Station Joint Tactical Radio System (AMF JTRS)

    Science.gov (United States)

    2015-12-01

    Selected Acquisition Report (SAR) RCS: DD-A&T(Q&A)823-421 Airborne & Maritime/Fixed Station Joint Tactical Radio System (AMF JTRS) As of FY 2017...Information Program Name Airborne & Maritime/Fixed Station Joint Tactical Radio System (AMF JTRS) DoD Component Army Responsible Office References SAR...UNCLASSIFIED 5 Mission and Description Airborne & Maritime/Fixed Station Joint Tactical Radio System (AMF JTRS) products are software programmable

  9. AUTOMATIC RECOGNITION OF CORONAL TYPE II RADIO BURSTS: THE AUTOMATED RADIO BURST IDENTIFICATION SYSTEM METHOD AND FIRST OBSERVATIONS

    International Nuclear Information System (INIS)

    Lobzin, Vasili V.; Cairns, Iver H.; Robinson, Peter A.; Steward, Graham; Patterson, Garth

    2010-01-01

    Major space weather events such as solar flares and coronal mass ejections are usually accompanied by solar radio bursts, which can potentially be used for real-time space weather forecasts. Type II radio bursts are produced near the local plasma frequency and its harmonic by fast electrons accelerated by a shock wave moving through the corona and solar wind with a typical speed of ∼1000 km s -1 . The coronal bursts have dynamic spectra with frequency gradually falling with time and durations of several minutes. This Letter presents a new method developed to detect type II coronal radio bursts automatically and describes its implementation in an extended Automated Radio Burst Identification System (ARBIS 2). Preliminary tests of the method with spectra obtained in 2002 show that the performance of the current implementation is quite high, ∼80%, while the probability of false positives is reasonably low, with one false positive per 100-200 hr for high solar activity and less than one false event per 10000 hr for low solar activity periods. The first automatically detected coronal type II radio burst is also presented.

  10. Enhanced cognitive Radio Resource Management for LTE systems

    KAUST Repository

    Alqerm, Ismail

    2013-10-01

    The explosive growth in mobile Internet and related services has increased the need for more bandwidth in cellular networks. The Long-Term Evolution (LTE) technology is an attractive solution for operators and subscribers to meet such need since it provides high data rates and scalable bandwidth. Radio Resource Management (RRM) is essential for LTE to provide better communication quality and meet the application QoS requirements. Cognitive resource management is a promising solution for LTE RRM as it improves network efficiency by exploiting radio environment information, intelligent optimization algorithms to configure transmission parameters, and mitigate interference. In this paper, we propose a cognitive resource management scheme to adapt LTE network parameters to the environment conditions. The scheme optimizes resource blocks assignment, modulation selection and bandwidth selection to maximize throughput and minimize interference. The scheme uses constrained optimization for throughput maximization and interference control. It is also enhanced by learning mechanism to reduce the optimization complexity and improve the decision-making quality. Our evaluation results show that our scheme achieved significant improvements in throughput and LTE system capacity. Results also show the improvement in the user satisfaction over other techniques in LTE RRM.

  11. Applications of different design methodologies in navigation systems and development at JPL

    Science.gov (United States)

    Thurman, S. W.

    1990-01-01

    The NASA/JPL deep space navigation system consists of a complex array of measurement systems, data processing systems, and support facilities, with components located both on the ground and on-board interplanetary spacecraft. From its beginings nearly 30 years ago, this system has steadily evolved and grown to meet the demands for ever-increasing navigation accuracy placed on it by a succession of unmanned planetary missions. Principal characteristics of this system are its capabilities and great complexity. Three examples in the design and development of interplanetary space navigation systems are examined in order to make a brief assessment of the usefulness of three basic design theories, known as normative, rational, and heuristic. Evaluation of the examples indicates that a heuristic approach, coupled with rational-based mathematical and computational analysis methods, is used most often in problems such as orbit determination strategy development and mission navigation system design, while normative methods have seen only limited use is such applications as the development of large software systems and in the design of certain operational navigation subsystems.

  12. Outage performance of cognitive radio systems with Improper Gaussian signaling

    KAUST Repository

    Amin, Osama

    2015-06-14

    Improper Gaussian signaling has proved its ability to improve the achievable rate of the systems that suffer from interference compared with proper Gaussian signaling. In this paper, we first study impact of improper Gaussian signaling on the performance of the cognitive radio system by analyzing the outage probability of both the primary user (PU) and the secondary user (SU). We derive exact expression of the SU outage probability and upper and lower bounds for the PU outage probability. Then, we design the SU signal by adjusting its transmitted power and the circularity coefficient to minimize the SU outage probability while maintaining a certain PU quality-of-service. Finally, we evaluate the proposed bounds and adaptive algorithms by numerical results.

  13. 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

  14. Columbia River System Operation Review final environmental impact statement. Appendix H: Navigation

    International Nuclear Information System (INIS)

    1995-11-01

    The System Operation Review (SOR) is a study and environmental compliance process being used by the three Federal agencies to analyze future operations of the system and river use issues. The goal of the SOR is to achieve a coordinated system operation strategy for the river that better meets the needs of all river users. This technical appendix addresses only the effects of alternative system operating strategies for managing the Columbia River system. The Navigation Technical Appendix presents the analysis of the various SOR alternatives in terms of their potential affects on the congressionally authorized navigation system within the Columbia and Snake river waterways. The focus of the study, impacts to the authorized navigation, improvements/developments, reflects on one of the continuing historical missions of the US Army Corps of Engineers: to promote safe commercial navigation of the nation's waterways benefiting the development of commerce within the US. The study and evaluation process involved Scoping, Screening and Full Scale Evaluation. During screening two models were developed; one was used to evaluate the effects of the various alternatives on navigation through the Snake River Projects and the other the effects on the Dworshak Pool. Full Scale Analysis was expanded to included a study of effects throughout the system

  15. Taiwan/TriG Radio Occultation Process System (TROPS): A Brief Introduction of Atmospheric Productions

    Science.gov (United States)

    Huang, Cheng-Yung; Yeh, Wen-Hao; Tseng, Tzu-Pang; Chen, Linton J.

    2017-04-01

    Global Positioning System (GPS) Radio Occultation (RO) technique has been used to investigate the Earth's atmosphere since 1990s. In 2006, Taiwan has launched six low Earth orbit (LEO) satellites as a RO constellation mission, named FORMOSAT-3 /COSMIC (F-3/C). F-3/C mission can release 1500-2500 data sets per day for both neutral atmosphere and ionosphere. With the advent of Global Navigation Satellite System (GNSS) in ten years and FORMOSAT-7/COSMIC-2 (F-7/C-2) mission, 12 LEO satellites are planned to be launched and deployed in two clusters of 6-satellites into the designated low and high inclination orbits in 2017 and 2020(TBD), respectively. The amount of RO data set will increase to about 8000 set per day with the using of GNSS TriG (GPS, Glonass, Galileo) receivers. The first phase of FS-7 mission is designed to low inclination (24 deg) orbit to improve the ability of server weather forecasting, like typhoon and monsoon rainfall around tropical region. The second is high inclination (72 deg) for global distribution. In order to observe better water vapor profiles, the 4x3 antennas arrays will be on board to receive weak signals which pass through low troposphere around earth surface. This report will introduce the status of F-7/C-2 mission and atmospheric part of occultation data process software TROPS.

  16. 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

  17. Navigation Strategies for Primitive Solar System Body Rendezvous and Proximity Operations

    Science.gov (United States)

    Getzandanner, Kenneth M.

    2011-01-01

    A wealth of scientific knowledge regarding the composition and evolution of the solar system can be gained through reconnaissance missions to primitive solar system bodies. This paper presents analysis of a baseline navigation strategy designed to address the unique challenges of primitive body navigation. Linear covariance and Monte Carlo error analysis was performed on a baseline navigation strategy using simulated data from a· design reference mission (DRM). The objective of the DRM is to approach, rendezvous, and maintain a stable orbit about the near-Earth asteroid 4660 Nereus. The outlined navigation strategy and resulting analyses, however, are not necessarily limited to this specific target asteroid as they may he applicable to a diverse range of mission scenarios. The baseline navigation strategy included simulated data from Deep Space Network (DSN) radiometric tracking and optical image processing (OpNav). Results from the linear covariance and Monte Carlo analyses suggest the DRM navigation strategy is sufficient to approach and perform proximity operations in the vicinity of the target asteroid with meter-level accuracy.

  18. Combined Global Navigation Satellite Systems in the Space Service Volume

    Science.gov (United States)

    Force, Dale A.; Miller, James J.

    2013-01-01

    Besides providing position, velocity, and timing (PVT) for terrestrial users, the Global Positioning System (GPS) is also being used to provide PVT information for earth orbiting satellites. In 2006, F. H. Bauer, et. al., defined the Space Service Volume in the paper GPS in the Space Service Volume , presented at ION s 19th international Technical Meeting of the Satellite Division, and looked at GPS coverage for orbiting satellites. With GLONASS already operational, and the first satellites of the Galileo and Beidou/COMPASS constellations already in orbit, it is time to look at the use of the new Global Navigation Satellite Systems (GNSS) coming into service to provide PVT information for earth orbiting satellites. This presentation extends GPS in the Space Service Volume by examining the coverage capability of combinations of the new constellations with GPS GPS was first explored as a system for refining the position, velocity, and timing of other spacecraft equipped with GPS receivers in the early eighties. Because of this, a new GPS utility developed beyond the original purpose of providing position, velocity, and timing services for land, maritime, and aerial applications. GPS signals are now received and processed by spacecraft both above and below the GPS constellation, including signals that spill over the limb of the earth. Support of GPS space applications is now part of the system plan for GPS, and support of the Space Service Volume by other GNSS providers has been proposed to the UN International Committee on GNSS (ICG). GPS has been demonstrated to provide decimeter level position accuracy in real-time for satellites in low Earth orbit (centimeter level in non-real-time applications). GPS has been proven useful for satellites in geosynchronous orbit, and also for satellites in highly elliptical orbits. Depending on how many satellites are in view, one can keep time locked to the GNSS standard, and through that to Universal Time as long as at least one

  19. Establishment of high-precision navigation system in the Republic of Armenia

    Directory of Open Access Journals (Sweden)

    Manukyan Larisa Vladimirovna

    2015-04-01

    Full Text Available Medium-Earth orbit satellite systems make it possible to provide services on time coordination and navigation support for a wide range of consumers. At present, there are global navigation satellite systems GLONASS (Russia and GPS (USA. Users of these systems have an opportunity to determine their location accurately with the given characteristics of their navigation devices. In all developed countries the progress of geodesy and cartography is closely related to the implementation of advanced new technologies in both scientific and industrial areas. The introduction of new technologies and equipment in production is essential for the development of geodesy and cartography, bringing the existing geodetic networks and cartographic materials to modern condition. In the Republic of Armenia there are also plans on introduction of the systems for monitoring and management of vehicles for various purposes, as well as it is proposed to establish and implement an effective satellite navigation system to monitor and control traffic on the basis of advanced satellite technology. The article describes the basic steps to create the network of reference stations, GPS, aerial photography of much of the territory of Armenia, the creation of digital terrain model and the new maps by orthophotoplans. The analysis of the materials were carried out, on the basis of which in the Republic in 2015 a high-precision navigation system will be created. Due to the hard work of surveyors, cartographers and topographers the Republic was brought to European states level.

  20. 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.

  1. MODELING OF BEHAVIORAL ACTIVITY OF AIR NAVIGATION SYSTEM'S HUMAN-OPERATOR IN FLIGHT EMERGENCIES

    Directory of Open Access Journals (Sweden)

    Volodymyr Kharchenko

    2012-09-01

    Full Text Available  The Air Navigation System is presented as a complex socio-technical system. The influence on decision-making by Air Navigation System's human-operator of the professional factors as well as the factors of non-professional nature has been defined. Logic determined and stochastic models of decision-making by the Air Navigation System's human-operator in flight emergencies have been developed. The scenarios of developing a flight situation in case of selecting either the positive or negative pole in accordance with the reflexive theory have been obtained. The informational support system of the operator in the unusual situations on the basis of Neural Network model of evaluating the efficiency of the potential alternative of flight completion has been built.

  2. A Qualitative Approach to Mobile Robot Navigation Using RFID

    International Nuclear Information System (INIS)

    Hossain, M; Rashid, M M; Bhuiyan, M M I; Ahmed, S; Akhtaruzzaman, M

    2013-01-01

    Radio Frequency Identification (RFID) system allows automatic identification of items with RFID tags using radio-waves. As the RFID tag has its unique identification number, it is also possible to detect a specific region where the RFID tag lies in. Recently it is widely been used in mobile robot navigation, localization, and mapping both in indoor and outdoor environment. This paper represents a navigation strategy for autonomous mobile robot using passive RFID system. Conventional approaches, such as landmark or dead-reckoning with excessive number of sensors, have complexities in establishing the navigation and localization process. The proposed method satisfies less complexity in navigation strategy as well as estimation of not only the position but also the orientation of the autonomous robot. In this research, polar coordinate system is adopted on the navigation surface where RFID tags are places in a grid with constant displacements. This paper also presents the performance comparisons among various grid architectures through simulation to establish a better solution of the navigation system. In addition, some stationary obstacles are introduced in the navigation environment to satisfy the viability of the navigation process of the autonomous mobile robot

  3. Overview of Radio Resource Management (RRM) issues in multi-radio access systems

    NARCIS (Netherlands)

    Jorguseski, L.; Prasad, R.

    2004-01-01

    The concept of multi-radio access networks is currently considered as a strong candidate for the next generation wireless access networks. This concept incorporates conventional cellular networks such as GERAN or UTRAN for wide area coverage while local-area networks such as IEEE 802.11, HIPERLAN/2,

  4. A new systematic calibration method of ring laser gyroscope inertial navigation system

    Science.gov (United States)

    Wei, Guo; Gao, Chunfeng; Wang, Qi; Wang, Qun; Xiong, Zhenyu; Long, Xingwu

    2016-10-01

    Inertial navigation system has been the core component of both military and civil navigation systems. Before the INS is put into application, it is supposed to be calibrated in the laboratory in order to compensate repeatability error caused by manufacturing. Discrete calibration method cannot fulfill requirements of high-accurate calibration of the mechanically dithered ring laser gyroscope navigation system with shock absorbers. This paper has analyzed theories of error inspiration and separation in detail and presented a new systematic calibration method for ring laser gyroscope inertial navigation system. Error models and equations of calibrated Inertial Measurement Unit are given. Then proper rotation arrangement orders are depicted in order to establish the linear relationships between the change of velocity errors and calibrated parameter errors. Experiments have been set up to compare the systematic errors calculated by filtering calibration result with those obtained by discrete calibration result. The largest position error and velocity error of filtering calibration result are only 0.18 miles and 0.26m/s compared with 2 miles and 1.46m/s of discrete calibration result. These results have validated the new systematic calibration method and proved its importance for optimal design and accuracy improvement of calibration of mechanically dithered ring laser gyroscope inertial navigation system.

  5. 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

  6. Flight evaluations of approach/landing navigation sensor systems. MLS to kohokei hiko jikken. ; 1990 nendo no jikken gaiyo

    Energy Technology Data Exchange (ETDEWEB)

    1992-07-01

    Flight test results of such navigation sensor systems as MLS (microwave landing system), GPS(global positioning system) and INS (inertial navigation system) on the Dornier-228 research aircraft in 1990 were reported, which tests have being promoted by National Aerospace Laboratory (NAL), Japan to develop unmanned approach/landing (A/L) navigation sensor systems for the future spaceplane HOPE. The measured data corresponding to a WGS84 (world geodetic system 1984) navigation coordinate system were evaluated, and the reference orbit was also prepared by laser tracker analysis. The navigation sensor systems such as MLS were evaluated on the basis of CMN (control motion noise) or PFE (path following error), and preliminary calculation was also conducted for a GPS-INS hybrid system. As experimental results, several data were gathered for each sensor system resulting in possible data comparison between the sensor systems, and the feasibility of the GPS-INS hybrid system was also confirmed. 35 refs., 49 figs., 22 tabs.

  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. 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.

  9. Looking Good, Feeling Good – Tac Map: a navigation system for the blind

    OpenAIRE

    Chamberlain, Paul; Dieng, Patricia

    2011-01-01

    This paper describes the research and development of a navigation system for the blind that provides a tactile and visual language that can be understood by both sighted and blind users. It describes key work and issues in the development of graphical symbols and in particular the pioneering work of Neurath‟s ISOTYPES, as well as more specific communication systems for blind people. The paper focuses on the development of "TacMap‟, a navigation system for the blind. User engagement has been f...

  10. Error analysis for determination of accuracy of an ultrasound navigation system for head and neck surgery.

    Science.gov (United States)

    Kozak, J; Krysztoforski, K; Kroll, T; Helbig, S; Helbig, M

    2009-01-01

    The use of conventional CT- or MRI-based navigation systems for head and neck surgery is unsatisfactory due to tissue shift. Moreover, changes occurring during surgical procedures cannot be visualized. To overcome these drawbacks, we developed a novel ultrasound-guided navigation system for head and neck surgery. A comprehensive error analysis was undertaken to determine the accuracy of this new system. The evaluation of the system accuracy was essentially based on the method of error definition for well-established fiducial marker registration methods (point-pair matching) as used in, for example, CT- or MRI-based navigation. This method was modified in accordance with the specific requirements of ultrasound-guided navigation. The Fiducial Localization Error (FLE), Fiducial Registration Error (FRE) and Target Registration Error (TRE) were determined. In our navigation system, the real error (the TRE actually measured) did not exceed a volume of 1.58 mm(3) with a probability of 0.9. A mean value of 0.8 mm (standard deviation: 0.25 mm) was found for the FRE. The quality of the coordinate tracking system (Polaris localizer) could be defined with an FLE of 0.4 +/- 0.11 mm (mean +/- standard deviation). The quality of the coordinates of the crosshairs of the phantom was determined with a deviation of 0.5 mm (standard deviation: 0.07 mm). The results demonstrate that our newly developed ultrasound-guided navigation system shows only very small system deviations and therefore provides very accurate data for practical applications.

  11. 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.

  12. Performance Evaluation of Irbene RT-16 Radio Telescope Receiving System

    Directory of Open Access Journals (Sweden)

    Bleiders M.

    2017-12-01

    Full Text Available In the present paper, recent measurement results of refurbished Irbene RT-16 radio telescope receiving system performance are presented. The aim of the research is to evaluate characteristics of RT-16, which will allow carrying out necessary amplitude calibration in both single dish and VLBI observations, to improve the performance of existing system as well as to monitor, control and compare performance if possible changes in the receiving system will occur in future. The evaluated receiving system is 16 m Cassegrain antenna equipped with a cryogenic receiver with frequency range from 4.5 to 8.8 GHz, which is divided into four sub-bands. Multiple calibration sessions have been carried out by observing stable astronomical sources with known flux density by using in-house made total power registration backend. First, pointing offset calibration has been carried out and pointing model coefficients calculated and applied. Then, amplitude calibration, namely antenna sensitivity, calibration diode equivalent flux density and gain curve measurements have been carried out by observing calibration sources at different antenna elevations at each of the receiver sub-bands. Beam patterns have also been evaluated at different frequency bands. As a whole, acquired data will serve as a reference point for comparison in future performance evaluation of RT-16.

  13. Global Navigation Satellite System (GNSS) Final Clock Product (5 minute resolution, daily files, generated weekly) from NASA CDDIS

    Data.gov (United States)

    National Aeronautics and Space Administration — This derived product set consists of Global Navigation Satellite System Final Satellite and Receiver Clock Product (5-minute granularity, daily files, generated...

  14. A deterministic model for the planning of microcellular mobile radio communication systems

    NARCIS (Netherlands)

    Klaassen, M.G.J.J.; Mawira, A.

    1994-01-01

    A ray model for field strength prediction for the planning of microcellular mobile radio communication systems is presented. The software developed at Eindhoven University of Technology for LMSS has been adapted for application in microcellular mobile radio communication systems. The adaption

  15. Real-time Risk Assessment for Aids to Navigation Using Fuzzy-FSA on Three-Dimensional Simulation System

    Directory of Open Access Journals (Sweden)

    Jinbiao Chen

    2014-06-01

    Full Text Available The risk level of the Aids to Navigation (AtoNs can reflect the ship navigation safety level in the channel to some extent. In order to appreciate the risk level of the aids to navigation (AtoNs in a navigation channel and to provide some decision-making suggestions for the AtoNs Maintenance and Management Department, the risk assessment index system of the AtoNs was built considering the advanced experience of IALA. Under the Formal Safety Assessment frame, taking the advantages of the fuzzy comprehensive evaluation method, the fuzzy-FSA model of risk assessment for aids to navigation was established. The model was implemented for the assessment of aids to navigation in Shanghai area based on the aids to navigation three-dimensional simulation system. The real-time data were extracted from the existing information system of aids to navigation, and the real-time risk assessment for aids to navigation of the chosen channel was performed on platform of the three-dimensional simulation system, with the risk assessment software. Specifically, the deep-water channel of the Yangtze River estuary was taken as an example to illustrate the general assessment procedure. The method proposed presents practical significance and application prospect on the maintenance and management of the aids to navigation.

  16. Analysis of time in establishing synchronization radio communication system with expanded spectrum conditions for communication with mobile robots

    Science.gov (United States)

    Latinovic, T. S.; Kalabic, S. B.; Barz, C. R.; Petrica, P. Paul; Pop-Vădean, A.

    2018-01-01

    This paper analyzes the influence of the Doppler Effect on the length of time to establish synchronization pseudorandom sequences in radio communications systems with an expanded spectrum. Also, this paper explores the possibility of using secure wireless communication for modular robots. Wireless communication could be used for local and global communication. We analyzed a radio communication system integrator, including the two effects of the Doppler signal on the duration of establishing synchronization of the received and locally generated pseudorandom sequence. The effects of the impact of the variability of the phase were analyzed between the said sequences and correspondence of the phases of these signals with the interval of time of acquisition of received sequences. An analysis of these impacts is essential in the transmission of signal and protection of the transfer of information in the communication systems with an expanded range (telecommunications, mobile telephony, Global Navigation Satellite System GNSS, and wireless communication). Results show that wireless communication can provide a safety approach for communication with mobile robots.

  17. Designing a wearable navigation system for image-guided cancer resection surgery.

    Science.gov (United States)

    Shao, Pengfei; Ding, Houzhu; Wang, Jinkun; Liu, Peng; Ling, Qiang; Chen, Jiayu; Xu, Junbin; Zhang, Shiwu; Xu, Ronald

    2014-11-01

    A wearable surgical navigation system is developed for intraoperative imaging of surgical margin in cancer resection surgery. The system consists of an excitation light source, a monochromatic CCD camera, a host computer, and a wearable headset unit in either of the following two modes: head-mounted display (HMD) and Google glass. In the HMD mode, a CMOS camera is installed on a personal cinema system to capture the surgical scene in real-time and transmit the image to the host computer through a USB port. In the Google glass mode, a wireless connection is established between the glass and the host computer for image acquisition and data transport tasks. A software program is written in Python to call OpenCV functions for image calibration, co-registration, fusion, and display with augmented reality. The imaging performance of the surgical navigation system is characterized in a tumor simulating phantom. Image-guided surgical resection is demonstrated in an ex vivo tissue model. Surgical margins identified by the wearable navigation system are co-incident with those acquired by a standard small animal imaging system, indicating the technical feasibility for intraoperative surgical margin detection. The proposed surgical navigation system combines the sensitivity and specificity of a fluorescence imaging system and the mobility of a wearable goggle. It can be potentially used by a surgeon to identify the residual tumor foci and reduce the risk of recurrent diseases without interfering with the regular resection procedure.

  18. A self-calibration method in single-axis rotational inertial navigation system with rotating mechanism

    Science.gov (United States)

    Chen, Yuanpei; Wang, Lingcao; Li, Kui

    2017-10-01

    Rotary inertial navigation modulation mechanism can greatly improve the inertial navigation system (INS) accuracy through the rotation. Based on the single-axis rotational inertial navigation system (RINS), a self-calibration method is put forward. The whole system is applied with the rotation modulation technique so that whole inertial measurement unit (IMU) of system can rotate around the motor shaft without any external input. In the process of modulation, some important errors can be decoupled. Coupled with the initial position information and attitude information of the system as the reference, the velocity errors and attitude errors in the rotation are used as measurement to perform Kalman filtering to estimate part of important errors of the system after which the errors can be compensated into the system. The simulation results show that the method can complete the self-calibration of the single-axis RINS in 15 minutes and estimate gyro drifts of three-axis, the installation error angle of the IMU and the scale factor error of the gyro on z-axis. The calibration accuracy of optic gyro drifts could be about 0.003°/h (1σ) as well as the scale factor error could be about 1 parts per million (1σ). The errors estimate reaches the system requirements which can effectively improve the longtime navigation accuracy of the vehicle or the boat.

  19. 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...

  20. The Odd Man Out: How Fathers Navigate the Special Education System

    Science.gov (United States)

    Mueller, Tracy Gershwin; Buckley, Pamela C.

    2014-01-01

    Research about parent experiences with the special education system is largely dominated by the perspectives of mothers. Using purposeful sampling techniques, we interviewed 20 active fathers about their experiences navigating the special education system. All the fathers described three primary roles they experienced, including acting as a…

  1. Radio-wave propagation for space communications systems

    Science.gov (United States)

    Ippolito, L. J.

    1981-01-01

    The most recent information on the effects of Earth's atmosphere on space communications systems is reviewed. The design and reliable operation of satellite systems that provide the many applications in space which rely on the transmission of radio waves for communications and scientific purposes are dependent on the propagation characteristics of the transmission path. The presence of atmospheric gases, clouds, fog, precipitation, and turbulence causes uncontrolled variations in the signal characteristics. These variations can result in a reduction of the quality and reliability of the transmitted information. Models and other techniques are used in the prediction of atmospheric effects as influenced by frequency, geography, elevation angle, and type of transmission. Recent data on performance characteristics obtained from direct measurements on satellite links operating to above 30 GHz have been reviewed. Particular emphasis has been placed on the effects of precipitation on the Earth/space path, including rain attenuation, and ice particle depolarization. Other factors are sky noise, antenna gain degradation, scintillations, and bandwidth coherence. Each of the various propagation factors has an effect on design criteria for communications systems. These criteria include link reliability, power margins, noise contribution, modulation and polarization factors, channel cross talk, error rate, and bandwidth limitations.

  2. Microwave systems applications in deep space telecommunications and navigation - Space Exploration Initiative architectures

    Science.gov (United States)

    Hall, Justin R.; Hastrup, Rolf C.; Bell, David J.

    1992-06-01

    The general support requirements of a typical SEI mission set, along with the mission operations objectives and related telecommunications, navigation, and information management (TNIM) support infrastructure options are described. Responsive system architectures and designs are proposed, including a Mars orbiting communications relay satellite system and a Mars-centered navigation capability for servicing all Mars missions. With the TNIM architecture as a basis, key elements of the microwave link design are proposed. The needed new technologies which enable these designs are identified, and current maturity is assessed.

  3. 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...

  4. Vacuum pumping system for the JT-60 radio-frequency heating system

    International Nuclear Information System (INIS)

    Yokokura, Kenji; Ikeda, Yoshitaka; Imai, Tuyoshi; Suganuma, Kazuaki; Nagashima, Takashi

    1988-01-01

    The basic design requirements set up for the JT-60 radio-frequency heating system included: (1) rapid pumping of gas released upon application of a radio-frequency power to maintain the pressure in the launchers at 10 -2 - 10 -3 Pa or less, (2) incorporation of a gas analysis system that can operate under a strong field and high pressure (>10 -2 Pa) to permit remote controlled data collection and processing, and (3) low cost, multiple functions and high reliability. The vacuum pumping system, consisting of three units for low hybrid radio-frequency (LHRF) and one unit for ion cyclotron radio-frequency (ICRF), is connected to each launcher provided at the four ports of JT-60. The LHRF unit is composed of a main pump, an alumina joint for electrical insulation from the launcher, a metallic gate valve for isolation from the JT-60 vacuum region, and various vacuum gauges. Only a turbo-molecular pump is used for the ICRF system because a large-scale differential pumping is not required. A gas measuring system is incorporated which consists of a mass filter, personal computer, turbo-molecular pump, and variable flow valve equipped with an APG control. This system is designed to identify and make use of gas impurities released during the launcher aging process. The control system employed consists of a personal computer, interlock control board, data logger and other devices such as vacuum gages. (Nogami, K.)

  5. 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.

  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. Radio frequency tags systems to initiate system processing

    Science.gov (United States)

    Madsen, Harold O.; Madsen, David W.

    1994-09-01

    This paper describes the automatic identification technology which has been installed at Applied Magnetic Corp. MR fab. World class manufacturing requires technology exploitation. This system combines (1) FluoroTrac cassette and operator tracking, (2) CELLworks cell controller software tools, and (3) Auto-Soft Inc. software integration services. The combined system eliminates operator keystrokes and errors during normal processing within a semiconductor fab. The methods and benefits of this system are described.

  8. Cognitive radio networks medium access control for coexistence of wireless systems

    CERN Document Server

    Bian, Kaigui; Gao, Bo

    2014-01-01

    This book gives a comprehensive overview of the medium access control (MAC) principles in cognitive radio networks, with a specific focus on how such MAC principles enable different wireless systems to coexist in the same spectrum band and carry out spectrum sharing.  From algorithm design to the latest developments in the standards and spectrum policy, readers will benefit from leading-edge knowledge of how cognitive radio systems coexist and share spectrum resources.  Coverage includes cognitive radio rendezvous, spectrum sharing, channel allocation, coexistence in TV white space, and coexistence of heterogeneous wireless systems.   • Provides a comprehensive reference on medium access control (MAC)-related problems in the design of cognitive radio systems and networks; • Includes detailed analysis of various coexistence problems related to medium access control in cognitive radio networks; • Reveals novel techniques for addressing the challenges of coexistence protocol design at a higher level ...

  9. Joint image restoration and location in visual navigation system

    Science.gov (United States)

    Wu, Yuefeng; Sang, Nong; Lin, Wei; Shao, Yuanjie

    2018-02-01

    Image location methods are the key technologies of visual navigation, most previous image location methods simply assume the ideal inputs without taking into account the real-world degradations (e.g. low resolution and blur). In view of such degradations, the conventional image location methods first perform image restoration and then match the restored image on the reference image. However, the defective output of the image restoration can affect the result of localization, by dealing with the restoration and location separately. In this paper, we present a joint image restoration and location (JRL) method, which utilizes the sparse representation prior to handle the challenging problem of low-quality image location. The sparse representation prior states that the degraded input image, if correctly restored, will have a good sparse representation in terms of the dictionary constructed from the reference image. By iteratively solving the image restoration in pursuit of the sparest representation, our method can achieve simultaneous restoration and location. Based on such a sparse representation prior, we demonstrate that the image restoration task and the location task can benefit greatly from each other. Extensive experiments on real scene images with Gaussian blur are carried out and our joint model outperforms the conventional methods of treating the two tasks independently.

  10. A Wireless Phone Charging System using Radio Frequency Energy Harvesting

    Directory of Open Access Journals (Sweden)

    M. Abdulkadir

    2017-10-01

    Full Text Available A wireless phone charging system using Radio Frequency (RF energy harvesting is presented in this paper. Battery size and extension of charge duration offer great challenge in mobile devices and the fact that one has to always connect it to the mains for charging. The research seeks to employ the RF received by its antenna to recharge mobile end devices. This study determined the suitable frequency for power transmission and chooses an efficient microstrip patch antenna which has a gain of 3.762dB, directivity of 5.906dB, and a power density of 7.358dBW/m2. A 7stage voltage doubler was employed to harvest the 3.75V dc from the RF which is suitable to charge a mobile phone. The antenna was designed and simulated using Computer Simulation Technology (CST studio suite while the RF to DC converter was design and simulated using Intelligent Schematic Input System (ISIS Proteus.

  11. Energy-Efficient Power Allocation for Underlay Cognitive Radio Systems

    KAUST Repository

    Sboui, Lokman

    2015-09-01

    We present a power allocation framework for spectrum sharing Cognitive Radio (CR) systems based on maximizing the energy efficiency (EE). First, we show that the relation between the EE and the spectral efficiency (SE) is strictly increasing in contrast with the SE-EE trade-off discussed in the literature. We also solve a non-convex problem and explicitly derive the optimal power for the proposed average EE under either a peak or an average power constraint. We apply our results to the underlay CR systems where the power is limited by an additional interference constraint. When the instantaneous channel is not available, we provide a necessary and sufficient condition for the optimal power and present a simple sub-optimal power. In the numerical results, we show that the proposed EE corresponds to a higher SE at mid-range and high power regime compared to the classical EE. We also show that the sup-optimal solution is very close to the optimal solution. In addition, we deduce that the absence of instantaneous CSI affects the EE and the SE at high power regime compared to full CSI. In the CR context, we show that the interference threshold has a minimal effect on the EE compared to the SE.

  12. Energy-Efficient Power Allocation for Underlay Cognitive Radio Systems

    KAUST Repository

    Sboui, Lokman; Rezki, Zouheir; Alouini, Mohamed-Slim

    2015-01-01

    We present a power allocation framework for spectrum sharing Cognitive Radio (CR) systems based on maximizing the energy efficiency (EE). First, we show that the relation between the EE and the spectral efficiency (SE) is strictly increasing in contrast with the SE-EE trade-off discussed in the literature. We also solve a non-convex problem and explicitly derive the optimal power for the proposed average EE under either a peak or an average power constraint. We apply our results to the underlay CR systems where the power is limited by an additional interference constraint. When the instantaneous channel is not available, we provide a necessary and sufficient condition for the optimal power and present a simple sub-optimal power. In the numerical results, we show that the proposed EE corresponds to a higher SE at mid-range and high power regime compared to the classical EE. We also show that the sup-optimal solution is very close to the optimal solution. In addition, we deduce that the absence of instantaneous CSI affects the EE and the SE at high power regime compared to full CSI. In the CR context, we show that the interference threshold has a minimal effect on the EE compared to the SE.

  13. Enhanced cognitive Radio Resource Management for LTE systems

    KAUST Repository

    Alqerm, Ismail; Shihada, Basem; Shin, Kang G.

    2013-01-01

    as it improves network efficiency by exploiting radio environment information, intelligent optimization algorithms to configure transmission parameters, and mitigate interference. In this paper, we propose a cognitive resource management scheme to adapt LTE

  14. On the Capacity of Underlay Cognitive Radio Systems

    KAUST Repository

    Sboui, Lokman

    2013-01-01

    Due to the scarcity of frequency spectrum in view of the evolution of wireless communication technologies, the cognitive radio (CR) concept has been introduced to efficiently exploit the available spectrum. This concept consists in introducing

  15. Comparison of accuracy and safety of the SEVEN and the Navigator continuous glucose monitoring systems.

    Science.gov (United States)

    Garg, Satish K; Smith, James; Beatson, Christie; Lopez-Baca, Benita; Voelmle, Mary; Gottlieb, Peter A

    2009-02-01

    This study evaluated the accuracy and safety of two continuous glucose monitoring (CGM) systems, the SEVEN (DexCom, San Diego, CA) and the Navigator (Abbott Diabetes Care, Alameda, CA), with the YSI laboratory measurements of blood glucose (blood glucose meter manufactured by YSI, Yellow Springs, OH), when worn concurrently in adults with type 1 diabetes. Fourteen subjects with type 1 diabetes, 33 +/- 6 (mean +/- SD) years old, were enrolled in this study. All subjects wore both sensors concurrently over three consecutive 5-day CGM sessions (15-day wear). On Days 5, 10, and 15, subjects participated in an 8-h in-clinic session where measurements from the CGM systems were collected and compared with YSI measurements every 15 min. At the end of Day 5 and 10 in-clinic sessions, the sensors were removed, and new sensors were inserted for the following CGM session despite the SEVEN system's recommended use for up to 7 days. The mean absolute relative difference (ARD) for the two CGM devices versus YSI was not different: 16.8% and 16.1% for SEVEN and Navigator, respectively (P = 0.38). In the hypoglycemic region (YSI value blood glucose (SMBG) values. Thirteen additional Navigator replacement devices were issued compared to two for the SEVEN. A total of three versus 14 skin reactions were reported with the SEVEN and Navigator insertion area, respectively. Glucose measurements with the SEVEN and Navigator were found to be similar compared with YSI and SMBG measurements, with the exception of the hypoglycemic range where the SEVEN performed better. However, the Navigator caused more skin area reactions.

  16. 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.

  17. Learning to navigate the healthcare system in a new country: a qualitative study.

    Science.gov (United States)

    Straiton, Melanie L; Myhre, Sonja

    2017-12-01

    Learning to navigate a healthcare system in a new country is a barrier to health care. Understanding more about the specific navigation challenges immigrants experience may be the first step towards improving health information and thus access to care. This study considers the challenges that Thai and Filipino immigrant women encounter when learning to navigate the Norwegian primary healthcare system and the strategies they use. A qualitative interview study using thematic analysis. Norway. Fifteen Thai and 15 Filipino immigrant women over the age of 18 who had been living in Norway at least one year. The women took time to understand the role of the general practitioner and some were unaware of their right to an interpreter during consultations. In addition to reliance on family members and friends in their social networks, voluntary and cultural organisations provided valuable tips and advice on how to navigate the Norwegian health system. While some women actively engaged in learning more about the system, they noted a lack of information available in multiple languages. Informal sources play an important role in learning about the health care system. Formal information should be available in different languages in order to better empower immigrant women.

  18. Learning to navigate the healthcare system in a new country: a qualitative study

    Science.gov (United States)

    Straiton, Melanie L.; Myhre, Sonja

    2017-01-01

    Objective Learning to navigate a healthcare system in a new country is a barrier to health care. Understanding more about the specific navigation challenges immigrants experience may be the first step towards improving health information and thus access to care. This study considers the challenges that Thai and Filipino immigrant women encounter when learning to navigate the Norwegian primary healthcare system and the strategies they use. Design A qualitative interview study using thematic analysis. Setting Norway. Participants Fifteen Thai and 15 Filipino immigrant women over the age of 18 who had been living in Norway at least one year. Results The women took time to understand the role of the general practitioner and some were unaware of their right to an interpreter during consultations. In addition to reliance on family members and friends in their social networks, voluntary and cultural organisations provided valuable tips and advice on how to navigate the Norwegian health system. While some women actively engaged in learning more about the system, they noted a lack of information available in multiple languages. Conclusions Informal sources play an important role in learning about the health care system. Formal information should be available in different languages in order to better empower immigrant women. PMID:29087232

  19. From COST 271 to 296 EU actions on ionospheric monitoring and modelling for terrestrial and Earth space radio systems

    Science.gov (United States)

    Zolesi, B.; Cander, Lj. R.; Altadill, D.

    The ionospheric community has long been aware that co-operative research on an international basis is essential to deal with temporal and spatial changes in the ionosphere that influence the performance of terrestrial and Earth-space radio systems. The EU COST (Co-operation in the field of Scientific and Technical Research) 271 Action on "Effects of the Upper Atmosphere on Terrestrial and Earth-space Communications" has had during the period of October 2000-August 2004 the following main objectives: (1) to evaluate the influence of upper atmospheric conditions on terrestrial and Earth-space communications, (2) to develop methods and techniques to improve ionospheric models over Europe for telecommunication and navigation applications and (3) to transfer the results to the appropriate radiocommunication study groups of the International Telecommunication Union (ITU-R) and other national and international organizations dealing with the modern communication systems. At the beginning of 2005 the new 296 Action in the COST Telecommunications, Information Science and Technology domain on "Mitigation of Ionospheric Effects on Radio Systems (MIERS)" was approved for the period 2005-2009. The main objectives of the MIERS are: (a) to support and enhanced the existing European facilities for historical and real-time digital ionospheric data collection and exchange; (b) to develop an integrated approach to ionospheric modelling, create the mechanism needed to ingest processed data into models, extend and develop suitable mitigation models and define the protocols needed to link models together; and (c) to strengthen the areas of expertise that already exist by stimulating closer cooperation between scientists and users, focusing the scope of all the previous COST ionospheric related studies to the mitigation of ionospheric effects on radio systems. This paper summarises briefly how the major objectives of the COST271 Action have been achieved and what are the most important

  20. 47 CFR 90.656 - Responsibilities of base station licensees of Specialized Mobile Radio systems.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Responsibilities of base station licensees of... Bands § 90.656 Responsibilities of base station licensees of Specialized Mobile Radio systems. (a) The licensees of base stations that provide Specialized Mobile Radio service on a commercial basis of the use of...

  1. Navigated Pattern Laser System versus Single-Spot Laser System for Postoperative 360-Degree Laser Retinopexy.

    Science.gov (United States)

    Kulikov, Alexei N; Maltsev, Dmitrii S; Boiko, Ernest V

    2016-01-01

    Purpose . To compare three 360°-laser retinopexy (LRP) approaches (using navigated pattern laser system, single-spot slit-lamp (SL) laser delivery, and single-spot indirect ophthalmoscope (IO) laser delivery) in regard to procedure duration, procedural pain score, technical difficulties, and the ability to achieve surgical goals. Material and Methods . Eighty-six rhegmatogenous retinal detachment patients (86 eyes) were included in this prospective randomized study. The mean procedural time, procedural pain score (using 4-point Verbal Rating Scale), number of laser burns, and achievement of the surgical goals were compared between three groups (pattern LRP (Navilas® laser system), 36 patients; SL-LRP, 28 patients; and IO-LRP, 22 patients). Results . In the pattern LRP group, the amount of time needed for LRP and pain level were statistically significantly lower, whereas the number of applied laser burns was higher compared to those in the SL-LRP group and in the IO-LRP group. In the pattern LRP, SL-LRP, and IO-LRP groups, surgical goals were fully achieved in 28 (77.8%), 17 (60.7%), and 13 patients (59.1%), respectively ( p > 0.05). Conclusion . The navigated pattern approach allows improving the treatment time and pain in postoperative 360° LRP. Moreover, 360° pattern LRP is at least as effective in achieving the surgical goal as the conventional (slit-lamp or indirect ophthalmoscope) approaches with a single-spot laser.

  2. Location-Based Resource Allocation for OFDMA Cognitive Radio Systems

    KAUST Repository

    Ghorbel, Mahdi

    2011-05-01

    Cognitive radio is one of the hot topics for emerging and future wireless communication. It has been proposed as a suitable solution for the spectrum scarcity caused by the increase in frequency demand. The concept is based on allowing unlicensed users, called cognitive or secondary users, to share the unoccupied frequency bands with their owners, called the primary users, under constraints on the interference they cause to them. In order to estimate this interference, the cognitive system usually uses the channel state information to the primary user, which is often impractical to obtain. However, we propose to use location information, which is easier to obtain, to estimate this interference. The purpose of this work is to propose a subchannel and power allocation method which maximizes the secondary users\\' total capacity under the constraints of limited budget power and total interference to the primary under certain threshold. We model the problem as a constrained optimization problem for both downlink and uplink cases. Then, we propose low-complexity resource allocation schemes based on the waterfilling algorithm. The simulation results show the efficiency of the proposed method with comparison to the exhaustive search algorithm.

  3. Design and Flight Performance of the Orion Pre-Launch Navigation System

    Science.gov (United States)

    Zanetti, Renato

    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 test the prelaunch and entry components of the system. Orion's pre-launch absolute navigation design is presented, together with its EFT-1 performance.

  4. 77 FR 50420 - Proposed Provision of Navigation Services for the Next Generation Air Transportation System...

    Science.gov (United States)

    2012-08-21

    ... Air Transportation System (NextGen) Transition to Performance-Based Navigation (PBN); Disposition of... safety, minimize economic impacts from GPS outages within the NAS and support air transportation's timing... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Parts 91, 97, 121, 125, 129...

  5. 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

  6. Behaviour based Mobile Robot Navigation Technique using AI System: Experimental Investigation on Active Media Pioneer Robot

    Directory of Open Access Journals (Sweden)

    S. Parasuraman, V.Ganapathy

    2012-10-01

    Full Text Available A key issue in the research of an autonomous robot is the design and development of the navigation technique that enables the robot to navigate in a real world environment. In this research, the issues investigated and methodologies established include (a Designing of the individual behavior and behavior rule selection using Alpha level fuzzy logic system  (b Designing of the controller, which maps the sensors input to the motor output through model based Fuzzy Logic Inference System and (c Formulation of the decision-making process by using Alpha-level fuzzy logic system. The proposed method is applied to Active Media Pioneer Robot and the results are discussed and compared with most accepted methods. This approach provides a formal methodology for representing and implementing the human expert heuristic knowledge and perception-based action in mobile robot navigation. In this approach, the operational strategies of the human expert driver are transferred via fuzzy logic to the robot navigation in the form of a set of simple conditional statements composed of linguistic variables.Keywards: Mobile robot, behavior based control, fuzzy logic, alpha level fuzzy logic, obstacle avoidance behavior and goal seek behavior

  7. An Outdoor Navigation System for Blind Pedestrians Using GPS and Tactile-Foot Feedback

    Directory of Open Access Journals (Sweden)

    Ramiro Velázquez

    2018-04-01

    Full Text Available This paper presents a novel, wearable navigation system for visually impaired and blind pedestrians that combines a global positioning system (GPS for user outdoor localization and tactile-foot stimulation for information presentation. Real-time GPS data provided by a smartphone are processed by dedicated navigation software to determine the directions to a destination. Navigational directions are then encoded as vibrations and conveyed to the user via a tactile display that inserts into the shoe. The experimental results showed that users were capable of recognizing with high accuracy the tactile feedback provided to their feet. The preliminary tests conducted in outdoor locations involved two blind users who were guided along 380–420 m predetermined pathways, while sharing the space with other pedestrians and facing typical urban obstacles. The subjects successfully reached the target destinations. The results suggest that the proposed system enhances independent, safe navigation of blind pedestrians and show the potential of tactile-foot stimulation in assistive devices.

  8. SEXTANT X-Ray Pulsar Navigation Demonstration: Flight System and Test Results

    Science.gov (United States)

    Winternitz, Luke; Mitchell, Jason W.; Hassouneh, Munther A.; Valdez, Jennifer E.; Price, Samuel R.; Semper, Sean R.; Yu, Wayne H.; Ray, Paul S.; Wood, Kent S.; Arzoumanian, Zaven; hide

    2016-01-01

    The Station Explorer for X-ray Timing and Navigation Technology (SEXTANT) is a technology demonstration enhancement to the Neutron-star Interior Composition Explorer (NICER) mission. NICER is a NASA Explorer Mission of Opportunity that will be hosted on the International Space Station (ISS). SEXTANT will, for the first time, demonstrate real-time, on-board X-ray Pulsar Navigation (XNAV), a significant milestone in the quest to establish a GPS-like navigation capability available throughout our Solar System and beyond. This paper gives an overview of the SEXTANT system architecture and describes progress prior to environmental testing of the NICER flight instrument. It provides descriptions and development status of the SEXTANT flight software and ground system, as well as detailed description and results from the flight software functional and performance testing within the high-fidelity Goddard Space Flight Center (GSFC) X-ray Navigation Laboratory Testbed (GXLT) software and hardware simulation environment. Hardware-in-the-loop simulation results are presented, using the engineering model of the NICER timing electronics and the GXLT pulsar simulator-the GXLT precisely controls NASA GSFC's unique Modulated X-ray Source to produce X-rays that make the NICER detector electronics appear as if they were aboard the ISS viewing a sequence of millisecond pulsars

  9. Precise Point Positioning with the BeiDou Navigation Satellite System

    Directory of Open Access Journals (Sweden)

    Min Li

    2014-01-01

    Full Text Available By the end of 2012, China had launched 16 BeiDou-2 navigation satellites that include six GEOs, five IGSOs and five MEOs. This has provided initial navigation and precise pointing services ability in the Asia-Pacific regions. In order to assess the navigation and positioning performance of the BeiDou-2 system, Wuhan University has built up a network of BeiDou Experimental Tracking Stations (BETS around the World. The Position and Navigation Data Analyst (PANDA software was modified to determine the orbits of BeiDou satellites and provide precise orbit and satellite clock bias products from the BeiDou satellite system for user applications. This article uses the BeiDou/GPS observations of the BeiDou Experimental Tracking Stations to realize the BeiDou and BeiDou/GPS static and kinematic precise point positioning (PPP. The result indicates that the precision of BeiDou static and kinematic PPP reaches centimeter level. The precision of BeiDou/GPS kinematic PPP solutions is improved significantly compared to that of BeiDou-only or GPS-only kinematic PPP solutions. The PPP convergence time also decreases with the use of combined BeiDou/GPS systems.

  10. Precise point positioning with the BeiDou navigation satellite system.

    Science.gov (United States)

    Li, Min; Qu, Lizhong; Zhao, Qile; Guo, Jing; Su, Xing; Li, Xiaotao

    2014-01-08

    By the end of 2012, China had launched 16 BeiDou-2 navigation satellites that include six GEOs, five IGSOs and five MEOs. This has provided initial navigation and precise pointing services ability in the Asia-Pacific regions. In order to assess the navigation and positioning performance of the BeiDou-2 system, Wuhan University has built up a network of BeiDou Experimental Tracking Stations (BETS) around the World. The Position and Navigation Data Analyst (PANDA) software was modified to determine the orbits of BeiDou satellites and provide precise orbit and satellite clock bias products from the BeiDou satellite system for user applications. This article uses the BeiDou/GPS observations of the BeiDou Experimental Tracking Stations to realize the BeiDou and BeiDou/GPS static and kinematic precise point positioning (PPP). The result indicates that the precision of BeiDou static and kinematic PPP reaches centimeter level. The precision of BeiDou/GPS kinematic PPP solutions is improved significantly compared to that of BeiDou-only or GPS-only kinematic PPP solutions. The PPP convergence time also decreases with the use of combined BeiDou/GPS systems.

  11. Optical Fiber Connection Navigation System Using Visible Light Communication in Central Office with Economic Evaluation

    Science.gov (United States)

    Waki, Masaki; Uruno, Shigenori; Ohashi, Hiroyuki; Manabe, Tetsuya; Azuma, Yuji

    We propose an optical fiber connection navigation system that uses visible light communication for an integrated distribution module in a central office. The system realizes an accurate database, requires less skilled work to operate and eliminates human error. This system can achieve a working time reduction of up to 88.0% compared with the conventional work without human error for the connection/removal of optical fiber cords, and is economical as regards installation and operation.

  12. Adaptive algorithm based on antenna arrays for radio communication systems

    Directory of Open Access Journals (Sweden)

    Fedosov Valentin

    2017-01-01

    always noticeably accelerate traffic at short distances from the access point, but, they are very effective at long distances. The MIMO principle allows reducing the number of errors in radio data interchange (BER without reducing the transmission rate under conditions of multiple signal re-reflections. The work aims at developing an adaptive space-time signal algorithm for a wireless data transmission system designed to improve the efficiency of this system, as well as to study the efficiency of the algorithm to minimizing the error bit probability and maximizing the channel capacity.

  13. Electromagnetic Interference to Flight Navigation and Communication Systems: New Strategies in the Age of Wireless

    Science.gov (United States)

    Ely, Jay J.

    2005-01-01

    Electromagnetic interference (EMI) promises to be an ever-evolving concern for flight electronic systems. This paper introduces EMI and identifies its impact upon civil aviation radio systems. New wireless services, like mobile phones, text messaging, email, web browsing, radio frequency identification (RFID), and mobile audio/video services are now being introduced into passenger airplanes. FCC and FAA rules governing the use of mobile phones and other portable electronic devices (PEDs) on board airplanes are presented along with a perspective of how these rules are now being rewritten to better facilitate in-flight wireless services. This paper provides a comprehensive overview of NASA cooperative research with the FAA, RTCA, airlines and universities to obtain laboratory radiated emission data for numerous PED types, aircraft radio frequency (RF) coupling measurements, estimated aircraft radio interference thresholds, and direct-effects EMI testing. These elements are combined together to provide high-confidence answers regarding the EMI potential of new wireless products being used on passenger airplanes. This paper presents a vision for harmonizing new wireless services with aeronautical radio services by detecting, assessing, controlling and mitigating the effects of EMI.

  14. 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.

  15. Plasma phenomenology in astrophysical systems: Radio-sources and jets

    International Nuclear Information System (INIS)

    Montani, Giovanni; Petitta, Jacopo

    2014-01-01

    We review the plasma phenomenology in the astrophysical sources which show appreciable radio emissions, namely Radio-Jets from Pulsars, Microquasars, Quasars, and Radio-Active Galaxies. A description of their basic features is presented, then we discuss in some details the links between their morphology and the mechanisms that lead to the different radio-emissions, investigating especially the role played by the plasma configurations surrounding compact objects (Neutron Stars, Black Holes). For the sake of completeness, we briefly mention observational techniques and detectors, whose structure set them apart from other astrophysical instruments. The fundamental ideas concerning angular momentum transport across plasma accretion disks—together with the disk-source-jet coupling problem—are discussed, by stressing their successes and their shortcomings. An alternative scenario is then inferred, based on a parallelism between astrophysical and laboratory plasma configurations, where small-scale structures can be found. We will focus our attention on the morphology of the radio-jets, on their coupling with the accretion disks and on the possible triggering phenomena, viewed as profiles of plasma instabilities

  16. Improvement on control system of the JT-60 radio frequency heating system

    Energy Technology Data Exchange (ETDEWEB)

    Shinozaki, Shin-ichi; Moriyama, Shinichi; Hiranai, Shinichi [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment; Sato, Fumiaki [Nippon Advanced Technology Co., Ltd., Tokai, Ibaraki (Japan)

    2003-03-01

    On the JT-60 radio frequency (RF) heating system, the decrease in the activity ratio was a problem because of the deterioration of the control system. To improve the reliability, we replaced CAMAC system for a power injection control system, which was a main cause of the trouble, with the microprocessor system. And, a function of computer supported programming function of RF power injection form was introduced, which contributed to reduce a load of operators. Furthermore, personal computers with network communication were introduced to improve a maintenance ability of the control system. As a result, the activity ratio of the RF heating system was improved significantly. (author)

  17. Extended investigation into continuous laser scanning of underground mine workings by means of Landis inertial navigation system

    Science.gov (United States)

    Belyaev, E. N.

    2017-10-01

    The paper investigates the method of applying mobile scanning systems (MSSs) with inertial navigators in the underground conditions for carrying out the surveying tasks. The available mobile laser scanning systems cannot be used in the underground environment since Global Positioning System (GPS) signals cannot be received in mines. This signal not only is necessary for space positioning, but also operates as the main corrective signal for the primary navigation system - the inertial navigation system. The idea of the method described in this paper consists in using MSSs with a different correction of the inertial system than GPS is.

  18. Real-time Risk Assessment for Aids to Navigation Using Fuzzy-FSA on Three-Dimensional Simulation System

    OpenAIRE

    Jinbiao Chen; Chaojian Shi; Dongxing Jia

    2014-01-01

    The risk level of the Aids to Navigation (AtoNs) can reflect the ship navigation safety level in the channel to some extent. In order to appreciate the risk level of the aids to navigation (AtoNs) in a navigation channel and to provide some decision-making suggestions for the AtoNs Maintenance and Management Department, the risk assessment index system of the AtoNs was built considering the advanced experience of IALA. Under the Formal Safety Assessment frame, taking the advantages of the fuz...

  19. Performance evaluation of a real time OFDM radio over fiber system at 2.5 GHz using software defined radio SDR

    DEFF Research Database (Denmark)

    David Cepeda, Juan; Rodriguez, Santiago Isaac; Rico-Martinez, Monica

    2017-01-01

    This paper presents the implementation of an OFDM radio over fiber (RoF) system at 2.5 GHz using software defined radio (SDR). In this work, first we present an introduction of the main concepts about radio over fiber and an orthogonal frequency-division multiplexing (OFDM) system at 2.5 GHz......, then we present a comparison of an OFDM RoF system in three scenarios, modifying the wireless distances and the optical fiber distance in order to evaluate the performance of the system taking into account the symbol error rate (SER) vs signal to noise ratio (SNR) curves....

  20. 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

  1. The skill of surface registration in CT-based navigation system for total hip arthroplasty

    International Nuclear Information System (INIS)

    Hananouchi, T.; Sugano, N.; Nishii, T.; Miki, H.; Sakai, T.; Yoshikawa, H.; Iwana, D.; Yamamura, M.; Nakamura, N.

    2007-01-01

    Surface registration of the CT-based navigation system, which is a matching between computational and real spatial spaces, is a key step to guarantee the accuracy of navigation. However, it has not been well described how the accuracy is affected by the registration skill of surgeon. Here, we reported the difference of the registration error between eight surgeons with the experience of navigation and six apprentice surgeons. A cadaveric pelvic model with an acetabular cup was made to measure the skill and learning curve of registration. After surface registration, two cup angles (inclination and anteversion) were recorded in the navigation system and the variance of these cup angles in ten trials were compared between the experienced surgeons and apprentices. In addition, we investigated whether the accuracy of registration by the apprentices was improved by visual information on how to take the surface points. The results showed that there was statistically significant difference in the accuracy of registration between the two groups. The accuracy of the second ten trials after getting the visual information showed great improvements. (orig.)

  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. Common Submarine Radio Room: A Case Study of a System of Systems Approach

    Science.gov (United States)

    2014-09-01

    circuits at that time required many steps to lineup , providing opportunities for operator error (NUWC 2008, 15). The USS Seawolf (SW) class, designed...The OE-538 antenna group is an improved, multifunctional, combined communications, navigation and Identification Friend or Foe (IFF) mast-mounted... Identification that a number of aeronautical systems did not meet the performance baseline configuration forced a reconfiguration of a number of

  4. Design and implementation of a navigation control system for slag ...

    Indian Academy of Sciences (India)

    Masoud Gholami

    2018-03-10

    Mar 10, 2018 ... were required to constantly communicate using wireless system. This caused heavy work load and sometimes interrupted their main tasks. Replacing the traditional communication methods by a smart system relieved the staff from the heavy work load. 4. Conclusion. During the steel production process, the ...

  5. Secondary Victimization: Domestic Violence Survivors Navigating the Family Law System.

    Science.gov (United States)

    Laing, Lesley

    2016-08-23

    This qualitative study explored the experiences of 22 domestic violence survivors attempting to negotiate safe post-separation parenting arrangements through the Australian family law system. Their allegations of violence put them at odds with a system that values mediated settlements and shared parenting. Skeptical responses, accusations of parental alienation, and pressure to agree to unsafe arrangements exacerbated the effects of post-separation violence. Core themes in the women's narratives of engagement with the family law system-silencing, control, and undermining the mother-child relationship-mirrored domestic violence dynamics, suggesting the concept of secondary victimization as a useful lens for understanding their experiences. © The Author(s) 2016.

  6. Towards Reliable, Scalable, and Energy Efficient Cognitive Radio Systems

    KAUST Repository

    Sboui, Lokman

    2017-11-01

    The cognitive radio (CR) concept is expected to be adopted along with many technologies to meet the requirements of the next generation of wireless and mobile systems, the 5G. Consequently, it is important to determine the performance of the CR systems with respect to these requirements. In this thesis, after briefly describing the 5G requirements, we present three main directions in which we aim to enhance the CR performance. The first direction is the reliability. We study the achievable rate of a multiple-input multiple-output (MIMO) relay-assisted CR under two scenarios; an unmanned aerial vehicle (UAV) one-way relaying (OWR) and a fixed two-way relaying (TWR). We propose special linear precoding schemes that enable the secondary user (SU) to take advantage of the primary-free channel eigenmodes. We study the SU rate sensitivity to the relay power, the relay gain, the UAV altitude, the number of antennas and the line of sight availability. The second direction is the scalability. We first study a multiple access channel (MAC) with multiple SUs scenario. We propose a particular linear precoding and SUs selection scheme maximizing their sum-rate. We show that the proposed scheme provides a significant sum-rate improvement as the number of SUs increases. Secondly, we expand our scalability study to cognitive cellular networks. We propose a low-complexity algorithm for base station activation/deactivation and dynamic spectrum management maximizing the profits of primary and secondary networks subject to green constraints. We show that our proposed algorithms achieve performance close to those obtained with the exhaustive search method. The third direction is the energy efficiency (EE). We present a novel power allocation scheme based on maximizing the EE of both single-input and single-output (SISO) and MIMO systems. We solve a non-convex problem and derive explicit expressions of the corresponding optimal power. When the instantaneous channel is not available, we

  7. Development of offroad unmanned dump truck navigation system. Dump truck mujin soko system no kaihatsu ni tsuite

    Energy Technology Data Exchange (ETDEWEB)

    Horii, Z [Nittetsu Mining Co. Ltd., Tokyo (Japan)

    1992-08-25

    A large offroad unmanned dump truck navigation system has been developed, and is in practical operation mounted on dump trucks at Torigatayama Limestone Quarry of Nittetsu Mining Company. The system functions in a manual dump truck navigation mode, wireless navigation mode, and unmanned control mode. The unmanned control mode further includes a mode to navigate the truck on a predetermined course with its data having been input in a computer and a mode that when the truck was moved on a course under a wireless control, the computer learns the course and drives the truck autonomously thereafter. The safety measures are divided into the hardware safety function to detect abnormalities in brakes and other vehicle parts, and the software safety functions of data communications, sensor action check, and prevention of collision of trucks with each other. The system has resulted in a productivity of average one-way travel distance of 345 m, and average unmanned navigation cycle time of 9 minutes and 26 seconds for a transportation efficiency of 541 t/hour/truck, having reached at least the manned operation level. 4 figs., 1 tab.

  8. Method and Tool for Design Process Navigation and Automatic Generation of Simulation Models for Manufacturing Systems

    Science.gov (United States)

    Nakano, Masaru; Kubota, Fumiko; Inamori, Yutaka; Mitsuyuki, Keiji

    Manufacturing system designers should concentrate on designing and planning manufacturing systems instead of spending their efforts on creating the simulation models to verify the design. This paper proposes a method and its tool to navigate the designers through the engineering process and generate the simulation model automatically from the design results. The design agent also supports collaborative design projects among different companies or divisions with distributed engineering and distributed simulation techniques. The idea was implemented and applied to a factory planning process.

  9. Application of talairach coordinates for transcranial magnetic stimulation navigation system

    International Nuclear Information System (INIS)

    Ahn, Se-Jong; Kim, Jong-Woo; Sin, Sung-Wook; Yoo, Jin-Young; An, Hyojin; Chung, Sung-Taek; Yoon, Sejin

    2011-01-01

    Since the development of transcranial magnetic stimulation (TMS) in 1985, its clinical and experimental studies and therapeutic applications have been widely being investigated. MRI-based neuronavigational systems have been developed and used for positioning of the magnetic coil, which is the main problem of most TMS studies. The functional brain map provided by these systems, however, may be unsuitable for a population-based study since it does not describe the location of brain structures independent from individual differences in brain, and also, it would be difficult to localize particular point of brain since there is no reference point excepting anatomical structure. In this paper, neuronavigational approach of TMS and application of Talairach coordinate system are introduced. We expect that this concept of the system will allow not only to perform the population-based study taking individual anatomy into account, but also to help physician to localize specific point in the Talairach coordinates. (author)

  10. Radio stars

    International Nuclear Information System (INIS)

    Hjellming, R.M.; Gibson, D.M.

    1985-01-01

    Studies of stellar radio emission became an important field of research in the 1970's and have now expanded to become a major area of radio astronomy with the advent of new instruments such as the Very Large Array in New Mexico and transcontinental telescope arrays. This volume contains papers from the workshop on stellar continuum radio astronomy held in Boulder, Colorado, and is the first book on the rapidly expanding field of radio emission from stars and stellar systems. Subjects covered include the observational and theoretical aspects of stellar winds from both hot and cool stars, radio flares from active double star systems and red dwarf stars, bipolar flows from star-forming regions, and the radio emission from X-ray binaries. (orig.)

  11. Primary user localisation and uplink resource allocation in orthogonal frequency division multiple access cognitive radio systems

    KAUST Repository

    Nam, Haewoon; Saeed, Nasir; Ben Ghorbel, Mahdi; Alouini, Mohamed-Slim

    2015-01-01

    In cognitive radio networks, secondary users (SUs) can share spectrum with primary users (PUs) under the condition that no interference is caused to the PUs. To evaluate the interference imposed to the PUs, the cognitive systems discussed

  12. Generalized location-based resource allocation for OFDMA cognitive radio systems

    KAUST Repository

    Ben Ghorbel, Mahdi; Nam, Haewoon; Alouini, Mohamed-Slim

    2010-01-01

    Cognitive radio is one of the hot topics for emerging and future wireless communication. Cognitive users can share channels with primary users under the condition of non interference. In order to compute this interference, the cognitive system

  13. Analytical Frameworks of Cooperative and Cognitive Radio Systems with Practical Considerations

    KAUST Repository

    Khan, Fahd Ahmed

    2013-01-01

    for cooperative and cognitive radio systems considering real world scenarios and to make these technologies implementable. In most of the research on cooperative relaying, it has been assumed that the communicating nodes have perfect channel state information

  14. Recent Advances in Radio and Optical Propagation for Modern Communications, Navigation and Detection Systems

    Science.gov (United States)

    1978-04-01

    water, it the relative humidity reaches values above 70%. The dependence of humidity and windspeed has not beer incorporated in the model which...electromagnetic energy by the molecules at specific electromagnetic wave- lengths. In the case of a gas, this absorption phenomenon is covered by the Beer ...the object of interest may emit (scent from plants, odours from fermenting organic substances, gases from soil, exhaust gases from vehicles etc). - The

  15. 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

  16. 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.

  17. a European Global Navigation Satellite System — the German Market and Value Adding Chain Effects

    Science.gov (United States)

    Vollerthun, A.; Wieser, M.

    2002-03-01

    Since Europe is considering to establish a "market-driven" European Global Navigation Satellite System, the German Center of Aerospace initiated a market research to justify a German investment in such a European project. The market research performed included the following market segments: aviation, railway, road traffic, shipping, surveying, farming, military, space applications, leisure, and sport. In these market segments, the forementioned inputs were determined for satellite navigation hardware (receivers) as well as satellite navigation services. The forecast period was from year 2007 to 2017. For the considered period, the market amounts to a total of DM 83.0 billion (approx. US $50 billion), whereas the satellite navigation equipment market makes up DM 39.8 billion, and charges for value-added-services amount to DM 43.2 billion. On closer examination road traffic can be identified as the dominant market share, both in the receiver-market and service-market. With a share of 96% for receivers and 73% for services the significance of the road traffic segment becomes obvious. The second part of this paper investigates the effects the market potential has on the Value-Adding-Chain. Therefore, all participants in the Value-Adding-Chain are identified, using industrial cost structure models the employment effect is analyzed, and possible tax revenues for the state are examined.

  18. Observability during planetary approach navigation

    Science.gov (United States)

    Bishop, Robert H.; Burkhart, P. Daniel; Thurman, Sam W.

    1993-01-01

    The objective of the research is to develop an analytic technique to predict the relative navigation capability of different Earth-based radio navigation measurements. In particular, the problem is to determine the relative ability of geocentric range and Doppler measurements to detect the effects of the target planet gravitational attraction on the spacecraft during the planetary approach and near-encounter mission phases. A complete solution to the two-dimensional problem has been developed. Relatively simple analytic formulas are obtained for range and Doppler measurements which describe the observability content of the measurement data along the approach trajectories. An observability measure is defined which is based on the observability matrix for nonlinear systems. The results show good agreement between the analytic observability analysis and the computational batch processing method.

  19. A Method for The Assessing of Reliability Characteristics Relevant to an Assumed Position-Fixing Accuracy in Navigational Positioning Systems

    Directory of Open Access Journals (Sweden)

    Specht Cezary

    2016-09-01

    Full Text Available This paper presents a method which makes it possible to determine reliability characteristics of navigational positioning systems, relevant to an assumed value of permissible error in position fixing. The method allows to calculate: availability , reliability as well as operation continuity of position fixing system for an assumed, determined on the basis of formal requirements - both worldwide and national, position-fixing accuracy. The proposed mathematical model allows to satisfy, by any navigational positioning system, not only requirements as to position-fixing accuracy of a given navigational application (for air , sea or land traffic but also the remaining characteristics associated with technical serviceability of a system.

  20. On the Capacity of Underlay Cognitive Radio Systems

    KAUST Repository

    Sboui, Lokman

    2013-05-05

    Due to the scarcity of frequency spectrum in view of the evolution of wireless communication technologies, the cognitive radio (CR) concept has been introduced to efficiently exploit the available spectrum. This concept consists in introducing unlicensed/secondary users (SU’s) in existing networks to share the spectrum of licensed/primary users (PU’s) without harming primary communications hence the name of “spectrum sharing” technique. We study in this dissertation, the capacity and the achievable rate of the secondary user within various communication settings. We, firstly, investigate the capacity of the (SU’s) at low power regime for Nakagami fading channels and present closed form of the capacity under various types of interference and/or power constraints. We explicitly characterize two regimes where either the interference constraint or the power constraint dictates the optimal power profile. Our framework also highlights the effects of different fading parameters on the secondary link ergodic capacity. Interestingly, we show that the low power regime analysis provides a specific insight on the capacity behavior of CR that has not been reported by previous studies. Next, we determine the spectral efficiency gain of an uplink CR Multi-Input Multi- Output (MIMO) system in which the SU is allowed to share the spectrum with the PU using a specific precoding scheme to communicate with a common receiver. Applied to Rayleigh fading channels, we show, through numerical results, that our proposed scheme enhances considerably the cognitive achievable rate. For instance, in case of a perfect detection of the PU signal, after applying Successive Interference Cancellation (SIC), the CR rate remains non-zero for high Signal to Noise Ratio (SNR) which is usually impossible when we only use space alignment technique. In addition, we show that the rate gain is proportional to the allowed interference threshold by providing a fixed rate even in the high SNR range

  1. An Overview of Scientific and Space Weather Results from the Communication/Navigation Outage Forecasting System (C/NOFS) Mission

    Science.gov (United States)

    Pfaff, R.; de la Beaujardiere, O.; Hunton, D.; Heelis, R.; Earle, G.; Strauss, P.; Bernhardt, P.

    2012-01-01

    The Communication/Navigation Outage Forecasting System (C/NOFS) Mission of the Air Force Research Laboratory is described. C/NOFS science objectives may be organized into three categories: (1) to understand physical processes active in the background ionosphere and thermosphere in which plasma instabilities grow; (2) to identify mechanisms that trigger or quench the plasma irregularities responsible for signal degradation; and (3) to determine how the plasma irregularities affect the propagation of electromagnetic waves. The satellite was launched in April, 2008 into a low inclination (13 deg), elliptical (400 x 850 km) orbit. The satellite sensors measure the following parameters in situ: ambient and fluctuating electron densities, AC and DC electric and magnetic fields, ion drifts and large scale ion composition, ion and electron temperatures, and neutral winds. C/NOFS is also equipped with a GPS occultation receiver and a radio beacon. In addition to the satellite sensors, complementary ground-based measurements, theory, and advanced modeling techniques are also important parts of the mission. We report scientific and space weather highlights of the mission after nearly four years in orbit

  2. Cancellation of the Army’s Autonomous Navigation System

    Science.gov (United States)

    2012-08-02

    Auto/Truck Various Vehicle Leader/Follower, Road Following Google Driverless Vehicle Google Road Following Source: GAO presentation of data from Red...both of which are estimated to cost over $300,000 per system. However, Google’s Driverless Vehicle and the Southwest Research Institute’s Mobile

  3. A Low-Cost, Passive Navigation Training System for Image-Guided Spinal Intervention.

    Science.gov (United States)

    Lorias-Espinoza, Daniel; Carranza, Vicente González; de León, Fernando Chico-Ponce; Escamirosa, Fernando Pérez; Martinez, Arturo Minor

    2016-11-01

    Navigation technology is used for training in various medical specialties, not least image-guided spinal interventions. Navigation practice is an important educational component that allows residents to understand how surgical instruments interact with complex anatomy and to learn basic surgical skills such as the tridimensional mental interpretation of bidimensional data. Inexpensive surgical simulators for spinal surgery, however, are lacking. We therefore designed a low-cost spinal surgery simulator (Spine MovDigSys 01) to allow 3-dimensional navigation via 2-dimensional images without altering or limiting the surgeon's natural movement. A training system was developed with an anatomical lumbar model and 2 webcams to passively digitize surgical instruments under MATLAB software control. A proof-of-concept recognition task (vertebral body cannulation) and a pilot test of the system with 12 neuro- and orthopedic surgeons were performed to obtain feedback on the system. Position, orientation, and kinematic variables were determined and the lateral, posteroanterior, and anteroposterior views obtained. The system was tested with a proof-of-concept experimental task. Operator metrics including time of execution (t), intracorporeal length (d), insertion angle (α), average speed (v¯), and acceleration (a) were obtained accurately. These metrics were converted into assessment metrics such as smoothness of operation and linearity of insertion. Results from initial testing are shown and the system advantages and disadvantages described. This low-cost spinal surgery training system digitized the position and orientation of the instruments and allowed image-guided navigation, the generation of metrics, and graphic recording of the instrumental route. Spine MovDigSys 01 is useful for development of basic, noninnate skills and allows the novice apprentice to quickly and economically move beyond the basics. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. 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.

  5. 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.

  6. Radio Data System-Platform for traffic and travel information services

    Directory of Open Access Journals (Sweden)

    Claudiu Dan BARCA

    2017-03-01

    Full Text Available In the current National and European context where the public information is simultaneously spread on multiple channels and especially through mass-media channels, the text messaging services from public radio channels proved to be very useful and efficient for this purpose. Over the years, the use of a warning system like Radio Data System (RDS, at a global level shown, through text message or sound alarms is useful for the drivers to know the traffic, as well as for being aware of any emergency situations (fires, floods, earth-quakes. In this paper we present the characteristics of an RDS system with the Alert feature, as well as the study of radio covering of four from the Romanian National Radio News network's broadcasting points.

  7. THE RADIO JET ASSOCIATED WITH THE MULTIPLE V380 ORI SYSTEM

    Energy Technology Data Exchange (ETDEWEB)

    Rodríguez, Luis F.; Yam, J. Omar; Carrasco-González, Carlos [Instituto de Radioastronomía y Astrofísica, UNAM, Apdo. Postal 3-72 (Xangari), 58089 Morelia, Michoacán, México (Mexico); Anglada, Guillem [Instituto de Astrofísica de Andalucía, CSIC, Glorieta de la Astronomía, s/n, E-18008, Granada (Spain); Trejo, Alfonso, E-mail: l.rodriguez@crya.unam.mx [Academia Sinica Institute of Astronomy and Astrophysics, P.O. Box 23-141, Taipei 10617, Taiwan (China)

    2016-10-01

    The giant Herbig–Haro object 222 extends over ∼6′ in the plane of the sky, with a bow shock morphology. The identification of its exciting source has remained uncertain over the years. A non-thermal radio source located at the core of the shock structure was proposed to be the exciting source. However, Very Large Array studies showed that the radio source has a clear morphology of radio galaxy and a lack of flux variations or proper motions, favoring an extragalactic origin. Recently, an optical–IR study proposed that this giant HH object is driven by the multiple stellar system V380 Ori, located about 23′ to the SE of HH 222. The exciting sources of HH systems are usually detected as weak free–free emitters at centimeter wavelengths. Here, we report the detection of an elongated radio source associated with the Herbig Be star or with its close infrared companion in the multiple V380 Ori system. This radio source has the characteristics of a thermal radio jet and is aligned with the direction of the giant outflow defined by HH 222 and its suggested counterpart to the SE, HH 1041. We propose that this radio jet traces the origin of the large scale HH outflow. Assuming that the jet arises from the Herbig Be star, the radio luminosity is a few times smaller than the value expected from the radio–bolometric correlation for radio jets, confirming that this is a more evolved object than those used to establish the correlation.

  8. THE RADIO JET ASSOCIATED WITH THE MULTIPLE V380 ORI SYSTEM

    International Nuclear Information System (INIS)

    Rodríguez, Luis F.; Yam, J. Omar; Carrasco-González, Carlos; Anglada, Guillem; Trejo, Alfonso

    2016-01-01

    The giant Herbig–Haro object 222 extends over ∼6′ in the plane of the sky, with a bow shock morphology. The identification of its exciting source has remained uncertain over the years. A non-thermal radio source located at the core of the shock structure was proposed to be the exciting source. However, Very Large Array studies showed that the radio source has a clear morphology of radio galaxy and a lack of flux variations or proper motions, favoring an extragalactic origin. Recently, an optical–IR study proposed that this giant HH object is driven by the multiple stellar system V380 Ori, located about 23′ to the SE of HH 222. The exciting sources of HH systems are usually detected as weak free–free emitters at centimeter wavelengths. Here, we report the detection of an elongated radio source associated with the Herbig Be star or with its close infrared companion in the multiple V380 Ori system. This radio source has the characteristics of a thermal radio jet and is aligned with the direction of the giant outflow defined by HH 222 and its suggested counterpart to the SE, HH 1041. We propose that this radio jet traces the origin of the large scale HH outflow. Assuming that the jet arises from the Herbig Be star, the radio luminosity is a few times smaller than the value expected from the radio–bolometric correlation for radio jets, confirming that this is a more evolved object than those used to establish the correlation.

  9. Cislunar navigation

    Science.gov (United States)

    Cesarone, R. J.; Burke, J. D.; Hastrup, R. C.; Lo, M. W.

    2003-01-01

    In the future, navigation and communication in Earth-Moon space and on the Moon will differ from past practice due to evolving technology and new requirements. Here we describe likely requirements, discuss options for meeting them, and advocate steps that can be taken now to begin building the navcom systems needed in coming years for exploring and using the moon.

  10. Development of a prototype real-time automated filter for operational deep space navigation

    Science.gov (United States)

    Masters, W. C.; Pollmeier, V. M.

    1994-01-01

    Operational deep space navigation has been in the past, and is currently, performed using systems whose architecture requires constant human supervision and intervention. A prototype for a system which allows relatively automated processing of radio metric data received in near real-time from NASA's Deep Space Network (DSN) without any redesign of the existing operational data flow has been developed. This system can allow for more rapid response as well as much reduced staffing to support mission navigation operations.

  11. Meta-image navigation augmenters for unmanned aircraft systems (MINA for UAS)

    Science.gov (United States)

    Òªelik, Koray; Somani, Arun K.; Schnaufer, Bernard; Hwang, Patrick Y.; McGraw, Gary A.; Nadke, Jeremy

    2013-05-01

    GPS is a critical sensor for Unmanned Aircraft Systems (UASs) due to its accuracy, global coverage and small hardware footprint, but is subject to denial due to signal blockage or RF interference. When GPS is unavailable, position, velocity and attitude (PVA) performance from other inertial and air data sensors is not sufficient, especially for small UASs. Recently, image-based navigation algorithms have been developed to address GPS outages for UASs, since most of these platforms already include a camera as standard equipage. Performing absolute navigation with real-time aerial images requires georeferenced data, either images or landmarks, as a reference. Georeferenced imagery is readily available today, but requires a large amount of storage, whereas collections of discrete landmarks are compact but must be generated by pre-processing. An alternative, compact source of georeferenced data having large coverage area is open source vector maps from which meta-objects can be extracted for matching against real-time acquired imagery. We have developed a novel, automated approach called MINA (Meta Image Navigation Augmenters), which is a synergy of machine-vision and machine-learning algorithms for map aided navigation. As opposed to existing image map matching algorithms, MINA utilizes publicly available open-source geo-referenced vector map data, such as OpenStreetMap, in conjunction with real-time optical imagery from an on-board, monocular camera to augment the UAS navigation computer when GPS is not available. The MINA approach has been experimentally validated with both actual flight data and flight simulation data and results are presented in the paper.

  12. 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.

  13. 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.

  14. An advanced traveler navigation system adapted to route choice preferences of the individual users

    Directory of Open Access Journals (Sweden)

    Mahyar Amirgholy

    2017-12-01

    Full Text Available The majority of existing navigation systems only account for a single aspect of the route choice, like travel time or distance, in finding the optimal route for the trips in the network. In this research, we first identify a range of diverse factors that travelers take into account in their route choice decision in the network. A stated preference survey is conducted to show the heterogeneity in the preferences of users and its dependence to the purpose of the trips over the weekdays and weekends. Interestingly, results of the survey show that road safety is the most influential factor in the route choice decision of the average participants over weekends, exceeding even the travel time, and participants give more importance to the scenic quality of the routes for their weekend trips in comparison to their weekday trips. The results of the second part of the survey also indicate that in 27% of the cases participants choose routes other than the ones suggested by navigation systems, and 33% of the times that they take the suggested routes, they modify these routes according to their own preferences. The partial inability of existing navigation systems to suggest the routes that match the preferences of users can be attributed to ignoring (1 the diversity in influential factors and (2 the heterogeneity in preferences of the users by these systems. We propose a dynamic mixed logit route choice model to include the effects of information and learning to estimate parameters of a multivariable utility function for individual users based on their own historical route choice data over time. Finally, we present the concept of a smart navigation system that can gather the required information from real-time and online sources to suggest the routes that best match the users’ own preferences.

  15. The Trans-Visible Navigator: A See-Through Neuronavigation System Using Augmented Reality.

    Science.gov (United States)

    Watanabe, Eiju; Satoh, Makoto; Konno, Takehiko; Hirai, Masahiro; Yamaguchi, Takashi

    2016-03-01

    The neuronavigator has become indispensable for brain surgery and works in the manner of point-to-point navigation. Because the positional information is indicated on a personal computer (PC) monitor, surgeons are required to rotate the dimension of the magnetic resonance imaging/computed tomography scans to match the surgical field. In addition, they must frequently alternate their gaze between the surgical field and the PC monitor. To overcome these difficulties, we developed an augmented reality-based navigation system with whole-operation-room tracking. A tablet PC is used for visualization. The patient's head is captured by the back-face camera of the tablet. Three-dimensional images of intracranial structures are extracted from magnetic resonance imaging/computed tomography and are superimposed on the video image of the head. When viewed from various directions around the head, intracranial structures are displayed with corresponding angles as viewed from the camera direction, thus giving the surgeon the sensation of seeing through the head. Whole-operation-room tracking is realized using a VICON tracking system with 6 cameras. A phantom study showed a spatial resolution of about 1 mm. The present system was evaluated in 6 patients who underwent tumor resection surgery, and we showed that the system is useful for planning skin incisions as well as craniotomy and the localization of superficial tumors. The main advantage of the present system is that it achieves volumetric navigation in contrast to conventional point-to-point navigation. It extends augmented reality images directly onto real surgical images, thus helping the surgeon to integrate these 2 dimensions intuitively. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  16. Automated Navigation System based on Weapon-Target Assignment

    Directory of Open Access Journals (Sweden)

    Mohammad Khairudin

    2011-12-01

    Full Text Available Operating of weapon on the tank is mostly by manually. It is not desired performance for a critical operation. An automatic control system is required to operate the weapon with the target while maintaining the accuracy. In this paper has designed an automatic weapon control system using object image proccessing. Various an image processing methods used to improve the weapon accuracy to obtain the intended target. The method used in digital image processing is the Camshift motion tracking method. This method is compared with the Lucas Canade motion tracking method. This comparison is conducted to found more precise results between the two methods. Results of object image processing are used to control the direction of the weapon that towards the desired goal. The results show that the implementation of the Lucas Canade motion tracking method using fire simulation tools have been successful. The performance of the Lucas Canade motion tracking methods is better than the CamShift method. Using Lucas Canade method for weapon controller is accordance with the purposes.

  17. Evaluation of the Terminal Sequencing and Spacing System for Performance Based Navigation Arrivals

    Science.gov (United States)

    Thipphavong, Jane; Jung, Jaewoo; Swenson, Harry N.; Martin, Lynne; Lin, Melody; Nguyen, Jimmy

    2013-01-01

    NASA has developed the Terminal Sequencing and Spacing (TSS) system, a suite of advanced arrival management technologies combining timebased scheduling and controller precision spacing tools. TSS is a ground-based controller automation tool that facilitates sequencing and merging arrivals that have both current standard ATC routes and terminal Performance-Based Navigation (PBN) routes, especially during highly congested demand periods. In collaboration with the FAA and MITRE's Center for Advanced Aviation System Development (CAASD), TSS system performance was evaluated in human-in-the-loop (HITL) simulations with currently active controllers as participants. Traffic scenarios had mixed Area Navigation (RNAV) and Required Navigation Performance (RNP) equipage, where the more advanced RNP-equipped aircraft had preferential treatment with a shorter approach option. Simulation results indicate the TSS system achieved benefits by enabling PBN, while maintaining high throughput rates-10% above baseline demand levels. Flight path predictability improved, where path deviation was reduced by 2 NM on average and variance in the downwind leg length was 75% less. Arrivals flew more fuel-efficient descents for longer, spending an average of 39 seconds less in step-down level altitude segments. Self-reported controller workload was reduced, with statistically significant differences at the p less than 0.01 level. The RNP-equipped arrivals were also able to more frequently capitalize on the benefits of being "Best-Equipped, Best- Served" (BEBS), where less vectoring was needed and nearly all RNP approaches were conducted without interruption.

  18. Inertial Navigation System for India's Reusable Launch Vehicle-Technology Demonstrator (RLV-TD HEX) Mission

    Science.gov (United States)

    Umadevi, P.; Navas, A.; Karuturi, Kesavabrahmaji; Shukkoor, A. Abdul; Kumar, J. Krishna; Sreekumar, Sreejith; Basim, A. Mohammed

    2017-12-01

    This work presents the configuration of Inertial Navigation System (INS) used in India's Reusable Launch Vehicle-Technology Demonstrator (RLV-TD) Program. In view of the specific features and requirements of the RLV-TD, specific improvements and modifications were required in the INS. A new system was designed, realised and qualified meeting the mission requirements of RLV-TD, at the same time taking advantage of the flight heritage attained in INS through various Launch vehicle Missions of the country. The new system has additional redundancy in acceleration channel, in-built inclinometer based bias update scheme for acceleration channels and sign conventions as employed in an aircraft. Data acquisition in micro cycle periodicity (10 ms) was incorporated which was required to provide rate and attitude information at higher sampling rate for ascent phase control. Provision was incorporated for acquisition of rate and acceleration data with high resolution for aerodynamic characterisation and parameter estimation. GPS aided navigation scheme was incorporated to meet the stringent accuracy requirements of the mission. Navigation system configuration for RLV-TD, specific features incorporated to meet the mission requirements, various tests carried out and performance during RLV-TD flight are highlighted.

  19. A spatial registration method for navigation system combining O-arm with spinal surgery robot

    Science.gov (United States)

    Bai, H.; Song, G. L.; Zhao, Y. W.; Liu, X. Z.; Jiang, Y. X.

    2018-05-01

    The minimally invasive surgery in spinal surgery has become increasingly popular in recent years as it reduces the chances of complications during post-operation. However, the procedure of spinal surgery is complicated and the surgical vision of minimally invasive surgery is limited. In order to increase the quality of percutaneous pedicle screw placement, the O-arm that is a mobile intraoperative imaging system is used to assist surgery. The robot navigation system combined with O-arm is also increasing, with the extensive use of O-arm. One of the major problems in the surgical navigation system is to associate the patient space with the intra-operation image space. This study proposes a spatial registration method of spinal surgical robot navigation system, which uses the O-arm to scan a calibration phantom with metal calibration spheres. First, the metal artifacts were reduced in the CT slices and then the circles in the images based on the moments invariant could be identified. Further, the position of the calibration sphere in the image space was obtained. Moreover, the registration matrix is obtained based on the ICP algorithm. Finally, the position error is calculated to verify the feasibility and accuracy of the registration method.

  20. Navigating hybridity: investigating the dance between culture and values within the cuban national education system.

    Directory of Open Access Journals (Sweden)

    Erik Byker

    2013-12-01

    Full Text Available Hybridity is the dynamic relationship between local and global factors that push and pull on people and nations. Hybridity is deeply situated in socio-contextual factors, like cultural beliefs, education, and political systems, that aid and hinder a people’s navigation of globalized phenomena. Simply put, hybridity is how people and societies adapt to a changing world. This article examines the case of Cuba in response to hybridity. Specifically, the article’s purpose is to examine ways that the Cuban National Education System impacts how Cubans navigate the global march towards hybridity. The article reports on a focused ethnographic study of a week long education trip to Cuba during February 2013. The ethnography includes over 100 hours of data collection, including semi-structured interviews with 26 Cuban participants. The study uses Freire’s (1970 notion of “humanizing pedagogy” to analyze how the impact of the Cuban National Education System values in the context of Cuba and larger global context. The study found that three values in particular, amor, solidaridad, and conciencia de derechos y response, were deeply embedded in the Cuban National Education System and effect the way that Cubans navigate the complex hybridity that situates their island nation.

  1. Ballistic Aspects of Feasibility for Prospective Satellite Navigation Technologies

    Directory of Open Access Journals (Sweden)

    L. N. Lysenko

    2015-01-01

    Full Text Available When modeling the operating processes of ballistics and navigation support it is expedient to make decomposition of the general problem of coordinate-time and navigation support into the typical options of its engineering implementation.As the satellite navigation technologies the paper considers inter-satellite measurement and autonomous navigation mode of differential correction. It also assesses the possibility of their application to improve the accuracy of navigation determinations.Technologies using inter-satellite measurement tools such as GLONASS / GPS equipment, equipment of inter-satellite radio link, astro-optical space based devices are an independent class of navigation technologies.However, each of these options has both advantages and disadvantages that affect the eva luation of the appropriateness and feasibility of their use.The paper separately considers the problem of increasing survivability of space systems and conservation of ground control complex due to introduction of requirements to ensure the independent functioning of spacecraft and application of technologies of ballistics and navigation support, supposing to involve minimum means of automated ground control complex for these purposes.Currently, there is a completely developed theory of autonomous navigation based on astronomical positional gauges, which are used as onboard optical sensors of orientation and stabilization systems.To date, the differential navigation mode is, virtually, the only approach that can allow the olution of tasks in terms of increased accuracy, but with some restrictions.The implementation of differential mode of treatment is carried out through the creation of differential subsystems of the satellite navigation systems. These subsystems are usually divided into wide-range, regional and local ones.Analysis of ballistic aspects to implement discussed navigation technologies allowed us to identify constraints for improving accuracy to define

  2. Addressing the Influence of Space Weather on Airline Navigation

    Science.gov (United States)

    Sparks, Lawrence

    2012-01-01

    The advent of satellite-based augmentation systems has made it possible to navigate aircraft safely using radio signals emitted by global navigation satellite systems (GNSS) such as the Global Positioning System. As a signal propagates through the earth's ionosphere, it suffers delay that is proportional to the total electron content encountered along the raypath. Since the magnitude of this total electron content is strongly influenced by space weather, the safety and reliability of GNSS for airline navigation requires continual monitoring of the state of the ionosphere and calibration of ionospheric delay. This paper examines the impact of space weather on GNSS-based navigation and provides an overview of how the Wide Area Augmentation System protects its users from positioning error due to ionospheric disturbances

  3. Autonomous Navigation of the SSTI/Lewis Spacecraft Using the Global Positioning System (GPS)

    Science.gov (United States)

    Hart, R. C.; Long, A. C.; Lee, T.

    1997-01-01

    The National Aeronautics and Space Administration (NASA) Goddard Space Flight Center (GSFC) Flight Dynamics Division (FDD) is pursuing the application of Global Positioning System (GPS) technology to improve the accuracy and economy of spacecraft navigation. High-accuracy autonomous navigation algorithms are being flight qualified in conjunction with GSFC's GPS Attitude Determination Flyer (GADFLY) experiment on the Small Satellite Technology Initiative (SSTI) Lewis spacecraft, which is scheduled for launch in 1997. Preflight performance assessments indicate that these algorithms can provide a real-time total position accuracy of better than 10 meters (1 sigma) and velocity accuracy of better than 0.01 meter per second (1 sigma), with selective availability at typical levels. This accuracy is projected to improve to the 2-meter level if corrections to be provided by the GPS Wide Area Augmentation System (WAAS) are included.

  4. 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.

  5. A Wideband Autonomous Cognitive Radio Development and Prototyping System

    Science.gov (United States)

    2017-11-14

    three infrastructure modules (a Network Spectrum Analyzer, a Vector Signal Generator and a Rapid Printed Circuit Board (PCB) Fabrication Unit) and a...Antennas for Mobile Platforms”, 02/01/17-12/31/17 ($100K), Honeywell FM&T. 3. S. K. Jayaweera (Principal Investigator) and C. G. Christodoulou “Wideband...Signal Generator and a Rapid Printed Circuit Board (PCB) Fabrication Unit) and a Software Defined Radio (SDR) testbed made of several USRP SDR

  6. Linearization Technologies for Broadband Radio-Over-Fiber Transmission Systems

    Directory of Open Access Journals (Sweden)

    Xiupu Zhang

    2014-11-01

    Full Text Available Linearization technologies that can be used for linearizing RoF transmission are reviewed. Three main linearization methods, i.e. electrical analog linearization, optical linearization, and electrical digital linearization are presented and compared. Analog linearization can be achieved using analog predistortion circuits, and can be used for suppression of odd order nonlinear distortion components, such as third and fifth order. Optical linearization includes mixed-polarization, dual-wavelength, optical channelization and the others, implemented in optical domain, to suppress both even and odd order nonlinear distortion components, such as second and third order. Digital predistortion has been a widely used linearization method for RF power amplifiers. However, digital linearization that requires analog to digital converter is severely limited to hundreds of MHz bandwidth. Instead, analog and optical linearization provide broadband linearization with up to tens of GHz. Therefore, for broadband radio over fiber transmission that can be used for future broadband cloud radio access networks, analog and optical linearization are more appropriate than digital linearization. Generally speaking, both analog and optical linearization are able to improve spur-free dynamic range greater than 10 dB over tens of GHz. In order for current digital linearization to be used for broadband radio over fiber transmission, the reduced linearization complexity and increased linearization bandwidth are required. Moreover, some digital linearization methods in which the complexity can be reduced, such as Hammerstein type, may be more promising and require further investigation.

  7. Sea wind parameters retrieval using Y-configured Doppler navigation system data. Performance and accuracy

    Science.gov (United States)

    Khachaturian, A. B.; Nekrasov, A. V.; Bogachev, M. I.

    2018-05-01

    The authors report the results of the computer simulations of the performance and accuracy of the sea wind speed and direction retrieval. The analyzed measurements over the sea surface are made by the airborne microwave Doppler navigation system (DNS) with three Y-configured beams operated as a scatterometer enhancing its functionality. Single- and double-stage wind measurement procedures are proposed and recommendations for their implementation are described.

  8. Anti-Jam GPS Antennas for Wearable Dismounted Soldier Navigation Systems

    Science.gov (United States)

    2016-06-01

    GPS antenna, the Novatel GAJT-700M/ L CRPA is currently being considered, as shown in Fig. 6. Fig. 6 A basic 7-element CRPA (right) compared with a...ARL-TR-7670 ● JUNE 2016 US Army Research Laboratory Anti-Jam GPS Antennas for Wearable Dismounted Soldier Navigation Systems...longer needed. Do not return it to the originator. ARL-TR-7670 ● JUNE 2016 US Army Research Laboratory Anti-Jam GPS Antennas for

  9. 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

  10. Control and navigation system for a fixed-wing unmanned aerial vehicle

    Directory of Open Access Journals (Sweden)

    Ruiyong Zhai

    2014-02-01

    Full Text Available This paper presents a flight control and navigation system for a fixed-wing unmanned aerial vehicle (UAV with low-cost micro-electro-mechanical system (MEMS sensors. The system is designed under the inner loop and outer loop strategy. The trajectory tracking navigation loop is the outer loop of the attitude loop, while the attitude control loop is the outer loop of the stabilization loop. The proportional-integral-derivative (PID control was adopted for stabilization and attitude control. The three-dimensional (3D trajectory tracking control of a UAV could be approximately divided into lateral control and longitudinal control. The longitudinal control employs traditional linear PID feedback to achieve the desired altitude of the UAV, while the lateral control uses a non-linear control method to complete the desired trajectory. The non-linear controller can automatically adapt to ground velocity change, which is usually caused by gust disturbance, thus the UAV has good wind resistance characteristics. Flight tests and survey missions were carried out with our self-developed delta fixed-wing UAV and MEMS-based autopilot to confirm the effectiveness and practicality of the proposed navigation method.

  11. Development of automatic navigation measuring system using template-matching software in image guided neurosurgery

    International Nuclear Information System (INIS)

    Watanabe, Yohei; Hayashi, Yuichiro; Fujii, Masazumi; Wakabayashi, Toshihiko; Kimura, Miyuki; Tsuzaka, Masatoshi; Sugiura, Akihiro

    2010-01-01

    An image-guided neurosurgery and neuronavigation system based on magnetic resonance imaging has been used as an indispensable tool for resection of brain tumors. Therefore, accuracy of the neuronavigation system, provided by periodic quality assurance (QA), is essential for image-guided neurosurgery. Two types of accuracy index, fiducial registration error (FRE) and target registration error (TRE), have been used to evaluate navigation accuracy. FRE shows navigation accuracy on points that have been registered. On the other hand, TRE shows navigation accuracy on points such as tumor, skin, and fiducial markers. This study shows that TRE is more reliable than FRE. However, calculation of TRE is a time-consuming, subjective task. Software for QA was developed to compute TRE. This software calculates TRE automatically by an image processing technique, such as automatic template matching. TRE was calculated by the software and compared with the results obtained by manual calculation. Using the software made it possible to achieve a reliable QA system. (author)

  12. A Dynamic Precision Evaluation Method for the Star Sensor in the Stellar-Inertial Navigation System.

    Science.gov (United States)

    Lu, Jiazhen; Lei, Chaohua; Yang, Yanqiang

    2017-06-28

    Integrating the advantages of INS (inertial navigation system) and the star sensor, the stellar-inertial navigation system has been used for a wide variety of applications. The star sensor is a high-precision attitude measurement instrument; therefore, determining how to validate its accuracy is critical in guaranteeing its practical precision. The dynamic precision evaluation of the star sensor is more difficult than a static precision evaluation because of dynamic reference values and other impacts. This paper proposes a dynamic precision verification method of star sensor with the aid of inertial navigation device to realize real-time attitude accuracy measurement. Based on the gold-standard reference generated by the star simulator, the altitude and azimuth angle errors of the star sensor are calculated for evaluation criteria. With the goal of diminishing the impacts of factors such as the sensors' drift and devices, the innovative aspect of this method is to employ static accuracy for comparison. If the dynamic results are as good as the static results, which have accuracy comparable to the single star sensor's precision, the practical precision of the star sensor is sufficiently high to meet the requirements of the system specification. The experiments demonstrate the feasibility and effectiveness of the proposed method.

  13. Radio emission from a helical electron beam-plasma system in a twisted magnetic field

    International Nuclear Information System (INIS)

    Krishan, V.

    1982-01-01

    The excitation of electromagnetic radiation near the harmonics of electron plasma frequency from a helical electron beam travelling parallel to a helical magnetic field through a stationary inhomogeneous plasma is studied. The motivation behind this study is to explain the observed characteristics of the type III solar radio bursts and thus to predict the nature of the plasma system responsible for the generation of these radio bursts. (author)

  14. Effect of radio-detoxified endotoxin on the liver microsomal drug metabolizing enzyme system in rats

    International Nuclear Information System (INIS)

    Bertok, L.; Szeberenyi, S.

    1983-01-01

    E. coli endotoxin (LPS) depresses the hepatic microsomal mono-oxygenase activity. Radio-detoxified LPS (TOLERIN: 60 Co irradiated endotoxin preparation) decreases this biotransforming activity to a smaller extent. Phenobarbital, an inducer of this mono-oxygenase system, failed to induce in LPS-treated animals. In radio-detoxified LPS-treated rats, phenobarbital induced the mono-oxygenase and almost fully restored the biotransformation

  15. Interference coupling analysis based on a hybrid method: application to a radio telescope system

    Science.gov (United States)

    Xu, Qing-Lin; Qiu, Yang; Tian, Jin; Liu, Qi

    2018-02-01

    Working in a way that passively receives electromagnetic radiation from a celestial body, a radio telescope can be easily disturbed by external radio frequency interference as well as electromagnetic interference generated by electric and electronic components operating at the telescope site. A quantitative analysis of these interferences must be taken into account carefully for further electromagnetic protection of the radio telescope. In this paper, based on electromagnetic topology theory, a hybrid method that combines the Baum-Liu-Tesche (BLT) equation and transfer function is proposed. In this method, the coupling path of the radio telescope is divided into strong coupling and weak coupling sub-paths, and the coupling intensity criterion is proposed by analyzing the conditions in which the BLT equation simplifies to a transfer function. According to the coupling intensity criterion, the topological model of a typical radio telescope system is established. The proposed method is used to solve the interference response of the radio telescope system by analyzing subsystems with different coupling modes separately and then integrating the responses of the subsystems as the response of the entire system. The validity of the proposed method is verified numerically. The results indicate that the proposed method, compared with the direct solving method, reduces the difficulty and improves the efficiency of interference prediction.

  16. Application of Real-Time 3D Navigation System in CT-Guided Percutaneous Interventional Procedures: A Feasibility Study

    Directory of Open Access Journals (Sweden)

    Priya Bhattacharji

    2017-01-01

    Full Text Available Introduction. To evaluate the accuracy of a quantitative 3D navigation system for CT-guided interventional procedures in a two-part study. Materials and Methods. Twenty-two procedures were performed in abdominal and thoracic phantoms. Accuracies of the 3D anatomy map registration and navigation were evaluated. Time used for the navigated procedures was recorded. In the IRB approved clinical evaluation, 21 patients scheduled for CT-guided thoracic and hepatic biopsy and ablations were recruited. CT-guided procedures were performed without following the 3D navigation display. Accuracy of navigation as well as workflow fitness of the system was evaluated. Results. In phantoms, the average 3D anatomy map registration error was 1.79 mm. The average navigated needle placement accuracy for one-pass and two-pass procedures, respectively, was 2.0±0.7 mm and 2.8±1.1 mm in the liver and 2.7±1.7 mm and 3.0±1.4 mm in the lung. The average accuracy of the 3D navigation system in human subjects was 4.6 mm ± 3.1 for all procedures. The system fits the existing workflow of CT-guided interventions with minimum impact. Conclusion. A 3D navigation system can be performed along the existing workflow and has the potential to navigate precision needle placement in CT-guided interventional procedures.

  17. 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.

  18. Design and Implementation of a Fully Autonomous UAV's Navigator Based on Omni-directional Vision System

    Directory of Open Access Journals (Sweden)

    Seyed Mohammadreza Kasaei

    2011-12-01

    Full Text Available Unmanned Aerial Vehicles (UAVs are the subject of an increasing interest in many applications . UAVs are seeing more widespread use in military, scenic, and civilian sectors in recent years. Autonomy is one of the major advantages of these vehicles. It is then necessary to develop particular sensor in order to provide efficient navigation functions. The helicopter has been stabilized with visual information through the control loop. Omni directional vision can be a useful sensor for this propose. It can be used as the only sensor or as complementary sensor. In this paper , we propose a novel method for path planning on an UAV based on electrical potential .We are using an omni directional vision system for navigating and path planning.

  19. Indoor navigation by people with visual impairment using a digital sign system.

    Directory of Open Access Journals (Sweden)

    Gordon E Legge

    Full Text Available There is a need for adaptive technology to enhance indoor wayfinding by visually-impaired people. To address this need, we have developed and tested a Digital Sign System. The hardware and software consist of digitally-encoded signs widely distributed throughout a building, a handheld sign-reader based on an infrared camera, image-processing software, and a talking digital map running on a mobile device. Four groups of subjects-blind, low vision, blindfolded sighted, and normally sighted controls-were evaluated on three navigation tasks. The results demonstrate that the technology can be used reliably in retrieving information from the signs during active mobility, in finding nearby points of interest, and following routes in a building from a starting location to a destination. The visually impaired subjects accurately and independently completed the navigation tasks, but took substantially longer than normally sighted controls. This fully functional prototype system demonstrates the feasibility of technology enabling independent indoor navigation by people with visual impairment.

  20. Indoor navigation by people with visual impairment using a digital sign system.

    Science.gov (United States)

    Legge, Gordon E; Beckmann, Paul J; Tjan, Bosco S; Havey, Gary; Kramer, Kevin; Rolkosky, David; Gage, Rachel; Chen, Muzi; Puchakayala, Sravan; Rangarajan, Aravindhan

    2013-01-01

    There is a need for adaptive technology to enhance indoor wayfinding by visually-impaired people. To address this need, we have developed and tested a Digital Sign System. The hardware and software consist of digitally-encoded signs widely distributed throughout a building, a handheld sign-reader based on an infrared camera, image-processing software, and a talking digital map running on a mobile device. Four groups of subjects-blind, low vision, blindfolded sighted, and normally sighted controls-were evaluated on three navigation tasks. The results demonstrate that the technology can be used reliably in retrieving information from the signs during active mobility, in finding nearby points of interest, and following routes in a building from a starting location to a destination. The visually impaired subjects accurately and independently completed the navigation tasks, but took substantially longer than normally sighted controls. This fully functional prototype system demonstrates the feasibility of technology enabling independent indoor navigation by people with visual impairment.

  1. 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.

  2. 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.

  3. A New Electromagnetic Navigation System for Pedicle Screws Placement: A Human Cadaver Study at the Lumbar Spine.

    Directory of Open Access Journals (Sweden)

    Patrick Hahn

    Full Text Available Technical developments for improving the safety and accuracy of pedicle screw placement play an increasingly important role in spine surgery. In addition to the standard techniques of free-hand placement and fluoroscopic navigation, the rate of complications is reduced by 3D fluoroscopy, cone-beam CT, intraoperative CT/MRI, and various other navigation techniques. Another important aspect that should be emphasized is the reduction of intraoperative radiation exposure for personnel and patient. The aim of this study was to investigate the accuracy of a new navigation system for the spine based on an electromagnetic field.Twenty pedicle screws were placed in the lumbar spine of human cadavers using EMF navigation. Navigation was based on data from a preoperative thin-slice CT scan. The cadavers were positioned on a special field generator and the system was matched using a patient tracker on the spinous process. Navigation was conducted using especially developed instruments that can be tracked in the electromagnetic field. Another thin-slice CT scan was made postoperatively to assess the result. The evaluation included the position of the screws in the direction of trajectory and any injury to the surrounding cortical bone. The results were classified in 5 groups: grade 1: ideal screw position in the center of the pedicle with no cortical bone injury; grade 2: acceptable screw position, cortical bone injury with cortical penetration ≤ 2 mm; grade 3: cortical bone injury with cortical penetration 2,1-4 mm, grad 4: cortical bone injury with cortical penetration 4,1-6 mm, grade 5: cortical bone injury with cortical penetration >6 mm.The initial evaluation of the system showed good accuracy for the lumbar spine (65% grade 1, 20% grade 2, 15% grade 3, 0% grade 4, 0% grade 5. A comparison of the initial results with other navigation techniques in literature (CT navigation, 2D fluoroscopic navigation shows that the accuracy of this system is

  4. 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.

  5. 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

  6. 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

  7. SeSaMoNet 2.0: Improving a Navigation System for Visually Impaired People

    Science.gov (United States)

    Ceipidor, Ugo Biader; Medaglia, Carlo Maria; Sciarretta, Eliseo

    The authors present the improvements obtained during the work done for the last installation of SeSaMoNet, a navigation system for blind people. First the mobility issues of visually impaired people are shown together with strategies to solve them. Then an overview of the system and of its main elements is given. Afterward, the reasons which brought to a re-design are explained and finally the main features of the last system revision for the application are presented and compared to the previous one.

  8. Ground-Based Global Navigation Satellite System (GNSS) GPS Broadcast Ephemeris Data (daily files) from NASA CDDIS

    Data.gov (United States)

    National Aeronautics and Space Administration — This dataset consists of ground-based Global Navigation Satellite System (GNSS) GPS Broadcast Ephemeris Data (daily files) from the NASA Crustal Dynamics Data...

  9. Ground-Based Global Navigation Satellite System Mixed Broadcast Ephemeris Data (sub-hourly files) from NASA CDDIS

    Data.gov (United States)

    National Aeronautics and Space Administration — This dataset consists of ground-based Global Navigation Satellite System (GNSS) Mixed Broadcast Ephemeris Data (sub-hourly files) from the NASA Crustal Dynamics Data...

  10. Design of radio frequency power amplifiers for cellular phones and base stations in modern mobile communication systems

    OpenAIRE

    Wu, Lei

    2009-01-01

    The mobile radio communication has begun with Guglielmo Marconi's and Alexander Popov's experiments with ship-to-shore communication in the 1890's. Land mobile radio telephone systems have been used since the Detroit City Police Department installed the first wireless communication system in 1921. Since that time, radio systems have become more and more important for both voice and data communication. The modern mobile communication systems are mainly designed in high frequency ranges due...

  11. Abstract Radio Resource Management Framework for System Level Simulations in LTE-A Systems

    DEFF Research Database (Denmark)

    Fotiadis, Panagiotis; Viering, Ingo; Zanier, Paolo

    2014-01-01

    This paper provides a simple mathematical model of different packet scheduling policies in Long Term Evolution- Advanced (LTE-A) systems, by investigating the performance of Proportional Fair (PF) and the generalized cross-Component Carrier scheduler from a theoretical perspective. For that purpose......, an abstract Radio Resource Management (RRM) framework has been developed and tested for different ratios of users with Carrier Aggregation (CA) capabilities. The conducted system level simulations confirm that the proposed model can satisfactorily capture the main properties of the aforementioned scheduling...

  12. A Google Glass navigation system for ultrasound and fluorescence dual-mode image-guided surgery

    Science.gov (United States)

    Zhang, Zeshu; Pei, Jing; Wang, Dong; Hu, Chuanzhen; Ye, Jian; Gan, Qi; Liu, Peng; Yue, Jian; Wang, Benzhong; Shao, Pengfei; Povoski, Stephen P.; Martin, Edward W.; Yilmaz, Alper; Tweedle, Michael F.; Xu, Ronald X.

    2016-03-01

    Surgical resection remains the primary curative intervention for cancer treatment. However, the occurrence of a residual tumor after resection is very common, leading to the recurrence of the disease and the need for re-resection. We develop a surgical Google Glass navigation system that combines near infrared fluorescent imaging and ultrasonography for intraoperative detection of sites of tumor and assessment of surgical resection boundaries, well as for guiding sentinel lymph node (SLN) mapping and biopsy. The system consists of a monochromatic CCD camera, a computer, a Google Glass wearable headset, an ultrasonic machine and an array of LED light sources. All the above components, except the Google Glass, are connected to a host computer by a USB or HDMI port. Wireless connection is established between the glass and the host computer for image acquisition and data transport tasks. A control program is written in C++ to call OpenCV functions for image calibration, processing and display. The technical feasibility of the system is tested in both tumor simulating phantoms and in a human subject. When the system is used for simulated phantom resection tasks, the tumor boundaries, invisible to the naked eye, can be clearly visualized with the surgical Google Glass navigation system. This system has also been used in an IRB approved protocol in a single patient during SLN mapping and biopsy in the First Affiliated Hospital of Anhui Medical University, demonstrating the ability to successfully localize and resect all apparent SLNs. In summary, our tumor simulating phantom and human subject studies have demonstrated the technical feasibility of successfully using the proposed goggle navigation system during cancer surgery.

  13. 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

  14. A biologically inspired meta-control navigation system for the Psikharpax rat robot

    International Nuclear Information System (INIS)

    Caluwaerts, K; Staffa, M; N’Guyen, S; Grand, C; Dollé, L; Favre-Félix, A; Girard, B; Khamassi, M

    2012-01-01

    A biologically inspired navigation system for the mobile rat-like robot named Psikharpax is presented, allowing for self-localization and autonomous navigation in an initially unknown environment. The ability of parts of the model (e.g. the strategy selection mechanism) to reproduce rat behavioral data in various maze tasks has been validated before in simulations. But the capacity of the model to work on a real robot platform had not been tested. This paper presents our work on the implementation on the Psikharpax robot of two independent navigation strategies (a place-based planning strategy and a cue-guided taxon strategy) and a strategy selection meta-controller. We show how our robot can memorize which was the optimal strategy in each situation, by means of a reinforcement learning algorithm. Moreover, a context detector enables the controller to quickly adapt to changes in the environment—recognized as new contexts—and to restore previously acquired strategy preferences when a previously experienced context is recognized. This produces adaptivity closer to rat behavioral performance and constitutes a computational proposition of the role of the rat prefrontal cortex in strategy shifting. Moreover, such a brain-inspired meta-controller may provide an advancement for learning architectures in robotics. (paper)

  15. 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.

  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. LOFAR discovery of a double radio halo system in Abell 1758 and radio/X-ray study of the cluster pair

    Science.gov (United States)

    Botteon, A.; Shimwell, T. W.; Bonafede, A.; Dallacasa, D.; Brunetti, G.; Mandal, S.; van Weeren, R. J.; Brüggen, M.; Cassano, R.; de Gasperin, F.; Hoang, D. N.; Hoeft, M.; Röttgering, H. J. A.; Savini, F.; White, G. J.; Wilber, A.; Venturi, T.

    2018-05-01

    Radio halos and radio relics are diffuse synchrotron sources that extend over Mpc-scales and are found in a number of merger galaxy clusters. They are believed to form as a consequence of the energy that is dissipated by turbulence and shocks in the intra-cluster medium (ICM). However, the precise physical processes that generate these steep synchrotron spectrum sources are still poorly constrained. We present a new LOFAR observation of the double galaxy cluster Abell 1758. This system is composed of A1758N, a massive cluster hosting a known giant radio halo, and A1758S, which is a less massive cluster whose diffuse radio emission is confirmed here for the first time. Our observations have revealed a radio halo and a candidate radio relic in A1758S, and a suggestion of emission along the bridge connecting the two systems which deserves confirmation. We combined the LOFAR data with archival VLA and GMRT observations to constrain the spectral properties of the diffuse emission. We also analyzed a deep archival Chandra observation and used this to provide evidence that A1758N and A1758S are in a pre-merger phase. The ICM temperature across the bridge that connects the two systems shows a jump which might indicate the presence of a transversal shock generated in the initial stage of the merger.

  18. Doppler Navigation System with a Non-Stabilized Antenna as a Sea-Surface Wind Sensor.

    Science.gov (United States)

    Nekrasov, Alexey; Khachaturian, Alena; Veremyev, Vladimir; Bogachev, Mikhail

    2017-06-09

    We propose a concept of the utilization of an aircraft Doppler Navigation System (DNS) as a sea-surface wind sensor complementary to its normal functionality. The DNS with an antenna, which is non-stabilized physically to the local horizontal with x -configured beams, is considered. We consider the wind measurements by the DNS configured in the multi-beam scatterometer mode for a rectilinear flight scenario. The system feasibility and the efficiency of the proposed wind algorithm retrieval are supported by computer simulations. Finally, the associated limitations of the proposed approach are considered.

  19. Data Analysis of the TK-1G Sounding Rocket Installed with a Satellite Navigation System

    Directory of Open Access Journals (Sweden)

    Lesong Zhou

    2017-10-01

    Full Text Available This article gives an in-depth analysis of the experimental data of the TK-1G sounding rocket installed with the satellite navigation system. It turns out that the data acquisition rate of the rocket sonde is high, making the collection of complete trajectory and meteorological data possible. By comparing the rocket sonde measurements with those obtained by virtue of other methods, we find that the rocket sonde can be relatively precise in measuring atmospheric parameters within the scope of 20–60 km above the ground. This establishes the fact that the TK-1G sounding rocket system is effective in detecting near-space atmospheric environment.

  20. Discovery of radio emission from the symbiotic X-ray binary system GX 1+4

    Science.gov (United States)

    van den Eijnden, J.; Degenaar, N.; Russell, T. D.; Miller-Jones, J. C. A.; Wijnands, R.; Miller, J. M.; King, A. L.; Rupen, M. P.

    2018-02-01

    We report the discovery of radio emission from the accreting X-ray pulsar and symbiotic X-ray binary GX 1+4 with the Karl G. Jansky Very Large Array. This is the first radio detection of such a system, wherein a strongly magnetized neutron star accretes from the stellar wind of an M-type giant companion. We measure a 9 GHz radio flux density of 105.3 ± 7.3 μJy, but cannot place meaningful constraints on the spectral index due to a limited frequency range. We consider several emission mechanisms that could be responsible for the observed radio source. We conclude that the observed properties are consistent with shocks in the interaction of the accretion flow with the magnetosphere, a synchrotron-emitting jet, or a propeller-driven outflow. The stellar wind from the companion is unlikely to be the origin of the radio emission. If the detected radio emission originates from a jet, it would show that strong magnetic fields (≥1012 G) do not necessarily suppress jet formation.

  1. Analysis on Calibration and Uncertainty for TD-LTE Radio Test System

    Directory of Open Access Journals (Sweden)

    Zhang Weipeng

    2014-06-01

    Full Text Available TD-LTE base station radio test system measures radio signal with a required accuracy, so calibration need to be done for transmission path between base station and measurement instruments before test. Considering Transmitter OFF Power measurement within OFF period, modulated signal generator and spectrum analyzer inside test system is used for calibration, to get accurate transmission parameters of the paths, and to reduce test cost without more instruments. The paper describes the uncertainty of test system, analyzes uncertainty contribution of interface mismatch, calculates uncertainty for Transmitter OFF Power measurement, uncertainty is 1.193 dB, within the requirement of 3GPP specification.

  2. Modelling and Experiment Based on a Navigation System for a Cranio-Maxillofacial Surgical Robot

    Science.gov (United States)

    Duan, Xingguang; Gao, Liang; Li, Jianxi; Li, Haoyuan; Guo, Yanjun

    2018-01-01

    In view of the characteristics of high risk and high accuracy in cranio-maxillofacial surgery, we present a novel surgical robot system that can be used in a variety of surgeries. The surgical robot system can assist surgeons in completing biopsy of skull base lesions, radiofrequency thermocoagulation of the trigeminal ganglion, and radioactive particle implantation of skull base malignant tumors. This paper focuses on modelling and experimental analyses of the robot system based on navigation technology. Firstly, the transformation relationship between the subsystems is realized based on the quaternion and the iterative closest point registration algorithm. The hand-eye coordination model based on optical navigation is established to control the end effector of the robot moving to the target position along the planning path. The closed-loop control method, “kinematics + optics” hybrid motion control method, is presented to improve the positioning accuracy of the system. Secondly, the accuracy of the system model was tested by model experiments. And the feasibility of the closed-loop control method was verified by comparing the positioning accuracy before and after the application of the method. Finally, the skull model experiments were performed to evaluate the function of the surgical robot system. The results validate its feasibility and are consistent with the preoperative surgical planning. PMID:29599948

  3. 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.

  4. 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.

  5. Modelling and Experiment Based on a Navigation System for a Cranio-Maxillofacial Surgical Robot

    Directory of Open Access Journals (Sweden)

    Xingguang Duan

    2018-01-01

    Full Text Available In view of the characteristics of high risk and high accuracy in cranio-maxillofacial surgery, we present a novel surgical robot system that can be used in a variety of surgeries. The surgical robot system can assist surgeons in completing biopsy of skull base lesions, radiofrequency thermocoagulation of the trigeminal ganglion, and radioactive particle implantation of skull base malignant tumors. This paper focuses on modelling and experimental analyses of the robot system based on navigation technology. Firstly, the transformation relationship between the subsystems is realized based on the quaternion and the iterative closest point registration algorithm. The hand-eye coordination model based on optical navigation is established to control the end effector of the robot moving to the target position along the planning path. The closed-loop control method, “kinematics + optics” hybrid motion control method, is presented to improve the positioning accuracy of the system. Secondly, the accuracy of the system model was tested by model experiments. And the feasibility of the closed-loop control method was verified by comparing the positioning accuracy before and after the application of the method. Finally, the skull model experiments were performed to evaluate the function of the surgical robot system. The results validate its feasibility and are consistent with the preoperative surgical planning.

  6. Error Analysis and Calibration Method of a Multiple Field-of-View Navigation System.

    Science.gov (United States)

    Shi, Shuai; Zhao, Kaichun; You, Zheng; Ouyang, Chenguang; Cao, Yongkui; Wang, Zhenzhou

    2017-03-22

    The Multiple Field-of-view Navigation System (MFNS) is a spacecraft subsystem built to realize the autonomous navigation of the Spacecraft Inside Tiangong Space Station. This paper introduces the basics of the MFNS, including its architecture, mathematical model and analysis, and numerical simulation of system errors. According to the performance requirement of the MFNS, the calibration of both intrinsic and extrinsic parameters of the system is assumed to be essential and pivotal. Hence, a novel method based on the geometrical constraints in object space, called checkerboard-fixed post-processing calibration (CPC), is proposed to solve the problem of simultaneously obtaining the intrinsic parameters of the cameras integrated in the MFNS and the transformation between the MFNS coordinate and the cameras' coordinates. This method utilizes a two-axis turntable and a prior alignment of the coordinates is needed. Theoretical derivation and practical operation of the CPC method are introduced. The calibration experiment results of the MFNS indicate that the extrinsic parameter accuracy of the CPC reaches 0.1° for each Euler angle and 0.6 mm for each position vector component (1σ). A navigation experiment verifies the calibration result and the performance of the MFNS. The MFNS is found to work properly, and the accuracy of the position vector components and Euler angle reaches 1.82 mm and 0.17° (1σ) respectively. The basic mechanism of the MFNS may be utilized as a reference for the design and analysis of multiple-camera systems. Moreover, the calibration method proposed has practical value for its convenience for use and potential for integration into a toolkit.

  7. Developing and Evaluating a Virtual Reality-Based Navigation System for Pre-Sale Housing Sales

    Directory of Open Access Journals (Sweden)

    Yi-Kai Juan

    2018-06-01

    Full Text Available Virtual reality (VR technologies have advanced rapidly in the past few years, and many industries have adopted these cutting-edge technologies for diverse applications to improve their industrial competitiveness. VR has also received considerable recognition in the architecture, engineering, and construction industries, because it can potentially reduce project costs, delivery time, and quality risks, by allowing users to experience unbuilt spaces before breaking ground, resolving construction conflicts virtually, and reviewing complex details in immersive environments. In the real estate market, VR can also play an important role in affecting buyers’ housing purchasing decisions, especially for housing markets in Asia, where the pre-sale system is extremely common. Applying VR to the pre-sale housing system is promising, because the concept of pre-sale refers to a strategy adopted by developers that sell housing through agreements on residential units that have not been constructed yet, and VR at this stage could be a useful tool for visual communication in a true-to-scale environment. However, does VR really benefit sales in the housing market? Can clients accept using VR, instead of using traditional materials (i.e., paper-based images and physical models, to navigate and experience housing projects? The objective of this study is to develop a VR-based navigation system for a pre-sale housing project in Taiwan. We invited 30 potential clients to test the system and explore the implications of using it for project navigation. The results reveal that VR enhances the understandings of a project (perceived usefulness and increases clients’ intention to purchase, while the operation of VR (perceived ease-of-use is still the major challenge to affect clients’ satisfaction and the developer’s acceptance with respect to applying it to future housing sales.

  8. Model-based software engineering for an optical navigation system for spacecraft

    Science.gov (United States)

    Franz, T.; Lüdtke, D.; Maibaum, O.; Gerndt, A.

    2018-06-01

    The project Autonomous Terrain-based Optical Navigation (ATON) at the German Aerospace Center (DLR) is developing an optical navigation system for future landing missions on celestial bodies such as the moon or asteroids. Image data obtained by optical sensors can be used for autonomous determination of the spacecraft's position and attitude. Camera-in-the-loop experiments in the Testbed for Robotic Optical Navigation (TRON) laboratory and flight campaigns with unmanned aerial vehicle (UAV) are performed to gather flight data for further development and to test the system in a closed-loop scenario. The software modules are executed in the C++ Tasking Framework that provides the means to concurrently run the modules in separated tasks, send messages between tasks, and schedule task execution based on events. Since the project is developed in collaboration with several institutes in different domains at DLR, clearly defined and well-documented interfaces are necessary. Preventing misconceptions caused by differences between various development philosophies and standards turned out to be challenging. After the first development cycles with manual Interface Control Documents (ICD) and manual implementation of the complex interactions between modules, we switched to a model-based approach. The ATON model covers a graphical description of the modules, their parameters and communication patterns. Type and consistency checks on this formal level help to reduce errors in the system. The model enables the generation of interfaces and unified data types as well as their documentation. Furthermore, the C++ code for the exchange of data between the modules and the scheduling of the software tasks is created automatically. With this approach, changing the data flow in the system or adding additional components (e.g., a second camera) have become trivial.

  9. Model-based software engineering for an optical navigation system for spacecraft

    Science.gov (United States)

    Franz, T.; Lüdtke, D.; Maibaum, O.; Gerndt, A.

    2017-09-01

    The project Autonomous Terrain-based Optical Navigation (ATON) at the German Aerospace Center (DLR) is developing an optical navigation system for future landing missions on celestial bodies such as the moon or asteroids. Image data obtained by optical sensors can be used for autonomous determination of the spacecraft's position and attitude. Camera-in-the-loop experiments in the Testbed for Robotic Optical Navigation (TRON) laboratory and flight campaigns with unmanned aerial vehicle (UAV) are performed to gather flight data for further development and to test the system in a closed-loop scenario. The software modules are executed in the C++ Tasking Framework that provides the means to concurrently run the modules in separated tasks, send messages between tasks, and schedule task execution based on events. Since the project is developed in collaboration with several institutes in different domains at DLR, clearly defined and well-documented interfaces are necessary. Preventing misconceptions caused by differences between various development philosophies and standards turned out to be challenging. After the first development cycles with manual Interface Control Documents (ICD) and manual implementation of the complex interactions between modules, we switched to a model-based approach. The ATON model covers a graphical description of the modules, their parameters and communication patterns. Type and consistency checks on this formal level help to reduce errors in the system. The model enables the generation of interfaces and unified data types as well as their documentation. Furthermore, the C++ code for the exchange of data between the modules and the scheduling of the software tasks is created automatically. With this approach, changing the data flow in the system or adding additional components (e.g., a second camera) have become trivial.

  10. A Study on the Radio Coverage in Underground Stations of the New Copenhagen Metro System

    DEFF Research Database (Denmark)

    Millan, Maria del Carmen de la O; Sørensen, Troels Bundgaard; Mikkelsen, Niels Michael

    2013-01-01

    In connection with the extension of the Copenhagen Metro system, architects and wireless operators met early in the design phase to plan the radio coverage inside the public areas of the metro transport system. Based on common best practice, an initial design for the antenna installations......, and hence radio coverage, was proposed for a distributed antenna system in each of two distinctly different types of underground stations. In this paper, we describe the considerations for the design, and specifically the modelling and analysis of the underground stations by way of a commercial ray......-tracing tool. Radio coverage results are given for different designs, including different number and types of antennas, their configuration and placement, as well as the dependency on frequency and construction materials and presence of trains on the station platforms. In a practical case like this...

  11. 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.

  12. 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.

  13. Pipeline control support system, 'pipe navigation'; Kanro kanri shien system 'kannabi'

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-01-10

    'Pipe navigation' is a pipeline control support system which employs GIS/GPS (geographic information system/global positioning system) technology in controlling information of water pipeline and incidental facilities, using a pen note/personal computer as the operating base. These pen computers can be carried to the spot and used in displaying pipeline/incidental equipment and retrieving related information. The main features as follows:(1) Memo preparation is possible at an arbitrary place with handwriting ease. The memo data so prepared can be taken in other terminals and shared.(2) Communication with remote places is possible by transmitting drawings, prepared memo data, etc., as in facsimile (3) Confirmation of the present position and navigation are possible (GPS function), demonstrating power in a restoration work at the time of earthquake for example.(4) Inputting and maintenance of each facility information are possible through the data input support function even by general users easily. (translated by NEDO)

  14. Three-Dimensional Implant Positioning with a Piezosurgery Implant Site Preparation Technique and an Intraoral Surgical Navigation System: Case Report.

    Science.gov (United States)

    Pellegrino, Gerardo; Taraschi, Valerio; Vercellotti, Tomaso; Ben-Nissan, Besim; Marchetti, Claudio

    This case report describes new implant site preparation techniques joining the benefits of using an intraoral navigation system to optimize three-dimensional implant site positioning in combination with an ultrasonic osteotomy. A report of five patients is presented, and the implant positions as planned in the navigation software with the postoperative scan image were compared. The preliminary results are useful, although further clinical studies with larger populations are needed to confirm these findings.

  15. Blind MuseumTourer: A System for Self-Guided Tours in Museums and Blind Indoor Navigation

    OpenAIRE

    Apostolos Meliones; Demetrios Sampson

    2018-01-01

    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 curr...

  16. An Aerial-Ground Robotic System for Navigation and Obstacle Mapping in Large Outdoor Areas

    Directory of Open Access Journals (Sweden)

    David Zapata

    2013-01-01

    Full Text Available There are many outdoor robotic applications where a robot must reach a goal position or explore an area without previous knowledge of the environment around it. Additionally, other applications (like path planning require the use of known maps or previous information of the environment. This work presents a system composed by a terrestrial and an aerial robot that cooperate and share sensor information in order to address those requirements. The ground robot is able to navigate in an unknown large environment aided by visual feedback from a camera on board the aerial robot. At the same time, the obstacles are mapped in real-time by putting together the information from the camera and the positioning system of the ground robot. A set of experiments were carried out with the purpose of verifying the system applicability. The experiments were performed in a simulation environment and outdoor with a medium-sized ground robot and a mini quad-rotor. The proposed robotic system shows outstanding results in simultaneous navigation and mapping applications in large outdoor environments.

  17. 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.

  18. A Novel Augmented Reality-Based Navigation System in Perforator Flap Transplantation - A Feasibility Study.

    Science.gov (United States)

    Jiang, Taoran; Zhu, Ming; Zan, Tao; Gu, Bin; Li, Qingfeng

    2017-08-01

    In perforator flap transplantation, dissection of the perforator is an important but difficult procedure because of the high variability in vascular anatomy. Preoperative imaging techniques could provide substantial information about vascular anatomy; however, it cannot provide direct guidance for surgeons during the operation. In this study, a navigation system (NS) was established to overlie a vascular map on surgical sites to further provide a direct guide for perforator flap transplantation. The NS was established based on computed tomographic angiography and augmented reality techniques. A virtual vascular map was reconstructed according to computed tomographic angiography data and projected onto real patient images using ARToolKit software. Additionally, a screw-fixation marker holder was created to facilitate registration. With the use of a tracking and display system, we conducted the NS on an animal model and measured the system error on a rapid prototyping model. The NS assistance allowed for correct identification, as well as a safe and precise dissection of the perforator. The mean value of the system error was determined to be 3.474 ± 1.546 mm. Augmented reality-based NS can provide precise navigation information by directly displaying a 3-dimensional individual anatomical virtual model onto the operative field in real time. It will allow rapid identification and safe dissection of a perforator in free flap transplantation surgery.

  19. A Navigation System for the Visually Impaired: A Fusion of Vision and Depth Sensor

    Science.gov (United States)

    Kanwal, Nadia; Bostanci, Erkan; Currie, Keith; Clark, Adrian F.

    2015-01-01

    For a number of years, scientists have been trying to develop aids that can make visually impaired people more independent and aware of their surroundings. Computer-based automatic navigation tools are one example of this, motivated by the increasing miniaturization of electronics and the improvement in processing power and sensing capabilities. This paper presents a complete navigation system based on low cost and physically unobtrusive sensors such as a camera and an infrared sensor. The system is based around corners and depth values from Kinect's infrared sensor. Obstacles are found in images from a camera using corner detection, while input from the depth sensor provides the corresponding distance. The combination is both efficient and robust. The system not only identifies hurdles but also suggests a safe path (if available) to the left or right side and tells the user to stop, move left, or move right. The system has been tested in real time by both blindfolded and blind people at different indoor and outdoor locations, demonstrating that it operates adequately. PMID:27057135

  20. 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

  1. An Application of UAV Attitude Estimation Using a Low-Cost Inertial Navigation System

    Science.gov (United States)

    Eure, Kenneth W.; Quach, Cuong Chi; Vazquez, Sixto L.; Hogge, Edward F.; Hill, Boyd L.

    2013-01-01

    Unmanned Aerial Vehicles (UAV) are playing an increasing role in aviation. Various methods exist for the computation of UAV attitude based on low cost microelectromechanical systems (MEMS) and Global Positioning System (GPS) receivers. There has been a recent increase in UAV autonomy as sensors are becoming more compact and onboard processing power has increased significantly. Correct UAV attitude estimation will play a critical role in navigation and separation assurance as UAVs share airspace with civil air traffic. This paper describes attitude estimation derived by post-processing data from a small low cost Inertial Navigation System (INS) recorded during the flight of a subscale commercial off the shelf (COTS) UAV. Two discrete time attitude estimation schemes are presented here in detail. The first is an adaptation of the Kalman Filter to accommodate nonlinear systems, the Extended Kalman Filter (EKF). The EKF returns quaternion estimates of the UAV attitude based on MEMS gyro, magnetometer, accelerometer, and pitot tube inputs. The second scheme is the complementary filter which is a simpler algorithm that splits the sensor frequency spectrum based on noise characteristics. The necessity to correct both filters for gravity measurement errors during turning maneuvers is demonstrated. It is shown that the proposed algorithms may be used to estimate UAV attitude. The effects of vibration on sensor measurements are discussed. Heuristic tuning comments pertaining to sensor filtering and gain selection to achieve acceptable performance during flight are given. Comparisons of attitude estimation performance are made between the EKF and the complementary filter.

  2. Miniature EVA Software Defined Radio

    Science.gov (United States)

    Pozhidaev, Aleksey

    2012-01-01

    As NASA embarks upon developing the Next-Generation Extra Vehicular Activity (EVA) Radio for deep space exploration, the demands on EVA battery life will substantially increase. The number of modes and frequency bands required will continue to grow in order to enable efficient and complex multi-mode operations including communications, navigation, and tracking applications. Whether conducting astronaut excursions, communicating to soldiers, or first responders responding to emergency hazards, NASA has developed an innovative, affordable, miniaturized, power-efficient software defined radio that offers unprecedented power-efficient flexibility. This lightweight, programmable, S-band, multi-service, frequency- agile EVA software defined radio (SDR) supports data, telemetry, voice, and both standard and high-definition video. Features include a modular design, an easily scalable architecture, and the EVA SDR allows for both stationary and mobile battery powered handheld operations. Currently, the radio is equipped with an S-band RF section. However, its scalable architecture can accommodate multiple RF sections simultaneously to cover multiple frequency bands. The EVA SDR also supports multiple network protocols. It currently implements a Hybrid Mesh Network based on the 802.11s open standard protocol. The radio targets RF channel data rates up to 20 Mbps and can be equipped with a real-time operating system (RTOS) that can be switched off for power-aware applications. The EVA SDR's modular design permits implementation of the same hardware at all Network Nodes concept. This approach assures the portability of the same software into any radio in the system. It also brings several benefits to the entire system including reducing system maintenance, system complexity, and development cost.

  3. Underground mine navigation using an integrated IMU/TOF system with unscented Kalman filter

    CSIR Research Space (South Africa)

    Hlophe, K

    2011-07-01

    Full Text Available & Factories of the Future Conference, 26-28 July 2011, Kuala Lumpur, Malaysia improve mine safety?, in 25th International Conference of CAD/CAM, Robotics & Factories of the Future, Pretoria, 2010. [2] J. J. Green and D. Vogt, Robot miner for low... Page 1 of 11 26th International Conference of CAD/CAM, Robotics & Factories of the Future Conference, 26-28 July 2011, Kuala Lumpur, Malaysia UNDERGROUND MINE NAVIGATION USING AN INTERGRATED IMU/TOF SYSTEM WITH UNSCENTED KALMAN FILTER...

  4. 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

  5. Flight results of attitude matching between Space Shuttle and Inertial Upper Stage (IUS) navigation systems

    Science.gov (United States)

    Treder, Alfred J.; Meldahl, Keith L.

    The recorded histories of Shuttle/Orbiter attitude and Inertial Upper Stage (IUS) attitude have been analyzed for all joint flights of the IUS in the Orbiter. This database was studied to determine the behavior of relative alignment between the IUS and Shuttle navigation systems. It is found that the overall accuracy of physical alignment has a Shuttle Orbiter bias component less than 5 arcmin/axis and a short-term stability upper bound of 0.5 arcmin/axis, both at 1 sigma. Summaries of the experienced physical and inertial alginment offsets are shown in this paper, together with alignment variation data, illustrated with some flight histories. Also included is a table of candidate values for some error source groups in an Orbiter/IUS attitude errror model. Experience indicates that the Shuttle is much more accurate and stable as an orbiting launch platform than has so far been advertised. This information will be valuable for future Shuttle payloads, especially those (such as the Aeroassisted Flight Experiment) which carry their own inertial navigation systems, and which could update or initialize their attitude determination systems using the Shuttle as the reference.

  6. An obstacle detection system using binocular stereo fisheye lenses for planetary rover navigation

    Science.gov (United States)

    Liu, L.; Jia, J.; Li, L.

    In this paper we present an implementation of an obstacle detection system using binocular stereo fisheye lenses for planetary rover navigation The fisheye lenses can improve image acquisition efficiency and handle minimal clearance recovery problem because they provide a large field of view However the fisheye lens introduces significant distortion in the image and this will make it much more difficult to find a one-to-one correspondence In addition we have to improve the system accuracy and efficiency for robot navigation To compute dense depth maps accurately in real time the following five key issues are considered 1 using lookup tables for a tradeoff between time and space in fisheye distortion correction and correspondence matching 2 using an improved incremental calculation scheme for algorithmic optimization 3 multimedia instruction set MMX implementation 4 consistency check to remove wrong stereo matching problems suffering from occlusions or mismatches 5 constraints of the recovery space To realize obstacle detection robustly we use the following three steps 1 extracting the ground plane parameters using Randomized Hough Transform 2 filtering the ground and background 3 locating the obstacles by using connected region detection Experimental results show the system can run at 3 2fps in 2 0GHz PC with 640X480 pixels

  7. Very-Long-Baseline Radio Interferometry: The Mark III System for Geodesy, Astrometry, and Aperture Synthesis.

    Science.gov (United States)

    Rogers, A E; Cappallo, R J; Hinteregger, H F; Levine, J I; Nesman, E F; Webber, J C; Whitney, A R; Clark, T A; Ma, C; Ryan, J; Corey, B E; Counselman, C C; Herring, T A; Shapiro, I I; Knight, C A; Shaffer, D B; Vandenberg, N R; Lacasse, R; Mauzy, R; Rayhrer, B; Schupler, B R; Pigg, J C

    1983-01-07

    The Mark III very-long-baseline interferometry (VLBI) system allows recording and later processing of up to 112 megabits per second from each radio telescope of an interferometer array. For astrometric and geodetic measurements, signals from two radio-frequency bands (2.2 to 2.3 and 8.2 to 8.6 gigahertz) are sampled and recorded simultaneously at all antenna sites. From these dual-band recordings the relative group delays of signals arriving at each pair of sites can be corrected for the contributions due to the ionosphere. For many radio sources for which the signals are sufficiently intense, these group delays can be determined with uncertainties under 50 picoseconds. Relative positions of widely separated antennas and celestial coordinates of radio sources have been determined from such measurements with 1 standard deviation uncertainties of about 5 centimeters and 3 milliseconds of arc, respectively. Sample results are given for the lengths of baselines between three antennas in the United States and three in Europe as well as for the arc lengths between the positions of six extragalactic radio sources. There is no significant evidence of change in any of these quantities. For mapping the brightness distribution of such compact radio sources, signals of a given polarization, or of pairs of orthogonal polarizations, can be recorded in up to 28 contiguous bands each nearly 2 megahertz wide. The ability to record large bandwidths and to link together many large radio telescopes allows detection and study of compact sources with flux densities under 1 millijansky.

  8. Reconstruction and navigation system for intraoperative brachytherapy using the flab technique for colorectal tumor bed irradiation

    International Nuclear Information System (INIS)

    Strassmann, Gerd; Walter, Stefan; Kolotas, Christos; Heyd, Reinhard; Baltas, Dimos; Debertshaeuser, Detlef; Nier, Helmut; Tonus, Carolin; Sakas, George; Zamboglou, Nikolaos

    2000-01-01

    Purpose: To present the development of a new navigation and reconstruction system based on an electromagnetic free-hand tracker and on CT imaging for treatment planning of intraoperative high-dose-rate brachytherapy (IORT-HDRB) in the sacral region. Our aim is to improve accuracy and to enable individualized treatment planning and dose documentation to be performed for IORT-HDRB using a flab technique. Methods and Materials: The material consists of an electromagnetic 3D tracker system, a PC workstation with Microsoft Windows NT 4.0 operating system, and a recognition program for continuous speech. In addition, we designed an external reference system constructed of titanium and Perspex, which is positioned in the pelvis, and a special digitizer pen for reconstruction of the flab geometry. The flab design incorporates a series of silicon 10-mm-diameter spherical pellets. Measurements were made with a pelvic phantom in order to study the accuracy of the system. The reconstruction results are stored and can be exported via network or floppy to our different treatment planning systems. Results: Our results for the reconstruction of a flab with six catheters and a total of 100 spherical pellets give mean errors in the range (2.5 ± 0.6) mm to (3.5 ± 0.8) mm depending on the positions of the pelvic phantom and transmitter relative to the operation table. These errors are calculated by comparing the reconstruction results of our system with those using a CT-based reconstruction of the flab geometry. For the accuracy of the navigation system for the pelvic phantom, we obtained mean errors in the range (2.2 ± 0.7) mm to (3.1 ± 1.0) mm. Conclusions: The new system we have developed enables navigation and reconstruction within the surgical environment with a clinically acceptable level of accuracy. It offers the possibility of individualized treatment planning and effective documentation of the 3D dose distribution in IORT-HDRB using a flab technique

  9. 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.

  10. 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.

  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. Gravity Compensation Using EGM2008 for High-Precision Long-Term Inertial Navigation Systems

    Directory of Open Access Journals (Sweden)

    Ruonan Wu

    2016-12-01

    Full Text Available The gravity disturbance vector is one of the major error sources in high-precision and long-term inertial navigation applications. Specific to the inertial navigation systems (INSs with high-order horizontal damping networks, analyses of the error propagation show that the gravity-induced errors exist almost exclusively in the horizontal channels and are mostly caused by deflections of the vertical (DOV. Low-frequency components of the DOV propagate into the latitude and longitude errors at a ratio of 1:1 and time-varying fluctuations in the DOV excite Schuler oscillation. This paper presents two gravity compensation methods using the Earth Gravitational Model 2008 (EGM2008, namely, interpolation from the off-line database and computing gravity vectors directly using the spherical harmonic model. Particular attention is given to the error contribution of the gravity update interval and computing time delay. It is recommended for the marine navigation that a gravity vector should be calculated within 1 s and updated every 100 s at most. To meet this demand, the time duration of calculating the current gravity vector using EGM2008 has been reduced to less than 1 s by optimizing the calculation procedure. A few off-line experiments were conducted using the data of a shipborne INS collected during an actual sea test. With the aid of EGM2008, most of the low-frequency components of the position errors caused by the gravity disturbance vector have been removed and the Schuler oscillation has been attenuated effectively. In the rugged terrain, the horizontal position error could be reduced at best 48.85% of its regional maximum. The experimental results match with the theoretical analysis and indicate that EGM2008 is suitable for gravity compensation of the high-precision and long-term INSs.

  13. Gravity Compensation Using EGM2008 for High-Precision Long-Term Inertial Navigation Systems.

    Science.gov (United States)

    Wu, Ruonan; Wu, Qiuping; Han, Fengtian; Liu, Tianyi; Hu, Peida; Li, Haixia

    2016-12-18

    The gravity disturbance vector is one of the major error sources in high-precision and long-term inertial navigation applications. Specific to the inertial navigation systems (INSs) with high-order horizontal damping networks, analyses of the error propagation show that the gravity-induced errors exist almost exclusively in the horizontal channels and are mostly caused by deflections of the vertical (DOV). Low-frequency components of the DOV propagate into the latitude and longitude errors at a ratio of 1:1 and time-varying fluctuations in the DOV excite Schuler oscillation. This paper presents two gravity compensation methods using the Earth Gravitational Model 2008 (EGM2008), namely, interpolation from the off-line database and computing gravity vectors directly using the spherical harmonic model. Particular attention is given to the error contribution of the gravity update interval and computing time delay. It is recommended for the marine navigation that a gravity vector should be calculated within 1 s and updated every 100 s at most. To meet this demand, the time duration of calculating the current gravity vector using EGM2008 has been reduced to less than 1 s by optimizing the calculation procedure. A few off-line experiments were conducted using the data of a shipborne INS collected during an actual sea test. With the aid of EGM2008, most of the low-frequency components of the position errors caused by the gravity disturbance vector have been removed and the Schuler oscillation has been attenuated effectively. In the rugged terrain, the horizontal position error could be reduced at best 48.85% of its regional maximum. The experimental results match with the theoretical analysis and indicate that EGM2008 is suitable for gravity compensation of the high-precision and long-term INSs.

  14. Millimeter-wave and Terahertz Reconfigurable Radio-over-Fiber Systems

    DEFF Research Database (Denmark)

    Vegas Olmos, Juan José

    when deploying fiber is not an option. Radio-over-Fiber (RoF) technologies have evolved from a blue sky academic topic in the 90s to a main driver within the current quest for the 5th generation mobile systems (5G). A twist in RoF technologies is that it has found along the way niches in areas non......, the complexity of fabrication and to integrate this solutions have to compete with the off-the-shelf solutions provided by RoF technologies. Technologically though, reconfigurable Radio-over-Fiber networks require a co-design effort involving tunable lasers, digital signal processing, high speed modulators...

  15. Radio frequency systems for present and future accelerators

    International Nuclear Information System (INIS)

    Raka, E.C.

    1987-01-01

    Rf systems are described for the FNAL Main Ring and Tevatron Ring, CERN SPS and LEP, and HERA proton acceleration system, CERN PS e + e/sup minus/ acceleration system, and CERN EPA monochromatic cavity. Low impedance rf systems in CERN ISR, the Brookhaven CBA, and SSC are also discussed

  16. On the throughput of cognitive radio MIMO systems assisted with UAV relays

    KAUST Repository

    Sboui, Lokman; Ghazzai, Hakim; Rezki, Zouheir; Alouini, Mohamed-Slim

    2017-01-01

    We analyze the achievable rates of a cognitive radio MIMO system assisted by an unmanned aerial vehicle (UAV) relay. The primary user (PU) and the secondary user (SU) aim to communicate to the closest primary base station (BS) via a multi

  17. Bandwidth and power allocation for two-way relaying in overlay cognitive radio systems

    KAUST Repository

    Alsharoa, Ahmad M.; Ghazzai, Hakim; Yaacoub, Elias E.; Alouini, Mohamed-Slim

    2014-01-01

    In this paper, the problem of both bandwidth and power allocation for two-way multiple relay systems in overlay cognitive radio (CR) setup is investigated. In the CR overlay mode, primary users (PUs) cooperate with cognitive users (CUs) for mutual

  18. 77 FR 28797 - Redundancy of Communications Systems: Backup Power Private Land Mobile Radio Services: Selection...

    Science.gov (United States)

    2012-05-16

    ... FEDERAL COMMUNICATIONS COMMISSION 47 CFR Parts 12 and 90 [DA 11-1838] Redundancy of Communications Systems: Backup Power Private Land Mobile Radio Services: Selection and Assignment of Frequencies, and Transition of the Upper 200 Channels in the 800 MHz Band to EA Licensing AGENCY: Federal Communications...

  19. Radio immune analysis of endocrine system state at exposure to different physical factors

    International Nuclear Information System (INIS)

    Rozdyil's'ka, O.M.; Rozdtil's'kij, S.Yi.; Bratchuk, O.M.; Yakimova, T.P.

    1999-01-01

    Radio immune analysis allows to define more exactly the mechanisms of physical factors action and may be used for validation of new therapeutic techniques. The ultra-high frequency magneto therapy, sinusoid modulated current and direct current influence the state of the endocrine system differently but within the physiological norm. The most prominent action of the physical factor is observed at trans cerebral mode

  20. On-board landmark navigation and attitude reference parallel processor system

    Science.gov (United States)

    Gilbert, L. E.; Mahajan, D. T.

    1978-01-01

    An approach to autonomous navigation and attitude reference for earth observing spacecraft is described along with the landmark identification technique based on a sequential similarity detection algorithm (SSDA). Laboratory experiments undertaken to determine if better than one pixel accuracy in registration can be achieved consistent with onboard processor timing and capacity constraints are included. The SSDA is implemented using a multi-microprocessor system including synchronization logic and chip library. The data is processed in parallel stages, effectively reducing the time to match the small known image within a larger image as seen by the onboard image system. Shared memory is incorporated in the system to help communicate intermediate results among microprocessors. The functions include finding mean values and summation of absolute differences over the image search area. The hardware is a low power, compact unit suitable to onboard application with the flexibility to provide for different parameters depending upon the environment.

  1. A multi-modality tracking, navigation and calibration for a flexible robotic drill system for total hip arthroplasty.

    Science.gov (United States)

    Ahmad Fuad, Ahmad Nazmi Bin; Deep, Kamal; Yao, Wei

    2018-02-01

    This paper presents a novel multi-modality tracking and navigation system that provides a unique capability to guild a flexible drill tip inside the bone with accurate curved tunnelling. As the flexible drill tip cannot be tracked optically inside the bone, this research focuses on developing a hybrid tracking and navigation system for tracking a flexible drill tip by using both optical and kinematic tracking. The tracking information is used to guide the THA (total hip arthroplasty) procedure, providing a real-time virtual model of the flexible drill. The flexible and steerable drill tip system is then tested on total hip arthroplasty followed by evaluation of the positioning and orientation of femoral stem placement by femoral milling. Based on this study, we conclude that the tracking and navigation system is able to guide the flexible drill to mill inside femoral canal. Copyright © 2017 John Wiley & Sons, Ltd.

  2. Radio Tracking Fish with Small Unmanned Aircraft Systems (sUAS).

    Science.gov (United States)

    Dahlgren, R. P.; Anderson, K. R.; Hanson, L.; Pinsker, E. A.; Jonsson, J.; Chapman, D. C.; Witten, D. M.; O'Connor, K. A.

    2017-12-01

    Tracking radio tagged fish by boat or on foot in riverine systems is difficult and time consuming, particularly in large braided island complexes, shallow wetlands, and rocky reaches. Invasive Asian carp are commonly found in these hard to reach areas, but their near-surface feeding behavior makes radio tracking possible. To identify new methods of fish tracking that could same time and money, this study tested the feasibility of tracking Asian carp with Small Unmanned Aerial Systems (sUAS) in areas generally inaccessible to traditional tracking equipment. The U.S. Geological Survey worked with NanoElectromagnetics LLC and WWR Development to create and integrate a lightweight custom radio receiver, directional antenna, and accompanying software into a sUAS platform. The receiver includes independent GPS, software defined radio, and compass. The NASA Ames Research Center (ARC) completed payload integration, electromagnetic-interference and airworthiness testing, and provided a DJI Matrice 600 sUAS for this study. Additionally, ARC provided subject matter experts, airworthiness and flight readiness evaluation, and flight test facilities during preparation; and a pilot, range safety officer, and aircraft engineer during field deployment. Results demonstrate that this custom sUAS and sensor combination can detect radio tags at 100m above ground level and at horizontal ranges of 100m and 300m, with operators in either onshore or offshore locations. With this combination of sUAS and radio receiver, fish can be tracked in areas previously inaccessible and during flooding, providing new insights into riverine fish movement and habitat utilization.

  3. An Interfacing System for Radiation Surveillance Using a Radio Communication Network

    International Nuclear Information System (INIS)

    Arunsiri, T.; Punnachaiya, S.; Pattarasumun, A.

    1998-01-01

    The development of an interfacing system for environmental radiation surveillance using radio communication network is aimed to improve a way by which environmental radiation measurement is transmitted and reported from the regional area monitoring station network. This also includes an automatic warning of beacon status via the radio link network to the center of environmental radiation control when an abnormal radiation level is detected. The interfacing system was developed by simulating the EGAT radio link network, the NT 2612, and can be separated into two parts. The first part was for a mobile station which can manage the output data from the radiation measurement system in the standard form of RS-232, IEEE-488, BCD and analog signal. This was accomplished by modulating the signal in selected baud rates ranging from 150 to 9600 bps using an economical radio packet capable of identifying and recalling the station code number. The other part is the linking system between the output data and the microcomputer equipped with a software to manage and evaluate the data from 10 surveillance stations for convenient handing of data output, statistical analysis and transmitting warning signal. Data transmission was tested using a baud rate of 1200 bps and was found to contain no detectable error when digital signal was transmitted while analog signal transmission resulted in deviations of less than ± 0.003%. The development of this radio link system provides a future trend for the environmental radiation monitoring network for countries with nuclear power plants or neighboring countries needed to continuously monitor for any abnormal radiation level in the environment. In case that the radiation surveillance system detects a high level of radiation, a warning signal will be transmitted and appropriate actions may be immediately exercised to control impacts of radiation on environment and living things according to international guidelines

  4. Space-Based Reconfigurable Software Defined Radio Test Bed Aboard International Space Station

    Science.gov (United States)

    Reinhart, Richard C.; Lux, James P.

    2014-01-01

    The National Aeronautical and Space Administration (NASA) recently launched a new software defined radio research test bed to the International Space Station. The test bed, sponsored by the Space Communications and Navigation (SCaN) Office within NASA is referred to as the SCaN Testbed. The SCaN Testbed is a highly capable communications system, composed of three software defined radios, integrated into a flight system, and mounted to the truss of the International Space Station. Software defined radios offer the future promise of in-flight reconfigurability, autonomy, and eventually cognitive operation. The adoption of software defined radios offers space missions a new way to develop and operate space transceivers for communications and navigation. Reconfigurable or software defined radios with communications and navigation functions implemented in software or VHDL (Very High Speed Hardware Description Language) provide the capability to change the functionality of the radio during development or after launch. The ability to change the operating characteristics of a radio through software once deployed to space offers the flexibility to adapt to new science opportunities, recover from anomalies within the science payload or communication system, and potentially reduce development cost and risk by adapting generic space platforms to meet specific mission requirements. The software defined radios on the SCaN Testbed are each compliant to NASA's Space Telecommunications Radio System (STRS) Architecture. The STRS Architecture is an open, non-proprietary architecture that defines interfaces for the connections between radio components. It provides an operating environment to abstract the communication waveform application from the underlying platform specific hardware such as digital-to-analog converters, analog-to-digital converters, oscillators, RF attenuators, automatic gain control circuits, FPGAs, general-purpose processors, etc. and the interconnections among

  5. Migration in the Anthropocene: how collective navigation, environmental system and taxonomy shape the vulnerability of migratory species.

    Science.gov (United States)

    Hardesty-Moore, Molly; Deinet, Stefanie; Freeman, Robin; Titcomb, Georgia C; Dillon, Erin M; Stears, Keenan; Klope, Maggie; Bui, An; Orr, Devyn; Young, Hillary S; Miller-Ter Kuile, Ana; Hughey, Lacey F; McCauley, Douglas J

    2018-05-19

    Recent increases in human disturbance pose significant threats to migratory species using collective movement strategies. Key threats to migrants may differ depending on behavioural traits (e.g. collective navigation), taxonomy and the environmental system (i.e. freshwater, marine or terrestrial) associated with migration. We quantitatively assess how collective navigation, taxonomic membership and environmental system impact species' vulnerability by (i) evaluating population change in migratory and non-migratory bird, mammal and fish species using the Living Planet Database (LPD), (ii) analysing the role of collective navigation and environmental system on migrant extinction risk using International Union for Conservation of Nature (IUCN) classifications and (iii) compiling literature on geographical range change of migratory species. Likelihood of population decrease differed by taxonomic group: migratory birds were more likely to experience annual declines than non-migrants, while mammals displayed the opposite pattern. Within migratory species in IUCN, we observed that collective navigation and environmental system were important predictors of extinction risk for fishes and birds, but not for mammals, which had overall higher extinction risk than other taxa. We found high phylogenetic relatedness among collectively navigating species, which could have obscured its importance in determining extinction risk. Overall, outputs from these analyses can help guide strategic interventions to conserve the most vulnerable migrations.This article is part of the theme issue 'Collective movement ecology'. © 2018 The Author(s).

  6. Management system quality of service radio physics and RR. ISO 9001

    International Nuclear Information System (INIS)

    Gil Agudo, A.; Torres Donaire, J.; Jimenez, J. C.; Carrascosa Fernandez, C.; Arjona Gutierrez, J.

    2011-01-01

    One of the tool increasingly deployed for the optimization of the procedures is the process management system according to a Quality Management. Likewise, for specific areas, such as central services within large institutions such as the General Hospitals of the systems of quality management is the most widely used ISO 9001. We describe in this paper our experience in implementing the system ISO 9001 in our Department of Radio physics and Radiation Protection (SRFPR).

  7. A low-power photovoltaic system with energy storage for radio communications: Description and design methodology

    Science.gov (United States)

    Chapman, C. P.; Chapman, P. D.; Lewison, A. H.

    1982-01-01

    A low power photovoltaic system was constructed with approximately 500 amp hours of battery energy storage to provide power to an emergency amateur radio communications center. The system can power the communications center for about 72 hours of continuous nonsun operation. Complete construction details and a design methodology algorithm are given with abundant engineering data and adequate theory to allow similar systems to be constructed, scaled up or down, with minimum design effort.

  8. Interlocks for the LEP Radio-Frequency System

    CERN Document Server

    Livesley, S

    2000-01-01

    Interlocks for the LEP RF system totalled more than 7000. They provided protection for the personnel and a wide range of equipment: copper cavities, superconducting cavities, klystrons and high voltage equipment. The interlock system layout, functionality and components are described.

  9. Radio resource management for next generation mobile communication systems

    DEFF Research Database (Denmark)

    Wang, Hua

    The key feature of next generation (4G) mobile communication system is the ability to deliver a variety of multimedia services with different Quality-of-Service (QoS) requirements. Compared to the third generation (3G) mobile communication systems, 4G mobile communication system introduces several...

  10. Reconfigurable/Reprogrammable Communications Systems, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA's latest effort in developing a common platform for space communication and navigation systems is the Space Telecommunications Radio System (STRS) standard. It...

  11. Drift Reduction in Pedestrian Navigation System by Exploiting Motion Constraints and Magnetic Field

    Directory of Open Access Journals (Sweden)

    Muhammad Ilyas

    2016-09-01

    Full Text Available Pedestrian navigation systems (PNS using foot-mounted MEMS inertial sensors use zero-velocity updates (ZUPTs to reduce drift in navigation solutions and estimate inertial sensor errors. However, it is well known that ZUPTs cannot reduce all errors, especially as heading error is not observable. Hence, the position estimates tend to drift and even cyclic ZUPTs are applied in updated steps of the Extended Kalman Filter (EKF. This urges the use of other motion constraints for pedestrian gait and any other valuable heading reduction information that is available. In this paper, we exploit two more motion constraints scenarios of pedestrian gait: (1 walking along straight paths; (2 standing still for a long time. It is observed that these motion constraints (called “virtual sensor”, though considerably reducing drift in PNS, still need an absolute heading reference. One common absolute heading estimation sensor is the magnetometer, which senses the Earth’s magnetic field and, hence, the true heading angle can be calculated. However, magnetometers are susceptible to magnetic distortions, especially in indoor environments. In this work, an algorithm, called magnetic anomaly detection (MAD and compensation is designed by incorporating only healthy magnetometer data in the EKF updating step, to reduce drift in zero-velocity updated INS. Experiments are conducted in GPS-denied and magnetically distorted environments to validate the proposed algorithms.

  12. Application of the spherical harmonic gravity model in high precision inertial navigation systems

    International Nuclear Information System (INIS)

    Wang, Jing; Yang, Gongliu; Zhou, Xiao; Li, Xiangyun

    2016-01-01

    The spherical harmonic gravity model (SHM) may, in general, be considered as a suitable alternative to the normal gravity model (NGM), because it represents the Earth’s gravitational field more accurately. However, the high-resolution SHM has never been used in current inertial navigation systems (INSs) due to its extremely complex expression. In this paper, the feasibility and accuracy of a truncated SHM are discussed for application in a real-time free-INS with a precision demand better than 0.8 nm h −1 . In particular, the time and space complexity are analyzed mathematically to verify the feasibility of the SHM. Also, a test on a typical navigation computer shows a storable range of cut-off degrees. To further evaluate the appropriate degree and accuracy of the truncated SHM, analyses of covariance and truncation error are proposed. Finally, a SHM of degree 12 is demonstrated to be the appropriate model for routine INSs in the precision range of 0.4–0.75 nm h −1 . Flight simulations and road tests show its outstanding performance over the traditional NGM. (paper)

  13. Estimating Zenith Tropospheric Delays from BeiDou Navigation Satellite System Observations

    Directory of Open Access Journals (Sweden)

    Xin Sui

    2013-04-01

    Full Text Available The GNSS derived Zenith Tropospheric Delay (ZTD plays today a very critical role in meteorological study and weather forecasts, as ZTDs of thousands of GNSS stations are operationally assimilated into numerical weather prediction models. Recently, the Chinese BeiDou Navigation Satellite System (BDS was officially announced to provide operational services around China and its neighborhood and it was demonstrated to be very promising for precise navigation and positioning. In this contribution, we concentrate on estimating ZTD using BDS observations to assess its capacity for troposphere remote sensing. A local network which is about 250 km from Beijing and comprised of six stations equipped with GPS- and BDS-capable receivers is utilized. Data from 5 to 8 November 2012 collected on the network is processed in network mode using precise orbits and in Precise Point Positioning mode using precise orbits and clocks. The precise orbits and clocks are generated from a tracking network with most of the stations in China and several stations around the world. The derived ZTDs are compared with that estimated from GPS data using the final products of the International GNSS Service (IGS. The comparison shows that the bias and the standard deviation of the ZTD differences are about 2 mm and 5 mm, respectively, which are very close to the differences of GPS ZTD estimated using different software packages.

  14. 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

  15. Comparison of two navigation systems for CT-guided interventions under special consideration of the ergonomic properties of the used systems

    International Nuclear Information System (INIS)

    Schulz, T.; Roettger, S.; Bahner-Heyne, E.J.; Kluge, G.

    2009-01-01

    Purpose: investigation of the influence of CT-based navigation systems on the success of an intervention, assessment of the advantages and disadvantages of the utilized systems, and evaluation of the ergonomic system properties. Materials and method: a simple guiding system PatPos Invent trademark and the computer-based navigation system PinPoint trademark were employed on two CT systems. In order to investigate the influence of the navigation aids on the success of the interventions, 96 prospective, randomized, and standardized punctures were performed on a specifically developed, rigid phantom. 16 examiners punctured 6 targets with 3 degrees of difficulty with the navigation aids. Results: irrespective of the experience of the examiner, both navigation systems guided the target with an equal degree of certainty. PinPoint significantly reduced the length of the examination time (12 - 25 min) as compared to PatPos Invent (20 - 40 min). The expectation conformity and comprehensibility of PatPos Invent were assessed significantly more positively than PinPoint with regard to the general handling of the system. In contrast, the assessment of the usability during preoperative setup favored PinPoint. The type of navigation system has no influence on the precision of the implementation of a puncture procedure. (orig.)

  16. Vibrotactile Feedbacks System for Assisting the Physically Impaired Persons for Easy Navigation

    Science.gov (United States)

    Safa, M.; Geetha, G.; Elakkiya, U.; Saranya, D.

    2018-04-01

    NAYAN architecture is for a visually impaired person to help for navigation. As well known, all visually impaired people desperately requires special requirements even to access services like the public transportation. This prototype system is a portable device; it is so easy to carry in any conduction to travel through a familiar and unfamiliar environment. The system consists of GPS receiver and it can get NEMA data through the satellite and it is provided to user's Smartphone through Arduino board. This application uses two vibrotactile feedbacks that will be placed in the left and right shoulder for vibration feedback, which gives information about the current location. The ultrasonic sensor is used for obstacle detection which is found in front of the visually impaired person. The Bluetooth modules connected with Arduino board is to send information to the user's mobile phone which it receives from GPS.

  17. Refurbishment and upgrading of Iron Gates I Hydroelectric and Navigation System on the Danube River

    International Nuclear Information System (INIS)

    Scvortov, F.; Vasiliu, A.; Rosca, N.

    1996-01-01

    This work shows the problems of the refurbishing the hydroelectric units of the Iron Gates 1 Hydroelectric and Navigation System, operating since 1970. Their long and intensive utilization leads to the necessity of their refurbishment. One is demonstrated by detailed studies that it is sensible and efficient to perform both rehabilitation of the existent hydroelectric units and their power increasing from 175 MW to 190 MW, and prior to all these, as a first step, to install an additional hydroelectric unit (G7) for each system with a capacity of 190 MW. Complex technical and energetic-economical problems appear in realizing this objective due to the necessity of analysing a great volume of data in view of taking a correct decision. (author). 7 figs

  18. FRESH ACTIVITY IN OLD SYSTEMS: RADIO AGNs IN FOSSIL GROUPS OF GALAXIES

    International Nuclear Information System (INIS)

    Hess, Kelley M.; Wilcots, Eric M.; Hartwick, Victoria L.

    2012-01-01

    We present the first systematic 1.4 GHz Very Large Array radio continuum survey of fossil galaxy group candidates. These are virialized systems believed to have assembled over a gigayear in the past through the merging of galaxy group members into a single, isolated, massive elliptical galaxy and featuring an extended hot X-ray halo. We use new photometric and spectroscopic data from Sloan Digital Sky Survey Data Release 7 to determine that three of the candidates are clearly not fossil groups. Of the remaining 30 candidates, 67% contain a radio-loud (L 1.4GHz > 10 23 W Hz –1 ) active galactic nucleus (AGN) at the center of their dominant elliptical galaxy. We find a weak correlation between the radio luminosity of the AGN and the X-ray luminosity of the halo suggesting that the AGN contributes to energy deposition into the intragroup medium. We only find a correlation between the radio and optical luminosity of the central elliptical galaxy when we include X-ray-selected, elliptically dominated non-fossil groups, indicating a weak relationship between AGN strength and the mass assembly history of the groups. The dominant elliptical galaxy of fossil groups is on average roughly an order of magnitude more luminous than normal group elliptical galaxies in optical, X-ray, and radio luminosities and our findings are consistent with previous results that the radio-loud fraction in elliptical galaxies is linked to the stellar mass of a population. The current level of activity in fossil groups suggests that AGN fueling continues long after the last major merger. We discuss several possibilities for fueling the AGN at the present epoch.

  19. DEVELOPMENT OF A PEDESTRIAN INDOOR NAVIGATION SYSTEM BASED ON MULTI-SENSOR FUSION AND FUZZY LOGIC ESTIMATION ALGORITHMS

    Directory of Open Access Journals (Sweden)

    Y. C. Lai

    2015-05-01

    Full Text Available This paper presents a pedestrian indoor navigation system based on the multi-sensor fusion and fuzzy logic estimation algorithms. The proposed navigation system is a self-contained dead reckoning navigation that means no other outside signal is demanded. In order to achieve the self-contained capability, a portable and wearable inertial measure unit (IMU has been developed. Its adopted sensors are the low-cost inertial sensors, accelerometer and gyroscope, based on the micro electro-mechanical system (MEMS. There are two types of the IMU modules, handheld and waist-mounted. The low-cost MEMS sensors suffer from various errors due to the results of manufacturing imperfections and other effects. Therefore, a sensor calibration procedure based on the scalar calibration and the least squares methods has been induced in this study to improve the accuracy of the inertial sensors. With the calibrated data acquired from the inertial sensors, the step length and strength of the pedestrian are estimated by multi-sensor fusion and fuzzy logic estimation algorithms. The developed multi-sensor fusion algorithm provides the amount of the walking steps and the strength of each steps in real-time. Consequently, the estimated walking amount and strength per step are taken into the proposed fuzzy logic estimation algorithm to estimates the step lengths of the user. Since the walking length and direction are both the required information of the dead reckoning navigation, the walking direction is calculated by integrating the angular rate acquired by the gyroscope of the developed IMU module. Both the walking length and direction are calculated on the IMU module and transmit to a smartphone with Bluetooth to perform the dead reckoning navigation which is run on a self-developed APP. Due to the error accumulating of dead reckoning navigation, a particle filter and a pre-loaded map of indoor environment have been applied to the APP of the proposed navigation system

  20. Development of a Pedestrian Indoor Navigation System Based on Multi-Sensor Fusion and Fuzzy Logic Estimation Algorithms

    Science.gov (United States)

    Lai, Y. C.; Chang, C. C.; Tsai, C. M.; Lin, S. Y.; Huang, S. C.

    2015-05-01

    This paper presents a pedestrian indoor navigation system based on the multi-sensor fusion and fuzzy logic estimation algorithms. The proposed navigation system is a self-contained dead reckoning navigation that means no other outside signal is demanded. In order to achieve the self-contained capability, a portable and wearable inertial measure unit (IMU) has been developed. Its adopted sensors are the low-cost inertial sensors, accelerometer and gyroscope, based on the micro electro-mechanical system (MEMS). There are two types of the IMU modules, handheld and waist-mounted. The low-cost MEMS sensors suffer from various errors due to the results of manufacturing imperfections and other effects. Therefore, a sensor calibration procedure based on the scalar calibration and the least squares methods has been induced in this study to improve the accuracy of the inertial sensors. With the calibrated data acquired from the inertial sensors, the step length and strength of the pedestrian are estimated by multi-sensor fusion and fuzzy logic estimation algorithms. The developed multi-sensor fusion algorithm provides the amount of the walking steps and the strength of each steps in real-time. Consequently, the estimated walking amount and strength per step are taken into the proposed fuzzy logic estimation algorithm to estimates the step lengths of the user. Since the walking length and direction are both the required information of the dead reckoning navigation, the walking direction is calculated by integrating the angular rate acquired by the gyroscope of the developed IMU module. Both the walking length and direction are calculated on the IMU module and transmit to a smartphone with Bluetooth to perform the dead reckoning navigation which is run on a self-developed APP. Due to the error accumulating of dead reckoning navigation, a particle filter and a pre-loaded map of indoor environment have been applied to the APP of the proposed navigation system to extend its

  1. Analysis and Compensation of Modulation Angular Rate Error Based on Missile-Borne Rotation Semi-Strapdown Inertial Navigation System

    Directory of Open Access Journals (Sweden)

    Jiayu Zhang

    2018-05-01

    Full Text Available The Semi-Strapdown Inertial Navigation System (SSINS provides a new solution to attitude measurement of a high-speed rotating missile. However, micro-electro-mechanical-systems (MEMS inertial measurement unit (MIMU outputs are corrupted by significant sensor errors. In order to improve the navigation precision, a rotation modulation technology method called Rotation Semi-Strapdown Inertial Navigation System (RSSINS is introduced into SINS. In fact, the stability of the modulation angular rate is difficult to achieve in a high-speed rotation environment. The changing rotary angular rate has an impact on the inertial sensor error self-compensation. In this paper, the influence of modulation angular rate error, including acceleration-deceleration process, and instability of the angular rate on the navigation accuracy of RSSINS is deduced and the error characteristics of the reciprocating rotation scheme are analyzed. A new compensation method is proposed to remove or reduce sensor errors so as to make it possible to maintain high precision autonomous navigation performance by MIMU when there is no external aid. Experiments have been carried out to validate the performance of the method. In addition, the proposed method is applicable for modulation angular rate error compensation under various dynamic conditions.

  2. System of the optic-electronic sensors for control position of the radio telescope elements

    Science.gov (United States)

    Konyakhin, Igor; Stepashkin, Ivan; Petrochenko, Andrey

    2016-04-01

    A promising area of modern astronomy is the study of the field of millimeter waves. The use of this band is due to a large extent the spectrum characteristics of the propagation of waves in the atmosphere, short wavelength. Currently, Russia jointly with Uzbekistan is implementing a project to build a radio astronomy observatory on the Suffa plateau (Uzbekistan). The main instrument of the observatory is fully steerable radio telescope RT-70 type. Main mirror telescope is a fragment of an axisymmetric parabolic with a focal length of 21 m, consisting of 1200 reflecting panels; main mirror diameter - 70 m; diameter of counter reflector - 3 m. A feature of the radio telescope as a means of research in the millimeter wavelength range are high for the quality requirements parabolic surface of the primary mirror (standard deviation of points on the surface of the theoretical parabolic is not more than 0.05 mm), to the stability of the mutual arrangement of the primary mirror and the counter reflector (not more than 0, 07 mm) for precision guidance in the corners of the mirror system azimuth and elevation (margin of error 1.5-2"). Weight of structure, temperature changes and air shock result in significant deformation elements radio telescope construction (progressive linear displacements of points of the surface of the main mirror), reaching in the marginal zone of 30 mm; counter reflector shift of up to 60 mm; Unlike the angular position of the axis of the beam pattern of the radio telescope of the measured angle transducers can reach 10 ". Therefore, to ensure the required quality of the reflective elements RT-70 systems, as well as the implementation of precision-guided munitions needs complex measuring deformation elements telescope design. This article deals with the construction of opto-electronic system of remote optoelectronic displacement sensor control elements mirror telescope system.

  3. Multistandard Radio Systems: State of the Art and Research Issues

    DEFF Research Database (Denmark)

    Zakrzewska, Anna; Berger, Michael Stübert; Ruepp, Sarah Renée

    2010-01-01

    Integration of various wireless standards and building one consistent and compatible broadband system is a trend in wireless communication nowadays. This work focuses on multistandard networks enabling the cooperation between LTE and WiMAX systems. It presents the general vision on multistandard ...... systems and current possibilities of such integration. Furthermore, key features and challenges of developing this kind of network are discussed along with the proposed solutions and their performance benefits....

  4. Radio Interferometric Research of Ionosphere by Signals of Space Satellites

    Directory of Open Access Journals (Sweden)

    Dugin N.

    2013-03-01

    Full Text Available Since 2012, the Radiophysical Research Institute and the Lobachevsky State University at Nizhny Novgorod, Russia and the Ventspils International Radio Astronomy Centre at Irbene, Latvia are making radio interferometric experiments on study of ionosphere parameters in a quiet (natural state of medium and research of artificial turbulence of the ionosphere, heated by the emission from the SURA facility. Remote diagnostics of the ionosphere is implemented using a method of radio sounding by signals of navigation satellites in combination with the Very Long Baseline Interferometry (VLBI method. As a result of spectral and correlation analysis, interferometric responses of the two-element (RRI–UNN and three-element (RRI–UNN–Irbene interferometers were received by observations of 12 satellites of the navigation systems GLONASS and GPS. Here the first results are reported.

  5. A bronchoscopic navigation system using bronchoscope center calibration for accurate registration of electromagnetic tracker and CT volume without markers

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Xiongbiao, E-mail: xiongbiao.luo@gmail.com [Robarts Research Institute, Western University, London, Ontario N6A 5K8 (Canada)

    2014-06-15

    Purpose: Various bronchoscopic navigation systems are developed for diagnosis, staging, and treatment of lung and bronchus cancers. To construct electromagnetically navigated bronchoscopy systems, registration of preoperative images and an electromagnetic tracker must be performed. This paper proposes a new marker-free registration method, which uses the centerlines of the bronchial tree and the center of a bronchoscope tip where an electromagnetic sensor is attached, to align preoperative images and electromagnetic tracker systems. Methods: The chest computed tomography (CT) volume (preoperative images) was segmented to extract the bronchial centerlines. An electromagnetic sensor was fixed at the bronchoscope tip surface. A model was designed and printed using a 3D printer to calibrate the relationship between the fixed sensor and the bronchoscope tip center. For each sensor measurement that includes sensor position and orientation information, its corresponding bronchoscope tip center position was calculated. By minimizing the distance between each bronchoscope tip center position and the bronchial centerlines, the spatial alignment of the electromagnetic tracker system and the CT volume was determined. After obtaining the spatial alignment, an electromagnetic navigation bronchoscopy system was established to real-timely track or locate a bronchoscope inside the bronchial tree during bronchoscopic examinations. Results: The electromagnetic navigation bronchoscopy system was validated on a dynamic bronchial phantom that can simulate respiratory motion with a breath rate range of 0–10 min{sup −1}. The fiducial and target registration errors of this navigation system were evaluated. The average fiducial registration error was reduced from 8.7 to 6.6 mm. The average target registration error, which indicates all tracked or navigated bronchoscope position accuracy, was much reduced from 6.8 to 4.5 mm compared to previous registration methods. Conclusions: An

  6. A bronchoscopic navigation system using bronchoscope center calibration for accurate registration of electromagnetic tracker and CT volume without markers

    International Nuclear Information System (INIS)

    Luo, Xiongbiao

    2014-01-01

    Purpose: Various bronchoscopic navigation systems are developed for diagnosis, staging, and treatment of lung and bronchus cancers. To construct electromagnetically navigated bronchoscopy systems, registration of preoperative images and an electromagnetic tracker must be performed. This paper proposes a new marker-free registration method, which uses the centerlines of the bronchial tree and the center of a bronchoscope tip where an electromagnetic sensor is attached, to align preoperative images and electromagnetic tracker systems. Methods: The chest computed tomography (CT) volume (preoperative images) was segmented to extract the bronchial centerlines. An electromagnetic sensor was fixed at the bronchoscope tip surface. A model was designed and printed using a 3D printer to calibrate the relationship between the fixed sensor and the bronchoscope tip center. For each sensor measurement that includes sensor position and orientation information, its corresponding bronchoscope tip center position was calculated. By minimizing the distance between each bronchoscope tip center position and the bronchial centerlines, the spatial alignment of the electromagnetic tracker system and the CT volume was determined. After obtaining the spatial alignment, an electromagnetic navigation bronchoscopy system was established to real-timely track or locate a bronchoscope inside the bronchial tree during bronchoscopic examinations. Results: The electromagnetic navigation bronchoscopy system was validated on a dynamic bronchial phantom that can simulate respiratory motion with a breath rate range of 0–10 min −1 . The fiducial and target registration errors of this navigation system were evaluated. The average fiducial registration error was reduced from 8.7 to 6.6 mm. The average target registration error, which indicates all tracked or navigated bronchoscope position accuracy, was much reduced from 6.8 to 4.5 mm compared to previous registration methods. Conclusions: An

  7. Empowering file-based radio production through media asset management systems

    Science.gov (United States)

    Muylaert, Bjorn; Beckers, Tom

    2006-10-01

    In recent years, IT-based production and archiving of media has matured to a level which enables broadcasters to switch over from tape- or CD-based to file-based workflows for the production of their radio and television programs. This technology is essential for the future of broadcasters as it provides the flexibility and speed of execution the customer demands by enabling, among others, concurrent access and production, faster than real-time ingest, edit during ingest, centrally managed annotation and quality preservation of media. In terms of automation of program production, the radio department is the most advanced within the VRT, the Flemish broadcaster. Since a couple of years ago, the radio department has been working with digital equipment and producing its programs mainly on standard IT equipment. Historically, the shift from analogue to digital based production has been a step by step process initiated and coordinated by each radio station separately, resulting in a multitude of tools and metadata collections, some of them developed in-house, lacking integration. To make matters worse, each of those stations adopted a slightly different production methodology. The planned introduction of a company-wide Media Asset Management System allows a coordinated overhaul to a unified production architecture. Benefits include the centralized ingest and annotation of audio material and the uniform, integrated (in terms of IT infrastructure) workflow model. Needless to say, the ingest strategy, metadata management and integration with radio production systems play a major role in the level of success of any improvement effort. This paper presents a data model for audio-specific concepts relevant to radio production. It includes an investigation of ingest techniques and strategies. Cooperation with external, professional production tools is demonstrated through a use-case scenario: the integration of an existing, multi-track editing tool with a commercially available

  8. Novel Radio Architectures for UWB, 60 GHz, and Cognitive Wireless Systems

    Directory of Open Access Journals (Sweden)

    Cabric Danijela

    2006-01-01

    Full Text Available There are several new radio systems which exploit novel strategies being made possible by the regulatory agencies to increase the availability of spectrum for wireless applications. Three of these that will be discussed are ultra-wideband (UWB, 60 GHz, and cognitive radios. The UWB approach attempts to share the spectrum with higher-priority users by transmitting at power levels that are so low that they do not cause interference. On the other hand, cognitive radios attempt to share spectra by introducing a spectrum sensing function, so that they are able to transmit in unused portions at a given time, place, and frequency. Another approach is to exploit the advances in CMOS technology to operate in frequency bands in the millimeter-wave region. 60 GHz operation is particularly attractive because of the 7 GHz of unlicensed spectrum that has been made available there. In this paper, we present an overview of novel radio architecture design approaches and address challenges dealing with high-frequencies, wide-bandwidths, and large dynamic-range signals encountered in these future wireless systems.

  9. Removing radio-active wastes from nuclear power stations by the STEAG system

    International Nuclear Information System (INIS)

    Baatz, H.

    1978-01-01

    The mobile STEAG System for conditioning radio-active wastes from nuclear power stations represents a particularly safe and economic method of removing them in present day conditions. Cementation by the FAFNIR System is used for the greater part of the waste, the liquid concentrate (evaporator concentrate and filter slurry). For the special case of the medium active resin balls from the primary circuits, embedding in plastic by the FAMA process has proved to be the only available successful process so far. The highly active solid waste from the reactor core is decomposed by the MOSAIK System, is packed in transportable and storable containers and is removed from the fuel element storage pond. The systems are so safe that faults or interruptions of power station operation due to faults in removing radio-active wastes can be excluded. (orig.) [de

  10. 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

  11. High-Performance Control in Radio Frequency Power Amplification Systems

    DEFF Research Database (Denmark)

    Høyerby, Mikkel Christian Kofod

    . It is clearly shown that single-phase switch-mode control systems based on oscillation (controlled unstable operation) of the whole power train provide the highest possible control bandwidth. A study of the limitations of cartesian feedback is also included. It is shown that bandwidths in excess of 4MHz can...... frequency power amplifiers (RFPAs) in conjunction with cartesian feedback (CFB) used to linearize the overall transmitter system. On a system level, it is demonstrated how envelope tracking is particularly useful for RF carriers with high peak-to-average power ratios, such as TEDS with 10dB. It is also...... demonstrated how the envelope tracking technique introduces a number of potential pitfalls to the system, namely in the form of power supply ripple intermodulation (PSIM), reduced RFPA linearity and a higherimpedance supply rail for the RFPA. Design and analysis techniques for these three issues are introduced...

  12. Measurement Technique in Radio Frequency Interference (RFI) Study for Radio Astronomy Purposes

    International Nuclear Information System (INIS)

    Roslan Umar; Roslan Umar; Nor Hazmin Sabri; Zainol Abidin Ibrahim; Zamri Zainal Abidin; Asyaari Muhamad

    2015-01-01

    In this paper, we will review our method in making measurements of radio frequency interference (RFI) in order to investigate the sereneness of interference in selected radio interference in Malaysia and Thailand. The selected site are University of Malaya (UM), Universiti Pendidikan Sultan Idris (UPSI), Ubon (UB) and Chiang Mai (CM). The major RFI affecting radio astronomical windows below 1 GHz are electronic equipment system specifically radio navigation between 73.1 MHz and 75.2 MHz, radio broadcasting (151 MHz, 151.8 MHz and 152 MHz), aeronautical navigation (245.5 MHz, 248.7 MHz and 249 MHz and also fixed mobile at 605 MHz, 608.3 MHz, 612.2 MHz, 613.3 MHz. It is obviously showed that all sites within this region are free from interference between 320MHz and 330 MHz and is the best specific region to be considered for solar burst monitoring. We also investigate the effect of RFI on discovery of solar burst. (author)

  13. A new non-thermal galactic radio source with a possible binary system

    International Nuclear Information System (INIS)

    Fuerst, E.; Reich, W.; Reich, P.; Sofue, Y.; Handa, T.

    1985-01-01

    A galactic object [G18.95-1.1], detected recently in a galactic plane survey, may belong to a new class of non-thermal radio sources that originate in accreting binary systems. The data on integrated flux density spectral index and the polarization, proves the non-thermal nature of the source. The morphology defies any classification as a supernova remnant. The authors suggest that the object is a binary system containing a compact component. (U.K.)

  14. History and Technology Developments of Radio Frequency (RF) Systems for Particle Accelerators

    Science.gov (United States)

    Nassiri, A.; Chase, B.; Craievich, P.; Fabris, A.; Frischholz, H.; Jacob, J.; Jensen, E.; Jensen, M.; Kustom, R.; Pasquinelli, R.

    2016-04-01

    This article attempts to give a historical account and review of technological developments and innovations in radio frequency (RF) systems for particle accelerators. The evolution from electrostatic field to the use of RF voltage suggested by R. Wideröe made it possible to overcome the shortcomings of electrostatic accelerators, which limited the maximum achievable electric field due to voltage breakdown. After an introduction, we will provide reviews of technological developments of RF systems for particle accelerators.

  15. Radio Frequency Identification (RFID) Based Employee Attendance Management System

    Science.gov (United States)

    Maramis, G. D. P.; Rompas, P. T. D.

    2018-02-01

    Manually recorded attendance of all the employees has produced some problems such as the data accuracy and staff performance efficiency. The objective of this research is to design and develop a software of RFID attendance system which is integrated with database system. This RFID attendance system was developed using several main components such as tags that will be used as a replacement of ID cards and a reader device that will read the information related to the employee attendance. The result of this project is a software of RFID attendance system that is integrated with the database and has a function to store the data or information of every single employee. This system has a maximum reading range of 2 cm with success probability of 1 and requires a minimum interval between readings of 2 seconds in order to achieve an optimal functionality. By using the system, the discipline attitude of the employees and also the performance of the staff will be improved instantly.

  16. Application of a real-time three-dimensional navigation system to various oral and maxillofacial surgical procedures.

    Science.gov (United States)

    Ohba, Seigo; Yoshimura, Hitoshi; Ishimaru, Kyoko; Awara, Kousuke; Sano, Kazuo

    2015-09-01

    The aim of this study was to confirm the effectiveness of a real-time three-dimensional navigation system for use during various oral and maxillofacial surgeries. Five surgeries were performed with this real-time three-dimensional navigation system. For mandibular surgery, patients wore acrylic surgical splints when they underwent computed tomography examinations and the operation to maintain the mandibular position. The incidence of complications during and after surgery was assessed. No connection with the nasal cavity or maxillary sinus was observed at the maxilla during the operation. The inferior alveolar nerve was not injured directly, and any paresthesia around the lower lip and mental region had disappeared within several days after the surgery. In both maxillary and mandibular cases, there was no abnormal hemorrhage during or after the operation. Real-time three-dimensional computer-navigated surgery allows minimally invasive, safe procedures to be performed with precision. It results in minimal complications and early recovery.

  17. Development of an online radiology case review system featuring interactive navigation of volumetric image datasets using advanced visualization techniques

    International Nuclear Information System (INIS)

    Yang, Hyun Kyung; Kim, Boh Kyoung; Jung, Ju Hyun; Kang, Heung Sik; Lee, Kyoung Ho; Woo, Hyun Soo; Jo, Jae Min; Lee, Min Hee

    2015-01-01

    To develop an online radiology case review system that allows interactive navigation of volumetric image datasets using advanced visualization techniques. Our Institutional Review Board approved the use of the patient data and waived the need for informed consent. We determined the following system requirements: volumetric navigation, accessibility, scalability, undemanding case management, trainee encouragement, and simulation of a busy practice. The system comprised a case registry server, client case review program, and commercially available cloud-based image viewing system. In the pilot test, we used 30 cases of low-dose abdomen computed tomography for the diagnosis of acute appendicitis. In each case, a trainee was required to navigate through the images and submit answers to the case questions. The trainee was then given the correct answers and key images, as well as the image dataset with annotations on the appendix. After evaluation of all cases, the system displayed the diagnostic accuracy and average review time, and the trainee was asked to reassess the failed cases. The pilot system was deployed successfully in a hands-on workshop course. We developed an online radiology case review system that allows interactive navigation of volumetric image datasets using advanced visualization techniques

  18. Development of an online radiology case review system featuring interactive navigation of volumetric image datasets using advanced visualization techniques

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Hyun Kyung; Kim, Boh Kyoung; Jung, Ju Hyun; Kang, Heung Sik; Lee, Kyoung Ho [Dept. of Radiology, Seoul National University Bundang Hospital, Seongnam (Korea, Republic of); Woo, Hyun Soo [Dept. of Radiology, SMG-SNU Boramae Medical Center, Seoul (Korea, Republic of); Jo, Jae Min [Dept. of Computer Science and Engineering, Seoul National University, Seoul (Korea, Republic of); Lee, Min Hee [Dept. of Radiology, Soonchunhyang University Bucheon Hospital, Bucheon (Korea, Republic of)

    2015-11-15

    To develop an online radiology case review system that allows interactive navigation of volumetric image datasets using advanced visualization techniques. Our Institutional Review Board approved the use of the patient data and waived the need for informed consent. We determined the following system requirements: volumetric navigation, accessibility, scalability, undemanding case management, trainee encouragement, and simulation of a busy practice. The system comprised a case registry server, client case review program, and commercially available cloud-based image viewing system. In the pilot test, we used 30 cases of low-dose abdomen computed tomography for the diagnosis of acute appendicitis. In each case, a trainee was required to navigate through the images and submit answers to the case questions. The trainee was then given the correct answers and key images, as well as the image dataset with annotations on the appendix. After evaluation of all cases, the system displayed the diagnostic accuracy and average review time, and the trainee was asked to reassess the failed cases. The pilot system was deployed successfully in a hands-on workshop course. We developed an online radiology case review system that allows interactive navigation of volumetric image datasets using advanced visualization techniques.

  19. Navigation studies based on the ubiquitous positioning technologies

    Science.gov (United States)

    Ye, Lei; Mi, Weijie; Wang, Defeng

    2007-11-01

    This paper summarized the nowadays positioning technologies, such as absolute positioning methods and relative positioning methods, indoor positioning and outdoor positioning, active positioning and passive positioning. Global Navigation Satellite System (GNSS) technologies were introduced as the omnipresent out-door positioning technologies, including GPS, GLONASS, Galileo and BD-1/2. After analysis of the shortcomings of GNSS, indoor positioning technologies were discussed and compared, including A-GPS, Cellular network, Infrared, Electromagnetism, Computer Vision Cognition, Embedded Pressure Sensor, Ultrasonic, RFID (Radio Frequency IDentification), Bluetooth, WLAN etc.. Then the concept and characteristics of Ubiquitous Positioning was proposed. After the ubiquitous positioning technologies contrast and selection followed by system engineering methodology, a navigation system model based on Incorporate Indoor-Outdoor Positioning Solution was proposed. And this model was simulated in the Galileo Demonstration for World Expo Shanghai project. In the conclusion, the prospects of ubiquitous positioning based navigation were shown, especially to satisfy the public location information acquiring requirement.

  20. Evaluation on usefulness of stereotactic radio surgery using Fraxion system

    International Nuclear Information System (INIS)

    Kim, Tae Won; Park, Kwang Woo; Ha, Jin Sook; Jeon, Mi Jin; Cho, Yoon Jin; Kim, Sei Joon; Kim, Jong Dae; Shin, Dong Bong

    2014-01-01

    We evaluated the usefulness of Fraxion system and s-thermoplastic mask by analyzing setup error when stereotactic radiousurgery (SRS) was treated for brain metastasis. 6 patients who received definite diagnosis as brain metastasis between May 2014 and October 2014 were selected. 3 patients were immobilized s-thermoplastic mask and mouthpiece (group1), while Fraxion system was used for the other 3 patients (group 2). Cone Beam Computerized Tomography (CBCT) scan was acquired to register planning CT scan. The registration offset was compared for each group. We compared and reported the errors using maximum, minimum, mean, and standard deviation of registration offsets. Furthermore, We used the same method as patient specific quality assurance to verify absorbed dose of PTV. The setup error which is registration offset was reduced 83% in x, 40% in y, and 92% in z-direction when Fraxion system was used compared to the case of using s-thermoplastic mask and mouthpiece. In addition, using Fraxion system showed improved results in rotational components, pitch (rotation along x-axis), roll (y), and yaw (z) which were reduced 64, 88, and 87% respectively compared to the case of using s-thermoplastic mask and mouthpiece. In dosimetry results, when sthermoplastic mask and mouthpiece used, absorbed dose was reduce 83% compared to before and after registration. However, using Fraxion system showed only 1.9%. All percentage were calculated with respect to average value. Using Fraxion system including mouthpiece, Fraxion frame, front piece, and thermoplastic mask, showed better repeatability and precision compared to using s-thermoplastic mask and mouthpiece, which is consequently considered as more improved immobilization system