Framework for teleoperated microassembly systems

Science.gov (United States)

Reinhart, Gunther; Anton, Oliver; Ehrenstrasser, Michael; Patron, Christian; Petzold, Bernd

2002-02-01

Manual assembly of minute parts is currently done using simple devices such as tweezers or magnifying glasses. The operator therefore requires a great deal of concentration for successful assembly. Teleoperated micro-assembly systems are a promising method for overcoming the scaling barrier. However, most of today's telepresence systems are based on proprietary and one-of-a-kind solutions. Frameworks which supply the basic functions of a telepresence system, e.g. to establish flexible communication links that depend on bandwidth requirements or to synchronize distributed components, are not currently available. Large amounts of time and money have to be invested in order to create task-specific teleoperated micro-assembly systems from scratch. For this reason, an object-oriented framework for telepresence systems that is based on CORBA as a common middleware was developed at the Institute for Machine Tools and Industrial Management (iwb). The framework is based on a distributed architectural concept and is realized in C++. External hardware components such as haptic, video or sensor devices are coupled to the system by means of defined software interfaces. In this case, the special requirements of teleoperation systems have to be considered, e.g. dynamic parameter settings for sensors during operation. Consequently, an architectural concept based on logical sensors has been developed to achieve maximum flexibility and to enable a task-oriented integration of hardware components.

Power and signal transmission for mobile teleoperated systems

International Nuclear Information System (INIS)

Morris, A.C. Jr.; Hamel, W.R.

1986-01-01

Appropriate means must be furnished for supplying power and for sending controlling commands to mobile teleoperated systems. This paper describes a number of umbilical, onboard, and wireless systems used in transmitting power that are available for mobile teleoperator services. The pros and cons of selecting appropriate methods from a list of possible communication systems (wired, fiber optic, and radio frequency) are also examined. Moreover, hybrid systems combining wireless power transmissions with command-information signals are also possible. 20 refs., 6 figs., 1 tab

Passive impedance-based second-order sliding mode control for non-linear teleoperators

Directory of Open Access Journals (Sweden)

Luis G García-Valdovinos

2017-02-01

Full Text Available Bilateral teleoperation systems have attracted significant attention in the last decade mainly because of technological advancements in both the communication channel and computers performance. In addition, non-linear multi-degree-of-freedom bilateral teleoperators along with state observers have become an open research area. In this article, a model-free exact differentiator is used to estimate the full state along with a chattering-free second-order sliding mode controller to guarantee a robust impedance tracking under both constant and an unknown time delay of non-linear multi-degree-of-freedom robots. The robustness of the proposed controller is improved by introducing a change of coordinates in terms of a new nominal reference similar to that used in adaptive control theory. Experimental results that validate the predicted behaviour are presented and discussed using a Phantom Premium 1.0 as the master robot and a Catalyst-5 virtual model as the slave robot. The dynamics of the Catalyst-5 system is solved online.

Control issues for a hydraulically powered dissimilar teleoperated system

International Nuclear Information System (INIS)

Jansen, J.F.; Kress, R.L.

1995-01-01

This paper will address two issues associated with the implementation of a hydraulically powered dissimilar master-slave teleoperated system. These issues are the overall system control architecture and the design of robust hydraulic servo controllers for the position control problem. Finally, a discussion of overall system performance on an actual teleoperated system will be presented. (Schilling's Titan II hydraulic manipulators are the slave manipulators and the master manipulators are from the Oak Ridge National Laboratory-developed Advanced Servo Manipulator.)

A Ground-Based Validation System of Teleoperation for a Space Robot

Directory of Open Access Journals (Sweden)

Xueqian Wang

2012-10-01

Full Text Available Teleoperation of space robots is very important for future on-orbit service. In order to assure the task is accomplished successfully, ground experiments are required to verify the function and validity of the teleoperation system before a space robot is launched. In this paper, a ground-based validation subsystem is developed as a part of a teleoperation system. The subsystem is mainly composed of four parts: the input verification module, the onboard verification module, the dynamic and image workstation, and the communication simulator. The input verification module, consisting of hardware and software of the master, is used to verify the input ability. The onboard verification module, consisting of the same hardware and software as the onboard processor, is used to verify the processor's computing ability and execution schedule. In addition, the dynamic and image workstation calculates the dynamic response of the space robot and target, and generates emulated camera images, including the hand-eye cameras, global-vision camera and rendezvous camera. The communication simulator provides fidelity communication conditions, i.e., time delays and communication bandwidth. Lastly, we integrated a teleoperation system and conducted many experiments on the system. Experiment results show that the ground system is very useful for verified teleoperation technology.

Operation Modes and Control Schemes for Internet-Based Teleoperation System with Time Delay

Institute of Scientific and Technical Information of China (English)

曾庆军; 宋爱国

2003-01-01

Teleoperation system plays an important role in executing task under hazard environment. As the computer networks such as the Internet are being used as the communication channel of teleoperation system, varying time delay causes the overall system unstable and reduces the performance of transparency. This paper proposed twelve operation modes with different control schemes for teleoperation on the Internet with time delay. And an optimal operation mode with control scheme was specified for teleoperation with time delay, based on the tradeoff between passivity and transparency properties. It experimentally confirmed the validity of the proposed optimal mode and control scheme by using a simple one DOF master-slave manipulator system.

Status of the Advanced Teleoperation Project in the French A.R.A. program

International Nuclear Information System (INIS)

Andre, G.; Fournier, R.

1987-01-01

This paper reports the research and development work carried out in the French advanced teleoperation project. The successful achievement of significant progress, in recent years, allows to considerably advance the state of the art so that it objectively constitutes the foundation of a new generation of remote systems. After briefly recalling the organization of this project, the authors outline the basic concepts related to the evolution of teleoperation with regard to the notions of flexibility, adaptivity, autonomy, transparency. The authors present the overall architecture of the computer aided teleoperation system. The following sections deal with fundamental studies which have been realized and key subsystems which have been developed. The authors emphasize on the computer control system which includes: generalized bilateral control and supervisory control. Secondly, they underline the role of sophisticated technologies: sensory system, computer graphics. . ., for generating adaptive control functions and for providing new interfaces. Thirdly, they describe the integrated experimental site and, a set of generic experiments in nuclear applications. The paper ends with future perspectives

Power and signal transmission for mobile teleoperated systems

International Nuclear Information System (INIS)

Morris, A.C. Jr.; Hamel, W.R.

1985-01-01

Appropriate means must be furnished for supplying power and for sending controlling commands to mobile teleoperated systems. Because a sizable number of possibilities are available for such applications, methods used in designing both the power and communications systems built into mobile vehicles that serve in radiological emergencies must be carefully selected. This paper describes a number of umbilical, on-board, and wireless systems used in tranmitting power that are available for mobile teleoperator services. The pros and cons of selecting appropriate methods from a list of possible communication systems (wired, fiber optic, and radio frequency) are also examined. Moreover, hybrid systems combining wireless power transmissions with command-information signals are also possible

A Generalized Visual Aid System for Teleoperation Applied to Satellite Servicing

Directory of Open Access Journals (Sweden)

Guoliang Zhang

2014-02-01

Full Text Available This paper presents the latest results of a newly developed visual aid system for direct teleoperation. This method is extended to visual control to make an efficient teleoperation system by combining direct teleoperation and automatic control. On the one hand, an operator can conduct direct teleoperation with 3D graphic prediction simulation established by the VR technique. In order to remove inconsistencies between the virtual and real environments, a practical model-matching method is investigated. On the other hand, to realize real-time visual servoing control, a particular object recognition and pose estimation algorithm based on polygonal approximation is investigated to ensure a low computational cost for image processing. To avoid undesired forces involved in contact operation, 3D visual servoing incorporating a compliant control based on impedance control is developed. Finally, in a representative laboratory environment, a typical satellite servicing experiment is carried out based on this combined system. Experimental results demonstrate the feasibility and the effectiveness of the proposed method.

DESIGN AND CONSTRUCTION OF A FORCE-REFLECTING TELEOPERATION SYSTEM

Energy Technology Data Exchange (ETDEWEB)

M.A. Ebadian, Ph.D.

1999-01-01

For certain applications, such as space servicing, undersea operations, and hazardous material handling tasks in nuclear reactors, the environments can be uncertain, complex, and hazardous. Lives may be in danger if humans were to work under these conditions. As a result, a man-machine system--a teleoperator system--has been developed to work in these types of environments. In a typical teleoperator system, the actual system operates at a remote site; the operator located away from this system usually receives visual information from a video image and/or graphical animation on the computer screen. Additional feedback, such as aural and force information, can significantly enhance performance of the system. Force reflection is a type of feedback in which forces experienced by the remote manipulator are fed back to the manual controller. Various control methods have been proposed for implementation on a teleoperator system. In order to examine different control schemes, a one Degree-Of-Freedom (DOF) Force-Reflecting Manual Controller (FRMC) is constructed and integrated into a PC. The system parameters are identified and constructed as a mathematical model. The Proportional-Integral-Derivative (PID) and fuzzy logic controllers are developed and tested experimentally. Numerical simulation results obtained from the mathematical model are compared with those of experimental data for both types of controllers. In addition, the concept of a telesensation system is introduced. A telesensation system is an advanced teleoperator system that attempts to provide the operator with sensory feedback. In this context, a telesensation system integrates the use of a Virtual Reality (VR) unit, FRMC, and Graphical User Interface (GUI). The VR unit is used to provide the operator with a 3-D visual effect. Various commercial VR units are reviewed and features compared for use in a telesensation system. As for the FRMC, the conceptual design of a 3-DOF FRMC is developed in an effort to

DESIGN AND CONSTRUCTION OF A FORCE-REFLECTING TELEOPERATION SYSTEM

International Nuclear Information System (INIS)

Ebadian, M.A.

1999-01-01

For certain applications, such as space servicing, undersea operations, and hazardous material handling tasks in nuclear reactors, the environments can be uncertain, complex, and hazardous. Lives may be in danger if humans were to work under these conditions. As a result, a man-machine system--a teleoperator system--has been developed to work in these types of environments. In a typical teleoperator system, the actual system operates at a remote site; the operator located away from this system usually receives visual information from a video image and/or graphical animation on the computer screen. Additional feedback, such as aural and force information, can significantly enhance performance of the system. Force reflection is a type of feedback in which forces experienced by the remote manipulator are fed back to the manual controller. Various control methods have been proposed for implementation on a teleoperator system. In order to examine different control schemes, a one Degree-Of-Freedom (DOF) Force-Reflecting Manual Controller (FRMC) is constructed and integrated into a PC. The system parameters are identified and constructed as a mathematical model. The Proportional-Integral-Derivative (PID) and fuzzy logic controllers are developed and tested experimentally. Numerical simulation results obtained from the mathematical model are compared with those of experimental data for both types of controllers. In addition, the concept of a telesensation system is introduced. A telesensation system is an advanced teleoperator system that attempts to provide the operator with sensory feedback. In this context, a telesensation system integrates the use of a Virtual Reality (VR) unit, FRMC, and Graphical User Interface (GUI). The VR unit is used to provide the operator with a 3-D visual effect. Various commercial VR units are reviewed and features compared for use in a telesensation system. As for the FRMC, the conceptual design of a 3-DOF FRMC is developed in an effort to

Internet Teleoperation of a Robot with Streaming Buffer System under Varying Time Delays

Science.gov (United States)

Park, Jahng-Hyon; Shin, Wanjae

It is known that existence of irregular transmission time delay is a major bottleneck for application of advanced robot control schemes to internet telerobotic systems. In the internet teleoperation system, the irregular transmission time delay causes a critical problem, which includes instability and inaccuracy. This paper suggests a practical internet teleoperation system with streaming buffer system, which consists of a buffer, a buffer manager, and a control timer. The proposed system converts the irregular transmission time delay to a constant. So, the system effectively transmits the control input to a remote site to operate a robot stably and accurately. This feature enables short control input intervals. That means the entire system has a large control bandwidth. The validity of the proposed method is demonstrated by experiments of teleoperation from USC (University of Southern California in U. S.A.) to HYU (Hanyang Univ. in Korea) through the Internet. The proposed method is also demonstrated by experiments of teleoperation through the wireless internet.

An Adaptive Regulator for Space Teleoperation System in Task Space

Directory of Open Access Journals (Sweden)

Chao Ge

2014-01-01

Full Text Available The problem of the gravity information which can not be obtained in advance for bilateral teleoperation is studied. In outer space exploration, the gravity term changes with the position changing of the slave manipulator. So it is necessary to design an adaptive regulator controller to compensate for the unknown gravity signal. Moreover, to get a more accurate position tracking performance, the controller is designed in the task space instead of the joint space. Additionally, the time delay considered in this paper is not only time varying but also unsymmetrical. Finally, simulations are presented to show the effectiveness of the proposed approach.

Haptic Data Processing for Teleoperation Systems: Prediction, Compression and Error Correction

OpenAIRE

Lee, Jae-young

2013-01-01

This thesis explores haptic data processing methods for teleoperation systems, including prediction, compression, and error correction. In the proposed haptic data prediction method, unreliable network conditions, such as time-varying delay and packet loss, are detected by a transport layer protocol. Given the information from the transport layer, a Bayesian approach is introduced to predict position and force data in haptic teleoperation systems. Stability of the proposed method within stoch...

Bilateral teleoperation of underactuated unmanned aerial vehicles: The virtual slave concept

NARCIS (Netherlands)

Mersha, A.Y.; Stramigioli, Stefano; Carloni, Raffaella

In this paper, we present haptic teleoperation of underactuated unmanned aerial vehicles by providing a multidimensional generalization of the virtual slave concept. The proposed control architecture is composed of high-level and low-level controllers. The high-level controller commands the vehicle

Stability Control of Force-Reflected Nonlinear Multilateral Teleoperation System under Time-Varying Delays

Directory of Open Access Journals (Sweden)

Da Sun

2016-01-01

Full Text Available A novel control algorithm based on the modified wave-variable controllers is proposed to achieve accurate position synchronization and reasonable force tracking of the nonlinear single-master-multiple-slave teleoperation system and simultaneously guarantee overall system’s stability in the presence of large time-varying delays. The system stability in different scenarios of human and environment situations has been analyzed. The proposed method is validated through experimental work based on the 3-DOF trilateral teleoperation system consisting of three different manipulators. The experimental results clearly demonstrate the feasibility of the proposed algorithm to achieve high transparency and robust stability in nonlinear single-master-multiple-slave teleoperation system in the presence of time-varying delays.

The evolution of teleoperated manipulators at ORNL

International Nuclear Information System (INIS)

Kress, R.L.; Jansen, J.F.; Noakes, M.W.; Herndon, J.N.

1996-01-01

ORNL has made significant contributions to teleoperator and telerobotics technology for two decades and continues with an aggressive program today. Examples of past projects are: (1) the M2 servomanipulator, which was the first digitally controlled teleoperator; (2) the Advanced Servomanipulator (ASM), which was the first remotely maintainable teleoperator; (3) the CESARm/Kraft dissimilar teleoperated system; and (4) the Laboratory Telerobotic Manipulator (LTM), a 7-Degree-of-Freedom (7-DOF) telerobot built as a prototype for work in space. More recently, ORNL has become heavily involved with Environmental Restoration and Waste Management (ERWM) robotics programs funded by the Department of Energy (DOE). The ERWM program requires high payloads and high dexterity. As a result, a hydraulically actuated, dual-arm system comprised of two 6-DOF arms mounted on a 5-DOF base has been constructed and is being used today for various research tasks and for decontamination and dismantlement activities. All of these teleoperated manipulator systems build upon the experiences gained throughout the almost two decades of development. Each system incorporates not only the latest technology in computers, sensors, and electronics, but each new . system also adds at least one new feature to the technologies already developed and demonstrated in the previous system(s). As a result of this process, a serious study of these manipulator systems is a study in the evolution of teleoperated manipulator the systems in general. This provides insight not only into the research and development paths chosen in the past, but also into the appropriate directions for future teleoperator and telerobotics research. This paper examines each of the teleoperated/telerobotic systems developed at ORNL, summarizes their features and capabilities, examines the state of the most current telerobotic system (the Dual Arm Work Module), PM provides direction for a Next Generation Telerobotic Manipulator system

Switching robust control synthesis for teleoperation via dwell time conditions

NARCIS (Netherlands)

López Martínez, C.A.; van de Molengraft, M.J.G.; Steinbuch, M.; Auvray, M.; Duriez, C.

2014-01-01

Control design for bilateral teleoperation is still an open problem, given that it is desirable to meet a proper balance in the inherent trade-off between transparency and stability. We propose the use of switching robust control, in which smooth switching among controllers is achieved by the

Teleoperation system using Asynchronous transfer mode, ATM network

International Nuclear Information System (INIS)

Mohd Dani Baba; A Nasoruddin Mohamad

1999-01-01

This paper examines the application of Asynchronous Transfer Mode (ATM) in a distributed industrial environment such as in teleoperation, which performs real time control manipulation from a remote location. In our study, two models of teleoperation are proposed; the first model is a point to point connection and the second model is through an ATM network. The performance results are analysed as to determine whether the two models can support the teleoperation traffics via simulation using commercial software design tool. (Author)

An Intuitive Robot Teleoperation System for Nuclear Power Plant Decommissioning

International Nuclear Information System (INIS)

Lee, Chang-hyuk; Gu, Taehyeong; Lee, Kyung-min; Ye, Sung-Joon; Bang, Young-bong

2017-01-01

A robot teleoperation system consists of a master device and a slave robot. The master device senses human intention and delivers it to the salve robot. A haptic device and an exoskeletal robot are widely used as the master device. The slave robot carries out operations delivered by the master device. It should guarantee enough degree of freedom (DOF) to perform the instructed operation and mobility in the environment inside the nuclear plant, such as flat surfaces and stairs. A 7-DOF robotic arm is commonly used as the slave device. This paper proposed a robot teleoperation system for nuclear power plant decommissioning. It discussed an experiment that was performed to validate the system's usability. The operator wearing the exoskeletal master device at the master site controlled the slave robot enabling it to move on a flat surface, climb/descend stairs, and move obstacles. The proposed robot teleoperation system can also be used in hazardous working environments where the use of such robots would be beneficial to human health and safety. In the future, research studies on the protection against radiation that damages the slave robot should be conducted.

Switching-based Mapping and Control for Haptic Teleoperation of Aerial Robots

NARCIS (Netherlands)

Mersha, A.Y.; Stramigioli, Stefano; Carloni, Raffaella

2012-01-01

This paper deals with the bilateral teleoperation of underactuated aerial robots by means of a haptic interface. In particular, we propose a switching-based state mapping and control algorithm between a rate-based passive controller, which addresses the workspace incompatibility between the master

The Development of radiation hardened tele-robot system - Development of teleoperating technology using a universal master

Energy Technology Data Exchange (ETDEWEB)

Choi, Yong Je; Yang, Hyun Suk [Yonsei University, Seoul (Korea)

1999-04-01

A force-reflecting universal master for a teleoperating system has been designed and constructed, which can be used as an effective command input device for teleoperated robots. This report presents a full detail of the mechanism design and experiments related to the development of the force-reflecting masters. A real time virtual graphics display system which can be used as a powerful tool to predict any potential dangers and also to prevent an accident in advance has been developed and interfaced with the master. In order to transmit the force information of the slave to the operator effectively, the force-reflecting algorithm has been suggested and tested on the teleoperating system. The various master-slave systems have been tested in order to develop an efficient control algorithm for a teleoperating system with a force-reflecting master. A compliant device with the force/torque sensor capability has been also developed, which can be used as a passive position/force hybrid control device and as a sensor acquiring valid contact information of a slave with an environment. Experimental results showed that the developed teleoperating technology can be applied to a teleoperator system which interacts with the real environment. 21 refs., 103 figs., 2 tabs. (Author)

Advanced instrumentation and teleoperation

International Nuclear Information System (INIS)

Decreton, M.

1998-01-01

SCK-CEN's advanced instrumentation and teleoperation project aims at evaluating the potential of a telerobotic approach in a nuclear environment and, in particular, the use of remote-perception systems. Main achievements in 1997 in the areas of R and D on radiation tolerance for remote sensing, optical fibres and optical-fibre sensors, and computer-aided teleoperation are reported

Design of teleoperated robot system for nozzle dam maintenance in steam generator

International Nuclear Information System (INIS)

Kim, Chang-Hoi; Hwang, Suk-Young; Lee, Young-Gwang; Kim, Byung-Soo; Kim, Seung-Ho; Lee, Jong-Min

1994-01-01

The recent development of teleoperated manipulator system in KAERI is presented. The manipulator system is composed of master-slave arm and control system with VME based hierarchical structure. Supervisory control part with graphic workstation provides affluent visual information to human operator. This robot can be operated either in the teleoperation mode with master-slave or in the program mode running by computer system itself to enable installation or removal of nozzle dam appropriately within a water chamber of steam generator. Evaluation and analysis have been carried out to get optimal parameters of the robot. (author)

System for intelligent teleoperation research

International Nuclear Information System (INIS)

Orlando, N.E.

1983-01-01

The Automation Technology Branch of NASA Langley Research Center is developing a research capability in the field of artificial intelligence, particularly as applicable in teleoperator/robotics development for remote space operations. As a testbed for experimentation in these areas, a system concept has been developed and is being implemented. This system, termed DAISIE (Distributed Artificially Intelligent System for Interacting with the Environment), interfaces the key processes of perception, reasoning, and manipulation by linking hardware sensors and manipulators to a modular artificial intelligence (AI) software system in a hierarchical control structure. Verification experiments have been performed: one experiment used a blocksworld database and planner embedded in the DAISIE system to intelligently manipulate a simple physical environment; the other experiment implemented a joint-space collision avoidance algorithm. Continued system development is planned

Compact teleoperated laparoendoscopic single-site robotic surgical system: Kinematics, control, and operation.

Science.gov (United States)

Isaac-Lowry, Oran Jacob; Okamoto, Steele; Pedram, Sahba Aghajani; Woo, Russell; Berkelman, Peter

2017-12-01

To date a variety of teleoperated surgical robotic systems have been developed to improve a surgeon's ability to perform demanding single-port procedures. However typical large systems are bulky, expensive, and afford limited angular motion, while smaller designs suffer complications arising from limited motion range, speed, and force generation. This work was to develop and validate a simple, compact, low cost single site teleoperated laparoendoscopic surgical robotic system, with demonstrated capability to carry out basic surgical procedures. This system builds upon previous work done at the University of Hawaii at Manoa and includes instrument and endoscope manipulators as well as compact articulated instruments designed to overcome single incision geometry complications. A robotic endoscope holder was used for the base, with an added support frame for teleoperated manipulators and instruments fabricated mostly from 3D printed parts. Kinematics and control methods were formulated for the novel manipulator configuration. Trajectory following results from an optical motion tracker and sample task performance results are presented. Results indicate that the system has successfully met the goal of basic surgical functionality while minimizing physical size, complexity, and cost. Copyright © 2017 John Wiley & Sons, Ltd.

Assisted supervision of a computer aided tele-operation system

Energy Technology Data Exchange (ETDEWEB)

Le Bars, H; Gravez, P; Fournier, R

1994-12-31

This paper talks about Computer Aided Tele-operation (CAT) in dismantling and maintenance of nuclear plants. The current research orientations at CEA, basic concepts of the supervision assistance system and the realisation of a prototype are presented. (TEC). 3 refs., 4 figs.

Assisted supervision of a computer aided tele-operation system

International Nuclear Information System (INIS)

Le Bars, H.; Gravez, P.; Fournier, R.

1994-01-01

This paper talks about Computer Aided Tele-operation (CAT) in dismantling and maintenance of nuclear plants. The current research orientations at CEA, basic concepts of the supervision assistance system and the realisation of a prototype are presented. (TEC). 3 refs., 4 figs

A Study of Accuracy and Time Delay for Bilateral Master-Slave Industrial Robotic Arm Manipulator System

Directory of Open Access Journals (Sweden)

Mansor Nuratiqa Natrah

2018-01-01

Full Text Available Bilateral master-slave industrial robotic arm manipulator system is an advanced technology used to help human to interact with environments that are unreachable to human, due to its remoteness or perilous. The system has been used in different areas such as tele-surgery, autonomous tele-operation for sea and space operation and handling explosive or high radiation operation fields. It is beneficial both for science and society. Remarkably, the system is not common and generally used in Malaysia. Likewise, the number of research conducted that focused about this technology in our country manufacturing industry are not yet discovered and existent. The implementation of this bilateral manipulator system in an industrial robot could be useful for industrial imminent and development over our country and people, specifically for production yield size and human operative. Hence, the study of bilateral robotic arm manipulator system in an industrial robot and analyzation of its performance and time delay in 3 differ controllers will be discussed to attest the efficiency and its effectiveness on the said design system. The experiment conducted was on KUKA youBot arm in V-Rep simulation with three different controllers (P, PD, PID.

A design framework for teleoperators with kinesthetic feedback

Science.gov (United States)

Hannaford, Blake

1989-01-01

The application of a hybrid two-port model to teleoperators with force and velocity sensing at the master and slave is presented. The interfaces between human operator and master, and between environment and slave, are ports through which the teleoperator is designed to exchange energy between the operator and the environment. By computing or measuring the input-output properties of this two-port network, the hybrid two-port model of an actual or simulated teleoperator system can be obtained. It is shown that the hybrid model (as opposed to other two-port forms) leads to an intuitive representation of ideal teleoperator performace and applies to several teleoperator architectures. Thus measured values of the h matrix or values computed from a simulation can be used to compare performance with th ideal. The frequency-dependent h matrix is computed from a detailed SPICE model of an actual system, and the method is applied to a proposed architecture.

Mobile robot teleoperation system for plant inspection based on collecting and utilizing environment data

International Nuclear Information System (INIS)

Kawabata, Kuniaki; Watanabe, Nobuyasu; Asama, Hajime; Kita, Nobuyuki; Yang, Hai-quan

2004-01-01

This paper describes about development of a mobile robot teleoperation system for plant inspection. In our system, the robot is an agent for collecting the environment data and is also teleoperated by the operator utilizing such accumulated environment data which is displayed on the operation interface. The robot equips many sensors for detecting the state of the robot and the environment. Such redundant sensory system can be also utilized to collect the working environment data on-site while the robot is patrolling. Here, proposed system introduces the framework of collecting and utilizing environment data for adaptive plant inspection using the teleoperated robot. A view simulator is primarily aiming to facilitate evaluation of the visual sensors and algorithms and is also extended as the Environment Server, which is the core technology of the digital maintenance field for the plant inspection. In order to construct detailed seamless digital maintenance field mobile robotic technology is utilized to supply environment data to the server. The sensory system on the robot collect the environment data on-site and such collected data is uploaded to the Environment Server for compiling accurate digital environment data base. The robot operator also can utilize accumulated environment data by referring to the Environment Server. In this paper, we explain the concept of our teleoperation system based on collecting and utilizing environment data. Using developed system, inspection patrol experiments were attempted in the plant mock-up. Experimental results are shown by using an omnidirectional mobile robot with sensory system and the Environment Server. (author)

Development of a piezo-actuated micro-teleoperation system for cell manipulation.

Science.gov (United States)

Zareinejad, M; Rezaei, S M; Abdullah, A; Shiry Ghidary, S

2009-03-01

Intracytoplasmic sperm injection (ICSI) requires long training and has low success rates, primarily due to poor control over the injection force. Making force feedback available to the operator will improve the success rate of the injection task. A macro-micro-teleoperation system bridges the gap between the task performed at the micro-level and the macroscopic movements of the operator. The teleoperation slave manipulator should accurately position a needle to precisely penetrate a cell membrane. Piezoelectric actuators are widely used in micromanipulation applications; however, hysteresis non-linearity limits the accuracy of these actuators. This paper presents a novel approach for utilizing a piezoelectric nano-stage as slave manipulator of a teleoperation system. The Prandtl-Ishlinskii (PI) model is used to model actuator hysteresis in a feedforward scheme to cancel out this non-linearity. To deal with the influence of parametric uncertainties, unmodelled dynamics and PI identification error, a perturbation term is added to the slave model and applies a sliding mode-based impedance control with perturbation estimation. The stability of entire system is guaranteed by Llewellyn's absolute stability criterion. The performance of the proposed controller was investigated through experiments for cell membrane penetration. The experimental results verified the accurate position tracking in free motion and simultaneous position and force tracking in contact with a low stiffness environment.

Towards multi-platform software architecture for Collaborative Teleoperation

Science.gov (United States)

Domingues, Christophe; Otmane, Samir; Davesne, Frederic; Mallem, Malik

2009-03-01

Augmented Reality (AR) can provide to a Human Operator (HO) a real help in achieving complex tasks, such as remote control of robots and cooperative teleassistance. Using appropriate augmentations, the HO can interact faster, safer and easier with the remote real world. In this paper, we present an extension of an existing distributed software and network architecture for collaborative teleoperation based on networked human-scaled mixed reality and mobile platform. The first teleoperation system was composed by a VR application and a Web application. However the 2 systems cannot be used together and it is impossible to control a distant robot simultaneously. Our goal is to update the teleoperation system to permit a heterogeneous collaborative teleoperation between the 2 platforms. An important feature of this interface is based on the use of different Virtual Reality platforms and different Mobile platforms to control one or many robots.

Towards multi-platform software architecture for Collaborative Teleoperation

International Nuclear Information System (INIS)

Domingues, Christophe; Otmane, Samir; Davesne, Frederic; Mallem, Malik

2009-01-01

Augmented Reality (AR) can provide to a Human Operator (HO) a real help in achieving complex tasks, such as remote control of robots and cooperative teleassistance. Using appropriate augmentations, the HO can interact faster, safer and easier with the remote real world. In this paper, we present an extension of an existing distributed software and network architecture for collaborative teleoperation based on networked human-scaled mixed reality and mobile platform. The first teleoperation system was composed by a VR application and a Web application. However the 2 systems cannot be used together and it is impossible to control a distant robot simultaneously. Our goal is to update the teleoperation system to permit a heterogeneous collaborative teleoperation between the 2 platforms. An important feature of this interface is based on the use of different Virtual Reality platforms and different Mobile platforms to control one or many robots.

Two-Channel Transparency-Optimized Control Architectures in Bilateral Teleoperation With Time Delay.

Science.gov (United States)

Kim, Jonghyun; Chang, Pyung Hun; Park, Hyung-Soon

2013-01-01

This paper introduces transparency-optimized control architectures (TOCAs) using two communication channels. Two classes of two-channel TOCAs are found, thereby showing that two channels are sufficient to achieve transparency. These TOCAs achieve a greater level of transparency but poorer stability than three-channel TOCAs and four-channel TOCAs. Stability of the two-channel TOCAs has been enhanced while minimizing transparency degradation by adding a filter; and a combined use of the two classes of two-channel TOCAs is proposed for both free space and constrained motion, which involve switching between two TOCAs for transition between free space and constrained motions. The stability condition of the switched teleoperation system is derived for practical applications. Through the one degree-of-freedom (DOF) experiment, the proposed two-channel TOCAs were shown to operate stably, while achieving better transparency under time delay than the other TOCAs.

Semiautonomous teleoperation system with vision guidance

Science.gov (United States)

Yu, Wai; Pretlove, John R. G.

1998-12-01

This paper describes the ongoing research work on developing a telerobotic system in Mechatronic Systems and Robotics Research group at the University of Surrey. As human operators' manual control of remote robots always suffer from reduced performance and difficulties in perceiving information from the remote site, a system with a certain level of intelligence and autonomy will help to solve some of these problems. Thus, this system has been developed for this purpose. It also serves as an experimental platform to test the idea of using the combination of human and computer intelligence in teleoperation and finding out the optimum balance between them. The system consists of a Polhemus- based input device, a computer vision sub-system and a graphical user interface which communicates the operator with the remote robot. The system description is given in this paper as well as the preliminary experimental results of the system evaluation.

Robot technology. Vol. 3B. Teleoperation and robotics: applications and technology

Energy Technology Data Exchange (ETDEWEB)

Vertut, J; Coiffet, P

1985-01-01

Teleoperation is concerned with the exploration and exploitation of of spaces which do not allow, because of their inaccessibility or hostility, direct access to man. This volume (Parts 2, 3 and 4) covers the contribution of computer science and automatic control to this technology. Part 2 includes a description of teleoperation systems followed by chapters on the operator substitution function by computer feedback to the operator. Part 3 has chapters on performance evaluation of teleoperation systems and the human operator in the teleoperation system. Part 4 is about applications of teleoperation in the nuclear industry, underwater, in space, in medicine, in industry and in security and civil protection. The nuclear applications include research and pilot facilities, reactor operation and maintenance, reactor decommissioning and dismantling and in emergencies, for example following a reactor accident. (U.K.).

Two-Channel Transparency-Optimized Control Architectures in Bilateral Teleoperation With Time Delay

Science.gov (United States)

Kim, Jonghyun; Chang, Pyung Hun; Park, Hyung-Soon

2013-01-01

This paper introduces transparency-optimized control architectures (TOCAs) using two communication channels. Two classes of two-channel TOCAs are found, thereby showing that two channels are sufficient to achieve transparency. These TOCAs achieve a greater level of transparency but poorer stability than three-channel TOCAs and four-channel TOCAs. Stability of the two-channel TOCAs has been enhanced while minimizing transparency degradation by adding a filter; and a combined use of the two classes of two-channel TOCAs is proposed for both free space and constrained motion, which involve switching between two TOCAs for transition between free space and constrained motions. The stability condition of the switched teleoperation system is derived for practical applications. Through the one degree-of-freedom (DOF) experiment, the proposed two-channel TOCAs were shown to operate stably, while achieving better transparency under time delay than the other TOCAs. PMID:23833548

Trust between man and machine in a teleoperation system

International Nuclear Information System (INIS)

Dassonville, I.; Jolly, D.; Desodt, A.M.

1996-01-01

The work we present deals with the trust of man in a teleoperation system. Trust is important because it is linked to stress which modifies human reliability. We are trying to quantify trust. In this paper, we'll present the theory of trust in relationships, and its extension for a man-machine system. Then, we explain the links between trust and human reliability. Then, we introduce our experimental process and the first results concerning selfconfidence

Robotics and tele-operation technology for applications in nuclear fields

International Nuclear Information System (INIS)

Kosuge, Kazuhiro; Hirata, Yasuhisa; Takeo, Koji

2002-01-01

In this article, we introduce available robotics and tele-operation technology for applications in Nuclear Fields. First, robotics technology for manipulation of a large object is introduced which has been experimentally applied to ITER Maintenance Robot. Then, transportation technology of a large object by multiple mobile robots is reviewed. At last, recent tele-operation technologies and a prototype tele-operation system, referred to as VISIT (Visual Interface System for Interactive Task-execution), is introduced. Several experimental results are also introduced. (author)

Mobile teleoperator remote sensing

International Nuclear Information System (INIS)

Hall, E.L.

1986-01-01

Sensing systems are an important element of mobile teleoperators and robots. This paper discusses certain problems and limitations of vision and other sensing systems with respect to operations in a radiological accident environment. Methods which appear promising for near-term improvements to sensor technology are described. 3 refs

Teleoperation and computer control of a backhoe/manipulator system

International Nuclear Information System (INIS)

Amazeen, C.A.; Bishop, S.S.

1987-01-01

Teleoperation of the U.S. Army's Small Emplacement Excavator (SEE) is now in the prototype stage of development. Initial work is directed towards remotely controlling the SEE backhoe attachment as well as a Belvoir Research, Development, and Engineering Center (BRDEC)-developed heavy-lift manipulator (HLM). The HLM is an alternate end effector for the backhoe. Primitive computer control of the backhoe, with a bucket as an end effector, has been achieved. This paper presents the current and planned system configurations and discusses system applications

Mobile teleoperator research at Savannah River Laboratory

International Nuclear Information System (INIS)

Byrd, J.S.

1985-01-01

A Robotics Technology Group was organized at Savannah River Laboratory to employ modern automation and robotics for applications at the Savannah River site. Several industrial robots have been installed in plant processes. Other robotics systems are under development in the laboratories, including mobile teleoperators for general remote tasks and emergency response operations. This paper discusses present work on a low-cost wheeled mobile vehicle, a modular light duty manipulator arm, a large gantry telerobot system, and a high technology six-legged walking robot with a teleoperated arm

Modeling Human Steering Behavior During Path Following in Teleoperation of Unmanned Ground Vehicles.

Science.gov (United States)

Mirinejad, Hossein; Jayakumar, Paramsothy; Ersal, Tulga

2018-04-01

This paper presents a behavioral model representing the human steering performance in teleoperated unmanned ground vehicles (UGVs). Human steering performance in teleoperation is considerably different from the performance in regular onboard driving situations due to significant communication delays in teleoperation systems and limited information human teleoperators receive from the vehicle sensory system. Mathematical models capturing the teleoperation performance are a key to making the development and evaluation of teleoperated UGV technologies fully simulation based and thus more rapid and cost-effective. However, driver models developed for the typical onboard driving case do not readily address this need. To fill the gap, this paper adopts a cognitive model that was originally developed for a typical highway driving scenario and develops a tuning strategy that adjusts the model parameters in the absence of human data to reflect the effect of various latencies and UGV speeds on driver performance in a teleoperated path-following task. Based on data collected from a human subject test study, it is shown that the tuned model can predict both the trend of changes in driver performance for different driving conditions and the best steering performance of human subjects in all driving conditions considered. The proposed model with the tuning strategy has a satisfactory performance in predicting human steering behavior in the task of teleoperated path following of UGVs. The established model is a suited candidate to be used in place of human drivers for simulation-based studies of UGV mobility in teleoperation systems.

Human factors activities in teleoperator development at the Oak Ridge National Laboratory

International Nuclear Information System (INIS)

Draper, J.V.; Herndon, J.N.

1986-01-01

The Consolidated Fuel Reprocessing Program (CFRP) at the Oak Ridge National Laboratory is developing advanced teleoperator systems for maintenance of future nuclear reprocessing facilities. Remote maintenance systems developed by the CFRP emphasize man-in-the-loop teleoperation. Consequently, human factors issues which affect teleoperator performance must be addressed. This papers surveys research and development activities carried out by the human factors group within the Remote Control Engineering Task of the CFRP

The Development of Radiation hardened tele-robot system - Development of artificial force reflection control for teleoperated mobile robots

Energy Technology Data Exchange (ETDEWEB)

Lee, Ju Jang; Hong, Sun Gi; Kang, Young Hoon; Kim, Min Soeng [Korea Advanced Institute of Science and Technology, Taejon (Korea)

1999-04-01

One of the most important issues in teleoperation is to provide the sense of telepresence so as to conduct the task more reliably. In particular, teleoperated mobile robots are needed to have some kinds of backup system when the operator is blind for remote situation owing to the failure of vision system. In the first year, the idea of artificial force reflection was researched to enhance the reliability of operation when the mobile robot travels on the plain ground. In the second year, we extend previous results to help the teleoperator even when the robot climbs stairs. Finally, we apply the developed control algorithms to real experiments. The artificial force reflection method has two modes; traveling on the plain ground and climbing stairs. When traveling on the plain ground, the force information is artificially generated by using the range data from the environment while generating the impulse force when climbing stairs. To verify the validity of our algorithm, we develop the simulator which consists of the joystick and the visual display system. Through some experiments using this system, we confirm the validity and effectiveness of our new idea of artificial force reflection in the teleoperated mobile robot. 11 refs., 30 figs. (Author)

Mechanical accessories for mobile teleoperators

International Nuclear Information System (INIS)

Feldman, M.J.; Herndon, J.N.

1985-01-01

The choice of optimum mechanical accessories for mobile teleoperators involves matching the criteria for emergency response with the available technology. This paper presents a general background to teleoperations, a potpourri of the manipulator systems available, and an argument for force reflecting manipulation. The theme presented is that the accomplishment of humanlike endeavors in hostile environments will be most successful when man model capabilities are utilized. The application of recent electronic technology to manipulator development has made new tools available to be applied to emergency response activities. The development activities described are products of the Consolidated Fuel Reprocessing Program at the Oak Ridge National Laboratory. 13 refs., 7 figs

The implications of force reflection for teleoperation in space

International Nuclear Information System (INIS)

Draper, J.V.; Herndon, J.N.; Moore, W.E.

1987-01-01

This paper reviews previous research on teleoperator force feedback and reports results of a testing program which assessed the impact of force reflection on teleoperator task performance. Force reflection is a type of force feedback in which the forces acting on the remote portion of the teleoperator are displayed to the operator by back-driving the master controller. The testing program compared three force reflection levels: 4 to 1 (four units of force on the slave produce one unit of force at the master controller), 1 to 1, and infinity to 1 (no force reflection). Time required to complete tasks, rate of occurrence of errors, the maximum force applied to tasks components, and variability in forces applied to components during completion of representative remote handling tasks were used as dependent variables. Operators exhibited lower error rates, lower peak forces, and more consistent application of forces using force reflection than they did without it. These data support the hypothesis that force reflection provides useful information for teleoperator users. The earlier literature and the results of the experiment are discussed in terms of their implications for space-based teleoperator systems. The discussion describes the impact of force reflection on task completion performance and task strategies, as suggested by the literature. It is important to understand the trade-offs involved in using telerobotic systems with and without force reflection. Force-reflecting systems are typically more expensive (in mass, volume, and price per unit), but they reduce mean time to repair and may be safer to use, compared to systems without force reflection

Social Inclusion of Senior Citizens by a Teleoperated Android

DEFF Research Database (Denmark)

Yamazaki, Ryuji; Nishio, Shuichi; Ishiguro, Hiroshi

As populations continue to age, there is a growing need for assistive technologies that help senior citizens maintain their autonomy and enjoy their lives. We explore the potential of teleoperated androids, which are embodied telecommunication media with humanlike appearances. Our exploratory study...... focused on the social aspects of Telenoid, a teleoperated android designed as a minimalistic human, which might facilitate communica- tion between senior citizens and its operators. We con- ducted cross-cultural field trials in Japan and Denmark by introducing Telenoid into care facilities and the pri......- vate homes of seniors to observe how they responded to it. In Japan, we set up a teleoperation system in an elemen- tary school and investigated how it shaped communica- tion through the internet between the elderly in a care facility and the children who acted as teleoperators. In both countries...

Telepresence and teleoperation

International Nuclear Information System (INIS)

Parsons, H.M.

1990-01-01

Some developers of mobile teleoperators for remote systems have been emphasizing telepresence as an important design consideration. This paper discusses what that term means and what it implies for human/machine interfaces from a human factors viewpoint. In general, telepresence means designing a control station's equipment so an operator has a sense of presence at the remote manipulator or vehicle being controlled

Teleoperation over low bandwidth communication links

International Nuclear Information System (INIS)

Fryer, R.J.; Mair, G.M.; Clark, N.; Heng, J.

1996-01-01

Teleoperation is well established for many areas of hazardous environment working. Where such environments are well structured and contained, such as within a working plant, communications bandwidths need not be a constraining factor. However where the worksite is remote, large, poorly structured or damaged communications rapidly become a critical factor in the efficient deployment and use of teleoperation equipment. The paper justifies and describes means which we are exploring to reduce the required communications bandwidth for teleoperation whist retaining full functionality. Techniques involved include incorporation of local intelligence at the worksite, with bandwidth devoted to high-level up-link control signals and down-link feedback, and the use of highly compressed video feeding 'virtual reality type' HMDs to provide maximum system transparency for the operator. The work is drawing on previous experience with an 'anthropomorphic robot heat' for telepresence work, and proprietary algorithms capable of compressing full colour video to standard telephone modem data rates. (Author)

Joining teleoperation with robotics for advanced manipulation in hostile environments

International Nuclear Information System (INIS)

Martin, H.L.; Hamel, W.R.

1984-01-01

Manipulators have been used for many years to perform remote handling tasks in hazardous environments. The development history of teleoperators is reviewed, and applications around the world are summarized. The effect of computer supervisory control is discussed, and similarities between robots and teleoperator research activities are delineated. With improved control strategies and system designs, combination of positive attributes of robots with teleoperators will lead to advanced machines capable of autonomy in unstructured environments. This concept of a telerobot is introduced as a goal for future activities

Fuzzy Logic Supervised Teleoperation Control for Mobile Robot

Institute of Scientific and Technical Information of China (English)

无

2008-01-01

The supervised teleoperation control is presented for a mobile robot to implement the tasks by using fuzzy logic. The teleoperation control system includes joystick based user interaction mechanism, the high level instruction set and fuzzy logic behaviors integrated in a supervised autonomy teleoperation control system for indoor navigation. These behaviors include left wall following, right wall following, turn left, turn right, left obstacle avoidance, right obstacle avoidance and corridor following based on ultrasonic range finders data. The robot compares the instructive high level command from the operator and relays back a suggestive signal back to the operator in case of mismatch between environment and instructive command. This strategy relieves the operator's cognitive burden, handle unforeseen situations and uncertainties of environment autonomously. The effectiveness of the proposed method for navigation in an unstructured environment is verified by experiments conducted on a mobile robot equipped with only ultrasonic range finders for environment sensing.

Pseudo-Haptic Feedback in Teleoperation.

Science.gov (United States)

Neupert, Carsten; Matich, Sebastian; Scherping, Nick; Kupnik, Mario; Werthschutzky, Roland; Hatzfeld, Christian

2016-01-01

In this paper, we develop possible realizations of pseudo-haptic feedback in teleoperation systems based on existing works for pseudo-haptic feedback in virtual reality and the intended applications. We derive four potential factors affecting the performance of haptic feedback (calculation operator, maximum displacement, offset force, and scaling factor), which are analyzed in three compliance identification experiments. First, we analyze the principle usability of pseudo-haptic feedback by comparing information transfer measures for teleoperation and direct interaction. Pseudo-haptic interaction yields well above-chance performance, while direct interaction performs almost perfectly. In order to optimize pseudo-haptic feedback, in the second study we perform a full-factorial experimental design with 36 subjects performing 6,480 trials with 36 different treatments. Information transfer ranges from 0.68 bit to 1.72 bit in a task with a theoretical maximum of 2.6 bit, with a predominant effect of the calculation operator and a minor effect of the maximum displacement. In a third study, short- and long-term learning effects are analyzed. Learning effects regarding the performance of pseudo-haptic feedback cannot be observed for single-day experiments. Tests over 10 days show a maximum increase in information transfer of 0.8 bit. The results show the feasibility of pseudo-haptic feedback for teleoperation and can be used as design basis for task-specific systems.

Human Machine Interfaces for Teleoperators and Virtual Environments Conference

Science.gov (United States)

1990-01-01

In a teleoperator system the human operator senses, moves within, and operates upon a remote or hazardous environment by means of a slave mechanism (a mechanism often referred to as a teleoperator). In a virtual environment system the interactive human machine interface is retained but the slave mechanism and its environment are replaced by a computer simulation. Video is replaced by computer graphics. The auditory and force sensations imparted to the human operator are similarly computer generated. In contrast to a teleoperator system, where the purpose is to extend the operator's sensorimotor system in a manner that facilitates exploration and manipulation of the physical environment, in a virtual environment system, the purpose is to train, inform, alter, or study the human operator to modify the state of the computer and the information environment. A major application in which the human operator is the target is that of flight simulation. Although flight simulators have been around for more than a decade, they had little impact outside aviation presumably because the application was so specialized and so expensive.

Implementation and design of a teleoperation system based on a VMEBUS/68020 pipelined architecture

Science.gov (United States)

Lee, Thomas S.

1989-01-01

A pipelined control design and architecture for a force-feedback teleoperation system that is being implemented at the Jet Propulsion Laboratory and which will be integrated with the autonomous portion of the testbed to achieve share control is described. At the local site, the operator sees real-time force/torque displays and moves two 6-degree of freedom (dof) force-reflecting hand-controllers as his hands feel the contact force/torques generated at the remote site where the robots interact with the environment. He also uses a graphical user menu to monitor robot states and specify system options. The teleoperation software is written in the C language and runs on MC68020-based processor boards in the VME chassis, which utilizes a real-time operating system; the hardware is configured to realize a four-stage pipeline configuration. The environment is very flexible, such that the system can easily be configured as a stand-alone facility for performing independent research in human factors, force control, and time-delayed systems.

Design and implementation of visual-haptic assistive control system for virtual rehabilitation exercise and teleoperation manipulation.

Science.gov (United States)

Veras, Eduardo J; De Laurentis, Kathryn J; Dubey, Rajiv

2008-01-01

This paper describes the design and implementation of a control system that integrates visual and haptic information to give assistive force feedback through a haptic controller (Omni Phantom) to the user. A sensor-based assistive function and velocity scaling program provides force feedback that helps the user complete trajectory following exercises for rehabilitation purposes. This system also incorporates a PUMA robot for teleoperation, which implements a camera and a laser range finder, controlled in real time by a PC, were implemented into the system to help the user to define the intended path to the selected target. The real-time force feedback from the remote robot to the haptic controller is made possible by using effective multithreading programming strategies in the control system design and by novel sensor integration. The sensor-based assistant function concept applied to teleoperation as well as shared control enhances the motion range and manipulation capabilities of the users executing rehabilitation exercises such as trajectory following along a sensor-based defined path. The system is modularly designed to allow for integration of different master devices and sensors. Furthermore, because this real-time system is versatile the haptic component can be used separately from the telerobotic component; in other words, one can use the haptic device for rehabilitation purposes for cases in which assistance is needed to perform tasks (e.g., stroke rehab) and also for teleoperation with force feedback and sensor assistance in either supervisory or automatic modes.

Workload, flow, and telepresence during teleoperation

Energy Technology Data Exchange (ETDEWEB)

Draper, J.V. [Oak Ridge National Lab., TN (United States); Blair, L.M. [Human Machine Interfaces, Inc., Knoxville, TN (United States)

1996-04-01

There is much speculation about the relations among workload, flow, telepresence, and performance during teleoperation, but few data that provide evidence concerning them. This paper presents results an investigation conducted during completion of a pipe cutting task using a teleoperator at ORNL. Results show support for the hypothesis that telepresence is related to expenditure of attentional resources, and some support for the hypothesis that telepresence is related to flow. The discussion examines the results from an attentional resources perspective on teleoperation.

Workload, flow, and telepresence during teleoperation

International Nuclear Information System (INIS)

Draper, J.V.; Blair, L.M.

1996-01-01

There is much speculation about the relations among workload, flow, telepresence, and performance during teleoperation, but few data that provide evidence concerning them. This paper presents results an investigation conducted during completion of a pipe cutting task using a teleoperator at ORNL. Results show support for the hypothesis that telepresence is related to expenditure of attentional resources, and some support for the hypothesis that telepresence is related to flow. The discussion examines the results from an attentional resources perspective on teleoperation

Teleoperators: Man's Machine Partners

Energy Technology Data Exchange (ETDEWEB)

Corliss, William R.

1972-01-01

This booklet is about teleoperators, a class of machines that augment man rather than replace him. Teleoperators have the ability to add to man's strength, his reach, and his ability to work in hostile environments.

A CORBA-Based Control Architecture for Real-Time Teleoperation Tasks in a Developmental Humanoid Robot

Directory of Open Access Journals (Sweden)

Hanafiah Yussof

2011-06-01

Full Text Available This paper presents the development of new Humanoid Robot Control Architecture (HRCA platform based on Common Object Request Broker Architecture (CORBA in a developmental biped humanoid robot for real-time teleoperation tasks. The objective is to make the control platform open for collaborative teleoperation research in humanoid robotics via the internet. Meanwhile, to generate optimal trajectory generation in bipedal walk, we proposed a real time generation of optimal gait by using Genetic Algorithms (GA to minimize the energy for humanoid robot gait. In addition, we proposed simplification of kinematical solutions to generate controlled trajectories of humanoid robot legs in teleoperation tasks. The proposed control systems and strategies was evaluated in teleoperation experiments between Australia and Japan using humanoid robot Bonten-Maru. Additionally, we have developed a user-friendly Virtual Reality (VR user interface that is composed of ultrasonic 3D mouse system and a Head Mounted Display (HMD for working coexistence of human and humanoid robot in teleoperation tasks. The teleoperation experiments show good performance of the proposed system and control, and also verified the good performance for working coexistence of human and humanoid robot.

A CORBA-Based Control Architecture for Real-Time Teleoperation Tasks in a Developmental Humanoid Robot

Directory of Open Access Journals (Sweden)

Hanafiah Yussof

2011-06-01

Full Text Available This paper presents the development of new Humanoid Robot Control Architecture (HRCA platform based on Common Object Request Broker Architecture (CORBA in a developmental biped humanoid robot for real‐time teleoperation tasks. The objective is to make the control platform open for collaborative teleoperation research in humanoid robotics via the internet. Meanwhile, to generate optimal trajectory generation in bipedal walk, we proposed a real time generation of optimal gait by using Genetic Algorithms (GA to minimize the energy for humanoid robot gait. In addition, we proposed simplification of kinematical solutions to generate controlled trajectories of humanoid robot legs in teleoperation tasks. The proposed control systems and strategies was evaluated in teleoperation experiments between Australia and Japan using humanoid robot Bonten‐Maru. Additionally, we have developed a user‐ friendly Virtual Reality (VR user interface that is composed of ultrasonic 3D mouse system and a Head Mounted Display (HMD for working coexistence of human and humanoid robot in teleoperation tasks. The teleoperation experiments show good performance of the proposed system and control, and also verified the good performance for working coexistence of human and humanoid robot.

Operator learning effects in teleoperated rendezvous & docking

Science.gov (United States)

Wilde, M.; Harder, J.; Purschke, R.

Teleoperation of spacecraft proximity operations and docking requires delicate timing and coordination of spacecraft maneuvers. Experience has shown that human operators show large performance fluctuations in these areas, which are a major factor to be addressed in operator training. In order to allow the quantification of the impact of these human fluctuations on control system performance and the human perception of this performance, a learning curve study was conducted with teleoperated final approach and docking scenarios. Over a period of ten experiment days, three test participants were tasked with repeatedly completing a set of three training scenarios. The scenarios were designed to contain different combinations of the major elements of any final approach and docking situation, and to feature an increasing difficulty level. The individual difficulty levels for the three operators furthermore differed in the level of operator support functions available in their human-machine interfaces. Operator performance in the test scenarios were evaluated in the fields approach success and precision, docking safety, and approach efficiency by a combination of recorded maneuver data and questionnaires. The results show that operator experience and the associated learning curves increase operator performance substantially, regardless of the support system used. The paper also shows that the fluctuations in operator performance and self-perception are substantial between as well as within experiment days, and must be reckoned with in teleoperation system design and mission planning.

Manipulators in teleoperation

International Nuclear Information System (INIS)

Hamel, W.R.

1985-01-01

Teleoperated manipulators represent a mature technology which has evolved over nearly 40 years of applications experience. The wide range of manipulator concepts developed thus far reflect differing applications, priorities, and philosophies. The technology of teleoperated manipulators is in a rapid state of change (just as are industrial robotics) fueled by microelectronics and materials advances. Large strides in performance and dexterity are now practical and advantageous. Even though improved controls and sensory feedback will increase functionality, overall costs should be reduced as manipulator fabrication and assembly labor costs are reduced through improved manufacturing technology. As these advances begin to materialize, broader applications in nonnuclear areas should occur

Complete Low-Cost Implementation of a Teleoperated Control System for a Humanoid Robot

Directory of Open Access Journals (Sweden)

Rafael Barea

2013-01-01

Full Text Available Humanoid robotics is a field of a great research interest nowadays. This work implements a low-cost teleoperated system to control a humanoid robot, as a first step for further development and study of human motion and walking. A human suit is built, consisting of 8 sensors, 6 resistive linear potentiometers on the lower extremities and 2 digital accelerometers for the arms. The goal is to replicate the suit movements in a small humanoid robot. The data from the sensors is wirelessly transmitted via two ZigBee RF configurable modules installed on each device: the robot and the suit. Replicating the suit movements requires a robot stability control module to prevent falling down while executing different actions involving knees flexion. This is carried out via a feedback control system with an accelerometer placed on the robot’s back. The measurement from this sensor is filtered using Kalman. In addition, a two input fuzzy algorithm controlling five servo motors regulates the robot balance. The humanoid robot is controlled by a medium capacity processor and a low computational cost is achieved for executing the different algorithms. Both hardware and software of the system are based on open platforms. The successful experiments carried out validate the implementation of the proposed teleoperated system.

ANDROID BASED TELEOPERATION FOR THE FINCH ROBOT

Directory of Open Access Journals (Sweden)

Oliver Faust

2016-09-01

Full Text Available The act of creating a robot involves systems engineering and creative problem solutions. It is about using established components to create a system that works in the natural or at least in the human environment. The current project is no exception, we have used the Robot Operating System (ROS to create an android based teleoperator application for the Finch robot. A Raspberry Pi processing platform establishes the link between the android device and the Finch robot. The most creative task, during the system design, was to translate the commands from the teleoperator application into wheel movements of the Finch robot. The translation must take into account the physical setup of the robot, including unintended negative influences, such as drag. The command translation involved a nonlinear coordinate transformation. The ROS framework enabled us to focus on that nonstandard coordinate translation task by offering a high level of abstraction and the ability to create component functionalities independently.

Experiments in teleoperator and autonomous control of space robotic vehicles

Science.gov (United States)

Alexander, Harold L.

1991-01-01

A program of research embracing teleoperator and automatic navigational control of freely flying satellite robots is presented. Current research goals include: (1) developing visual operator interfaces for improved vehicle teleoperation; (2) determining the effects of different visual interface system designs on operator performance; and (3) achieving autonomous vision-based vehicle navigation and control. This research program combines virtual-environment teleoperation studies and neutral-buoyancy experiments using a space-robot simulator vehicle currently under development. Visual-interface design options under investigation include monoscopic versus stereoscopic displays and cameras, helmet-mounted versus panel-mounted display monitors, head-tracking versus fixed or manually steerable remote cameras, and the provision of vehicle-fixed visual cues, or markers, in the remote scene for improved sensing of vehicle position, orientation, and motion.

Modular architecture for robotics and teleoperation

Science.gov (United States)

Anderson, Robert J.

1996-12-03

Systems and methods for modularization and discretization of real-time robot, telerobot and teleoperation systems using passive, network based control laws. Modules consist of network one-ports and two-ports. Wave variables and position information are passed between modules. The behavior of each module is decomposed into uncoupled linear-time-invariant, and coupled, nonlinear memoryless elements and then are separately discretized.

Telerobotics: through-the-Internet teleoperation of the ABB IRB 2000 industrial robot

Science.gov (United States)

Alvares, Alberto J.; Caribe de Carvalho, Guilherme; Paulinyi, Luis F. d. A.; Alfaro, Sadek C. A.

1999-11-01

Robotic systems can be controlled remotely through the use of telerobotics. This work presents a through-the-internet teleoperation system for remotely operating the IRB2000 industrial robot. The IRB2000 controller allows external access through a RS232 serial communication link, which is based on a 42 function proprietary communication protocol. The proposed teleoperation system uses this communication capability by connecting it to a local area network based on TCP/IP (Transport Control Protocol/Internet Protocol). The system was implemented using a Client/Server architecture, having as server a UNIX (LINUX) platform.

Usability study of a vineyard teleoperated compost spreader.

Science.gov (United States)

Ferrari, Ester; Cavallo, Eugenio

2012-01-01

Teleoperation has been widely applied in modern industry because of a variety of advantages, such as providing replaceable surrogates for humans in dangerous or difficult working environments over long distances. In this paper, a usability evaluation study of a teleoperation system for a compost spreader robotic machine is presented. The machine has been designed for the application of compost in small and stepping parcels of hilly vineyards. Driving and working tasks can be controlled remotely by a portable piloting unit, reducing the risk for the operator in the event of machine overturning. Participants of the study were asked to perform a series of tasks and sub-tasks and to vocalize their thoughts while working with the machine. The tasks were designed to simulate typical user experience. Once all the tasks were accomplished each participant was asked to fill a questionnaire. The evaluation considered aspects such as learnability, ease of use, understandability, controllability, frustration, mental effort, distraction, clarity of presentation, perceived usefulness, temporal efficiency and machine aesthetic. Results show that usability evaluation helped detecting design deficiencies in the teleoperated compost spreader machine.

Teleoperation for learning by demonstration

DEFF Research Database (Denmark)

Kukliński, Kamil; Fischer, Kerstin; Marhenke, Ilka

2014-01-01

Learning by demonstration is a useful technique to augment a robot's behavioral inventory, and teleoperation allows lay users to demonstrate novel behaviors intuitively to the robot. In this paper, we compare two modes of teleoperation of an industrial robot, the demonstration by means of a data...... glove and by means of a control object (peg). Experiments with 16 lay users, performing assembly task on the Cranfield benchmark objects, show that the control peg leads to more success, more efficient demonstration and fewer errors....

How operator admittance affects the response of a teleoperation system to assistive forces – A model analytic study and simulation

International Nuclear Information System (INIS)

Wildenbeest, J.G.W.; Abbink, D.A.; Boessenkool, H.; Heemskerk, C.J.M.; Koning, J.F.

2013-01-01

Highlights: ► We developed a computational model of a human operator controlling a teleoperation system based on feedforward control, while performing a free-space motion. ► We studied how assistive forces affect the response of the combined system of telemanipulator and operator, when operator admittance changes due to task instruction or arm configuration. ► Inappropriate assistive forces can lead to assistive forces that are either not perceived, or deflect the combined system; assistive forces should be tailored to operator admittance. ► It is required to study, measure and quantitatively model operator behavior for teleoperated tasks in more detail. -- Abstract: Haptic shared control is a promising approach to increase the effectiveness of remote handling operations. While in haptic shared control the operator is continuously guided with assistive forces, the operator's response to forces is not fully understood. This study describes the development of a computational model of a human operator controlling a teleoperation system based on feedforward control. In a simulation, the operator's response to repulsive forces in free-space motions was modeled for two degrees of freedom, for two operator endpoint admittances (estimated by means of closed-loop identification techniques). The simulation results show that similar repulsive forces lead to substantial discrepancies in response when admittance settings mismatch; wrongly estimated operator admittances can lead to assistive forces that are either not perceived, or deflect the combined system of human operator and telemanipulator. It is concluded that assistive forces should be tailored to the arm configuration and the type of task performed. In order to utilize haptic shared control to its full potential, it is required to study, measure and quantitatively model operator behavior for teleoperated tasks in more detail

How operator admittance affects the response of a teleoperation system to assistive forces – A model analytic study and simulation

Energy Technology Data Exchange (ETDEWEB)

Wildenbeest, J.G.W., E-mail: j.g.w.wildenbeest@tudelft.nl [Department of Biomechanical Engineering, Delft University of Technology, Mekelweg 2, 2626 CD Delft (Netherlands); Heemskerk Innovative Technology B.V., Jonckerweg 12, 2201 DZ Noordwijk (Netherlands); Abbink, D.A. [Department of Biomechanical Engineering, Delft University of Technology, Mekelweg 2, 2626 CD Delft (Netherlands); Boessenkool, H. [FOM Institute DIFFER (Dutch Institute of Fundamental Energy Research), Association EUROTOM-FOM, Partner in the Trilateral Eurogio Cluster, P.O. Box 1207, 3430 BE Nieuwegein (Netherlands); Heemskerk, C.J.M.; Koning, J.F. [Heemskerk Innovative Technology B.V., Jonckerweg 12, 2201 DZ Noordwijk (Netherlands); FOM Institute DIFFER (Dutch Institute of Fundamental Energy Research), Association EUROTOM-FOM, Partner in the Trilateral Eurogio Cluster, P.O. Box 1207, 3430 BE Nieuwegein (Netherlands)

2013-10-15

Highlights: ► We developed a computational model of a human operator controlling a teleoperation system based on feedforward control, while performing a free-space motion. ► We studied how assistive forces affect the response of the combined system of telemanipulator and operator, when operator admittance changes due to task instruction or arm configuration. ► Inappropriate assistive forces can lead to assistive forces that are either not perceived, or deflect the combined system; assistive forces should be tailored to operator admittance. ► It is required to study, measure and quantitatively model operator behavior for teleoperated tasks in more detail. -- Abstract: Haptic shared control is a promising approach to increase the effectiveness of remote handling operations. While in haptic shared control the operator is continuously guided with assistive forces, the operator's response to forces is not fully understood. This study describes the development of a computational model of a human operator controlling a teleoperation system based on feedforward control. In a simulation, the operator's response to repulsive forces in free-space motions was modeled for two degrees of freedom, for two operator endpoint admittances (estimated by means of closed-loop identification techniques). The simulation results show that similar repulsive forces lead to substantial discrepancies in response when admittance settings mismatch; wrongly estimated operator admittances can lead to assistive forces that are either not perceived, or deflect the combined system of human operator and telemanipulator. It is concluded that assistive forces should be tailored to the arm configuration and the type of task performed. In order to utilize haptic shared control to its full potential, it is required to study, measure and quantitatively model operator behavior for teleoperated tasks in more detail.

Building a Relationship between Robot Characteristics and Teleoperation User Interfaces.

Science.gov (United States)

Mortimer, Michael; Horan, Ben; Seyedmahmoudian, Mehdi

2017-03-14

The Robot Operating System (ROS) provides roboticists with a standardized and distributed framework for real-time communication between robotic systems using a microkernel environment. This paper looks at how ROS metadata, Unified Robot Description Format (URDF), Semantic Robot Description Format (SRDF), and its message description language, can be used to identify key robot characteristics to inform User Interface (UI) design for the teleoperation of heterogeneous robot teams. Logical relationships between UI components and robot characteristics are defined by a set of relationship rules created using relevant and available information including developer expertise and ROS metadata. This provides a significant opportunity to move towards a rule-driven approach for generating the designs of teleoperation UIs; in particular the reduction of the number of different UI configurations required to teleoperate each individual robot within a heterogeneous robot team. This approach is based on using an underlying rule set identifying robots that can be teleoperated using the same UI configuration due to having the same or similar robot characteristics. Aside from reducing the number of different UI configurations an operator needs to be familiar with, this approach also supports consistency in UI configurations when a teleoperator is periodically switching between different robots. To achieve this aim, a Matlab toolbox is developed providing users with the ability to define rules specifying the relationship between robot characteristics and UI components. Once rules are defined, selections that best describe the characteristics of the robot type within a particular heterogeneous robot team can be made. A main advantage of this approach is that rather than specifying discrete robots comprising the team, the user can specify characteristics of the team more generally allowing the system to deal with slight variations that may occur in the future. In fact, by using the

Building a Relationship between Robot Characteristics and Teleoperation User Interfaces

Directory of Open Access Journals (Sweden)

Michael Mortimer

2017-03-01

Full Text Available The Robot Operating System (ROS provides roboticists with a standardized and distributed framework for real-time communication between robotic systems using a microkernel environment. This paper looks at how ROS metadata, Unified Robot Description Format (URDF, Semantic Robot Description Format (SRDF, and its message description language, can be used to identify key robot characteristics to inform User Interface (UI design for the teleoperation of heterogeneous robot teams. Logical relationships between UI components and robot characteristics are defined by a set of relationship rules created using relevant and available information including developer expertise and ROS metadata. This provides a significant opportunity to move towards a rule-driven approach for generating the designs of teleoperation UIs; in particular the reduction of the number of different UI configurations required to teleoperate each individual robot within a heterogeneous robot team. This approach is based on using an underlying rule set identifying robots that can be teleoperated using the same UI configuration due to having the same or similar robot characteristics. Aside from reducing the number of different UI configurations an operator needs to be familiar with, this approach also supports consistency in UI configurations when a teleoperator is periodically switching between different robots. To achieve this aim, a Matlab toolbox is developed providing users with the ability to define rules specifying the relationship between robot characteristics and UI components. Once rules are defined, selections that best describe the characteristics of the robot type within a particular heterogeneous robot team can be made. A main advantage of this approach is that rather than specifying discrete robots comprising the team, the user can specify characteristics of the team more generally allowing the system to deal with slight variations that may occur in the future. In fact, by

Teleoperation System with Hybrid Pneumatic-Piezoelectric Actuation for MRI-Guided Needle Insertion with Haptic Feedback.

Science.gov (United States)

Shang, Weijian; Su, Hao; Li, Gang; Fischer, Gregory S

2013-01-01

This paper presents a surgical master-slave tele-operation system for percutaneous interventional procedures under continuous magnetic resonance imaging (MRI) guidance. This system consists of a piezoelectrically actuated slave robot for needle placement with integrated fiber optic force sensor utilizing Fabry-Perot interferometry (FPI) sensing principle. The sensor flexure is optimized and embedded to the slave robot for measuring needle insertion force. A novel, compact opto-mechanical FPI sensor interface is integrated into an MRI robot control system. By leveraging the complementary features of pneumatic and piezoelectric actuation, a pneumatically actuated haptic master robot is also developed to render force associated with needle placement interventions to the clinician. An aluminum load cell is implemented and calibrated to close the impedance control loop of the master robot. A force-position control algorithm is developed to control the hybrid actuated system. Teleoperated needle insertion is demonstrated under live MR imaging, where the slave robot resides in the scanner bore and the user manipulates the master beside the patient outside the bore. Force and position tracking results of the master-slave robot are demonstrated to validate the tracking performance of the integrated system. It has a position tracking error of 0.318mm and sine wave force tracking error of 2.227N.

Teleoperation System with Hybrid Pneumatic-Piezoelectric Actuation for MRI-Guided Needle Insertion with Haptic Feedback

Science.gov (United States)

Shang, Weijian; Su, Hao; Li, Gang; Fischer, Gregory S.

2014-01-01

This paper presents a surgical master-slave tele-operation system for percutaneous interventional procedures under continuous magnetic resonance imaging (MRI) guidance. This system consists of a piezoelectrically actuated slave robot for needle placement with integrated fiber optic force sensor utilizing Fabry-Perot interferometry (FPI) sensing principle. The sensor flexure is optimized and embedded to the slave robot for measuring needle insertion force. A novel, compact opto-mechanical FPI sensor interface is integrated into an MRI robot control system. By leveraging the complementary features of pneumatic and piezoelectric actuation, a pneumatically actuated haptic master robot is also developed to render force associated with needle placement interventions to the clinician. An aluminum load cell is implemented and calibrated to close the impedance control loop of the master robot. A force-position control algorithm is developed to control the hybrid actuated system. Teleoperated needle insertion is demonstrated under live MR imaging, where the slave robot resides in the scanner bore and the user manipulates the master beside the patient outside the bore. Force and position tracking results of the master-slave robot are demonstrated to validate the tracking performance of the integrated system. It has a position tracking error of 0.318mm and sine wave force tracking error of 2.227N. PMID:25126446

Teleoperation System with Hybrid Pneumatic-Piezoelectric Actuation for MRI-Guided Needle Insertion with Haptic Feedback

OpenAIRE

Shang, Weijian; Su, Hao; Li, Gang; Fischer, Gregory S.

2013-01-01

This paper presents a surgical master-slave tele-operation system for percutaneous interventional procedures under continuous magnetic resonance imaging (MRI) guidance. This system consists of a piezoelectrically actuated slave robot for needle placement with integrated fiber optic force sensor utilizing Fabry-Perot interferometry (FPI) sensing principle. The sensor flexure is optimized and embedded to the slave robot for measuring needle insertion force. A novel, compact opto-mechanical FPI ...

Performance benefits of telerobotics and teleoperation - enhancements for an arm-based tank waste retrieval system

International Nuclear Information System (INIS)

Horschel, D.S.; Gibbons, P.W.; Draper, J.V.

1995-06-01

This report evaluates telerobotic and teleoperational arm-based retrieval systems that require advanced robotic controls. These systems will be deployed in waste retrieval activities in Hanford's Single Shell Tanks (SSTs). The report assumes that arm-based, retrieval systems will combine a teleoperational arm and control system enhanced by a number of advanced and telerobotic controls. The report describes many possible enhancements, spanning the full range of the control spectrum with the potential for technical maturation. The enhancements considered present a variety of choices and factors including: the enhancements to be included in the actual control system, safety, detailed task analyses, human factors, cost-benefit ratios, and availability and maturity of technology. Because the actual system will be designed by an offsite vendor, the procurement specifications must have the flexibility to allow bidders to propose a broad range of ideas, yet build in enough restrictions to filter out infeasible and undesirable approaches. At the same time they must allow selection of a technically promising proposal. Based on a preliminary analysis of the waste retrieval task, and considering factors such as operator limitations and the current state of robotics technology, the authors recommend a set of enhancements that will (1) allow the system to complete its waste retrieval mission, and (2) enable future upgrades in response to changing mission needs and technological advances

Performance benefits of telerobotics and teleoperation - enhancements for an arm-based tank waste retrieval system

Energy Technology Data Exchange (ETDEWEB)

Horschel, D.S. [Sandia National Labs., Albuquerque, NM (United States); Gibbons, P.W. [Westinghouse Hanford Co., Richland, WA (United States); Draper, J.V. [Oak Ridge National Lab., TN (United States)] [and others

1995-06-01

This report evaluates telerobotic and teleoperational arm-based retrieval systems that require advanced robotic controls. These systems will be deployed in waste retrieval activities in Hanford`s Single Shell Tanks (SSTs). The report assumes that arm-based, retrieval systems will combine a teleoperational arm and control system enhanced by a number of advanced and telerobotic controls. The report describes many possible enhancements, spanning the full range of the control spectrum with the potential for technical maturation. The enhancements considered present a variety of choices and factors including: the enhancements to be included in the actual control system, safety, detailed task analyses, human factors, cost-benefit ratios, and availability and maturity of technology. Because the actual system will be designed by an offsite vendor, the procurement specifications must have the flexibility to allow bidders to propose a broad range of ideas, yet build in enough restrictions to filter out infeasible and undesirable approaches. At the same time they must allow selection of a technically promising proposal. Based on a preliminary analysis of the waste retrieval task, and considering factors such as operator limitations and the current state of robotics technology, the authors recommend a set of enhancements that will (1) allow the system to complete its waste retrieval mission, and (2) enable future upgrades in response to changing mission needs and technological advances.

Multilateral haptics-based immersive teleoperation for improvised explosive device disposal

Science.gov (United States)

Erickson, David; Lacheray, Hervé; Daly, John

2013-05-01

Of great interest to police and military organizations is the development of effective improvised explosive device (IED) disposal (IEDD) technology to aid in activities such as mine field clearing, and bomb disposal. At the same time minimizing risk to personnel. This paper presents new results in the research and development of a next generation mobile immersive teleoperated explosive ordnance disposal system. This system incorporates elements of 3D vision, multilateral teleoperation for high transparency haptic feedback, immersive augmented reality operator control interfaces, and a realistic hardware-in-the-loop (HIL) 3D simulation environment incorporating vehicle and manipulator dynamics for both operator training and algorithm development. In the past year, new algorithms have been developed to facilitate incorporating commercial off-the-shelf (COTS) robotic hardware into the teleoperation system. In particular, a real-time numerical inverse position kinematics algorithm that can be applied to a wide range of manipulators has been implemented, an inertial measurement unit (IMU) attitude stabilization system for manipulators has been developed and experimentally validated, and a voice­operated manipulator control system has been developed and integrated into the operator control station. The integration of these components into a vehicle simulation environment with half-car vehicle dynamics has also been successfully carried out. A physical half-car plant is currently being constructed for HIL integration with the simulation environment.

Teleoperation environment based on virtual reality. Application of two-planes method for position measurement

International Nuclear Information System (INIS)

Yoshikawa, Hidekazu; Tezuka, Tetsuo; Inoue, Ryuji

1998-01-01

A teleoperation system based on virtual environment (VE) is an emergent technology for operating a robot in remote or hazardous environment. We have developed a VE-based teleoperation system for robot-arm manipulation in a simplified real world. The VE for manipulating the robot arm is constructed by measuring the 3D positions of the objects around the robot arm by motion-stereo method. The 3D position is estimated by using two-(calibration) planes method based on images captured by the CCD camera on the robot-arm, since the two-planes method does not need pin-hole-model assumption to the camera system. The precision of this 3D-measurement is evaluated through experiments and then derived is the theoretical model to the error in the measurement. This measurement system is applied to VE-based teleoperation experiment for Peg-in-hole practice by the robot arm. (author)

Integration of advanced teleoperation technologies for control of space robots

Science.gov (United States)

Stagnaro, Michael J.

1993-01-01

Teleoperated robots require one or more humans to control actuators, mechanisms, and other robot equipment given feedback from onboard sensors. To accomplish this task, the human or humans require some form of control station. Desirable features of such a control station include operation by a single human, comfort, and natural human interfaces (visual, audio, motion, tactile, etc.). These interfaces should work to maximize performance of the human/robot system by streamlining the link between human brain and robot equipment. This paper describes development of a control station testbed with the characteristics described above. Initially, this testbed will be used to control two teleoperated robots. Features of the robots include anthropomorphic mechanisms, slaving to the testbed, and delivery of sensory feedback to the testbed. The testbed will make use of technologies such as helmet mounted displays, voice recognition, and exoskeleton masters. It will allow tor integration and testing of emerging telepresence technologies along with techniques for coping with control link time delays. Systems developed from this testbed could be applied to ground control of space based robots. During man-tended operations, the Space Station Freedom may benefit from ground control of IVA or EVA robots with science or maintenance tasks. Planetary exploration may also find advanced teleoperation systems to be very useful.

Human-Centered Design and Evaluation of Haptic Cueing for Teleoperation of Multiple Mobile Robots.

Science.gov (United States)

Son, Hyoung Il; Franchi, Antonio; Chuang, Lewis L; Kim, Junsuk; Bulthoff, Heinrich H; Giordano, Paolo Robuffo

2013-04-01

In this paper, we investigate the effect of haptic cueing on a human operator's performance in the field of bilateral teleoperation of multiple mobile robots, particularly multiple unmanned aerial vehicles (UAVs). Two aspects of human performance are deemed important in this area, namely, the maneuverability of mobile robots and the perceptual sensitivity of the remote environment. We introduce metrics that allow us to address these aspects in two psychophysical studies, which are reported here. Three fundamental haptic cue types were evaluated. The Force cue conveys information on the proximity of the commanded trajectory to obstacles in the remote environment. The Velocity cue represents the mismatch between the commanded and actual velocities of the UAVs and can implicitly provide a rich amount of information regarding the actual behavior of the UAVs. Finally, the Velocity+Force cue is a linear combination of the two. Our experimental results show that, while maneuverability is best supported by the Force cue feedback, perceptual sensitivity is best served by the Velocity cue feedback. In addition, we show that large gains in the haptic feedbacks do not always guarantee an enhancement in the teleoperator's performance.

Experiments in augmented teleoperation for mobile robots: I

Science.gov (United States)

Witus, Gary; Hunt, Shawn; Ellis, R. Darrin

2007-04-01

Teleoperated mobile robots are beginning to be used for a variety of tasks that require movement in close quarters in the vicinity of moving and parked vehicles, buildings and other man-made structures, and the target object for inspection or manipulation. The robots must be close enough to deploy short-range sensors and manipulators, and must be able to maneuver without potentially damaging collisions. Teleoperation is fatiguing and stressful even without the requirement for close positioning. In cooperation with the TARDEC Robotic Mobility Laboratory (TRML), we are investigating approaches to reduce workload and improve performance through augmented teleoperation. Human-robot interfaces for teleoperation commonly provide two degrees-of-freedom (DoF) motion control with visual feedback from an on-board egocentric camera and no supplemental distance or orientation cueing. This paper reports on the results of preliminary experiments to assess the effects on man-machine task performance of several options for augmented teleoperation: (a) 3 DoF motion control (rotation and omni-directional translation) versus 2 DoF control (rotation and forward/reverse motion), (b) on-board egocentric camera versus fixed-position overwatch camera versus dual egocentric-and-overwatch cameras, and (c) presence or absence of distance and orientation visual cueing. We examined three dimensions of performance: completion time, spatial accuracy, and workspace area. We investigated effects on the expected completion time and on the variance in completion time. Spatial accuracy had three components: orientation, aimpoint, and distance. We collected performance under different task conditions: (a) three position-and-orientation tolerance or accuracy objectives, and (b) four travel distances between successive inspection points. We collected data from three subjects. We analyzed the main effects and conditional interaction effects among the teleoperation options and task conditions. We were

Safe teleoperation based on flexible intraoperative planning for robot-assisted laser microsurgery.

Science.gov (United States)

Mattos, Leonardo S; Caldwell, Darwin G

2012-01-01

This paper describes a new intraoperative planning system created to improve precision and safety in teleoperated laser microsurgeries. It addresses major safety issues related to real-time control of a surgical laser during teleoperated procedures, which are related to the reliability and robustness of the telecommunication channels. Here, a safe solution is presented, consisting in a new planning system architecture that maintains the flexibility and benefits of real-time teleoperation and keeps the surgeon in control of all surgical actions. The developed system is based on our virtual scalpel system for robot-assisted laser microsurgery, and allows the intuitive use of stylus to create surgical plans directly over live video of the surgical field. In this case, surgical plans are defined as graphic objects overlaid on the live video, which can be easily modified or replaced as needed, and which are transmitted to the main surgical system controller for subsequent safe execution. In the process of improving safety, this new planning system also resulted in improved laser aiming precision and improved capability for higher quality laser procedures, both due to the new surgical plan execution module, which allows very fast and precise laser aiming control. Experimental results presented herein show that, in addition to the safety improvements, the new planning system resulted in a 48% improvement in laser aiming precision when compared to the previous virtual scalpel system.

Multivariate stability of force-reflecting teleoperation: Structures of finite and infinite zeros

International Nuclear Information System (INIS)

Daniel, R.W.; McAree, P.R.

2000-01-01

This paper presents a stability analysis of force-position teleoperation under general end-effector contact. The analysis is based on the finite and infinite zero structure of the multivariable root-locus resulting from modulation of the environment stiffness. The starting point is an analysis of the stability of robot force control, motivated by the observation that the human-operator in a force reflection loop acts as a force servo, generating position commands in response to reflected force. Asymptotic root loci properties are used to establish passivity conditions on force feedback to give root locus interpretations of the well-known results that (1) feedback via the inverse joint Jacobian can lead to (kinematic) instability and that (2) passivity is preserved by kinematically proper force feedback through the transpose of the joint angle Jacobian. It is demonstrated that a fully constrained force-position teleoperation loop has an identical infinite zero structure to that of a slave manipulation under kinematically proper force control and that the dominant vibration modes of a force-position loop are fully described by a multivariable analogue of the single-input single-output pseudo-system investigated in a study by Daniel and McAree. Extension of the analysis to cover partial end-effector constraint provides a design tool for teleoperation control and serves to aid selection of teleoperation slate-arms. The paper concludes by giving a passivity condition for multiple-input multiple-output force-position teleoperation for stable contact against all environments

Human Machine Interfaces for Teleoperators and Virtual Environments

Science.gov (United States)

Durlach, Nathaniel I. (Compiler); Sheridan, Thomas B. (Compiler); Ellis, Stephen R. (Compiler)

1991-01-01

In Mar. 1990, a meeting organized around the general theme of teleoperation research into virtual environment display technology was conducted. This is a collection of conference-related fragments that will give a glimpse of the potential of the following fields and how they interplay: sensorimotor performance; human-machine interfaces; teleoperation; virtual environments; performance measurement and evaluation methods; and design principles and predictive models.

The development of radiation hardened tele-robot system - Development of path-planning and control technology for tele-operated redundant manipulator

Energy Technology Data Exchange (ETDEWEB)

Chang, Pyung Hun; Park, Ki Cheol; Park, Suk Ho [Korea Advanced Institute of Science and Technology, Taejon (Korea)

1999-04-01

This project focuses on the development of the control system for a teleoperated redundant manipulator, which performs many tasks dexterously, while avoiding obstacles, instead of human workers in the extreme situations like nuclear power plants. To this end, four consecutive research works have been performed. First, two new methods for global path-planning have been developed to inspect the global behavior of the redundant manipulator. Second, characteristics of optimal solutions(COS) under inequality constraints have been analyzed and, using the COS, how to greatly enhance the conventional redundancy resolution methods in terms of performance and repeatability has also been proposed. Third, an effective control method for a redundant manipulator has been developed, which incorporates all kinds of physical limits into practical inequality constraints and is computationally efficient for real-time purposes. Finally, using this control method as the controller of the slave redundant manipulator and developing a master manipulator, the inertial torque and gravitation torque of which are negligible, a force-reflected teleoperation control system has been developed. Through the teleoperation control system, human operator can accurately control the position and the force of the end-effector of the slave manipulator while feeling the interaction force between the slave and the workpiece. In addition, the slave redundant manipulator autonomously can control the impedance and can optimize a given performance measure while avoiding physical limits such as joint angle limits and obstacles. 49 refs., 43 figs., 10 tabs. (Author)

Using virtual objects to aid underground storage tank teleoperation

International Nuclear Information System (INIS)

Anderson, R.J.; Davies, B.

1994-01-01

In this paper we describe an algorithm by which obstructions and surface features in an underground storage tank can be modeled and used to generate virtual barrier function for a real-time telerobotic system, which provides an aid to the operator for both real-time obstacle avoidance and for surface tracking. The algorithm requires that the slave's tool and every object in the waste storage tank be decomposed into convex polyhedral primitives, with the waste surface modeled by triangular prisms. Intrusion distance and extraction vectors are then derived at every time step by applying Gilbert's polyhedra distance algorithm, which has been adapted for the task. This information is then used to determine the compression and location of nonlinear virtual spring-dampers whose total force is summed and applied to the manipulator/teleoperator system. Experimental results using a PUMA 560 and a simulated waste surface validate the approach, showing that it is possible to compute the algorithm and generate smooth, realistic pseudo forces for the teleoperator system using standard VME bus hardware

Teleoperation of Robonaut Using Finger Tracking

Science.gov (United States)

Champoux, Rachel G.; Luo, Victor

2012-01-01

With the advent of new finger tracking systems, the idea of a more expressive and intuitive user interface is being explored and implemented. One practical application for this new kind of interface is that of teleoperating a robot. For humanoid robots, a finger tracking interface is required due to the level of complexity in a human-like hand, where a joystick isn't accurate. Moreover, for some tasks, using one's own hands allows the user to communicate their intentions more effectively than other input. The purpose of this project was to develop a natural user interface for someone to teleoperate a robot that is elsewhere. Specifically, this was designed to control Robonaut on the international space station to do tasks too dangerous and/or too trivial for human astronauts. This interface was developed by integrating and modifying 3Gear's software, which includes a library of gestures and the ability to track hands. The end result is an interface in which the user can manipulate objects in real time in the user interface. then, the information is relayed to a simulator, the stand in for Robonaut, at a slight delay.

Operator dynamics for stability condition in haptic and teleoperation system: A survey.

Science.gov (United States)

Li, Hongbing; Zhang, Lei; Kawashima, Kenji

2018-04-01

Currently, haptic systems ignore the varying impedance of the human hand with its countless configurations and thus cannot recreate the complex haptic interactions. The literature does not reveal a comprehensive survey on the methods proposed and this study is an attempt to bridge this gap. The paper includes an extensive review of human arm impedance modeling and control deployed to address inherent stability and transparency issues in haptic interaction and teleoperation systems. Detailed classification and comparative study of various contributions in human arm modeling are presented and summarized in tables and diagrams. The main challenges in modeling human arm impedance for haptic robotic applications are identified. The possible future research directions are outlined based on the gaps identified in the survey. Copyright © 2018 John Wiley & Sons, Ltd.

Improving UGV teleoperation performance using novel visualization techniques and manual interfaces

Science.gov (United States)

Vozar, Steven; Tilbury, Dawn M.

2012-06-01

Unmanned ground vehicles (UGVs) are well-suited to a variety of tasks that are dangerous or repetitive for humans to perform. Despite recent advances, UGVs still suffer from reliability issues, and human operation failures have been identified as one root cause of UGV system failure. However, most literature relevant to UGV reliability does not address the effects of human errors or the user interface. Our previous work investigated the issue of user situational awareness and sense of presence in the robot workspace by implementing a Mixed Reality interface featuring a first-person video feed with an Augmented Reality overlay and a third-person Virtual Reality display. The interface was evaluated in a series of user tests in which users manually controlled a UGV with a manipulator arm using traditional input modalities including a computer mouse, keyboard and gamepad. In this study, we learned that users found it challenging to mentally map commands from the manual inputs to the robot arm behavior. Also, switching between control modalities seemed to add to the cognitive load during teleoperation tasks. A master-slave style manual controller can provide an intuitive one-to-one mapping from user input to robot pose, and has the potential to improve both operator situational awareness for teleoperation tasks and decrease mission completion time. This paper describes the design and implementation of a teleoperated UGV with a Mixed Reality visualization interface and a master-slave controller that is suitable for teleoperated mobile manipulation tasks.

Shared control on lunar spacecraft teleoperation rendezvous operations with large time delay

Science.gov (United States)

Ya-kun, Zhang; Hai-yang, Li; Rui-xue, Huang; Jiang-hui, Liu

2017-08-01

Teleoperation could be used in space on-orbit serving missions, such as object deorbits, spacecraft approaches, and automatic rendezvous and docking back-up systems. Teleoperation rendezvous and docking in lunar orbit may encounter bottlenecks for the inherent time delay in the communication link and the limited measurement accuracy of sensors. Moreover, human intervention is unsuitable in view of the partial communication coverage problem. To solve these problems, a shared control strategy for teleoperation rendezvous and docking is detailed. The control authority in lunar orbital maneuvers that involves two spacecraft as rendezvous and docking in the final phase was discussed in this paper. The predictive display model based on the relative dynamic equations is established to overcome the influence of the large time delay in communication link. We discuss and attempt to prove via consistent, ground-based simulations the relative merits of fully autonomous control mode (i.e., onboard computer-based), fully manual control (i.e., human-driven at the ground station) and shared control mode. The simulation experiments were conducted on the nine-degrees-of-freedom teleoperation rendezvous and docking simulation platform. Simulation results indicated that the shared control methods can overcome the influence of time delay effects. In addition, the docking success probability of shared control method was enhanced compared with automatic and manual modes.

A high capability teleoperated vehicle for hazardous applications

International Nuclear Information System (INIS)

Dudar, A.M.; Witherspoon, R.L.

1995-01-01

The Robotics Development Group at the Savannah River Site is developing a high performance teleoperated vehicle for use in radioactive and hazardous environments. The three-wheeled vehicle incorporates a highly dexterous 6 degree-of-freedom (DOF), hydraulically-powered manipulator made by Schilling Development, Inc. The teleoperator is called Little MoRT (MObile Radio-controlled Teleoperator) and is a modified version of a commercially available, battery-powered, warehouse vehicle. Little MoRT is controlled remotely by a universal robot controller either through a radio frequency link or a tethered cable. Six video cameras and a microphone provide the operator with audio-visual feedback of the vehicle and its surrounding environment. The vehicle also incorporates a hydraulic power unit consisting of a propane-driven engine for powering the Schilling manipulator. Little MoRT is capable of operating in outdoor as well as indoor environments and is well suited for decontamination and decommissioning activities such as dismantling, sorting, and surveying of radioactive waste

Immersive Virtual Reality with Applications to Tele-Operation and Training

Science.gov (United States)

2016-03-07

reviewed journals : Number of Papers published in non peer-reviewed journals : Final Report: Immersive Virtual Reality with Applications to Tele-Operation... Immersive Virtual Reality with Applications to Tele-Operation and Training The proposed project aims to develop a fundamental framework for...establishing an immersive virtual reality environment for robust and scalable human robotics interaction in a cooperative intelligent architecture at the

Assistant Personal Robot (APR: Conception and Application of a Tele-Operated Assisted Living Robot

Directory of Open Access Journals (Sweden)

Eduard Clotet

2016-04-01

Full Text Available This paper presents the technical description, mechanical design, electronic components, software implementation and possible applications of a tele-operated mobile robot designed as an assisted living tool. This robotic concept has been named Assistant Personal Robot (or APR for short and has been designed as a remotely telecontrolled robotic platform built to provide social and assistive services to elderly people and those with impaired mobility. The APR features a fast high-mobility motion system adapted for tele-operation in plain indoor areas, which incorporates a high-priority collision avoidance procedure. This paper presents the mechanical architecture, electrical fundaments and software implementation required in order to develop the main functionalities of an assistive robot. The APR uses a tablet in order to implement the basic peer-to-peer videoconference and tele-operation control combined with a tactile graphic user interface. The paper also presents the development of some applications proposed in the framework of an assisted living robot.

Kinetic scrolling-based position mapping for haptic teleoperation of unmanned aerial vehicles

NARCIS (Netherlands)

Ruesch, A.; Mersha, A.Y.; Stramigioli, Stefano; Carloni, Raffaella

In this paper, we present a haptic teleoperation control algorithm for unmanned aerial vehicles, applying a kinetic scrolling-based position mapping. The proposed algorithm overcomes the master workspace limitations and enables to teleoperate the aerial vehicle in unbounded workspace in a fast and

Passive hybrid force-position control for tele-operation based on real-time simulation of a virtual mechanism

International Nuclear Information System (INIS)

Joly, L.; Andriot, C.

1995-01-01

Hybrid force-position control aims at controlling position and force in separate directions. It is particularly useful to perform certain robotic tasks. In tele-operation context, passivity is important because it ensures stability when the system interacts with any passive environment. In this paper, we propose an original approach to hybrid force-position control of a force reflecting tele-robot system. It is based on real-time simulation of a virtual mechanism corresponding to the task. the resulting control law is passive. Experiments on a 6 degrees of freedom tele-operation system consisting in following a bent pipe under several control modes validate the approach. (authors). 12 refs., 6 figs

Advanced teleoperation in nuclear applications

International Nuclear Information System (INIS)

Hamel, W.R.; Feldman, M.J.; Martin, H.L.

1984-01-01

A new generation of integrated remote maintenance systems is being developed to meet the needs of future nuclear fuel reprocessing at the Oak Ridge National Laboratory. Development activities cover all aspects of an advanced teleoperated maintenance system with particular emphasis on a new force-reflecting servomanipulator concept. The new manipulator, called the advanced servomanipulator, is microprocessor controlled and is designed to achieve force-reflection performance near that of mechanical master/slave manipulators. The advanced servomanipulator uses a gear-drive transmission which permits modularization for remote maintainability (by other advanced servomanipulators) and increases reliability. Human factors analysis has been used to develop an improved man/machine interface concept based upon colorgraphic displays and menu-driven tough screens. Initial test and evaluation of two advanced servomanipulator slave arms and several other development components have begun. 9 references, 5 figures

NONLINEAR FORCE PROFILE USED TO INCREASE THE PERFORMANCE OF A HAPTIC USER INTERFACE FOR TELEOPERATING A ROBOTIC HAND

Energy Technology Data Exchange (ETDEWEB)

Anthony L. Crawford

2012-07-01

MODIFIED PAPER TITLE AND ABSTRACT DUE TO SLIGHTLY MODIFIED SCOPE: TITLE: Nonlinear Force Profile Used to Increase the Performance of a Haptic User Interface for Teleoperating a Robotic Hand Natural movements and force feedback are important elements in using teleoperated equipment if complex and speedy manipulation tasks are to be accomplished in hazardous environments, such as hot cells, glove boxes, decommissioning, explosives disarmament, and space. The research associated with this paper hypothesizes that a user interface and complementary radiation compatible robotic hand that integrates the human hand’s anthropometric properties, speed capability, nonlinear strength profile, reduction of active degrees of freedom during the transition from manipulation to grasping, and just noticeable difference force sensation characteristics will enhance a user’s teleoperation performance. The main contribution of this research is in that a system that concisely integrates all these factors has yet to be developed and furthermore has yet to be applied to a hazardous environment as those referenced above. In fact, the most prominent slave manipulator teleoperation technology in use today is based on a design patented in 1945 (Patent 2632574) [1]. The robotic hand/user interface systems of similar function as the one being developed in this research limit their design input requirements in the best case to only complementing the hand’s anthropometric properties, speed capability, and linearly scaled force application relationship (e.g. robotic force is a constant, 4 times that of the user). In this paper a nonlinear relationship between the force experienced between the user interface and the robotic hand was devised based on property differences of manipulation and grasping activities as they pertain to the human hand. The results show that such a relationship when subjected to a manipulation task and grasping task produces increased performance compared to the

On the Value of Estimating Human Arm Stiffness during Virtual Teleoperation with Robotic Manipulators.

Science.gov (United States)

Buzzi, Jacopo; Ferrigno, Giancarlo; Jansma, Joost M; De Momi, Elena

2017-01-01

Teleoperated robotic systems are widely spreading in multiple different fields, from hazardous environments exploration to surgery. In teleoperation, users directly manipulate a master device to achieve task execution at the slave robot side; this interaction is fundamental to guarantee both system stability and task execution performance. In this work, we propose a non-disruptive method to study the arm endpoint stiffness. We evaluate how users exploit the kinetic redundancy of the arm to achieve stability and precision during the execution of different tasks with different master devices. Four users were asked to perform two planar trajectories following virtual tasks using both a serial and a parallel link master device. Users' arm kinematics and muscular activation were acquired and combined with a user-specific musculoskeletal model to estimate the joint stiffness. Using the arm kinematic Jacobian, the arm end-point stiffness was derived. The proposed non-disruptive method is capable of estimating the arm endpoint stiffness during the execution of virtual teleoperated tasks. The obtained results are in accordance with the existing literature in human motor control and show, throughout the tested trajectory, a modulation of the arm endpoint stiffness that is affected by task characteristics and hand speed and acceleration.

On the Value of Estimating Human Arm Stiffness during Virtual Teleoperation with Robotic Manipulators

Directory of Open Access Journals (Sweden)

Jacopo Buzzi

2017-09-01

Full Text Available Teleoperated robotic systems are widely spreading in multiple different fields, from hazardous environments exploration to surgery. In teleoperation, users directly manipulate a master device to achieve task execution at the slave robot side; this interaction is fundamental to guarantee both system stability and task execution performance. In this work, we propose a non-disruptive method to study the arm endpoint stiffness. We evaluate how users exploit the kinetic redundancy of the arm to achieve stability and precision during the execution of different tasks with different master devices. Four users were asked to perform two planar trajectories following virtual tasks using both a serial and a parallel link master device. Users' arm kinematics and muscular activation were acquired and combined with a user-specific musculoskeletal model to estimate the joint stiffness. Using the arm kinematic Jacobian, the arm end-point stiffness was derived. The proposed non-disruptive method is capable of estimating the arm endpoint stiffness during the execution of virtual teleoperated tasks. The obtained results are in accordance with the existing literature in human motor control and show, throughout the tested trajectory, a modulation of the arm endpoint stiffness that is affected by task characteristics and hand speed and acceleration.

Tele-operated service robots : ROSE

NARCIS (Netherlands)

Osch, van M.P.W.J.; Bera, D.; Hee, van K.M.; Koks, Y.; Zeegers, H.

2014-01-01

Service robots are robots that are intended to perform tasks normally done by humans in an environment in which humans work as well. However, they are neither required to accomplish these tasks in the same way as humans nor need to look like a human being. A tele-operated robot is controlled from a

Reasons for singularity in robot teleoperation

DEFF Research Database (Denmark)

Marhenke, Ilka; Fischer, Kerstin; Savarimuthu, Thiusius Rajeeth

2014-01-01

In this paper, the causes for singularity of a robot arm in teleoperation for robot learning from demonstration are analyzed. Singularity is the alignment of robot joints, which prevents the configuration of the inverse kinematics. Inspired by users' own hypotheses, we investigated speed and dela...

Social Acceptance of a Teleoperated Android

DEFF Research Database (Denmark)

Ryuji, Yamazaki; Nishio, Shuichi; Ishiguro, Hiroshi

2012-01-01

We explored the potential of teleoperated android robots, which are embodied telecommunication media with humanlike appearances, and how they affect people in the real world when they are employed to express a telepresence and a sense of ‘being there’. In Denmark, our exploratory study focused on...

Immersive vision assisted remote teleoperation using head mounted displays

International Nuclear Information System (INIS)

Vakkapatla, Veerendrababu; Singh, Ashutosh Pratap; Rakesh, V.; Rajagopalan, C.; Murugan, S.; Sai Baba, M.

2016-01-01

Handling and inspection of irradiated material is inevitable in nuclear industry. Hot cells are shielded radiation containment chambers equipped with master slave manipulators that facilitates remote handling. The existing methods using viewing windows and cameras for viewing the contents of hot cell to manipulate the radioactive elements have problems such as optical distortion, limited distance teleoperation, limited field of view that lead to inefficient operation. This paper presents a method of achieving immersive teleoperation to operate the master slave manipulator in hot cells by exploiting the advanced tracking and display capabilities of head mounted display devices. (author)

Duty cycle testing and performance evaluation of the SM-229 teleoperator

International Nuclear Information System (INIS)

Stoughton, R.S.; Kuban, D.P.

1985-11-01

This paper contains the first known experimental studies and analyses of teleoperator performance for specific duty cycles. The results are presented in two distinct areas as position usage patterns, and as three-dimensional power grids. The position usage patterns are a valuable means to assess the available motion range. The power grids are a unique concept for evaluating joint performance. Final conclusions contain recommendations to upgrade the teleoperator for optimum performance. 3 refs., 16 figs

TAO-2/SPARTE, a language-enhanced computer aided teleoperation system

International Nuclear Information System (INIS)

Gravez, P.; Fournier, R.

1991-01-01

TAO-2 is a computer system designed by CEA/DTA/UR for the remote control of nuclear servicing servomanipulators. It results from several years of research which have led to the current availability of an industrial product featuring highly advanced performances. For undersea applications, a development has also been carried out with CYBERNETIX for controlling the new hydraulic arm built by this company. An integral element of TAO-2 is the SPARTE language which deals with off-line task programming and focuses on combined manual, automatic and mixed control modes. Additionally, it takes into account the on-line part of the human operator relative to adjustment, monitoring and incident recovery. Other promising features are hybrid control specification, mechanisms for the management of external events and 'learning by touching' capabilities. The present paper describes the basic principles of TAO-2. It first recalls the fundamentals of Computer Aided Teleoperation (CAT). The functional and hardware architectures which implement the TAO-2 CAT concepts are then outlined. The next parts emphasize the original characteristics of the SPARTE control and programming language. The paper ends with a brief presentation of our approach for CAT symbolic control

Experimental setup for evaluating an adaptive user interface for teleoperation control

Science.gov (United States)

Wijayasinghe, Indika B.; Peetha, Srikanth; Abubakar, Shamsudeen; Saadatzi, Mohammad Nasser; Cremer, Sven; Popa, Dan O.

2017-05-01

A vital part of human interactions with a machine is the control interface, which single-handedly could define the user satisfaction and the efficiency of performing a task. This paper elaborates the implementation of an experimental setup to study an adaptive algorithm that can help the user better tele-operate the robot. The formulation of the adaptive interface and associate learning algorithms are general enough to apply when the mapping between the user controls and the robot actuators is complex and/or ambiguous. The method uses a genetic algorithm to find the optimal parameters that produce the input-output mapping for teleoperation control. In this paper, we describe the experimental setup and associated results that was used to validate the adaptive interface to a differential drive robot from two different input devices; a joystick, and a Myo gesture control armband. Results show that after the learning phase, the interface converges to an intuitive mapping that can help even inexperienced users drive the system to a goal location.

Objective evaluation of situation awareness for dynamic decision makers in teleoperations

Science.gov (United States)

Endsley, Mica R.

1991-01-01

Situation awareness, a current mental mode of the environment, is critical to the ability of operators to perform complex and dynamic tasks. This should be particularly true for teleoperators, who are separated from the situation they need to be aware of. The design of the man-machine interface must be guided by the goal of maintaining and enhancing situation awareness. The objective of this work has been to build a foundation upon which research in the area can proceed. A model of dynamic human decision making which is inclusive of situation awareness will be presented, along with a definition of situation awareness. A method for measuring situation awareness will also be presented as a tool for evaluating design concepts. The Situation Awareness Global Assessment Technique (SAGAT) is an objective measure of situation awareness originally developed for the fighter cockpit environment. The results of SAGAT validation efforts will be presented. Implications of this research for teleoperators and other operators of dynamic systems will be discussed.

An assigned responsibility system for robotic teleoperation control.

Science.gov (United States)

Small, Nicolas; Lee, Kevin; Mann, Graham

2018-01-01

This paper proposes an architecture that explores a gap in the spectrum of existing strategies for robot control mode switching in adjustable autonomy. In situations where the environment is reasonably known and/or predictable, pre-planning these control changes could relieve robot operators of the additional task of deciding when and how to switch. Such a strategy provides a clear division of labour between the automation and the human operator(s) before the job even begins, allowing for individual responsibilities to be known ahead of time, limiting confusion and allowing rest breaks to be planned. Assigned Responsibility is a new form of adjustable autonomy-based teleoperation that allows the selective inclusion of automated control elements at key stages of a robot operation plan's execution. Progression through these stages is controlled by automatic goal accomplishment tracking. An implementation is evaluated through engineering tests and a usability study, demonstrating the viability of this approach and offering insight into its potential applications.

Space teleoperation research. American Nuclear Society Executive conference: Remote operations and robotics in the nuclear industry; remote maintenance in other hostile environments

Science.gov (United States)

Meintel, A. J., Jr.; Will, R. W.

1985-01-01

This presentation consists of four sections. The first section is a brief introduction to the NASA Space Program. The second portion summarized the results of a congressionally mandated study of automation and robotics for space station. The third portion presents a number of concepts for space teleoperator systems. The remainder of the presentation describes Langley Research Center's teleoperator/robotic research to support remote space operations.

A Novel Switching-Based Control Framework for Improved Task Performance in Teleoperation System With Asymmetric Time-Varying Delays.

Science.gov (United States)

Zhai, Di-Hua; Xia, Yuanqing

2018-02-01

This paper addresses the adaptive control for task-space teleoperation systems with constrained predefined synchronization error, where a novel switched control framework is investigated. Based on multiple Lyapunov-Krasovskii functionals method, the stability of the resulting closed-loop system is established in the sense of state-independent input-to-output stability. Compared with previous work, the developed method can simultaneously handle the unknown kinematics/dynamics, asymmetric varying time delays, and prescribed performance control in a unified framework. It is shown that the developed controller can guarantee the prescribed transient-state and steady-state synchronization performances between the master and slave robots, which is demonstrated by the simulation study.

Teleoperation of steerable flexible needles by combining kinesthetic and vibratory feedback.

Science.gov (United States)

Pacchierotti, Claudio; Abayazid, Momen; Misra, Sarthak; Prattichizzo, Domenico

2014-01-01

Needle insertion in soft-tissue is a minimally invasive surgical procedure that demands high accuracy. In this respect, robotic systems with autonomous control algorithms have been exploited as the main tool to achieve high accuracy and reliability. However, for reasons of safety and responsibility, autonomous robotic control is often not desirable. Therefore, it is necessary to focus also on techniques enabling clinicians to directly control the motion of the surgical tools. In this work, we address that challenge and present a novel teleoperated robotic system able to steer flexible needles. The proposed system tracks the position of the needle using an ultrasound imaging system and computes needle's ideal position and orientation to reach a given target. The master haptic interface then provides the clinician with mixed kinesthetic-vibratory navigation cues to guide the needle toward the computed ideal position and orientation. Twenty participants carried out an experiment of teleoperated needle insertion into a soft-tissue phantom, considering four different experimental conditions. Participants were provided with either mixed kinesthetic-vibratory feedback or mixed kinesthetic-visual feedback. Moreover, we considered two different ways of computing ideal position and orientation of the needle: with or without set-points. Vibratory feedback was found more effective than visual feedback in conveying navigation cues, with a mean targeting error of 0.72 mm when using set-points, and of 1.10 mm without set-points.

Haptics for Virtual Reality and Teleoperation

CERN Document Server

Mihelj, Matjaž

2012-01-01

This book covers all topics relevant for the design of haptic interfaces and teleoperation systems. The book provides the basic knowledge required for understanding more complex approaches and more importantly it introduces all issues that must be considered for designing efficient and safe haptic interfaces. Topics covered in this book provide insight into all relevant components of a haptic system. The reader is guided from understanding the virtual reality concept to the final goal of being able to design haptic interfaces for specific tasks such as nanomanipulation.  The introduction chapter positions the haptic interfaces within the virtual reality context. In order to design haptic interfaces that will comply with human capabilities at least basic understanding of human sensors-motor system is required. An overview of this topic is provided in the chapter related to human haptics. The book does not try to introduce the state-of-the-art haptic interface solutions because these tend to change quickly. On...

Robotic design analysis based on teleoperated manipulator data collection

International Nuclear Information System (INIS)

Stoughton, R.S.; Martin, H.L.

1985-01-01

Extensive data collection was performed on a servomanipulator system (TeleOperator Systems SM-229) to determine the motion range and mechanical power usage of the manipulator under direct human control. More than 50 hours of various manipulation operations were performed while joint positions and motor currents were recorded. Reduction of these data yielded histograms of the manipulator usage patterns revealing areas where future manipulator motion ranges and drive systems could be optimized. This report develops a graphical representation of mechanical power usage that relates torque and velocity to the total usage time. Methods of interpreting this representation are discussed and generalized for use in analyzing robotic systems. The resulting technique will allow designers to reevaluate an operating system and determine how to improve that system's design

A teleoperation training simulator with visual and kinesthetic force virtual reality

Science.gov (United States)

Kim, Won S.; Schenker, Paul

1992-01-01

A force-reflecting teleoperation training simulator with a high-fidelity real-time graphics display has been developed for operator training. A novel feature of this simulator is that it enables the operator to feel contact forces and torques through a force-reflecting controller during the execution of the simulated peg-in-hole task, providing the operator with the feel of visual and kinesthetic force virtual reality. A peg-in-hole task is used in our simulated teleoperation trainer as a generic teleoperation task. A quasi-static analysis of a two-dimensional peg-in-hole task model has been extended to a three-dimensional model analysis to compute contact forces and torques for a virtual realization of kinesthetic force feedback. The simulator allows the user to specify force reflection gains and stiffness (compliance) values of the manipulator hand for both the three translational and the three rotational axes in Cartesian space. Three viewing modes are provided for graphics display: single view, two split views, and stereoscopic view.

Evaluation of teleoperated surgical robots in an enclosed undersea environment.

Science.gov (United States)

Doarn, Charles R; Anvari, Mehran; Low, Thomas; Broderick, Timothy J

2009-05-01

The ability to support surgical care in an extreme environment is a significant issue for both military medicine and space medicine. Telemanipulation systems, those that can be remotely operated from a distant site, have been used extensively by the National Aeronautics and Space Administration (NASA) for a number of years. These systems, often called telerobots, have successfully been applied to surgical interventions. A further extension is to operate these robotic systems over data communication networks where robotic slave and master are separated by a great distance. NASA utilizes the National Oceanographic and Atmospheric Administration (NOAA) Aquarius underwater habitat as an analog environment for research and technology evaluation missions, known as NASA Extreme Environment Mission Operations (NEEMO). Three NEEMO missions have provided an opportunity to evaluate teleoperated surgical robotics by astronauts and surgeons. Three robotic systems were deployed to the habitat for evaluation during NEEMO 7, 9, and 12. These systems were linked via a telecommunications link to various sites for remote manipulation. Researchers in the habitat conducted a variety of tests to evaluate performance and applicability in extreme environments. Over three different NEEMO missions, components of the Automated Endoscopic System for Optimal Positioning (AESOP), the M7 Surgical System, and the RAVEN were deployed and evaluated. A number of factors were evaluated, including communication latency and semiautonomous functions. The M7 was modified to permit a remote surgeon the ability to insert a needle into simulated tissue with ultrasound guidance, resulting in the world's first semi-autonomous supervisory-controlled medical task. The deployment and operation of teleoperated surgical systems and semi-autonomous, supervisory-controlled tasks were successfully conducted.

Bilateral teleoperation control to improve transparency in stiff environment with time delay

Directory of Open Access Journals (Sweden)

M. Azadegan

2014-09-01

Full Text Available This paper proposes a new bilateral control scheme to ensure both transparency and robust stability under unknown constant time delay in stiff environment. Furthermore, this method guaranties suitable performance and robust stability when transition occurs between soft and stiff environments. This framework is composed of an adaptive sliding mode controller and an adaptive impedance controller, where online estimation of the environment impedance is performed, and then used as the desired impedance at the master side. Numerical simulations are provided to verify the theoretical results under different conditions, such as constant and time-varying delay, obstructed environment and transitioning between soft and stiff environment. Afterwards, comparison with a recent work is addressed.

Port-contact systems in bilateral telemanipulation

NARCIS (Netherlands)

Secchi, C; Stramigioli, Stefano; Fantuzzi, C.

2007-01-01

In this paper we develop one of the first control applications of the recently proposed port-contact framework. We show how it is possible to model and control a bilateral telemanipulation system using port-contact systems and we develop a port-contact impedance controller that allows to impose a

Teleoperation and beyond for assistive humanoid robots

NARCIS (Netherlands)

Goodrich, M.A.; Crandall, J.W.; Barakova, E.I.

2013-01-01

In this review, we explore how teleoperation could potentially be applied to the management of humanoid robots, with an emphasis on humanoid robots that are used in assistive roles, including clinical therapies. Since there are very few examples of the remote operation of a full humanoid, the review

Research issues in implementing remote presence in teleoperator control

Science.gov (United States)

Corker, K.; Mishkin, A. H.; Lyman, J.

1981-01-01

The concept of remote presence in telemanipulation is presented. A conceptual design of a prototype teleoperator system incorporating remote presence is described. The design is presented in functional terms, sensor, display, and control subsystem. An intermediate environment, in which the human operator is made to feel present, is explicated. The intermediate environment differs from the task environment due to the quantity and type of information presented to an operator and due to scaling factors protecting the operator from the hazards of the task environment. Potential benefits of remote presence systems, both for manipulation and for the study of human cognition and preception are discussed.

Dual Arm Work Platform teleoperated robotics system. Innovative technology summary report

International Nuclear Information System (INIS)

1998-12-01

The US Department of Energy (DOE) and the Federal Energy Technology Center (FETC) has developed a Large Scale Demonstration Project (LSDP) at the Chicago Pile-5 Research Reactor (CP-5) at Argonne National Laboratory-East (ANL). The objective of the LSDP is to demonstrate potentially beneficial Deactivation and Decommissioning (D and D) technologies in comparison with current baseline technologies. The Dual Arm Work Platform (DAWP) demonstration focused on the use of the DAWP to segment and dismantle the CP-5 reactor tank and surrounding bio-shield components (including the graphite block reflector, lead and boral sheeting) and performing some minor tasks best suited for the use of teleoperated robotics that were not evaluated in this demonstration. The DAWP system is not a commercially available product at this time. The CP-5 implementation was its first D and D application. The demonstration of the DAWP was to determine the areas on which improvements must be made to make this technology commercially viable. The results of the demonstration are included in this greenbook. It is the intention of the developers to incorporate lessons learned at this demonstration and current technological advancements in robotics into the next generation of the DAWP

An operator training simulator based on interactive virtual teleoperation: nuclear facilities maintenance applications

International Nuclear Information System (INIS)

Kim, Ki Ho; Kim, Seung Ho

1997-01-01

Remote manipulation in nuclear hazardous environment is very often complex and difficult to operate and requires excessively careful preparation. Remote slave manipulators for unstructured work are manually controlled by a human operator. Small errors made by the operator via the master manipulator during operation can cause the slave to be surffered from excessive forces and result in considerable damages to the slave iteself and its environment. In this paper, we present a prototype of an operator training simulator for use in nuclear facilities maintenance applications, as part of the ongoing Nuclear Robotics Development Program at Korea Atomic Energy Research Institute (KAERI). The operator training simulator provides a means by which, in virtual task simulation, the operator can try out and train for expected remote tasks that the real slave manipulator will perform in advance. The operator interacts with both the virtual slave and task environment through the real master. Virtual interaction force feedback is provided to the operator. We also describe a man-in-the loop control scheme to realize bilateral force reflection in virtual teleoperation

Analysis of human-in-the-loop tele-operated maintenance inspection tasks using VR

International Nuclear Information System (INIS)

Boessenkool, H.; Abbink, D.A.; Heemskerk, C.J.M.; Steinbuch, M.; Baar, M.R. de; Wildenbeest, J.G.W.; Ronden, D.; Koning, J.F.

2013-01-01

Highlights: ► Execution of tele-operated inspection tasks for ITER maintenance was analyzed. ► Human factors experiments using Virtual Reality showed to be a valuable approach. ► A large variation in time performance and number of collisions was found. ► Results indicate significant room for improvement for teleoperated free space tasks. ► A promising solution is haptic shared control: assist operator with guiding forces. -- Abstract: One of the challenges in future fusion plants such as ITER is the remote maintenance of the plant. Foreseen human-in-the-loop tele-operation is characterized by limited visual and haptic feedback from the environment, which results in degraded task performance and increased operator workload. For improved tele-operated task performance it is required to get insight in the expected tasks and problems during maintenance at ITER. By means of an exploratory human factor experiment, this paper analyses problems and bottlenecks during the execution of foreseen tele-operated maintenance at ITER, identifying most promising areas of improvement. The focus of this paper is on free space (sub)tasks where contact with the environment needs to be avoided. A group of 5 subjects was asked to carry-out an ITER related free space task (visual inspection), using a six degree of freedom master device connected to a simulated hot cell environment. The results show large variation in time performance between subjects and an increasing number of collisions for more difficult tasks, indicating room for improvement for free space (sub)tasks. The results will be used in future research on the haptic guidance strategies in the ITER Remote Handling framework

Analysis of human-in-the-loop tele-operated maintenance inspection tasks using VR

Energy Technology Data Exchange (ETDEWEB)

Boessenkool, H., E-mail: h.boessenkool@differ.nl [FOM Institute DIFFER (Dutch Institute for Fundamental Energy Research), Association EURATOM-FOM, Partner in the Trilateral Euregio Cluster, PO Box 1207, 3430 BE Nieuwegein (Netherlands); Eindhoven University of Technology, Department of Mechanical Engineering, Dynamics and Control Group, PO Box 513, 5600 MB Eindhoven (Netherlands); Abbink, D.A. [Delft University of Technology, Faculty of 3mE, BioMechanical Engineering Department, Mekelweg 2, 2628 CD Delft (Netherlands); Heemskerk, C.J.M. [Heemskerk Innovative Technology B.V., Jonckerweg 12, 2201 DZ Noordwijk (Netherlands); Steinbuch, M. [Eindhoven University of Technology, Department of Mechanical Engineering, Dynamics and Control Group, PO Box 513, 5600 MB Eindhoven (Netherlands); Baar, M.R. de [FOM Institute DIFFER (Dutch Institute for Fundamental Energy Research), Association EURATOM-FOM, Partner in the Trilateral Euregio Cluster, PO Box 1207, 3430 BE Nieuwegein (Netherlands); Eindhoven University of Technology, Department of Mechanical Engineering, Dynamics and Control Group, PO Box 513, 5600 MB Eindhoven (Netherlands); Wildenbeest, J.G.W. [Delft University of Technology, Faculty of 3mE, BioMechanical Engineering Department, Mekelweg 2, 2628 CD Delft (Netherlands); Heemskerk Innovative Technology B.V., Jonckerweg 12, 2201 DZ Noordwijk (Netherlands); Ronden, D. [FOM Institute DIFFER (Dutch Institute for Fundamental Energy Research), Association EURATOM-FOM, Partner in the Trilateral Euregio Cluster, PO Box 1207, 3430 BE Nieuwegein (Netherlands); Koning, J.F. [Heemskerk Innovative Technology B.V., Jonckerweg 12, 2201 DZ Noordwijk (Netherlands)

2013-10-15

Highlights: ► Execution of tele-operated inspection tasks for ITER maintenance was analyzed. ► Human factors experiments using Virtual Reality showed to be a valuable approach. ► A large variation in time performance and number of collisions was found. ► Results indicate significant room for improvement for teleoperated free space tasks. ► A promising solution is haptic shared control: assist operator with guiding forces. -- Abstract: One of the challenges in future fusion plants such as ITER is the remote maintenance of the plant. Foreseen human-in-the-loop tele-operation is characterized by limited visual and haptic feedback from the environment, which results in degraded task performance and increased operator workload. For improved tele-operated task performance it is required to get insight in the expected tasks and problems during maintenance at ITER. By means of an exploratory human factor experiment, this paper analyses problems and bottlenecks during the execution of foreseen tele-operated maintenance at ITER, identifying most promising areas of improvement. The focus of this paper is on free space (sub)tasks where contact with the environment needs to be avoided. A group of 5 subjects was asked to carry-out an ITER related free space task (visual inspection), using a six degree of freedom master device connected to a simulated hot cell environment. The results show large variation in time performance between subjects and an increasing number of collisions for more difficult tasks, indicating room for improvement for free space (sub)tasks. The results will be used in future research on the haptic guidance strategies in the ITER Remote Handling framework.

Effect of biased feedback on motor imagery learning in BCI-teleoperation system

Directory of Open Access Journals (Sweden)

Maryam eAlimardani

2014-04-01

Full Text Available Feedback design is an important issue in motor imagery BCI systems. Regardless, to date it has not been reported how feedback presentation can optimize co-adaptation between a human brain and such systems. This paper assesses the effect of realistic visual feedback on users’ BC performance and motor imagery skills. We previously developed a tele-operation system for a pair of humanlike robotic hands and showed that BCI control of such hands along with first-person perspective visual feedback of movements can arouse a sense of embodiment in the operators. In the first stage of this study, we found that the intensity of this ownership illusion was associated with feedback presentation and subjects’ performance during BCI motion control. In the second stage, we probed the effect of positive and negative feedback bias on subjects’ BCI performance and motor imagery skills. Although the subject specific classifier, which was set up at the beginning of experiment, detected no significant change in the subjects’ online performance, evaluation of brain activity patterns revealed that subjects’ self-regulation of motor imagery features improved due to a positive bias of feedback and a possible occurrence of ownership illusion. Our findings suggest that in general training protocols for BCIs, manipulation of feedback can play an important role in the optimization of subjects’ motor imagery skills.

Advanced Tele-operation

International Nuclear Information System (INIS)

Decreton, M.

1998-01-01

Maintenance, repair, and dismantling operations in nuclear facilities have to be performed remotely when high radiation doses exclude hands-on operation, but also to minimize contamination risks and occupational doses to the operators. Computer-aided and sensor-based tele-operation enhances safety, reliability, and performance by helping the operator in difficult tasks with poor remote environmental perception. The objectives of work in this domain are to increase the scientific knowledge of the studied phenomena, to improve the interpretation of data, to improve the piloting og experimental devices during irradiation, to reveal and to understand possible unexpected phenomena occurring during irradiation. This scientific report describes the achievements for 1997 in the area of radiation tolerance for of remote-sensing, optical fibres and optical fibre sensors

Control system design concepts for improving bilateral characteristics of master-slave manipulators

International Nuclear Information System (INIS)

Hewitt, J.E.; Siva, K.V.

1986-01-01

The paper concerns control system design concepts for improving bilateral characteristics of master-slave manipulators. In particular, the article concentrates on the identification of the remote manipulative process itself from studying direct manipulation with hand tools. Bilateral servo loop systems in operator controlled manipular systems are discussed, as well as Bond Graph modelling techniques. The performance of different kinds of bilateral servos are compared. (U.K.)

Robust Stability of Scaled-Four-Channel Teleoperation with Internet Time-Varying Delays

Directory of Open Access Journals (Sweden)

Emma Delgado

2016-04-01

Full Text Available We describe the application of a generic stability framework for a teleoperation system under time-varying delay conditions, as addressed in a previous work, to a scaled-four-channel (γ-4C control scheme. Described is how varying delays are dealt with by means of dynamic encapsulation, giving rise to mu-test conditions for robust stability and offering an appealing frequency technique to deal with the stability robustness of the architecture. We discuss ideal transparency problems and we adapt classical solutions so that controllers are proper, without single or double differentiators, and thus avoid the negative effects of noise. The control scheme was fine-tuned and tested for complete stability to zero of the whole state, while seeking a practical solution to the trade-off between stability and transparency in the Internet-based teleoperation. These ideas were tested on an Internet-based application with two Omni devices at remote laboratory locations via simulations and real remote experiments that achieved robust stability, while performing well in terms of position synchronization and force transparency.

Robust Stability of Scaled-Four-Channel Teleoperation with Internet Time-Varying Delays.

Science.gov (United States)

Delgado, Emma; Barreiro, Antonio; Falcón, Pablo; Díaz-Cacho, Miguel

2016-04-26

We describe the application of a generic stability framework for a teleoperation system under time-varying delay conditions, as addressed in a previous work, to a scaled-four-channel (γ-4C) control scheme. Described is how varying delays are dealt with by means of dynamic encapsulation, giving rise to mu-test conditions for robust stability and offering an appealing frequency technique to deal with the stability robustness of the architecture. We discuss ideal transparency problems and we adapt classical solutions so that controllers are proper, without single or double differentiators, and thus avoid the negative effects of noise. The control scheme was fine-tuned and tested for complete stability to zero of the whole state, while seeking a practical solution to the trade-off between stability and transparency in the Internet-based teleoperation. These ideas were tested on an Internet-based application with two Omni devices at remote laboratory locations via simulations and real remote experiments that achieved robust stability, while performing well in terms of position synchronization and force transparency.

Operator-in-the-loop simulation of a redundant manipulator under teleoperation

International Nuclear Information System (INIS)

Yae, K.H.; Lin, T.C.; Chern, S.T.

1993-01-01

For an interactive simulation of 7 degree-of-freedom redundant manipulator under teleoperation, this paper describes an iterative form of resolved-motion rate control in which the constraint Jacobian is constructed on-line in real time and used in the pseudoinverse method as the manipulator is teleoperated. The manipulator's tasks may involve trajectory following in free space and frequent contact with the environment through pick-and-put operation. The operator's command is interpreted as a series of increments in Cartesian space, and then the constraint Jacobian is developed between two successive increments by viewing the predecessor as the initial configuration and the successor as the target configuration. The pseudoinverse of the constraint Jacobian then generates necessary changes in joint variables and subsequently joint torque. The Jacobian constructed in this way enables us to treat both free motion and environmental contact in the same way. The simulator is built on a two-processor IRIS workstation, with one processor for graphics and the other for dynamics and control analysis. This simulator has a potential for training the teleoperator, developing operational scenarios through visualization of the simulation, and testing the design of operator-machine interface

Communications options for teleoperations

International Nuclear Information System (INIS)

Springthorpe, R.T.

1991-08-01

TELEMAN is a programme of research work on remote handling in hazardous or disordered nuclear environments, carried out for the European Atomic Agency Community by a number of participants, part funded by the CEC. The objective is to develop advanced tele-operated robots for users in the nuclear industry to contribute to safety and profitability. A study performed by AEA Technology in 1989 for the TELEMAN programme examined communications standards and made recommendations where possible. It was recognised that a control architecture needed to be defined before determining which communications standards are appropriate. Several developing areas were recommended for further study and the results of this study are reported here. (author)

Design considerations for teleoperation systems operating in gas-tight argon cells

Directory of Open Access Journals (Sweden)

Seungnam Yu

2017-12-01

Full Text Available In the nuclear industry, mechanical engineers spend a significant portion of their time designing equipment such as manipulators, bogies, mechanical grippers, and so on. Some customized designs can be considered as standard mechanical equipment in this area, although it is not unusual to find that an existing design cannot simply be copied from one project to another. Varied performance requirements can dictate that redesign, often quite extensive redesign, is required. However, if something similar has been done before, engineers could use that as a starting point for the new project. In this regard, this study presents several guidelines inspired by previous design knowledge for similar development cases. Moreover, this study presents more detailed suggestions such as design guidelines for an argon-based hot cell atmosphere and design experience for a large-scale practical hot cell facility. Design considerations and case studies dealt with in this study are dedicated to teleoperation manipulators that are used at a large-scale argon cell facility for pyroprocess integrated inactive demonstration (PRIDE, at the Korea Atomic Energy Research Institute. In particular, for case studies to support the suggested recommendations, a fabricated telemanipulator system for PRIDE is introduced, and several kinds of experimental results associated with it are presented.

Low-Latency Teleoperations for Human Exploration and Evolvable Mars Campaign

Science.gov (United States)

Lupisella, Mark; Wright, Michael; Arney, Dale; Gershman, Bob; Stillwagen, Fred; Bobskill, Marianne; Johnson, James; Shyface, Hilary; Larman, Kevin; Lewis, Ruthan;

Task analysis of human-in-the-loop tele-operated maintenance: What can be learned from JET?

International Nuclear Information System (INIS)

Boessenkool, H.; Thomas, J.; Heemskerk, C.J.M.; Baar, M.R. de; Steinbuch, M.; Abbink, D.A.

2014-01-01

Highlights: •Maintenance task execution at JET was analyzed to guide improvements for ITER. •A large variation in task duration was found for various operator experience levels. •Results indicate significant room for improvement for tele-operated performance. •Improvent of visual feedback and artificial guiding forces was considered promising. -- Abstract: Remote maintenance will determine the available uptime of future fusion plants such as ITER. Experience at predecessor JET showed that a human-in-the-loop tele-operated approach is crucial, although this approach entails drawbacks such as the unavoidable extensive operator training and relatively long execution times. These drawbacks are common knowledge, but little quantitative research is available to guide improvements (such as improved training methods, or active operator support systems). The aim of this paper is to identify the key areas for further improvement of tele-operated maintenance. This is achieved by a detailed task analysis based on recent maintenance at JET, using task logbooks and video data as well as interviews with experienced master–slave operators. The resulting task analysis shows the (sub)tasks that were most time-consuming and shows a large variance in time performance within operators, but also substantial differences between qualified operators with different levels of experience. The operator interviews indicate that intuitive (virtual) visual feedback and artificial (guiding) forces are promising directions for improvement. The results found in this study will be used for future research and development activities focusing on haptic guiding strategies, with the aim to further design and optimize RH maintenance systems for ITER and beyond

Wide-bandwidth bilateral control using two-stage actuator system

International Nuclear Information System (INIS)

Kokuryu, Saori; Izutsu, Masaki; Kamamichi, Norihiro; Ishikawa, Jun

2015-01-01

This paper proposes a two-stage actuator system that consists of a coarse actuator driven by a ball screw with an AC motor (the first stage) and a fine actuator driven by a voice coil motor (the second stage). The proposed two-stage actuator system is applied to make a wide-bandwidth bilateral control system without needing expensive high-performance actuators. In the proposed system, the first stage has a wide moving range with a narrow control bandwidth, and the second stage has a narrow moving range with a wide control bandwidth. By consolidating these two inexpensive actuators with different control bandwidths in a complementary manner, a wide bandwidth bilateral control system can be constructed based on a mechanical impedance control. To show the validity of the proposed method, a prototype of the two-stage actuator system has been developed and basic performance was evaluated by experiment. The experimental results showed that a light mechanical impedance with a mass of 10 g and a damping coefficient of 2.5 N/(m/s) that is an important factor to establish good transparency in bilateral control has been successfully achieved and also showed that a better force and position responses between a master and slave is achieved by using the proposed two-stage actuator system compared with a narrow bandwidth case using a single ball screw system. (author)

Teleoperated Visual Inspection and Surveillance with Unmanned Ground and Aerial Vehicles

Directory of Open Access Journals (Sweden)

Viatcheslav Tretyakov

2008-11-01

Full Text Available This paper introduces our robotic system named UGAV (Unmanned Ground-Air Vehicle consisting of two semi-autonomous robot platforms, an Unmanned Ground Vehicle (UGV and an Unmanned Aerial Vehicles (UAV. The paper focuses on three topics of the inspection with the combined UGV and UAV: (A teleoperated control by means of cell or smart phones with a new concept of automatic configuration of the smart phone based on a RKI-XML description of the vehicles control capabilities, (B the camera and vision system with the focus to real time feature extraction e.g. for the tracking of the UAV and (C the architecture and hardware of the UAV

Recent advances in remote coal mining machine sensing, guidance, and teleoperation

Energy Technology Data Exchange (ETDEWEB)

Ralston, J C; Hainsworth, D W; Reid, D C; Anderson, D L; McPhee, R J [CSIRO Exploration & Minerals, Kenmore, Qld. (Australia)

2001-10-01

Some recent applications of sensing, guidance and telerobotic technology in the coal mining industry are presented. Of special interest is the development of semi or fully autonomous systems to provide remote guidance and communications for coal mining equipment. The use of radar and inertial based sensors are considered in an attempt to solve the horizontal and lateral guidance problems associated with mining equipment automation. Also described is a novel teleoperated robot vehicle with unique communications capabilities, called the Numbat, which is used in underground mine safety and reconnaissance missions.

Neural-adaptive control of single-master-multiple-slaves teleoperation for coordinated multiple mobile manipulators with time-varying communication delays and input uncertainties.

Science.gov (United States)

Li, Zhijun; Su, Chun-Yi

2013-09-01

In this paper, adaptive neural network control is investigated for single-master-multiple-slaves teleoperation in consideration of time delays and input dead-zone uncertainties for multiple mobile manipulators carrying a common object in a cooperative manner. Firstly, concise dynamics of teleoperation systems consisting of a single master robot, multiple coordinated slave robots, and the object are developed in the task space. To handle asymmetric time-varying delays in communication channels and unknown asymmetric input dead zones, the nonlinear dynamics of the teleoperation system are transformed into two subsystems through feedback linearization: local master or slave dynamics including the unknown input dead zones and delayed dynamics for the purpose of synchronization. Then, a model reference neural network control strategy based on linear matrix inequalities (LMI) and adaptive techniques is proposed. The developed control approach ensures that the defined tracking errors converge to zero whereas the coordination internal force errors remain bounded and can be made arbitrarily small. Throughout this paper, stability analysis is performed via explicit Lyapunov techniques under specific LMI conditions. The proposed adaptive neural network control scheme is robust against motion disturbances, parametric uncertainties, time-varying delays, and input dead zones, which is validated by simulation studies.

Usability of stereoscopic view in teleoperation

Science.gov (United States)

Boonsuk, Wutthigrai

2015-03-01

Recently, there are tremendous growths in the area of 3D stereoscopic visualization. The 3D stereoscopic visualization technology has been used in a growing number of consumer products such as the 3D televisions and the 3D glasses for gaming systems. This technology refers to the idea that human brain develops depth of perception by retrieving information from the two eyes. Our brain combines the left and right images on the retinas and extracts depth information. Therefore, viewing two video images taken at slightly distance apart as shown in Figure 1 can create illusion of depth [8]. Proponents of this technology argue that the stereo view of 3D visualization increases user immersion and performance as more information is gained through the 3D vision as compare to the 2D view. However, it is still uncertain if additional information gained from the 3D stereoscopic visualization can actually improve user performance in real world situations such as in the case of teleoperation.

Bilateral control of master-slave manipulators with constant time delay.

Science.gov (United States)

Forouzantabar, A; Talebi, H A; Sedigh, A K

2012-01-01

This paper presents a novel teleoperation controller for a nonlinear master-slave robotic system with constant time delay in communication channel. The proposed controller enables the teleoperation system to compensate human and environmental disturbances, while achieving master and slave position coordination in both free motion and contact situation. The current work basically extends the passivity based architecture upon the earlier work of Lee and Spong (2006) [14] to improve position tracking and consequently transparency in the face of disturbances and environmental contacts. The proposed controller employs a PID controller in each side to overcome some limitations of a PD controller and guarantee an improved performance. Moreover, by using Fourier transform and Parseval's identity in the frequency domain, we demonstrate that this new PID controller preserves the passivity of the system. Simulation and semi-experimental results show that the PID controller tracking performance is superior to that of the PD controller tracking performance in slave/environmental contacts. Copyright © 2011 ISA. Published by Elsevier Ltd. All rights reserved.

Advanced teleoperation in nuclear applications: consolidated fuel reprocessing program

International Nuclear Information System (INIS)

Hamel, W.R.; Feldman, M.J.; Martin, H.L.

1984-01-01

A new generation of integrated remote maintenance systems is being developed to meet the needs of future nuclear fuel reprocessing at the Oak Ridge National Laboratory. Development activities cover all aspects of an advanced teleoperated maintenance system with particular emphasis on a new force-reflecting servomanipulator concept. The new manipulator, called the advanced servomanipulator, is microprocessor controlled and is designed to achieve force-reflection performance near that of mechanical master/slave manipulators. The advanced servomanipulator uses a gear-drive transmission which permits modularization for remote maintainability (by other advanced servomanipulators) and increases reliability. Human factors analysis has been used to develop an improved man/machine interface concept based upon colographic displays and menu-driven touch screens. Initial test and evaluation of two advanced servomanipulator slave arms and several other development components have begun. 9 references, 5 figures

Transparent Higher Order Sliding Mode Control for Nonlinear Master-Slave Systems without Velocity Measurement

Directory of Open Access Journals (Sweden)

Luis G. Garcia-Valdovinos

2015-04-01

Full Text Available Transparency has been a major objective in bilateral teleoperation systems, even in the absence of time delay induced by the communication channel, since a high degree of transparency would allow humans to drive the remote teleoperator as if he or she were directly interacting with the remote environment, with the remote teleoperator as a physical and sensorial extension of the operator. When fast convergence of position and force tracking errors are ensured by the control system, then complete transparency is obtained, which would ideally guarantee humans to be tightly kinaesthetically coupled. In this paper a model-free Cartesian second order sliding mode (SOSM PD control scheme for nonlinear master-slave systems is presented. The proposed scheme does not rely on velocity measurements and attains very fast convergence of position trajectories, with bounded tracking of force trajectories, rendering a high degree of transparency with lesser knowledge of the system. The degree of transparency can easily be improved by tuning a feedback gain in the force loop. A unique energy storage function is introduced; such that a similar Cartesian-based controller is implemented in the master and slave sides. The resulting properties of the Cartesian control structure allows the human operator to input directly Cartesian variables, which makes clearer the kinaesthetic coupling, thus the proposed controller becomes a suitable candidate for practical implementation. The performance of the proposed scheme is evaluated in a semi-experimental setup.

Slave-side devices for micromanipulation in a haptic teleoperation scenario

NARCIS (Netherlands)

Estevez Castillo, P.

2012-01-01

Haptic teleoperation is a promising approach for dealing with the manipulation of micro-objects, fabricated in small series or as prototypes, and in processes which are novel or uncertain. Human operators provide their ability to plan, understand and react when faced with unexpected situations

Experience in the use of teleoperated robotic equipment in the Spanish Nuclear Power Plants (S.R.T. Project)

International Nuclear Information System (INIS)

Bielza, M.; Gomez, J.; Izquierdo, J.A.; Bercedo, A.; Espallardo, J.A.; Martinez, A.; Carmena, P.; Pascual, J.L.

1998-01-01

The main objective of the Teleoperated Robotic Systems project (SRT) is the development of teleoperated robotic systems for use in the inspection, surveillance and maintenance operations in nuclear and radioactive installations. These systems make possible the reduction of the individual and collective doses of the workers that undertake these operations, as well as an increase of plant availability as it is possible to carry out specific tasks of inspection and surveillance in high radiation dose areas without to reduce the power of the installation. This project started in 1995 deciding to priorize the inspection equipment in a first phase. As a result of this work currently several semi-industrial products are available: ROBCAR, ROBICEN y ANAES. These have been installed for testing and commercial operation in Spanish nuclear installations. In this paper the experience of using these prototypes in the S.M. de Garona and Cofrentes nuclear power plants is described, as well as the improvements in the design of these systems derived from these experiences that have been incorporated to the industrial prototypes that are currently in the last phase of development. (Author)

A Classification of Human-to-Human Communication during the Use of Immersive Teleoperation Interfaces

DEFF Research Database (Denmark)

Kraus, Martin; Kibsgaard, Martin

2015-01-01

We propose a new classification of the human-to-human communication during the use of immersive teleoperation interfaces based on real-life examples. While a large body of research is concerned with communication in collaborative virtual environments (CVEs), less research focuses on cases where...... of the proposed classification to real environments can offer useful reference cases. Using this extended classification not only allows us to discuss and understand differences and similarities of various forms of communication in a more systematic way, but it also provides guidelines and reference cases...... for the design of immersive teleoperation interfaces that support human-to-human communication....

Robot technology

International Nuclear Information System (INIS)

Vertut, Jean; Coiffet, Philippe.

1985-01-01

Teleoperation is concerned with the exploration and exploitation of spaces which do not allow, because of their inaccessibility or hostility, direct access to man. This volume (Part 1) covers the advances in mastering teleoperation, using only a knowledge of mechanics. The story is one of a gradual orderly succession of creative designs over many years. Diagrams and photographs illustrate the designs. This a comprehensive coverage of the subject. Following a chapter on the background to the subject the chapters cover the classification of teleoperation systems, mechanical master-slave telemanipulators for handling radioactive materials, motorized unilateral telemanipulators with open-loop control, bilateral servo manipulators, transporters and vehicles and, finally, one on the art of teleoperation at the time of the introduction of computer science. The book has been translated from French. (U.K.)

Developments of STR project in the scope of teleoperation handling robotic for the operation in Spanish nuclear facilities

International Nuclear Information System (INIS)

Bielza, M.; Gomez Santamaria, J.; Izquierdo, J.A.; Martinez, S.; Linares, F.; Avello, A.; Gago, M.J.

1998-01-01

The main objective of the Teleoperated Robotic Systems project (SRT) is the development of teleoperated robotic systems for use in the inspection, surveillance and maintenance operations in nuclear and radioactive installations. These systems make possible the reduction of the individual and collective doses of the workers that undertake these operations, as well as an increase of plant availability as it is possible to carry out specific tasks of inspection and surveillance in high radiation dose areas without having to reduce the power of the installation. This project started in 1995, deciding to priorize the inspection equipment in a first phase. When this work were advanced, the development of the manipulation activities was carried out to being consider the nuclear installations needs. As a result of this work, the manipulation requirements were elaborated in order to prepare the beginning technical specifications to design the equipment s. These developments are based on a fixed manipulator which is located closed to the equipment that we want to repair, and an arm manipulator which moves by caterpillars, it is easier to control than others; and the navigation system which allows the robot self-locating in the complex area. In this paper the conclusions about the manipulation requirements are described, as well as the state of the manipulation prototype. (Author)

A novel approach to haptic tele-operation of aerial robot vehicles

NARCIS (Netherlands)

Stramigioli, Stefano; Mahony, Robert; Corke, Peter

2010-01-01

We present a novel, simple and effective approach for tele-operation of aerial robotic vehicles with haptic feedback. Such feedback provides the remote pilot with an intuitive feel of the robot's state and perceived local environment that will ensure simple and safe operation in cluttered 3D

Field analysis: approach to the design of teleoperator workstation

International Nuclear Information System (INIS)

Saint-Jean, T.; Lescoat, D.A.

1986-04-01

Following a brief review of theoretical scope this paper will characterize a methodology to the design of teleoperation workstations. This methodology is illustrated by an example - field analysis of a telemanipulation task in a hot cell. Practical informations are given: operating strategy different from the written procedure, team work organization, different skills. Recommendations are suggested as regards the writing of procedures, the training of personnel and the work organisation

Robot Teleoperation and Perception Assistance with a Virtual Holographic Display

Science.gov (United States)

Goddard, Charles O.

2012-01-01

Teleoperation of robots in space from Earth has historically been dfficult. Speed of light delays make direct joystick-type control infeasible, so it is desirable to command a robot in a very high-level fashion. However, in order to provide such an interface, knowledge of what objects are in the robot's environment and how they can be interacted with is required. In addition, many tasks that would be desirable to perform are highly spatial, requiring some form of six degree of freedom input. These two issues can be combined, allowing the user to assist the robot's perception by identifying the locations of objects in the scene. The zSpace system, a virtual holographic environment, provides a virtual three-dimensional space superimposed over real space and a stylus tracking position and rotation inside of it. Using this system, a possible interface for this sort of robot control is proposed.

Towards a Location-based Service for Early Mental Health Interventions in Disaster Response Using Minimalistic Tele-operated Android Robots Technology

Science.gov (United States)

Vahidi, H.; Mobasheri, A.; Alimardani, M.; Guan, Q.; Bakillah, M.

2014-04-01

Providing early mental health services during disaster is a great challenge in the disaster response phase. Lack of access to adequate mental-health professionals in the early stages of large-scale disasters dramatically influences the trend of a successful mental health aid. In this paper, a conceptual framework has been suggested for adopting cellphone-type tele-operated android robots in the early stages of disasters for providing the early mental health services for disaster survivors by developing a locationbased and participatory approach. The techniques of enabling GI-services in a Peer-to-Peer (P2P) environment were studied to overcome the limitations of current centralized services. Therefore, the aim of this research study is to add more flexibility and autonomy to GI web services (WMS, WFS, WPS, etc.) and alleviate to some degree the inherent limitations of these centralized systems. A P2P system Architecture is presented for the location-based service using minimalistic tele-operated android robots, and some key techniques of implementing this service using BestPeer were studied for developing this framework.

The status of two-arm bilateral servomanipulator system development

International Nuclear Information System (INIS)

Kawatsuma, S.; Fujita, Y.; Maeda, M.; Hayashi, S.; Sasao, N.; Kashihara, H.

1987-01-01

A bilateral servo-manipulator (BSM) has been developed to meet requirements for the new remote maintenance technologies. It will be applied to the Vitrification Plant (V.P.) of high-level liquid waste and FBR Fuel Recycle Pilot Plant (F.R.P.P.). Above mentioned new remote technologies are to perform the maintenance task of all equipments and machines which are installed in the large hot cell, and have several developing items such as BSM, rack, wall-through plug, remote connector and so on. Prototype II model of BSM has been designed and manufactured, adopting some new technologies to concentrate on operability, reliability and maintenability. This paper presents the status of two-arm bilateral servomanipulator system development

Congestion rents and FTR evaluations in mixed-pool-bilateral systems

International Nuclear Information System (INIS)

Liu, Minghai; Gross, George

2008-01-01

Evaluation of key metrics for congestion management, including the congestion rents and the financial transmission rights (FTR) payoffs, requires the efficient allocation of transmission services and the calculation of appropriate locational marginal prices (LMPs). This requirement is particularly acute when there are bilateral transactions coexisting with the centralized pool markets. We propose a new formulation for this purpose, which captures explicitly the contribution of the bilateral transactions to the social welfare. The proposed formulation effectively integrates the pool market and the bilateral transactions on a consistent basis and results in the more efficient allocation of the transmission resources than the conventional tool. We assess analytically the capabilities of the proposed formulation and solution and quantify the improvements in the evaluations over those done using the conventional approach. Such improvements are also illustrated using simulation results on a wide range of test systems including the IEEE 118-bus network. (author)

Expanding to teleoperation of a tight modular workshop for dismantling radioactive components

International Nuclear Information System (INIS)

Gasc, B.

1990-01-01

The CEA (French Nuclear Energy Commission) in connection with TECHNICATOME developed a tight modular workshop for the dismantling of AT1 plant facilities in LA HAGUE. This workshop constructed of reusable stainless steel panels assembled by bolting provides a tight and decontaminable working zone compatible with any building configuration. This being the case, the operators bearing ventilated suits may work under the best safety conditions on alpha-contaminated materials. For the purpose of expanding the working capacities of this workshop it was decided to develop special components for teleoperation from the outside as in a conventional cell. To meet this objective which is within the scope of the contract signed with the CEC, the following components were developed and constructed: - manipulator holder panel, - swivelling hatch panel, - wall equipment sealed transfer device and, - modular biological protection. The design, construction and tests of these new components led to their qualification and further incorporation in the list of components of the modular workshop liable to be used for teleoperation procedures

Acquisition of Basic Behaviors through Teleoperation using Robonaut

Science.gov (United States)

Campbell, Christina

2004-01-01

My area of research is in artificial intelligence and robotics. The major platform of this research is NASA's Robonaut. This humanoid robot is located at the Johnson Space Center. Prior to receiving this grant, I was able to spend two summers in Houston working with the Robonaut team, which is headed by Rob Ambrose. My work centered on teaching Robonaut to grasp a wrench based on data gathered as a human teleoperated the robot. I tried to make the procedure as general as possible so that many different motions could be taught using this method.

A design method of bilateral control system with uncertain dynamics of environments

International Nuclear Information System (INIS)

Yamada, Kou; Iida, Noriyuki; Kudou, Naoki

2002-01-01

In the present paper, we examine a design method for master-slave systems of bilateral control systems. In master-slave systems, human operator works to achieve tasks via the master and the salve system. The salve system contacts the environment and works the tasks. According to past studies, when the dynamics of environment is treated as uncertainties, the number of unstable poles of the slave system is required to be equivalent to that of the slave system with the dynamics of the environment. In some cases, the number of unstable poles of the slave system with the dynamics of environment is different from that of the slave system. We propose a simple design method of bilateral control systems such that the number of unstable poles of the slave system with the dynamics of environmental is different from that of the slave system without the dynamics of the environment. (author)

The development of robotic system for the nuclear power plants - A study on the manipulation of teleoperation system using redundant robot

Energy Technology Data Exchange (ETDEWEB)

Lee, Chung Oh; Cho, Hyung Seok; Jang, Pyung Hoon; Park, Ki Chul; Hyun, Jang Hwan; Kim, Joo Gon; Park, Young Joon; Hwang, Woong Tae; Jeon, Yong Soo; Lee, Joo Yeon; Ahn, Kyung Mo [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of)

1996-07-01

In this project the following 4 sub- projects have been studied for use in nuclear power plants. 1) Development of precision control method for the hydraulic and pneumatic actuators: The fuzzy gain tuner for the pneumatic servo position control system with the state feedback controller was designed= by using the professional knowledge. Through the experimental study, this control method was verified to obtain the optimal fain automatically. 2) Development of an universal master arm and force reflecting teleoperation system: An autonomous telerobot system with a vision based force reflection capability was developed. To effectly implement visual force feedback, 3 different control methods were also developed. 3) A study on the analysis and control of the redundant robot manipulator: An optimal joint-path of 8-DOF redundant KAEROT for the nozzle dam task was generated and its effectiveness and safety was verified by using graphic/animation tool. The proposed dynamic control algorithm for the redundant robot was applied to the experiment of planar 3- DOF redundant robot, showing good performance. 4) A study on the robot/user interface design: A set of final design and its console table was developed, which has metaphorical identity and user-friendly interface and a study mock-up was also developed to identify the possibility in a clear form. 33 refs., 3 tabs., 11 figs. (author)

A novel control framework for nonlinear time-delayed dual-master/single-slave teleoperation.

Science.gov (United States)

Ghorbanian, A; Rezaei, S M; Khoogar, A R; Zareinejad, M; Baghestan, K

2013-03-01

A novel trilateral control architecture for the Dual-master/Single-slave teleoperation is proposed in this paper. This framework has been used in surgical training and rehabilitation applications. In this structure, the slave motion has been controlled by weighted summation of signals transmitted by the operator referring to task control authority through the dominance factors. The nonlinear dynamics for telemanipulators are considered which were considered as disregarded issues in previous studies of this field. Bounded variable time-delay has been considered which affects the transmitted signals in the communication channels. Two types of controllers have been offered and an appropriate stability analysis for each controller has been demonstrated. The first controller includes Proportional with dissipative gains (P+d). The second one contains Proportional and Derivative with dissipative gains (PD+d). In both cases, the stability of the trilateral control framework is preserved by choosing appropriate controller's gains. It is shown that these controllers attempt to coordinate the positions of telemanipulators in the free motion condition. The stability of the Dual-master/Single-slave teleoperation has been proved by an appropriate Lyapunov like function and the stability conditions have been studied. In addition the proposed PD+d control architecture is modified for trilateral teleoperation with internet communication between telemanipulators that caused such communication complications as packet loss, data duplication and swapping. A number of experiments have been conducted with various levels of dominance factor to validate the effectiveness of the new control architecture. Copyright © 2012 ISA. Published by Elsevier Ltd. All rights reserved.

Markerless Kinect-Based Hand Tracking for Robot Teleoperation

Directory of Open Access Journals (Sweden)

Guanglong Du

2012-07-01

Full Text Available This paper presents a real-time remote robot teleoperation method using markerless Kinect-based hand tracking. Using this tracking algorithm, the positions of index finger and thumb in 3D can be estimated by processing depth images from Kinect. The hand pose is used as a model to specify the pose of a real-time remote robot's end-effector. This method provides a way to send a whole task to a remote robot instead of sending limited motion commands like gesture-based approaches and this method has been tested in pick-and-place tasks.

A rare case report of bilateral testicular masses as an initial manifestation of systemic sarcoidosis

Directory of Open Access Journals (Sweden)

Hiren Patel

2015-01-01

Full Text Available Sarcoidosis is an idiopathic, systemic disease that rarely involves the genitourinary tract. Here, we present a case of a 40-year-old male presented with bilateral scrotal swelling. The scrotal ultrasound showed multiple echogenic masses bilaterally ranging between 3 mm and 15 mm involving both testicles. Enlarged retroperitoneal lymph nodes were detected on the abdominal computed tomography (CT. Surgical exploration of the testes with a frozen section analysis of the left testicular mass was carried out, and it revealed noncaseating granulomas. CT scan of the chest revealed the classic bilateral hilar and mediastinal lymphadenopathy with reticulonodular infiltrates. The final pathological diagnosis was systemic sarcoidosis with bilateral testicular involvement. Treatment with high-dose corticosteroids resulted in complete resolution of the testicular mass and a significant decrease in the size of the hilar, mediastinal, and retroperitoneal lymphadenopathy.

Use of accident experience in developing criteria for teleoperator equipment

International Nuclear Information System (INIS)

Vallario, E.J.; Selby, J.M.

1985-10-01

The 1961 SL-1 reactor accident in Idaho and the Recuplex accident at Hanford are reviewed to identify problems common to emergency situations, lessons learned from accidents, criteria for emergency equipment, and recommendations for using robotics to solve problems during emergencies. Teleoperator equipment could be used to assess the extent of the damage and the condition of the reactor, retrieve dosimeters, evacuate and treat accident victims, clean up debris and decontaminate accident areas. 2 refs., 9 figs

Hydraulic bilateral construction robot; Yuatsushiki bilateral kensetsu robot

Energy Technology Data Exchange (ETDEWEB)

Maehata, K.; Mori, N. [Kayaba Industry Co. Ltd., Tokyo (Japan)

1999-05-15

Concerning a hydraulic bilateral construction robot, its system constitution, structures and functions of important components, and the results of some tests are explained, and the researches conducted at Gifu University are described. The construction robot in this report is a servo controlled system of a version developed from the mini-shovel now available in the market. It is equipped, in addition to an electrohydraulic servo control system, with various sensors for detecting the robot attitude, vibration, and load state, and with a camera for visualizing the surrounding landscape. It is also provided with a bilateral joy stick which is a remote control actuator capable of working sensation feedback and with a rocking unit that creates robot movements of rolling, pitching, and heaving. The construction robot discussed here, with output increased and response faster thanks to the employment of a hydraulic driving system for the aim of building a robot system superior in performance to the conventional model designed primarily for heavy duty, proves after tests to be a highly sophisticated remotely controlled robot control system. (NEDO)

Development program of two-arm bilateral servomanipulator system for nuclear fuel cycle facilities in PNC

International Nuclear Information System (INIS)

Kashihara, H.; Igarashi, M.; Maeda, M.; Nomizu, T.; Uematsu, K.

1984-01-01

PNC started the development program of a two-arm bilateral servomanipulator to improve remote maintenance in the planning of pilot plants for HLLW vitrification and FBR fuel reprocessing. In this paper, the development program of two-arm bilateral servomanipulators, signal and power transmissions, high performance viewing system, man-machine interface, and transporter system for manipulators will be presented. Also radiation tests for all components used in a hot cell are being performed to aid remote system design

Tele-operated search robot for human detection using histogram of oriented objects

Science.gov (United States)

Cruz, Febus Reidj G.; Avendaño, Glenn O.; Manlises, Cyrel O.; Avellanosa, James Jason G.; Abina, Jyacinth Camille F.; Masaquel, Albert M.; Siapno, Michael Lance O.; Chung, Wen-Yaw

2017-02-01

Disasters such as typhoons, tornadoes, and earthquakes are inevitable. Aftermaths of these disasters include the missing people. Using robots with human detection capabilities to locate the missing people, can dramatically reduce the harm and risk to those who work in such circumstances. This study aims to: design and build a tele-operated robot; implement in MATLAB an algorithm for the detection of humans; and create a database of human identification based on various positions, angles, light intensity, as well as distances from which humans will be identified. Different light intensities were made by using Photoshop to simulate smoke, dust and water drops conditions. After processing the image, the system can indicate either a human is detected or not detected. Testing with bodies covered was also conducted to test the algorithm's robustness. Based on the results, the algorithm can detect humans with full body shown. For upright and lying positions, detection can happen from 8 feet to 20 feet. For sitting position, detection can happen from 2 feet to 20 feet with slight variances in results because of different lighting conditions. The distances greater than 20 feet, no humans can be processed or false negatives can occur. For bodies covered, the algorithm can detect humans in cases made under given circumstances. On three positions, humans can be detected from 0 degrees to 180 degrees under normal, with smoke, with dust, and with water droplet conditions. This study was able to design and build a tele-operated robot with MATLAB algorithm that can detect humans with an overall precision of 88.30%, from which a database was created for human identification based on various conditions, where humans will be identified.

A Case of Synchronous Bilateral Upper Urinary System Urothelial Carcinoma

Directory of Open Access Journals (Sweden)

Ibrahim Buldu

2014-12-01

Full Text Available Synchronous bilateral upper urinary tract urothelial cancer (UTUC is a very rare form of urothelial cancer. In patients with high-risk unilateral UTUC, radical nephroureterectomy (RNU is the gold standard treatment. However, there is no consensus on the treatment for synchronous bilateral UTUC. Evaluation of the patient and the tumor is recommended. Bilateral nephron-sparing surgery (NSS was performed on a 53-year-old patient who presented with high-risk synchronous bilateral UTUC, and the outcome was reported.

Rash with DERMABOND PRINEO Skin Closure System Use in Bilateral Reduction Mammoplasty: A Case Series.

Science.gov (United States)

Knackstedt, R W; Dixon, J A; O'Neill, P J; Herrera, F A

2015-01-01

Background. Bilateral reduction mammoplasty is a common plastic surgery procedure that can be complicated by unfavorable scar formation along incision sites. Surgical adhesives can be utilized as an alternative or as an adjunct to conventional suture closures to help achieve good wound tension and provide an adequate barrier with excellent cosmesis. The recently introduced DERMABOND PRINEO Skin Closure System Skin Closure System combines the skin adhesive 2-octyl cyanoacrylate with a self-adhering polyester-based mesh. Proposed benefits of wound closure with DERMABOND PRINEO Skin Closure System, used with or without sutures, include its watertight seal, easy removal, microbial barrier, even distribution of tension, and reduction in wound closure time. Although allergic reactions to 2-octyl cyanoacrylate have been reported, few allergic reactions to DERMABOND PRINEO Skin Closure System have been noted in the literature. This case series describes three patients who experienced an allergic reaction to DERMABOND PRINEO Skin Closure System after undergoing elective bilateral reduction mammoplasties at our institution to further explore this topic. Methods. Retrospective chart review of bilateral reduction mammoplasty patients who received DERMABOND PRINEO Skin Closure System dressing at our institution was performed. Results. Three patients were identified as having a rash in reaction to DERMABOND PRINEO Skin Closure System after bilateral reduction mammoplasty. All three patients required systemic steroid treatment to resolve the rash. One patient was identified as having a prior adhesive reaction. Conclusions. DERMABOND PRINEO Skin Closure System has demonstrated its efficacy in optimizing scar healing and appearance. However, as we demonstrate these three allergic reactions to DERMABOND PRINEO Skin Closure System, caution must be utilized in its usage, namely, in patients with a prior adhesive allergy and in sites where moisture or friction may be apparent.

Rash with DERMABOND PRINEO Skin Closure System Use in Bilateral Reduction Mammoplasty: A Case Series

Directory of Open Access Journals (Sweden)

R. W. Knackstedt

2015-01-01

Full Text Available Background. Bilateral reduction mammoplasty is a common plastic surgery procedure that can be complicated by unfavorable scar formation along incision sites. Surgical adhesives can be utilized as an alternative or as an adjunct to conventional suture closures to help achieve good wound tension and provide an adequate barrier with excellent cosmesis. The recently introduced DERMABOND PRINEO Skin Closure System Skin Closure System combines the skin adhesive 2-octyl cyanoacrylate with a self-adhering polyester-based mesh. Proposed benefits of wound closure with DERMABOND PRINEO Skin Closure System, used with or without sutures, include its watertight seal, easy removal, microbial barrier, even distribution of tension, and reduction in wound closure time. Although allergic reactions to 2-octyl cyanoacrylate have been reported, few allergic reactions to DERMABOND PRINEO Skin Closure System have been noted in the literature. This case series describes three patients who experienced an allergic reaction to DERMABOND PRINEO Skin Closure System after undergoing elective bilateral reduction mammoplasties at our institution to further explore this topic. Methods. Retrospective chart review of bilateral reduction mammoplasty patients who received DERMABOND PRINEO Skin Closure System dressing at our institution was performed. Results. Three patients were identified as having a rash in reaction to DERMABOND PRINEO Skin Closure System after bilateral reduction mammoplasty. All three patients required systemic steroid treatment to resolve the rash. One patient was identified as having a prior adhesive reaction. Conclusions. DERMABOND PRINEO Skin Closure System has demonstrated its efficacy in optimizing scar healing and appearance. However, as we demonstrate these three allergic reactions to DERMABOND PRINEO Skin Closure System, caution must be utilized in its usage, namely, in patients with a prior adhesive allergy and in sites where moisture or friction may

Robust haptic large distance telemanipulation for ITER

International Nuclear Information System (INIS)

Heck, D.J.F.; Heemskerk, C.J.M.; Koning, J.F.; Abbasi, A.; Nijmeijer, H.

2013-01-01

Highlights: • ITER remote handling maintenance can be controlled safely over a large distance. • Bilateral teleoperation experiments were performed in a local network. • Wave variables make the controller robust against constant communication delays. • Master and slave position synchronization guaranteed by proportional action. -- Abstract: During shutdowns, maintenance crews are expected to work in 24/6 shifts to perform critical remote handling maintenance tasks on the ITER system. In this article, we investigate the possibility to safely perform these haptic maintenance tasks remotely from control stations located anywhere around the world. To guarantee stability in time delayed bilateral teleoperation, the symmetric position tracking controller using wave variables is selected. This algorithm guarantees robustness against communication delays, can eliminate wave reflections and provide position synchronization of the master and slave devices. Experiments have been conducted under realistic local network bandwidth, latency and jitter constraints. They show sufficient transparency even for substantial communication delays

Robust haptic large distance telemanipulation for ITER

Energy Technology Data Exchange (ETDEWEB)

Heck, D.J.F., E-mail: d.j.f.heck@tue.nl [Eindhoven University of Technology, Department of Mechanical Engineering, Eindhoven (Netherlands); Heemskerk, C.J.M.; Koning, J.F. [Heemskerk Innovative Technologies, Sassenheim (Netherlands); Abbasi, A.; Nijmeijer, H. [Eindhoven University of Technology, Department of Mechanical Engineering, Eindhoven (Netherlands)

2013-10-15

Highlights: • ITER remote handling maintenance can be controlled safely over a large distance. • Bilateral teleoperation experiments were performed in a local network. • Wave variables make the controller robust against constant communication delays. • Master and slave position synchronization guaranteed by proportional action. -- Abstract: During shutdowns, maintenance crews are expected to work in 24/6 shifts to perform critical remote handling maintenance tasks on the ITER system. In this article, we investigate the possibility to safely perform these haptic maintenance tasks remotely from control stations located anywhere around the world. To guarantee stability in time delayed bilateral teleoperation, the symmetric position tracking controller using wave variables is selected. This algorithm guarantees robustness against communication delays, can eliminate wave reflections and provide position synchronization of the master and slave devices. Experiments have been conducted under realistic local network bandwidth, latency and jitter constraints. They show sufficient transparency even for substantial communication delays.

Chorea in systemic lupus erythematosus: evidence for bilateral putaminal hypermetabolism on F-18 FDG PET

Energy Technology Data Exchange (ETDEWEB)

Seo, Wook Jang; Chung, Son Mi; Koh, Su Jin; Lee, Chang Keun; Yoo, Bin; Moon, Hee Bom [College of Medicine, Ulsan Univ., Seoul (Korea, Republic of); Kim, Jae Seung; Im, Joo Hyuk [Asan Medical Center, Seoul (Korea, Republic of)

2003-10-01

We describe a 54-year-old woman with systemic lupus erythematosus (SLE) who suddenly presented with chorea and had positive antiphospholipid antibodies. F-18 FDG PET showed abnormally increased glucose metabolism in bilateral putamen and primary motor cotex. Tc-99m ECD SPECT also showed abnormally increased regional cerebral blood flow in bilateral putamen. She was treated with corticosteroid and aspirin after which the symptoms improved. Four months later, follow up F-18 FDG PET showed improvement with resolution of hypermetabolism in bilateral putamen. This case suggests that striatal hypermetabolism is associated with chorea in SLE.

Detection of Nuclear Sources by UAV Teleoperation Using a Visuo-Haptic Augmented Reality Interface.

Science.gov (United States)

Aleotti, Jacopo; Micconi, Giorgio; Caselli, Stefano; Benassi, Giacomo; Zambelli, Nicola; Bettelli, Manuele; Zappettini, Andrea

2017-09-29

A visuo-haptic augmented reality (VHAR) interface is presented enabling an operator to teleoperate an unmanned aerial vehicle (UAV) equipped with a custom CdZnTe-based spectroscopic gamma-ray detector in outdoor environments. The task is to localize nuclear radiation sources, whose location is unknown to the user, without the close exposure of the operator. The developed detector also enables identification of the localized nuclear sources. The aim of the VHAR interface is to increase the situation awareness of the operator. The user teleoperates the UAV using a 3DOF haptic device that provides an attractive force feedback around the location of the most intense detected radiation source. Moreover, a fixed camera on the ground observes the environment where the UAV is flying. A 3D augmented reality scene is displayed on a computer screen accessible to the operator. Multiple types of graphical overlays are shown, including sensor data acquired by the nuclear radiation detector, a virtual cursor that tracks the UAV and geographical information, such as buildings. Experiments performed in a real environment are reported using an intense nuclear source.

New tools for C.A.D. of input devices for tele-operation with force feedback

International Nuclear Information System (INIS)

Gosselin, F.

2000-01-01

The performances of a tele-operation system are related to the master arm's ability to emulate the behavior of the remote environment. Ideally, it allows the operator to control the slave arm in a natural way as if that were an extension of its own body. The criteria to be checked for that are known but contradictory. It is thus necessary to make trade-offs on which there is not consensus. Existing input devices are therefore very varied thus more or less adapted to the tasks considered, which is in general checked a posteriori. In this document, we propose an original approach allowing to dimension the master arm a priori according to the use which one wishes to make. For that, we developed two tools: - the first one makes it possible to establish his specifications by taking account of the transmission of information between the operator and the slave arm. By exploiting their respective limitations, one is assured that the master arm will not limit the performances of the system, - the second one allows to design it (kinematics, size, motorization... ) according to the preceding specifications. For that, we use well-known theoretical tools which however are approached here as design tools. This leads to the definition of new concepts which do not appear in the literature. This approach is used to establish the specifications of a master arm for nuclear and offshore tele-operation then to design two input devices answering these specifications. The first has 3 degrees of freedom with force feedback. Its performances are higher than those of the best existing input devices. The second is a mock-up of a 6 degrees of freedom master arm. It uses a new parallel structure that is redundant in actuation and whose performances are remarkable. (author) [fr

Software Systems for Robotics An Applied Research Perspective

Directory of Open Access Journals (Sweden)

Greg Broten

2006-03-01

Full Text Available Over the past 20 years, Defence Research and Development Canada has developed numerous tele-operated unmanned ground vehicles (UGV, many founded on the ANCÆUS command and control system. This paper relates how long experience with tele-operated UGVs influenced DRDC's shift in focus from tele-operated to autonomous unmanned vehicles (UV, the forces that guided DRDC's development approach and DRDC's experience adapting a specific tool set, MIRO, to a UGV implementation.

The development of graphic simulation technology for tele-operated robot

International Nuclear Information System (INIS)

Kim, Chang Hoi; Kim, Seung Ho; Kim, Ki Ho; Jung, Seung Ho; Hwang, Suk Yeoung; Kim, Byung Soo; Seo, Yong Chil; Lee, Young Kwang

1998-02-01

In hostile environments like a nuclear power plant, human access is limited to the strict minimum due to the high-level of radiation. The design of tele-robotic system requires careful preparation because of the nature of its safety. Also, the human operator should have a capability of supervising the robot system and responding promptly to the unexpected events. In this study, the graphic simulation technology has been developed to construct tele-robotic system which can effectively perform the specified tasks in nuclear facilities. The developed graphic simulator utilizes the Indigo 2 workstation of Silicon Graphics as a main computer and its software is written in the OpenGL graphic library in X windows environments. The developed simulator, interfaced with the control system of the real robot through the ethernet, acts as a supervisory controller. Since clear and concise visual information on real robot posture and task environments can be processed in real time, the efficiency of tele-operation can be remarkably enhanced with this simulator. This simulator using advanced 3 dimensional graphics has many advantages of modeling complicated shapes of robot and constructing the virtual work environments similar to the real ones. With the use of this developed simulator, the operator can evaluate the performance of the tele-robot before it is put into real operation. This system can prevents the possible disaster of the robot resulting from the collision with its work environments. (author). 9 refs., 23 tabs., 13 figs

Bilateral IgG4-related ophthalmic disease: a strong indication for systemic imaging.

Science.gov (United States)

Wu, Albert; Andrew, Nicholas H; McNab, Alan A; Selva, Dinesh

2016-10-01

To investigate whether bilateral or unilateral IgG4-related ophthalmic disease (IgG4-ROD) is associated with extra-ophthalmic IgG4-related disease (IgG4-RD). Twin-centre retrospective observational case series of biopsy-confirmed IgG4-ROD. Clinical and radiology data were reviewed for laterality of IgG4-ROD and presence of extra-ophthalmic disease. The literature was reviewed for case series of IgG4-ROD. 40 IgG4-ROD cases were identified, with median follow-up of 36 months. At diagnosis of IgG4-ROD, all cases were screened for extra-ophthalmic disease with physical examination and blood testing. Systemic imaging was performed in 20 (50%) cases due to clinical suspicion of extra-ophthalmic disease. Of the 21 unilateral IgG4-ROD cases, 3 (14%) had extra-ophthalmic involvement. Of the 19 bilateral cases, 15 (79%) had extra-ophthalmic involvement. Extra-ophthalmic involvement was strongly associated with bilateral IgG4-ROD (pIgG4-ROD is strongly associated with extra-ophthalmic IgG4-RD. We recommend that imaging of the neck, chest, abdomen and pelvis be performed for all bilateral cases. Systemic imaging should also be considered in unilateral cases as a significant proportion of these patients will also have extra-ophthalmic disease. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Personality Perception of Robot Avatar Teleoperators in Solo and Dyadic Tasks

Directory of Open Access Journals (Sweden)

Paul Adam Bremner

2017-05-01

Full Text Available Humanoid robot avatars are a potential new telecommunication tool, whereby a user is remotely represented by a robot that replicates their arm, head, and possible face movements. They have been shown to have a number of benefits over more traditional media such as phones or video calls. However, using a teleoperated humanoid as a communication medium inherently changes the appearance of the operator, and appearance-based stereotypes are used in interpersonal judgments (whether consciously or unconsciously. One such judgment that plays a key role in how people interact is personality. Hence, we have been motivated to investigate if and how using a robot avatar alters the perceived personality of teleoperators. To do so, we carried out two studies where participants performed 3 communication tasks, solo in study one and dyadic in study two, and were recorded on video both with and without robot mediation. Judges recruited using online crowdsourcing services then made personality judgments of the participants in the video clips. We observed that judges were able to make internally consistent trait judgments in both communication conditions. However, judge agreement was affected by robot mediation, although which traits were affected was highly task dependent. Our most important finding was that in dyadic tasks personality trait perception was shifted to incorporate cues relating to the robot’s appearance when it was used to communicate. Our findings have important implications for telepresence robot design and personality expression in autonomous robots.

Bilateral metal stents for hilar biliary obstruction using a 6Fr delivery system: outcomes following bilateral and side-by-side stent deployment.

Science.gov (United States)

Law, Ryan; Baron, Todd H

2013-09-01

Controversy exists on optimal endoscopic management for palliation of malignant hilar obstruction, with advocates for metal "side-by-side" (SBS) and "stent-in-stent" (SIS) techniques. We sought to evaluate the technical feasibility, efficacy, and outcomes of bilateral biliary self-expanding metal stents (SEMS) for treatment of malignant hilar obstruction using a stent with a 6Fr delivery system. This was a single-center, retrospective review of all patients who underwent bilateral placement of Zilver® biliary SEMS for malignant hilar obstruction from January 2010 to August 2012. Patients underwent endoscopic retrograde cholangiopancreatography with placement of stents using either the SIS or SBS stent techniques. Twenty-four patients (19 men, mean age 63 years) underwent bilateral stenting for malignant hilar obstruction during the study period. Seventeen and seven patients underwent the SBS and SIS technique, respectively. Cholangiocarcinoma (n=14) was the most common cause of hilar obstruction. Initial technical success was achieved in 24/24 (100%) of patients; however, 12 (50%) patients required re-intervention during the study period (median 98 days). Comparison of the SBS and SIS groups revealed no statistical difference with respect to need for re-intervention (P=0.31), successful re-intervention (P=0.60), or procedural length (P=0.89). Use of bilateral Zilver® SEMS in either the SBS or SIS configuration is safe, technically feasible, and effective for drainage of malignant hilar obstruction; however, duration of stent patency and procedure-free survival remain variable.

A tele-operated mobile ultrasound scanner using a light-weight robot.

Science.gov (United States)

Delgorge, Cécile; Courrèges, Fabien; Al Bassit, Lama; Novales, Cyril; Rosenberger, Christophe; Smith-Guerin, Natalie; Brù, Concepció; Gilabert, Rosa; Vannoni, Maurizio; Poisson, Gérard; Vieyres, Pierre

2005-03-01

This paper presents a new tele-operated robotic chain for real-time ultrasound image acquisition and medical diagnosis. This system has been developed in the frame of the Mobile Tele-Echography Using an Ultralight Robot European Project. A light-weight six degrees-of-freedom serial robot, with a remote center of motion, has been specially designed for this application. It holds and moves a real probe on a distant patient according to the expert gesture and permits an image acquisition using a standard ultrasound device. The combination of mechanical structure choice for the robot and dedicated control law, particularly nearby the singular configuration allows a good path following and a robotized gesture accuracy. The choice of compression techniques for image transmission enables a compromise between flow and quality. These combined approaches, for robotics and image processing, enable the medical specialist to better control the remote ultrasound probe holder system and to receive stable and good quality ultrasound images to make a diagnosis via any type of communication link from terrestrial to satellite. Clinical tests have been performed since April 2003. They used both satellite or Integrated Services Digital Network lines with a theoretical bandwidth of 384 Kb/s. They showed the tele-echography system helped to identify 66% of lesions and 83% of symptomatic pathologies.

Architectural study of the design and operation of advanced force feedback manual controllers

Science.gov (United States)

Tesar, Delbert; Kim, Whee-Kuk

1990-01-01

A teleoperator system consists of a manual controller, control hardware/software, and a remote manipulator. It was employed in either hazardous or unstructured, and/or remote environments. In teleoperation, the main-in-the-loop is the central concept that brings human intelligence to the teleoperator system. When teleoperation involves contact with an uncertain environment, providing the feeling of telepresence to the human operator is one of desired characteristics of the teleoperator system. Unfortunately, most available manual controllers in bilateral or force-reflecting teleoperator systems can be characterized by their bulky size, high costs, or lack of smoothness and transparency, and elementary architectures. To investigate other alternatives, a force-reflecting, 3 degree of freedom (dof) spherical manual controller is designed, analyzed, and implemented as a test bed demonstration in this research effort. To achieve an improved level of design to meet criteria such as compactness, portability, and a somewhat enhanced force-reflecting capability, the demonstration manual controller employs high gear-ratio reducers. To reduce the effects of the inertia and friction on the system, various force control strategies are applied and their performance investigated. The spherical manual controller uses a parallel geometry to minimize inertial and gravitational effects on its primary task of transparent information transfer. As an alternative to the spherical 3-dof manual controller, a new conceptual (or parallel) spherical 3-dof module is introduced with a full kinematic analysis. Also, the resulting kinematic properties are compared to those of other typical spherical 3-dof systems. The conceptual design of a parallel 6-dof manual controller and its kinematic analysis is presented. This 6-dof manual controller is similar to the Stewart Platform with the actuators located on the base to minimize the dynamic effects. Finally, a combination of the new 3-dof and 6-dof

Bilateral cochlear implantation in a patient with bilateral temporal bone fractures.

Science.gov (United States)

Chung, Jae Ho; Shin, Myung Chul; Min, Hyun Jung; Park, Chul Won; Lee, Seung Hwan

2011-01-01

With the emphasis on bilateral hearing nowadays, bilateral cochlear implantation has been tried out for bilateral aural rehabilitation. Bilateral sensorineural hearing loss caused by head trauma can get help from cochlear implantation. We present the case of a 44-year-old man with bilateral otic capsule violating temporal bone fractures due to head trauma. The patient demonstrated much improved audiometric and psychoacoustic performance after bilateral cochlear implantation. We believe bilateral cochlear implantation in such patient can be a very effective tool for rehabilitation. Copyright © 2011 Elsevier Inc. All rights reserved.

Detection of Nuclear Sources by UAV Teleoperation Using a Visuo-Haptic Augmented Reality Interface

Directory of Open Access Journals (Sweden)

Jacopo Aleotti

2017-09-01

Full Text Available A visuo-haptic augmented reality (VHAR interface is presented enabling an operator to teleoperate an unmanned aerial vehicle (UAV equipped with a custom CdZnTe-based spectroscopic gamma-ray detector in outdoor environments. The task is to localize nuclear radiation sources, whose location is unknown to the user, without the close exposure of the operator. The developed detector also enables identification of the localized nuclear sources. The aim of the VHAR interface is to increase the situation awareness of the operator. The user teleoperates the UAV using a 3DOF haptic device that provides an attractive force feedback around the location of the most intense detected radiation source. Moreover, a fixed camera on the ground observes the environment where the UAV is flying. A 3D augmented reality scene is displayed on a computer screen accessible to the operator. Multiple types of graphical overlays are shown, including sensor data acquired by the nuclear radiation detector, a virtual cursor that tracks the UAV and geographical information, such as buildings. Experiments performed in a real environment are reported using an intense nuclear source.

Mechatronic systems and materials III

CERN Document Server

Gosiewski, Zdzislaw

2009-01-01

This very interesting volume is divided into 24 sections; each of which covers, in detail, one aspect of the subject-matter: I. Industrial robots; II. Microrobotics; III. Mobile robots; IV. Teleoperation, telerobotics, teleoperated semi-autonomous systems; V. Sensors and actuators in mechatronics; VI. Control of mechatronic systems; VII. Analysis of vibration and deformation; VIII. Optimization, optimal design; IX. Integrated diagnostics; X. Failure analysis; XI. Tribology in mechatronic systems; XII. Analysis of signals; XIII. Measurement techniques; XIV. Multifunctional and smart materials;

A Surgical Robot Teleoperation Framework for Providing Haptic Feedback Incorporating Virtual Envrioment-Based Guidance

Directory of Open Access Journals (Sweden)

Adnan Munawar

2016-08-01

Full Text Available In robot-assisted tele-operated laparoscopic surgeries, the patient side manipulators are controlled via the master manipulators that are controlled by the surgeon. The current generation of robots approved for laparoscopic surgery lack haptic feedback. In theory, haptic feedback would enhance the surgical procedures by enabling better coordination between the hand movements that are improved by the tactile sense of the operating environment. This research presents an overall control framework for a haptic feedback on existing robot platforms, and demonstrated on the daVinci Research Kit (dVRK system. The paper discusses the implementation of a flexible framework that incorporates a stiffness control with gravity compensation for the surgeons manipulator and a sensing and collision detection algorithm for calculating the interaction between the patients manipulators and the surgical area.

Low-cost teleoperator-controlled vehicle for damage assessment and radiation dose measurement

International Nuclear Information System (INIS)

Tyree, W.H.

1991-01-01

A low-cost, disposable, radio-controlled, remote-reading, ionizing radiation and surveillance teleoperator re-entry vehicle has been built. The vehicle carries equipment, measures radiation levels, and evaluates building conditions. The basic vehicle, radio control with amplifiers, telemetry, elevator, and video camera with monitor cost less than $2500. Velcro-mounted alpha, beta-gamma, and neutron sensing equipment is used in the present system. Many types of health physics radiation measuring equipment may be substituted on the vehicle. The system includes a black-and-white video camera to observe the environment surrounding the vehicle. The camera is mounted on a vertical elevator extendible to 11 feet above the floor. The present vehicle uses a video camera with an umbilical cord between the vehicle and the operators. Preferred operation would eliminate the umbilical. Video monitoring equipment is part of the operator control system. Power for the vehicle equipment is carried on board and supplied by sealed lead-acid batteries. Radios are powered by 9-V alkaline batteries. The radio control receiver, servo drivers, high-power amplifier and 49-MHz FM transceivers were irradiated at moderate rates with neutron and gamma doses to 3000 Rem and 300 Rem, respectively, to ensure system operation

Kinematics and Dynamics of Motion Control Based on Acceleration Control

Science.gov (United States)

Ohishi, Kiyoshi; Ohba, Yuzuru; Katsura, Seiichiro

The first IEEE International Workshop on Advanced Motion Control was held in 1990 pointed out the importance of physical interpretation of motion control. The software servoing technology is now common in machine tools, robotics, and mechatronics. It has been intensively developed for the numerical control (NC) machines. Recently, motion control in unknown environment will be more and more important. Conventional motion control is not always suitable due to the lack of adaptive capability to the environment. A more sophisticated ability in motion control is necessary for compliant contact with environment. Acceleration control is the key technology of motion control in unknown environment. The acceleration control can make a motion system to be a zero control stiffness system without losing the robustness. Furthermore, a realization of multi-degree-of-freedom motion is necessary for future human assistance. A human assistant motion will require various control stiffness corresponding to the task. The review paper focuses on the modal coordinate system to integrate the various control stiffness in the virtual axes. A bilateral teleoperation is a good candidate to consider the future human assistant motion and integration of decentralized systems. Thus the paper reviews and discusses the bilateral teleoperation from the control stiffness and the modal control design points of view.

Bilateral breast carcinoma: results with breast conservation therapy and a comparison with bilateral mastectomy

International Nuclear Information System (INIS)

Kim, David H.; Haffty, Bruce G.

1996-01-01

between the BCT, UCT, and BMAST groups with respect to age, histology, clinical stage, primary tumor size, axillary nodal status, or adjuvant systemic therapy. As noted below, there were no statistically significant differences between the three study groups with respect to overall survival, disease-free survival, distant metastasis-free survival, or local regional relapse-free survival. It is noteworthy that there was no significant difference between the local breast relapse rate and the chest wall relapse rate when comparing the conservatively treated group and the bilateral mastectomy group. Conclusions: Patients with bilateral breast carcinoma presenting either synchronously or metachronously are suitable candidates for bilateral conservative treatment. Outcome of these patients with respect to all measurable endpoints did not significantly differ from patients treated conservatively for unilateral breast cancer, or for their counterparts with bilateral disease of similar stage treated with bilateral mastectomy. Of particular note, the 10-year local regional relapse-free rate of patients undergoing bilateral mastectomy did not differ significantly from the local regional relapse rate of those patients treated with bilateral conservative treatment

The Effect of Trial-by-trial Adaptation on Conflicts in Haptic Shared Control for Free-Air Teleoperation Tasks

NARCIS (Netherlands)

de Jonge, A. W.; Wildenbeest, J. G. W.; Boessenkool, H.; Abbink, D. A.

2016-01-01

Haptic shared control can improve execution of teleoperation and driving tasks. However, shared control designs may suffer from conflicts between individual human operators and constant haptic assistance when their desired trajectories differ, leading to momentarily increased forces, discomfort or

Development and demonstration of a teleoperated modular open-quotes snakeclose quotes robot system. Final report, September 30, 1986--December 31, 1993

International Nuclear Information System (INIS)

Tesar, D.; Hooper, R.

1995-01-01

The U.S. Department of Energy has provided support to four universities and the Oak Ridge National Laboratory in order to pursue research leading to the development and deployment of advanced robotic systems capable of performing tasks that generate significant occupational radiation exposure and/or whose execution times can be reduced if performed by an automated system. The goal was to develop advanced robotic systems capable of performing surveillance, maintenance, and repair tasks in nuclear facilities and other hazardous environments. The approach to achieving the program objective was a transition from teleoperation to the capability of autonomous operation within three successive generations of robotic systems. The robotic system will always have the capability to request human assistance. The development of general purpose robots to perform skilled labor tasks in restricted environments was shown to have extensive payback in areas of energy systems (nuclear and fossil units), chemical plants, fire fighting, space operations, underwater activities, defense, and other hazardous activities. The strategy that was used to achieve the program goals in an efficient and timely manner consisted in utilizing, and advancing where required, state-of-the-art robotics technology through close interaction between the universities and the manufacturers and operators of nuclear power plants. The research effort showed that a broad range of applications for the robotic systems existed for the improved operation of nuclear reactors and in other hazardous tasks. As a consequence, each institution was able to obtain additional support from other agencies, e.g., DoD and NASA. Areas of cooperation with other nations (e.g., Japan, France, Germany) were utilized

Expert operator preferences in remote manipulator control systems

International Nuclear Information System (INIS)

Sundstrom, E.; Draper, J.V.; Fausz, A.; Woods, H.

1995-06-01

This report describes a survey of expert remote manipulator operators designed to identify features of control systems related to operator efficiency and comfort. It provides information for designing the control center for the Single-Shell Tank Waste Retrieval Manipulator System (TWRMS) Test Bed, described in a separate report. Research questions concerned preferred modes of control, optimum work sessions, sources of operator fatigue, importance of control system design features, and desired changes in control rooms. Participants comprised four expert remote manipulator operators at Oak Ridge National Laboratory, who individually have from 9 to 20 years of experience using teleoperators. The operators had all used rate and position control, and all preferred bilateral (force-reflecting) position control. They reported spending an average of 2.75 h in control of a teleoperator system during a typical shift. All were accustomed to working in a crew of two and alternating control and support roles in 2-h rotations in an 8-h shift. Operators reported that fatigue in using remote manipulator systems came mainly from watching TV monitors and making repetitive motions. Three of four experienced symptoms, including headaches and sore eyes, wrists, and back. Of 17 features of control rooms rated on importance, highest ratings went to comfort and support provided by the operator chair, location of controls, location of video monitors, video image clarity, types of controls, and control modes. When asked what they wanted to change, operators said work stations designed for comfort; simpler, lighter hand-controls; separate controls for each camera; better placement of remote camera; color monitors; and control room layouts that support crew interaction. Results of this small survey reinforced the importance of ergonomic factors in remote manipulation

Bilateral Non-arteritic Anterior Ischaemic Optic Neuropathy as the Presentation of Systemic Amyloidosis.

Science.gov (United States)

Kanaan, M Z; Lorenzi, A R; Thampy, N; Pandit, R; Dayan, Margaret

2017-12-01

A 75-year-old hypertensive female with stable idiopathic intermediate uveitis presented with bilateral sequential optic neuropathy with optic disc swelling. The optic neuropathy in the first affected eye (right) was thought to be due to non-arteritic anterior ischaemic optic neuropathy (NAION). Asymptomatic left optic disc swelling was found at routine review 2 months later, and a diagnosis of giant cell arteritis (GCA) was sought. Temporal artery duplex ultrasound showed the "halo sign," but a subsequent temporal artery biopsy showed light-chain (AL) amyloidosis with no signs of giant cell arteritis. In this case, bilateral sequential ischaemic optic neuropathy mimicking non-arteritic anterior ischaemic optic neuropathy was the presenting sign of systemic amyloidosis involving the temporal arteries.

Infectious mononucleosis presenting as bilateral acute dacryocystitis.

Science.gov (United States)

Atkinson, P L; Ansons, A M; Patterson, A

1990-01-01

A case of infectious mononucleosis presenting as bilateral acute dacryocystitis in a 7-year-old girl is reported. Acute dacryocystitis is uncommon in this age group, and an underlying systemic illness should be suspected particularly when it is bilateral. Images PMID:2275940

The inspection of a radiologically contaminated pipeline using a teleoperated pipe crawler

International Nuclear Information System (INIS)

Fogle, R.F.; Kuelske, K.; Kellner, R.A.

1995-01-01

In the 1950s, the Savannah River Site built an open, unlined retention basin to temporarily store potentially radionuclide contaminated cooling water from a chemical separations process and storm water drainage from a nearby waste management facility that stored large quantities of nuclear fission byproducts in carbon steel tanks. The retention basin was retired from service in 1972 when a new, lined basin was completed. In 1978, the old retention basin was excavated, backfilled with uncontaminated dirt, and covered with grass. At the same time, much of the underground process pipeline leading to the basin was abandoned. Since the closure of the retention basin, new environmental regulations require that the basin undergo further assessment to determine whether additional remediation is required. A visual and radiological inspection of the pipeline was necessary to aid in the remediation decision making process for the retention basin system. A teleoperated pipe crawler inspection system was developed to survey the abandoned sections of underground pipelines leading to the retired retention basin. This paper will describe the background to this project, the scope of the investigation, the equipment requirements, and the results of the pipeline inspection

A Modular Telerobot Control System for Accident Response

International Nuclear Information System (INIS)

Anderson, Robert J.; Shirey, David L.

1999-01-01

The Accident Response Mobile Manipulator System (ARMMS) is a teleoperated emergency response vehicle that deploys two hydraulic manipulators, five cameras, and an array of sensors to the scene of an incident. It is operated from a remote base station that can be situated up to four kilometers away from the site. Recently, a modular telerobot control architecture called SMART (Sandia's Modular Architecture for Robotic and Teleoperation) was applied to ARMMS to improve the precision, safety, and operability of the manipulators on board. Using SMART, a prototype manipulator control system was developed in a couple of days, and an integrated working system was demonstrated within a couple of months. New capabilities such as camera teleoperation, autonomous tool changeout and dual manipulator control have been incorporated. The final system incorporates twenty-two separate modules and implements eight different behavior modes. This paper describes the integration of SMART into the ARMMS system

Supervised Remote Robot with Guided Autonomy and Teleoperation (SURROGATE): A Framework for Whole-Body Manipulation

Science.gov (United States)

Hebert, Paul; Ma, Jeremy; Borders, James; Aydemir, Alper; Bajracharya, Max; Hudson, Nicolas; Shankar, Krishna; Karumanchi, Sisir; Douillard, Bertrand; Burdick, Joel

2015-01-01

The use of the cognitive capabilties of humans to help guide the autonomy of robotics platforms in what is typically called "supervised-autonomy" is becoming more commonplace in robotics research. The work discussed in this paper presents an approach to a human-in-the-loop mode of robot operation that integrates high level human cognition and commanding with the intelligence and processing power of autonomous systems. Our framework for a "Supervised Remote Robot with Guided Autonomy and Teleoperation" (SURROGATE) is demonstrated on a robotic platform consisting of a pan-tilt perception head, two 7-DOF arms connected by a single 7-DOF torso, mounted on a tracked-wheel base. We present an architecture that allows high-level supervisory commands and intents to be specified by a user that are then interpreted by the robotic system to perform whole body manipulation tasks autonomously. We use a concept of "behaviors" to chain together sequences of "actions" for the robot to perform which is then executed real time.

Development and demonstration of a teleoperated modular {open_quotes}snake{close_quotes} robot system. Final report, September 30, 1986--December 31, 1993

Energy Technology Data Exchange (ETDEWEB)

Tesar, D.; Hooper, R.

1995-04-12

The U.S. Department of Energy has provided support to four universities and the Oak Ridge National Laboratory in order to pursue research leading to the development and deployment of advanced robotic systems capable of performing tasks that generate significant occupational radiation exposure and/or whose execution times can be reduced if performed by an automated system. The goal was to develop advanced robotic systems capable of performing surveillance, maintenance, and repair tasks in nuclear facilities and other hazardous environments. The approach to achieving the program objective was a transition from teleoperation to the capability of autonomous operation within three successive generations of robotic systems. The robotic system will always have the capability to request human assistance. The development of general purpose robots to perform skilled labor tasks in restricted environments was shown to have extensive payback in areas of energy systems (nuclear and fossil units), chemical plants, fire fighting, space operations, underwater activities, defense, and other hazardous activities. The strategy that was used to achieve the program goals in an efficient and timely manner consisted in utilizing, and advancing where required, state-of-the-art robotics technology through close interaction between the universities and the manufacturers and operators of nuclear power plants. The research effort showed that a broad range of applications for the robotic systems existed for the improved operation of nuclear reactors and in other hazardous tasks. As a consequence, each institution was able to obtain additional support from other agencies, e.g., DoD and NASA. Areas of cooperation with other nations (e.g., Japan, France, Germany) were utilized.

Stabilizing impacts in force-reflecting teleoperation using distance-to-impact estimates

International Nuclear Information System (INIS)

McAree, P.R.; Daniel, R.W.

2000-01-01

The level of force that can be stably reflected to the human operator in a force-reflecting teleoperator is constrained by the dynamics of impact between the slave arm and its environment. This paper models the underlying dynamics of impact and describes how the impact effects can be minimized using estimates of the distance between the slave and objects in its workspace. The approach is based on stochastic variational principles and seeks to limit the momentum of the slave arm at impact. Preliminary experimental results show that the approach allows extension of the range of frequencies that can be stably reflected to the human operator

Simultaneous bilateral patellar tendon rupture ?

OpenAIRE

Moura, Diogo Lino; Marques, Jos? Pedro; Lucas, Francisco Manuel; Fonseca, Fernando Pereira

2016-01-01

Bilateral patellar tendon rupture is a rare entity, often associated with systemic diseases and patellar tendinopathy. The authors report a rare case of a 34-year-old man with simultaneous bilateral rupture of the patellar tendon caused by minor trauma. The patient is a retired basketball player with no past complaints of chronic knee pain and a history of steroid use. Surgical management consisted in primary end-to-end tendon repair protected temporarily with cerclage wiring, followed by a s...

Detection of Nuclear Sources by UAV Teleoperation Using a Visuo-Haptic Augmented Reality Interface

OpenAIRE

Jacopo Aleotti; Giorgio Micconi; Stefano Caselli; Giacomo Benassi; Nicola Zambelli; Manuele Bettelli; Andrea Zappettini

2017-01-01

A visuo-haptic augmented reality (VHAR) interface is presented enabling an operator to teleoperate an unmanned aerial vehicle (UAV) equipped with a custom CdZnTe-based spectroscopic gamma-ray detector in outdoor environments. The task is to localize nuclear radiation sources, whose location is unknown to the user, without the close exposure of the operator. The developed detector also enables identification of the localized nuclear sources. The aim of the VHAR interface is to increase the sit...

A Rare Entity: Bilateral First Rib Fractures Accompanying Bilateral Scapular Fractures

OpenAIRE

Gulbahar, Gultekin; Kaplan, Tevfik; Turker, Hasan Bozkurt; Gundogdu, Ahmet Gokhan; Han, Serdar

2015-01-01

First rib fractures are scarce due to their well-protected anatomic locations. Bilateral first rib fractures accompanying bilateral scapular fractures are very rare, although they may be together with scapular and clavicular fractures. According to our knowledge, no case of bilateral first rib fractures accompanying bilateral scapular fractures has been reported, so we herein discussed the diagnosis, treatment, and complications of bone fractures due to thoracic trauma in bias of this rare en...

A Rare Entity: Bilateral First Rib Fractures Accompanying Bilateral Scapular Fractures.

Science.gov (United States)

Gulbahar, Gultekin; Kaplan, Tevfik; Turker, Hasan Bozkurt; Gundogdu, Ahmet Gokhan; Han, Serdar

2015-01-01

First rib fractures are scarce due to their well-protected anatomic locations. Bilateral first rib fractures accompanying bilateral scapular fractures are very rare, although they may be together with scapular and clavicular fractures. According to our knowledge, no case of bilateral first rib fractures accompanying bilateral scapular fractures has been reported, so we herein discussed the diagnosis, treatment, and complications of bone fractures due to thoracic trauma in bias of this rare entity.

A Discrete-Time Algorithm for Stiffness Extraction from sEMG and Its Application in Antidisturbance Teleoperation

Directory of Open Access Journals (Sweden)

Peidong Liang

2016-01-01

Full Text Available We have developed a new discrete-time algorithm of stiffness extraction from muscle surface electromyography (sEMG collected from human operator’s arms and have applied it for antidisturbance control in robot teleoperation. The variation of arm stiffness is estimated from sEMG signals and transferred to a telerobot under variable impedance control to imitate human motor control behaviours, particularly for disturbance attenuation. In comparison to the estimation of stiffness from sEMG, the proposed algorithm is able to reduce the nonlinear residual error effect and to enhance robustness and to simplify stiffness calibration. In order to extract a smoothing stiffness enveloping from sEMG signals, two enveloping methods are employed in this paper, namely, fast linear enveloping based on low pass filtering and moving average and amplitude monocomponent and frequency modulating (AM-FM method. Both methods have been incorporated into the proposed stiffness variance estimation algorithm and are extensively tested. The test results show that stiffness variation extraction based on the two methods is sensitive and robust to attenuation disturbance. It could potentially be applied for teleoperation in the presence of hazardous surroundings or human robot physical cooperation scenarios.

THE EUROPEAN UNION’S BILATERAL APPROACH

Directory of Open Access Journals (Sweden)

Ludmila BORTA

2014-12-01

Full Text Available The EU is a world economic power and a major trading partner for most countries. All the time, this region has been interested and has acted towards a free and fair trade. The decrease and even the elimination of tariff and non-tariff barriers in the world trade are among the main objectives of the EU strategy for international trade. At the moment, the elusive outcome of the WTO Doha Round has led to the proliferation of bilateral trade agreements worldwide. Although the EU remains committed to further development of the multilateral trading system, however, the EU still has appealed also to the development of bilateral trade relations. The aim of this paper is to illustrate the current bilateral dimension of the common commercial policy of the EU. In conclusion, to describe this bilateral approach of the EU we are using one word, namely “diversity”.

[Bilateral cochlear implants].

Science.gov (United States)

Müller, J

2017-07-01

Cochlear implants (CI) are standard for the hearing rehabilitation of severe to profound deafness. Nowadays, if bilaterally indicated, bilateral implantation is usually recommended (in accordance with German guidelines). Bilateral implantation enables better speech discrimination in quiet and in noise, and restores directional and spatial hearing. Children with bilateral CI are able to undergo hearing-based hearing and speech development. Within the scope of their individual possibilities, bilaterally implanted children develop faster than children with unilateral CI and attain, e.g., a larger vocabulary within a certain time interval. Only bilateral implantation allows "binaural hearing," with all the benefits that people with normal hearing profit from, namely: better speech discrimination in quiet and in noise, as well as directional and spatial hearing. Naturally, the developments take time. Binaural CI users benefit from the same effects as normal hearing persons: head shadow effect, squelch effect, and summation and redundancy effects. Sequential CI fitting is not necessarily disadvantageous-both simultaneously and sequentially fitted patients benefit in a similar way. For children, earliest possible fitting and shortest possible interval between the two surgeries seems to positively influence the outcome if bilateral CI are indicated.

Performance experiments with alternative advanced teleoperator control modes for a simulated solar maximum satellite repair

Science.gov (United States)

Das, H.; Zak, H.; Kim, W. S.; Bejczy, A. K.; Schenker, P. S.

1992-01-01

Experiments are described which were conducted at the JPL Advanced Teleoperator Lab to demonstrate and evaluate the effectiveness of various teleoperator control modes in the performance of a simulated Solar Max Satellite Repair (SMSR) task. THe SMSR was selected as a test because it is very rich in performance capability requirements and it actually has been performed by two EVA astronauts in the Space Shuttle Bay in 1984. The main subtasks are: thermal blanket removal; installation of a hinge attachment for electrical panel opening; opening of electrical panel; removal of electrical connectors; relining of cable bundles; replacement of electrical panel; securing parts and cables; re-mate electrical connectors; closing of electrical panel; and reinstating thermal blanket. The current performance experiments are limited to thermal blanket cutting, electrical panel unbolting and handling electrical bundles and connectors. In one formal experiment even different control modes were applied to the unbolting and reinsertion of electrical panel screws subtasks. The seven control modes are alternative combinations of manual position and rate control with force feedback and remote compliance referenced to force-torque sensor information. Force-torque sensor and end effector position data and task completion times were recorded for analysis and quantification of operator performance.

Multilateral and bilateral agreements

International Nuclear Information System (INIS)

Koponen, H.

1993-01-01

Finland has made both multilateral and bilateral agreements on the exchange of information related to radiation safety. The first arrangements for international agreements and exchange of information were made after the Chernobyl accident. In 1987, Finland joined the convention on early notification of a nuclear power accident coordinated by International Atomic Energy Agency. The convention is applied to accidents that cause of may cause emissions of radioactive substances that might affect the radiation safety of another country. Besides the convention on early notification, some other individual agreements have also been made. These include the International Nuclear Event Scale (INES) system and power companies own information exchange systems. Finland has conducted bilateral agreements with the Nordic countries and the Soviet Union on the notification of accidents and exchange of nuclear power plant information. Today, Russia answers for the Soviet Union's contractual obligations. (orig.)

A Rare Entity: Bilateral First Rib Fractures Accompanying Bilateral Scapular Fractures

Directory of Open Access Journals (Sweden)

Gultekin Gulbahar

2015-01-01

Full Text Available First rib fractures are scarce due to their well-protected anatomic locations. Bilateral first rib fractures accompanying bilateral scapular fractures are very rare, although they may be together with scapular and clavicular fractures. According to our knowledge, no case of bilateral first rib fractures accompanying bilateral scapular fractures has been reported, so we herein discussed the diagnosis, treatment, and complications of bone fractures due to thoracic trauma in bias of this rare entity.

Bilateral cochlear implantation: current concepts, indications, and results.

Science.gov (United States)

Basura, Gregory J; Eapen, Rose; Buchman, Craig A

2009-12-01

The optimal treatment for bilateral hearing loss continues to evolve as cochlear implant (CI) and hearing aid technologies advance, as does our understanding of the central auditory system. Ongoing discussions continue on the validity and feasibility of bilateral CI in terms of performance, justification of need, medical/surgical safety concerns, and economics. The purpose of this review article is to provide an update on the advantages and disadvantages of bilateral CI and to provide a discussion on timing (simultaneous vs. sequential), technology (bimodal vs. binaural) and feasibility. Binaural advantages are found in both adult and pediatric bilateral CI recipients, the greatest being the head shadow effect and improvements in localization and loudness summation. This theoretically offers an advantage over their unilateral implanted counterparts in terms of improved sound localization and enhanced speech perception under noisy conditions. Most investigators agree that bilateral stimulation during critical periods of development is paramount for optimizing auditory functioning in children. Currently, bilateral CI is widely accepted as a safe and effective means of bilateral auditory stimulation.

Generalized approach to bilateral control for EMG driven exoskeleton

Directory of Open Access Journals (Sweden)

Gradetsky Valery

2017-01-01

Full Text Available The paper discusses a generalized approach to bilateral control for EMG driven exoskeleton systems. In this paper we consider a semi-automatic mechatronic system that is controlled via human muscle activity (EMG level. The problem is to understand how the movement of the exoskeleton effects on the control. The considered system can be described in terms of bilateral control. This means the existence of force feedback from the object via the exoskeleton links and drives to operator. The simulation of the considered model was held on the MATLAB Simulink. The mathematical model of the bilateral system with exoskeleton and operator was developed. Transient functions for different dynamic parameters were obtained. It was shown that force feedback is essential for the R&D of such systems.

Risk undermined in the bilateral pharmaceutical regulatory system in Taiwan.

Science.gov (United States)

Wang, Hui-Po; Wang, Chun-Li

2018-04-01

The concept of Pharmacovigilance Planning and Risk Minimization Planning (PVP/RMP), initiated by the International Conference on Harmonization (ICH), addressed an important conceptual change from monitoring the safety of individual medicine to proactively conducting risk prevention for the minimization of medication error. However, the implementation of PVP/RMP is a challenge in societies like Taiwan where irrational medication and co-medication is prevalent. It is even more difficult in Taiwan where two regulatory bodies are governing pharmaceutical affairs, namely Taiwan Food and Drug Administration (TFDA) in charge of Western Medicine (WM) and the Department of Chinese Medicine and Pharmacy (DCMP) in charge of Traditional Chinese Medicine (TCM). There are thus dual-tract drug approval panels, two GMP controls and two independent adverse drug event reporting systems. This rendered irrational co-medication of WM and TCM undetectable and the standard tools for monitoring pharmacovigilance inapplicable. The bilateral regulatory system is conceptually unscientific in accordance with PVP/RMP and unethical from humanity point of view. The first part of this review delivers (1) social aspects of polypharmacy in Taiwan; (2) regulatory aspects of pharmaceutical administration; (3) risks undermined in the bilateral regulatory system and (4) pharmacoepidemiology in relation to the risk of polypharmacy. As evidence-based medicine (EBM) forms the fundamental risk-benefit assessment on medication, the second part of this review delivers (1) the scientific aspects of the beauty and the odds of biological system that governs host-xenobiotics interaction; (2) conceptual evolution from product management (pharmacovigilance) to risk management (PVP/RMP); (3) non-biased due process is essential for risk-benefit assessment on medicinal products and (4) the opinion of the authors on system building for safe medication. Copyright © 2018. Published by Elsevier B.V.

Tele-Operated Echography and Remote Guidance for Performing Tele-Echography on Geographically Isolated Patients

Directory of Open Access Journals (Sweden)

Philippe Arbeille

2016-06-01

Full Text Available Objective: To evaluate the performance of three tele-echography systems for routine use in isolated medical centers. Methods: Three systems were used for deep (abdomen, pelvis, fetal and superficial (muscle, thyroid, carotid artery examinations: (a a robotic arm (RA holding an echographic probe; (b an echograph with a motorized probe (MP; and (c remote guidance (RG where the patient site operator performed the examination assisted by an expert via videoconference. All systems were tested in the same medical center located 60 km away from the university hospital. Results: A total of 340 remote echography examinations were performed (41% RA and MP, 59% RG. MP and RA allowed full control of the probe orientation by the expert, and provided diagnoses in 97% of cases. The use of RG was sufficient for superficial vessel examinations and provided diagnoses in 98% of cases but was not suited for deep or superficial organs. Assessment of superficial organs was best accomplished using the MP. Discussion: Both teleoperated systems provided control of the probe orientation by the expert necessary for obtaining appropriate views of deep organs but the MP was much more ergonomic and easier to use than the RA. RG was appropriate for superficial vessels while the MP was better for superficial volumic organs.

Usability testing of a mobile robotic system for in-home telerehabilitation.

Science.gov (United States)

Boissy, Patrick; Brière, Simon; Corriveau, Hélène; Grant, Andrew; Lauria, Michel; Michaud, François

2011-01-01

Mobile robots designed to enhance telepresence in the support of telehealth services are being considered for numerous applications. TELEROBOT is a teleoperated mobile robotic platform equipped with videoconferencingcapabilities and designed to be used in a home environment to. In this study, learnability of the system's teleoperation interface and controls was evaluated with ten rehabilitation professionals during four training sessions in a laboratory environment and in an unknown home environment while performing the execution of a standardized evaluation protocol typically used in home care. Results show that the novice teleoperators' performances on two of the four metrics used (number of command and total time) improved significantly across training sessions (ANOVAS, phome environment during navigation tasks (r=0,77 and 0,60). With only 4 hours of training, rehabilitation professionals were able learn to teleoperate successfully TELEROBOT. However teleoperation performances remained significantly less efficient then those of an expert. Under the home task condition (navigating the home environment from one point to the other as fast as possible) this translated to completion time between 350 seconds (best performance) and 850 seconds (worse performance). Improvements in other usability aspects of the system will be needed to meet the requirements of in-home telerehabilitation.

A longitudinal study of the bilateral benefit in children with bilateral cochlear implants.

Science.gov (United States)

Asp, Filip; Mäki-Torkko, Elina; Karltorp, Eva; Harder, Henrik; Hergils, Leif; Eskilsson, Gunnar; Stenfelt, Stefan

2015-02-01

To study the development of the bilateral benefit in children using bilateral cochlear implants by measurements of speech recognition and sound localization. Bilateral and unilateral speech recognition in quiet, in multi-source noise, and horizontal sound localization was measured at three occasions during a two-year period, without controlling for age or implant experience. Longitudinal and cross-sectional analyses were performed. Results were compared to cross-sectional data from children with normal hearing. Seventy-eight children aged 5.1-11.9 years, with a mean bilateral cochlear implant experience of 3.3 years and a mean age of 7.8 years, at inclusion in the study. Thirty children with normal hearing aged 4.8-9.0 years provided normative data. For children with cochlear implants, bilateral and unilateral speech recognition in quiet was comparable whereas a bilateral benefit for speech recognition in noise and sound localization was found at all three test occasions. Absolute performance was lower than in children with normal hearing. Early bilateral implantation facilitated sound localization. A bilateral benefit for speech recognition in noise and sound localization continues to exist over time for children with bilateral cochlear implants, but no relative improvement is found after three years of bilateral cochlear implant experience.

Dacrioadenite bilateral causada pelo vírus Epstein-Barr: relato de caso Epstein-Barr virus bilateral dacryoadenitis: case report

Directory of Open Access Journals (Sweden)

Bernardo Kaplan Moscovici

2009-12-01

Full Text Available Os autores apresentam um caso raro de dacrioadenite aguda bilateral associada à mononucleose. Paciente do sexo feminino, 27 anos, tinha aumento agudo da glândula lacrimal, bilateral, com sinais flogísticos. As alterações tomográficas e laboratoriais confirmaram o diagnóstico e o tratamento com esteróide sistêmico foi introduzido, com resolução completa dos sinais e sintomas. COMENTÁRIOS: A dacrioadenite é uma apresentação incomum da mononucleose infecciosa e pode minimizar outras manifestações desta doença. O diagnóstico de mononucleose deve ser considerado em casos de dacrioadenite aguda bilateral. Os esteróides sistêmicos contribuem para a resolução do quadro inflamatório.The authors present a rare case of acute bilateral dacryoadenitis in association with infectious mononucleosis. A 27 year-old woman had acute bilateral lacrimal gland enlargement with inflammatory signs. The CT scan findings and laboratorial investigations confirmed the diagnosis of infectious mononucleosis. The systemic treatment with intravenous steroids was initiated leading to complete remission of the signs and symptoms. COMMENTS: Dacryoadenitis is an uncommon manifestation of infectious mononucleosis and may minimize other signs of the disease. Mononucleosis has to be considered in acute dacryoadenitis cases. Systemic steroids contribute to the fast regression of inflammatory condition.

Teleoperated mobile robot (KAEROT) for inspection in nuclear facilities

Energy Technology Data Exchange (ETDEWEB)

Kim, Byung-Soo; Kim, Chang-Hoi; Hwang, Suk-Young; Kim, Seung-Ho; Lee, Jong-Min [Korea Atomic Energy Research Inst., Taejon (Korea, Republic of)

1994-12-31

A teleoperated mobile robot, named as KAEROT, has been developed for inspection and maintenance in nuclear facilities. It is composed of the planetary wheel-type mobile unit and 5 DOF manipulator one. The mobile unit is able to climb up and down stairs with high stability. This paper presents the kinematic analysis of KAEROT and the stair climbing algorithm. The proposed algorithm consists of two parts; one is to generate the moving path, and the other is to calculate the angular velocity of each wheel to follow up the generated reference path. Simulations and experiments on the irregular stairs have been carried out with the developed mobile robot. The proposed algorithm is proved to be very effective for inspection in nuclear facilities. The inclination angle of robot is maintained below 30.8deg while it is climbing up the stairs of a slope of 25deg. (author).

Teleoperated mobile robot (KAEROT) for inspection in nuclear facilities

International Nuclear Information System (INIS)

Kim, Byung-Soo; Kim, Chang-Hoi; Hwang, Suk-Young; Kim, Seung-Ho; Lee, Jong-Min

1994-01-01

A teleoperated mobile robot, named as KAEROT, has been developed for inspection and maintenance in nuclear facilities. It is composed of the planetary wheel-type mobile unit and 5 DOF manipulator one. The mobile unit is able to climb up and down stairs with high stability. This paper presents the kinematic analysis of KAEROT and the stair climbing algorithm. The proposed algorithm consists of two parts; one is to generate the moving path, and the other is to calculate the angular velocity of each wheel to follow up the generated reference path. Simulations and experiments on the irregular stairs have been carried out with the developed mobile robot. The proposed algorithm is proved to be very effective for inspection in nuclear facilities. The inclination angle of robot is maintained below 30.8deg while it is climbing up the stairs of a slope of 25deg. (author)

Bilateral acute iris transillumination: Case report

Directory of Open Access Journals (Sweden)

Cumali Degirmenci

2016-04-01

Full Text Available Bilateral acute iris transillumination (BAIT is a recently defined disease characterized with bilateral acute, severe pigment dispersion of iris and pupil sphincter paralysis. The etiopathogenesis of the disease is unknown, but antibiotics such as moxifloxacin, clarithromycin, viral infections, and fumigation therapies were considered as probable etiologic factors. A 33-year-old female was referred to our clinic for acute iridocyclitis refractory to azathioprine, colchicum and corticosteroid treatments. Ophthalmic examination revealed bilateral pigment dispersion, significant iris transillumination, heavy pigment deposition in iridocorneal angle, and elevated intraocular pressure. Upon systemic evaluation she was found to have bacterial urinary tract infection. BAIT is an important cause of pigment dispersion and clinicians must be vigilant for this condition to avoid unnecessary diagnostic tests and treatment.

The development of advanced robotics for the nuclear industry -The development of robotic system for the nuclear power plants-

Energy Technology Data Exchange (ETDEWEB)

Kim, Seung Hoh; Kim, Chang Heui; Kim, Byung Soo; Hwang, Suk Yong; Kim, Kee Hoh; Lee, Jae Kyung; Lee, Yung Kwang; Suh, Yong Chil; Lee, Yong Bum; Kim, Woong Kee; Park, Soon Yong [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

1995-07-01

The Advanced Robotics Department of the Korea Atomic Energy Research Institute (KAERI) is developing a Dexterous Manipulation System (DMS) and a teleoperated mobile robot, identified as KAEROT/ml, for use in nuclear power plants. The DMS is being developed for performing tasks such as the opening and closing of nozzle dam inside water chamber of steam generator. The DMS has two major subsystems; a master-slave 6 degrees of freedom (dof) manipulator and a support device. The master-slave arms are designed dissimilar kinematically and dynamically, and their functions are performed by a bilateral force-reflecting force control. The slave is a hydraulically powered arm with a 3 dof end effector, and is mounted on the top of the support device for nozzle dam operation. The support device guides the slave arm into the water chamber and supports it during its operation. The DMS can be operated either in teleoperated or supervisory control modes. The KAEROT/ml is designed to be used in emergency response applications such as monitoring and mapping radiation areas, handling radioactive materials and performing decontamination tasks. The KAEROT/ml equipped with four-omnidirectional planetary wheels has a 6 dof joint-controlled arm and is capable of ascending and descending stairs and navigating flat surface with zero turning radius. This report describes the mechanical design, features, modeling and control system of both the DMS and the KAEROT/ml. 209 figs, 49 pix, 69 tabs, 62 refs. (Author).

The development of advanced robotics for the nuclear industry -The development of robotic system for the nuclear power plants-

International Nuclear Information System (INIS)

Kim, Seung Hoh; Kim, Chang Heui; Kim, Byung Soo; Hwang, Suk Yong; Kim, Kee Hoh; Lee, Jae Kyung; Lee, Yung Kwang; Suh, Yong Chil; Lee, Yong Bum; Kim, Woong Kee; Park, Soon Yong

1995-07-01

The Advanced Robotics Department of the Korea Atomic Energy Research Institute (KAERI) is developing a Dexterous Manipulation System (DMS) and a teleoperated mobile robot, identified as KAEROT/ml, for use in nuclear power plants. The DMS is being developed for performing tasks such as the opening and closing of nozzle dam inside water chamber of steam generator. The DMS has two major subsystems; a master-slave 6 degrees of freedom (dof) manipulator and a support device. The master-slave arms are designed dissimilar kinematically and dynamically, and their functions are performed by a bilateral force-reflecting force control. The slave is a hydraulically powered arm with a 3 dof end effector, and is mounted on the top of the support device for nozzle dam operation. The support device guides the slave arm into the water chamber and supports it during its operation. The DMS can be operated either in teleoperated or supervisory control modes. The KAEROT/ml is designed to be used in emergency response applications such as monitoring and mapping radiation areas, handling radioactive materials and performing decontamination tasks. The KAEROT/ml equipped with four-omnidirectional planetary wheels has a 6 dof joint-controlled arm and is capable of ascending and descending stairs and navigating flat surface with zero turning radius. This report describes the mechanical design, features, modeling and control system of both the DMS and the KAEROT/ml. 209 figs, 49 pix, 69 tabs, 62 refs. (Author)

Simultaneous bilateral patellar tendon rupture.

Science.gov (United States)

Moura, Diogo Lino; Marques, José Pedro; Lucas, Francisco Manuel; Fonseca, Fernando Pereira

2017-01-01

Bilateral patellar tendon rupture is a rare entity, often associated with systemic diseases and patellar tendinopathy. The authors report a rare case of a 34-year-old man with simultaneous bilateral rupture of the patellar tendon caused by minor trauma. The patient is a retired basketball player with no past complaints of chronic knee pain and a history of steroid use. Surgical management consisted in primary end-to-end tendon repair protected temporarily with cerclage wiring, followed by a short immobilization period and intensive rehabilitation program. Five months after surgery, the patient was able to fully participate in sport activities.

Multilateral, regional and bilateral energy trade governance

Energy Technology Data Exchange (ETDEWEB)

Leal-Arcas, Rafael; Grasso, Costantino; Rios, Juan Alemany (Queen Mary Univ. of London (United Kingdom))

2014-12-01

The current international energy trade governance system is fragmented and multi-layered. Streamlining it for greater legal cohesiveness and international political and economic cooperation would promote global energy security. The current article explores three levels of energy trade governance: multilateral, regional and bilateral. Most energy-rich countries are part of the multilateral trading system, which is institutionalized by the World Trade Organization (WTO). The article analyzes the multilateral energy trade governance system by focusing on the WTO and energy transportation issues. Regionally, the article focuses on five major regional agreements and their energy-related aspects and examines the various causes that explain the proliferation of regional trade agreements, their compatibility with WTO law, and then provides several examples of regional energy trade governance throughout the world. When it comes to bilateral energy trade governance, this article only addresses the European Union’s (EU) bilateral energy trade relations. The article explores ways in which gaps could be filled and overlaps eliminated whilst remaining true to the high-level normative framework, concentrating on those measures that would enhance EU energy security.

Bilateral bone conduction devices: improved hearing ability in children with bilateral conductive hearing loss.

Science.gov (United States)

Dun, Catharina A J; Agterberg, Martijn J H; Cremers, Cor W R J; Hol, Myrthe K S; Snik, Ad F M

2013-01-01

The aim of the study was to investigate whether children with bilateral conductive hearing loss benefit from their second device (i.e., the bilateral bone conduction device [BCD]). Speech recognition in noise was assessed in 10 children fitted with bilateral BCDs during childhood. Speech recognition was measured in 2 conditions with both BCDs active. Spatial resolution was tested with the Minimum Audible Angle test in the bilateral and monaural listening conditions. Children demonstrated an improvement in speech recognition when speech was presented from the front and noise was presented from the right-hand side as compared with both speech and noise being presented from the front. The minimum audible angle decreased from 57° in the best monaural condition to 13° in the bilateral condition. The audiological outcomes demonstrate the advantage of bilateral BCD fitting in children with bilateral conductive hearing loss.

Transsynaptic neuronal degeneration of optic nerves associated with bilateral occipital lesions

Directory of Open Access Journals (Sweden)

Sachdev Mahipal

1990-01-01

Full Text Available A case is reported of a 9-year old male who presented with abnormal behaviour and progressive diminution of vision. Pupils were middilated in both eyes but the pupillary reflexes were preserved. Fundus examination revealed a bilateral optic atrophy and radiological investigations showed a bilateral occipital calcification. We hereby document a case of retrograde transsynaptic neuronal degeneration of the visual system secondary to bilateral occipital lesions. Transsynapptic neuronal degeneration of optic nerves consequent to occipital lobe lesions is a rare phenomenon. Experimentally occipital lobe ablation in non-human primates has been shown to result in optic atrophy. Herein, we document a case of retrograde transsynaptic neuronal degeneration of the visual system secondary to bilateral occipital lesions.

Experimental Evaluation of Novel Master-Slave Configurations for Position Control under Random Network Delay and Variable Load for Teleoperation

Directory of Open Access Journals (Sweden)

Ahmet Kuzu

2014-01-01

Full Text Available This paper proposes two novel master-slave configurations that provide improvements in both control and communication aspects of teleoperation systems to achieve an overall improved performance in position control. The proposed novel master-slave configurations integrate modular control and communication approaches, consisting of a delay regulator to address problems related to variable network delay common to such systems, and a model tracking control that runs on the slave side for the compensation of uncertainties and model mismatch on the slave side. One of the configurations uses a sliding mode observer and the other one uses a modified Smith predictor scheme on the master side to ensure position transparency between the master and slave, while reference tracking of the slave is ensured by a proportional-differentiator type controller in both configurations. Experiments conducted for the networked position control of a single-link arm under system uncertainties and randomly varying network delays demonstrate significant performance improvements with both configurations over the past literature.

Simultaneous bilateral patellar tendon rupture

Directory of Open Access Journals (Sweden)

Diogo Lino Moura

Full Text Available ABSTRACT Bilateral patellar tendon rupture is a rare entity, often associated with systemic diseases and patellar tendinopathy. The authors report a rare case of a 34-year-old man with simultaneous bilateral rupture of the patellar tendon caused by minor trauma. The patient is a retired basketball player with no past complaints of chronic knee pain and a history of steroid use. Surgical management consisted in primary end-to-end tendon repair protected temporarily with cerclage wiring, followed by a short immobilization period and intensive rehabilitation program. Five months after surgery, the patient was able to fully participate in sport activities.

Bilateral cerebral hemispheric infarction associated with sildenafil citrate (Viagra) use.

Science.gov (United States)

Kim, K-K; Kim, D G; Ku, Y H; Lee, Y J; Kim, W-C; Kim, O J; Kim, H S

2008-03-01

Sildenafil citrate (Viagra) is one of the frequently prescribed drugs for men with erectile dysfunction. We describe a 52-year-old man with bilateral middle cerebral artery (MCA) territory infarction after sildenafil use. He ingested 100 mg of sildenafil and about 1 h later, he complained of chest discomfort, palpitation and dizziness followed by mental obtundation, global aphasia and left hemiparesis. Brain magnetic resonance imaging documented acute bilateral hemispheric infarction, and cerebral angiography showed occluded bilateral MCA. Despite significant bilateral MCA stenosis and cerebral infarction, systemic hypotension persisted for a day. We presume that cerebral infarction was caused by cardioembolism with sildenafil use.

Analysis of remote operating systems for space-based servicing operations. Volume 2: Study results

Science.gov (United States)

1985-01-01

The developments in automation and robotics have increased the importance of applications for space based servicing using remotely operated systems. A study on three basic remote operating systems (teleoperation, telepresence and robotics) was performed in two phases. In phase one, requirements development, which consisted of one three-month task, a group of ten missions were selected. These included the servicing of user equipment on the station and the servicing of the station itself. In phase two, concepts development, which consisted of three tasks, overall system concepts were developed for the selected missions. These concepts, which include worksite servicing equipment, a carrier system, and payload handling equipment, were evaluated relative to the configurations of the overall worksite. It is found that the robotic/teleoperator concepts are appropriate for relatively simple structured tasks, while the telepresence/teleoperator concepts are applicable for missions that are complex, unstructured tasks.

Prolapsed bilateral ureteroceles leading to intermittent outflow obstruction.

LENUS (Irish Health Repository)

Stunell, H

2012-02-01

A ureterocele refers to a cystic dilatation of the distal ureter. It may be unilateral or bilateral and may be associated with a duplex system in some cases. We present an unusual case where a young patient was found to have large bilateral ureteroceles which prolapsed into the urethra, causing intermittent incontinence and obstruction. We discuss the case and review the literature concerning this rare anomaly.

Rash with DERMABOND PRINEO Skin Closure System Use in Bilateral Reduction Mammoplasty: A Case Series

OpenAIRE

R. W. Knackstedt; J. A. Dixon; P. J. O’Neill; F. A. Herrera

2015-01-01

Background. Bilateral reduction mammoplasty is a common plastic surgery procedure that can be complicated by unfavorable scar formation along incision sites. Surgical adhesives can be utilized as an alternative or as an adjunct to conventional suture closures to help achieve good wound tension and provide an adequate barrier with excellent cosmesis. The recently introduced DERMABOND PRINEO Skin Closure System Skin Closure System combines the skin adhesive 2-octyl cyanoacrylate with a self-ad...

Bilateral herpes zoster

OpenAIRE

Singh K; Bajaj A; Dwivedi N; Merchery A

1993-01-01

A case of bilateral herpes zoster of lumbosacral region is reported in association with diabetes mellitus in a 55 years old female. The case is of interest due to bilateral distribution which is rare and sacral region involvement which is quite uncommon.

Security cost allocation under combined bilateral-pool market dispatch

International Nuclear Information System (INIS)

Abdullah, M.P.; Hassan, M.Y.; Hussin, F.

2008-01-01

Most electricity markets around the world are a combination of bilateral and pool markets, such as NordPool and NYPOOL. In these models, market participants bid into the pool and also make bilateral contracts with each other. This paper addressed the issue of congestion management and security cost allocation in a power pool market model. The basic idea of security cost allocation is to divide the incurred security cost due to congestion relief into pool and bilateral market based on their flow contribution to the congested line. A newly proposed security cost allocation strategy of the combined bilateral-pool market was also presented along with case studies using IEEE-14 bus system that tested the proposed method. Using the proposed method, it was shown that security costs are allocated to market participants at different prices which reflect the load contribution to the security problem. This solves the problem of the uniform security cost allocation in a pure pool market system having uniform pricing, and provides a proper security signal to market participants. 11 refs., 3 tabs., 4 figs

Bilateral Testicular Tumors Resulting in Recurrent Cushing Disease After Bilateral Adrenalectomy

NARCIS (Netherlands)

Puar, T.; Engels, M.; Herwaarden, A.E. van; Sweep, F.C.; Hulsbergen-van de Kaa, C.A.; Kamphuis-van Ulzen, K.; Chortis, V.; Arlt, W.; Stikkelbroeck, N.; Claahsen-van der Grinten, H.L.; Hermus, A.R.M.M.

2017-01-01

Context: Recurrence of hypercortisolism in patients after bilateral adrenalectomy for Cushing disease is extremely rare. Patient: We present a 27-year-old man who previously underwent bilateral adrenalectomy for Cushing disease with complete clinical resolution. Cushingoid features recurred 12 years

Bilateral herpes zoster

Directory of Open Access Journals (Sweden)

Singh K

1993-01-01

Full Text Available A case of bilateral herpes zoster of lumbosacral region is reported in association with diabetes mellitus in a 55 years old female. The case is of interest due to bilateral distribution which is rare and sacral region involvement which is quite uncommon.

Decontamination and concrete core sampling by teleoperated robot at Fukushima Daiichi reactor buildings

International Nuclear Information System (INIS)

Watanabe, Masaru; Onitsuka, Hironori; Shimonabe, Noriaki; Fujita, Jun; Matsumura, Takumi; Okumura, Atsushi

2015-01-01

For decommissioning of Fukushima daiichi nuclear power station, reduction of the dose equivalent rates inside the reactor buildings is an important issue. Concrete core sampling from the buildings to investigate the contamination is necessary for study about effective decontamination. However, dose rate inside the reactor buildings is very high. For example, dose rate of 1st floor on the Unit 1 is 1.2 - 1820 [mSv / h], the Unit 2 is 2.5 - 220 [mSv / h] and Unit 3 is 2.2 - 4780 [mSv / h]. So it is difficult for workers to work long hours. Therefore, a teleoperated robot, named 'MHI-MEISTeR (Mitsubishi Heavy Industries - Maintenance Equipment Integrated System of Telecontrol Robot)', has been developed to conduct operations like concrete core samples from the reactor buildings. Actually, some concrete core samples from Fukushima daiichi were taken by MHI-MEISTeR. In addition, MHI-MEISTeR is designed as a versatile robot, and so it can conduct suction / blast decontamination works as well as concrete core sampling. The above operations were performed by MHI-MEISTeR in Fukushima daiichi nuclear power station. (author)

Bilateral Supernumerary Kidney: A Very Rare Presentation

International Nuclear Information System (INIS)

Keskin, Suat; Batur, Abdussamet; Keskin, Zeynep; Koc, Abdulkadir; Firat Ozcan, Irfan

2014-01-01

To our knowledge, bilateral supernumerary kidney is a very rare renal abnormality and there are five cases presented in the literature. It is difficult to diagnose supernumerary kidney and clinicians have not detected most cases preoperatively. Laboratory and imaging studies were acquired and carefully examined. The normal laboratory tests were found. Emergency ultrasonography was performed and they revealed no signs of parenchymal abnormality in both kidneys. Serial imaging study including enhanced computed tomography (CT) was performed. An imaging study identified bilateral supernumerary kidney with expanded collecting systems. On each side, significant rotation anomaly was found. In addition, there were two different renal arteries originating from the aorta. This report presents radiological determinations of supernumerary kidney bilaterally in a young man. We think that CT commonly appears to be enough for the diagnosis of supernumerary kidneys

Bilateral breast carcinoma

International Nuclear Information System (INIS)

Kim, Eung Jo; Oh, Ki Keun

1990-01-01

We evaluate 311 breast cancer patients admitted to Yong Dong Severance Hospital Between October 1st 1985 and July 31th 1989, and were able to obtain the following conclusions. 1) There were 14(4.5%) bilateral breast cancers among the 311 confirmed breast cancers. 2) Among the bilateral breast cancers, 5(31%) were synchronous and 9(69%) metachronous. 3) Average interval between the first and the second breast cancer in metachronous cancers was 3.8 year(1-15 years). 4) Bilateral breast cancer was most prevalent in the fifth decade (6/14) with the mean age of 47 years. 5) Film mammogram and sonomammogram showed findings of typical breast malignancies. There was no additional specific findings for each cancer in bilateral breast cancers which was different from unilateral cancers. Therefor, in the patients with unilateral breast cancer, possibility of the second lesion in the contralateral side must be considered and a close follow up observation should be done for at least 3 years

A SECOND CASE OF BILATERAL RHEGMATOGENOUS RETINAL DETACHMENTS REPAIRED WITH SIMULTANEOUS BILATERAL PNEUMATIC RETINOPEXY.

Science.gov (United States)

Rubin, Uriel; De Jager, Cornelis; Zakour, Moayed; Gonder, J Thomas

2017-01-01

To present a case of a patient with simultaneous bilateral retinal detachments treated successfully with bilateral pneumatic retinopexy. Case report. This is a case of an otherwise healthy 49-year-old woman with no remarkable ocular history that presented with simultaneous phakic superior bilateral rhegmatogenous retinal detachments. Treatment on the day of presentation included laser retinopexy of the inferior lattice degeneration in the left eye and bilateral intravitreal injection of 0.4 cc of 100% C3F8 gas preceded by topical anesthesia. After 48 hours, both retinas were completely reattached, and bilateral laser retinopexy was performed to the superior tears. After a review of the literature, the authors could find only two reported cases of simultaneous bilateral retinal detachments treated successfully with pneumatic retinopexy. This is not only a cost-effective procedure but also allows treatment when there is no immediate operating room availability or a when a quick referral for surgery is not possible.

Stabilization of Bilateral Progressive Rheumatoid Corneal Melt with Infliximab

Directory of Open Access Journals (Sweden)

Sheelah F. Antao

2012-01-01

Results. A patient with rheumatoid arthritis presented with bilateral PUK following a 2-month history of ocular discomfort and redness. His systemic prednisolone (PDN and methotrexate (MTX were increased and, despite an initial favorable response, bilateral recurrent corneal perforations ensued. Both eyes underwent cyanoacrylate glue repair, amniotic membrane transplantation (AMT, and penetrating keratoplasty (PKP. Recurrence of the disease and bilateral perforations of the second PKP in both eyes prompted administration of intravenous infliximab immediately after the fourth PKP. The disease activity rapidly settled in both eyes, and at eighteen-month followup, after 12 infliximab infusions, the PUK remains quiescent with no further graft thinning or perforation. Conclusion. Infliximab can be used to arrest the progression of severe bilateral rheumatoid PUK in cases that are refractory to conventional treatment.

Quantitative assessment of paretic limb dexterity and interlimb coordination during bilateral arm rehabilitation training.

Science.gov (United States)

Xu, Chang; Li, Siyi; Wang, Kui; Hou, Zengguang; Yu, Ningbo

2017-07-01

In neuro-rehabilitation after stroke, the conventional constrained induced movement therapy (CIMT) has been well-accepted. Existing bilateral trainings are mostly on mirrored symmetrical motion. However, complementary bilateral movements are dominantly involved in activities of daily living (ADLs), and functional bilateral therapies may bring better skill transfer from trainings to daily life. Neurophysiological evidence is also growing. In this work, we firstly introduce our bilateral arm training system realized with a haptic interface and a motion sensor, as well as the tasks that have been designed to train both the manipulation function of the paretic arm and coordination of bilateral upper limbs. Then, we propose quantitative measures for functional assessment of complementary bilateral training performance, including kinematic behavior indices, smoothness, submovement and bimanual coordination. After that, we describe the experiments with healthy subjects and the results with respect to these quantitative measures. Feasibility and sensitivity of the proposed indices were evaluated through comparison of unilateral and bilateral training outcomes. The proposed bilateral training system and tasks, as well as the quantitative measures, have been demonstrated effective for training and assessment of unilateral and bilateral arm functions.

Developments of STR project in the scope of teleoperation handling robotic for the operation in Spanish nuclear facilities; Desarrollos del proyecto SRT en el area de manipulacion robotica teleoperada para la operacion de las instalaciones nucleares espanolas

Energy Technology Data Exchange (ETDEWEB)

Bielza, M [ENDESA (Spain); Gomez Santamaria, J [IBERDROLA (Spain); Izquierdo, J A [C.N. COFRENTES (Spain); Martinez, S [C.N. ASCO (Spain); Linares, F [ENSA (Spain); Avello, A [CEIT (Spain); Gago, M J [IBRINCO (Spain)

1998-12-01

The main objective of the Teleoperated Robotic Systems project (SRT) is the development of teleoperated robotic systems for use in the inspection, surveillance and maintenance operations in nuclear and radioactive installations. These systems make possible the reduction of the individual and collective doses of the workers that undertake these operations, as well as an increase of plant availability as it is possible to carry out specific tasks of inspection and surveillance in high radiation dose areas without having to reduce the power of the installation. This project started in 1995, deciding to priorize the inspection equipment in a first phase. When this work were advanced, the development of the manipulation activities was carried out to being consider the nuclear installations needs. As a result of this work, the manipulation requirements were elaborated in order to prepare the beginning technical specifications to design the equipment s. These developments are based on a fixed manipulator which is located closed to the equipment that we want to repair, and an arm manipulator which moves by caterpillars, it is easier to control than others; and the navigation system which allows the robot self-locating in the complex area. In this paper the conclusions about the manipulation requirements are described, as well as the state of the manipulation prototype. (Author)

Bilateral Supernumerary Kidney: A Very Rare Presentation

Science.gov (United States)

Keskin, Suat; Batur, Abdussamet; Keskin, Zeynep; Koc, Abdulkadir; Firat Ozcan, Irfan

2014-01-01

To our knowledge, bilateral supernumerary kidney is a very rare renal abnormality and there are five cases presented in the literature. It is difficult to diagnose supernumerary kidney and clinicians have not detected most cases preoperatively. Laboratory and imaging studies were acquired and carefully examined. The normal laboratory tests were found. Emergency ultrasonography was performed and they revealed no signs of parenchymal abnormality in both kidneys. Serial imaging study including enhanced computed tomography (CT) was performed. An imaging study identified bilateral supernumerary kidney with expanded collecting systems. On each side, significant rotation anomaly was found. In addition, there were two different renal arteries originating from the aorta. This report presents radiological determinations of supernumerary kidney bilaterally in a young man. We think that CT commonly appears to be enough for the diagnosis of supernumerary kidneys. PMID:25780543

Scaled Bilateral Teleoperation Using Discrete-Time Sliding-Mode Controller

NARCIS (Netherlands)

Khan, S.; Sabanovic, A.; Nergiz, A.O.

2009-01-01

In this paper, the design of a discrete-time sliding-mode controller based on Lyapunov theory is presented along with a robust disturbance observer and is applied to a piezostage for high-precision motion. A linear model of a piezostage was used with nominal parameters to compensate the disturbance

Bilateral acute retinal necrosis associated with bilateral uveal effusion in an immunocompetent patient: A challenging association

Directory of Open Access Journals (Sweden)

S Bala Murugan

2018-01-01

Full Text Available Bilateral uveal effusion syndrome associated with bilateral acute retinal necrosis is a diagnostic and therapeutic challenge. A 52 year old man presented with bilateral angle closure with choroidal detachment. With restricted fundus view, parenteral steroid was started. During close follow up bilateral discrete areas of peripheral retinitis were noted. Parenteral steroids were promptly stopped and parenteral antivirals with oral steroids were continued. It showed healing response with nil recurrences till last follow up. Aggressive treatment of bilateral uveal effusion with parenteral steroids can cause progression of bilateral acute retinal necrosis leading to phthisis bulbi. However early diagnosis, prompt intervention and close follow up are the key elements to therapeutic success even during diagnostic surprises and avoid costly mistakes.

38 CFR 4.26 - Bilateral factor.

Science.gov (United States)

2010-07-01

... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Bilateral factor. 4.26... DISABILITIES General Policy in Rating § 4.26 Bilateral factor. When a partial disability results from disease... disability. The bilateral factor will be applied to such bilateral disabilities before other combinations are...

High Performance, Three-Dimensional Bilateral Filtering

International Nuclear Information System (INIS)

Bethel, E. Wes

2008-01-01

Image smoothing is a fundamental operation in computer vision and image processing. This work has two main thrusts: (1) implementation of a bilateral filter suitable for use in smoothing, or denoising, 3D volumetric data; (2) implementation of the 3D bilateral filter in three different parallelization models, along with parallel performance studies on two modern HPC architectures. Our bilateral filter formulation is based upon the work of Tomasi [11], but extended to 3D for use on volumetric data. Our three parallel implementations use POSIX threads, the Message Passing Interface (MPI), and Unified Parallel C (UPC), a Partitioned Global Address Space (PGAS) language. Our parallel performance studies, which were conducted on a Cray XT4 supercomputer and aquad-socket, quad-core Opteron workstation, show our algorithm to have near-perfect scalability up to 120 processors. Parallel algorithms, such as the one we present here, will have an increasingly important role for use in production visual analysis systems as the underlying computational platforms transition from single- to multi-core architectures in the future.

High Performance, Three-Dimensional Bilateral Filtering

Energy Technology Data Exchange (ETDEWEB)

Bethel, E. Wes

2008-06-05

Image smoothing is a fundamental operation in computer vision and image processing. This work has two main thrusts: (1) implementation of a bilateral filter suitable for use in smoothing, or denoising, 3D volumetric data; (2) implementation of the 3D bilateral filter in three different parallelization models, along with parallel performance studies on two modern HPC architectures. Our bilateral filter formulation is based upon the work of Tomasi [11], but extended to 3D for use on volumetric data. Our three parallel implementations use POSIX threads, the Message Passing Interface (MPI), and Unified Parallel C (UPC), a Partitioned Global Address Space (PGAS) language. Our parallel performance studies, which were conducted on a Cray XT4 supercomputer and aquad-socket, quad-core Opteron workstation, show our algorithm to have near-perfect scalability up to 120 processors. Parallel algorithms, such as the one we present here, will have an increasingly important role for use in production visual analysis systems as the underlying computational platforms transition from single- to multi-core architectures in the future.

Pregnancy following bilateral salpingectomy

DEFF Research Database (Denmark)

Oturai, Annette Bang

2008-01-01

This report presents a rare case of spontaneous pregnancy following bilateral salpingectomy. A woman with a history of bilateral salpingectomy was admitted to hospital because of abdominal pain and positive urine HCG. Surprisingly, ultrasound confirmed a live intrauterine fetus. The pregnancy...... was unwanted, and the woman decided to terminate the pregnancy. She was offered diagnostic examination to localise a potential fistula, but she declined. In a MEDLINE search of English literature this is only the second case of spontaneous pregnancy following bilateral salpingectomy Udgivelsesdato: 2008/4/21...

Bilateral cerebrovascular accidents in incontinentia pigmenti.

Science.gov (United States)

Fiorillo, Loretta; Sinclair, D Barry; O'Byrne, Mary L; Krol, Alfons L

2003-07-01

Incontinentia Pigmenti is an X-linked dominant neurocutaneous disorder with central nervous system manifestations in 30% of cases, including seizures and mental retardation. Ischemic or hemorrhagic cerebrovascular accidents have been reported rarely in incontinentia pigmenti. Chart review and literature search was performed following identification of the index case. We describe a patient with incontinentia pigmenti who developed bilateral cerebrovascular accidents in the neonatal period, with resultant severe neurologic sequelae. This is the second reported case of bilateral cerebrovascular accidents in a patient with incontinentia pigmenti. This finding may be secondary to cerebrovascular anomalies, similar to those observed in the retina. Recognition of cerebrovascular accidents as a complication of incontinentia pigmenti will hopefully lead to earlier recognition and treatment.

Bilateral Rhegmatogenous Retinal Detachment during External Beam Radiotherapy

Directory of Open Access Journals (Sweden)

Takako Hidaka

2016-06-01

Full Text Available Herein, we report a case of nontraumatic bilateral rhegmatogenous retinal detachment (RRD during external beam radiotherapy for nonocular tumor, presented as an observational case study in conjunction with a review of the relevant literature. A 65-year-old male was referred to our hospital due to bilateral RRD. He underwent a biopsy for a tumor of the left frontal lobe 4 months prior to presentation, and the tumor had been diagnosed as primary central nerve system B-cell type lymphoma. He received chemotherapy and external beam radiotherapy for 1 month. There were no traumatic episodes. Bilateral retinal detachment occurred during a series of radiotherapies. Simultaneous nontraumatic bilateral retinal detachment is rare. The effects of radiotherapy on ocular functionality, particularly in cases involving retinal adhesion and vitreous contraction, may include RRD. Thus, it is necessary to closely monitor the eyes of patients undergoing radiotherapy, particularly those undergoing surgery for retinal detachment and those with a history of photocoagulation for retinal tears, a relevant family history, or risk factors known to be associated with RRD.

Modular telerobot control system for accident response

Science.gov (United States)

Anderson, Richard J. M.; Shirey, David L.

1999-08-01

The Accident Response Mobile Manipulator System (ARMMS) is a teleoperated emergency response vehicle that deploys two hydraulic manipulators, five cameras, and an array of sensors to the scene of an incident. It is operated from a remote base station that can be situated up to four kilometers away from the site. Recently, a modular telerobot control architecture called SMART was applied to ARMMS to improve the precision, safety, and operability of the manipulators on board. Using SMART, a prototype manipulator control system was developed in a couple of days, and an integrated working system was demonstrated within a couple of months. New capabilities such as camera-frame teleoperation, autonomous tool changeout and dual manipulator control have been incorporated. The final system incorporates twenty-two separate modules and implements seven different behavior modes. This paper describes the integration of SMART into the ARMMS system.

Bilateral persistent hyperplastic primary vitreous

Directory of Open Access Journals (Sweden)

Jain Tarun

2009-01-01

Full Text Available A case of bilateral persistent hyperplastic primary vitreous (PHPV in a 3-month-old male infant, who had bilateral leukokoria, is presented. The child was referred for imaging with a clinical suspicion of retinoblastoma. Gray-scale ultrasound evaluation revealed an echogenic band in the posterior segment of both globes, extending from the posterior surface of the lens capsule to the optic disc. Doppler examination revealed the presence of arterial flow in the band in both globes. Associated echogenic hemorrhage was also seen, which was confirmed by computed tomography. Most cases of PHPV are sporadic and unilateral, and bilateral PHPV is rare. The imaging features in this case suggest the diagnosis of bilateral PHPV and differentiate it from retinoblastoma. This entity, although infrequent, should be considered in the differential diagnosis while evaluating bilateral leukokoria.

Idiopathic bilateral male breast abscess.

Science.gov (United States)

Sinha, Rajan Kumar; Sinha, Mithilesh Kumar; Gaurav, Kumar; Kumar, Amar

2014-03-10

A 38-year-old man presented with bilateral breast swelling, along with pain and redness for 7 days. Bilateral axillary nodes were also palpable; which were multiple and discrete. A provisional diagnosis of bilateral breast abscess was made with suspicion of underlying malignancy. Incision and drainage through subareolar incision was performed and the adjoining tissue was excised and sent for histopathological examination.

A case of systemic lupus erythematosus presenting as bilateral avascular necrosis of femur.

Science.gov (United States)

Adikari, Madura; Gunawardane, Aloka; Illangantilaka, Sachithra; Atukorale, Himantha; Rubasinghe, Jeevanie

2016-08-05

Avascular necrosis occur as a result of diverse etiology. Chronic inflammatory conditions such as systemic lupus erythematosus considered as a recognize cause. Many cases were reported in systemic lupus erythematosus after treating with corticosteroids. We report a case of a corticosteroid naïve patient presented as bilateral avascular necrosis of femoral head and later progressed to a case of systemic lupus erythematosus. A 26 year old lady presented with right sided hip pain and diagnosed as avascular necrosis of the femoral head. After 6 months she presented a similar pain in left hip, which revealed avascular necrosis of left femoral head as well. A probable cause for her clinical presentation could not be found after extensive clinical and laboratory evaluation. Patient reported high erythrocyte sedimentation rate persistently, and over the next few years progressed as a case of systemic lupus erythematosus. Above case illustrated avascular necrosis could be an early musculoskeletal manifestation of systemic lupus erythematosus even in the absence of corticosteroid administration.

Bilateral Endoscopic Medial Maxillectomy for Bilateral Inverted Papilloma

Directory of Open Access Journals (Sweden)

Satoru Kodama

2012-01-01

Full Text Available Inverted papilloma (IP is a benign tumor of the nasal cavity and paranasal sinuses that is unilateral in most cases. Bilateral IP, involving both sides of the nasal cavity and sinuses, is extremely rare. This paper describes a large IP that filled in both sides of the nasal cavity and sinuses, mimicking association with malignancy. The tumor was successfully treated by bilateral endoscopic medial maxillectomy (EMM. The patient is without evidence of the disease 24 months after surgery. If preoperative diagnosis does not confirm the association with malignancy in IP, endoscopic sinus surgery (ESS should be selected, and ESS, including EMM, is a good first choice of the treatment for IP.

Bilateral Endoscopic Medial Maxillectomy for Bilateral Inverted Papilloma

Science.gov (United States)

Kodama, Satoru; Kawano, Toshiaki; Suzuki, Masashi

2012-01-01

Inverted papilloma (IP) is a benign tumor of the nasal cavity and paranasal sinuses that is unilateral in most cases. Bilateral IP, involving both sides of the nasal cavity and sinuses, is extremely rare. This paper describes a large IP that filled in both sides of the nasal cavity and sinuses, mimicking association with malignancy. The tumor was successfully treated by bilateral endoscopic medial maxillectomy (EMM). The patient is without evidence of the disease 24 months after surgery. If preoperative diagnosis does not confirm the association with malignancy in IP, endoscopic sinus surgery (ESS) should be selected, and ESS, including EMM, is a good first choice of the treatment for IP. PMID:22953103

Bilateral metachronous periosteal tibial amyloid tumors

International Nuclear Information System (INIS)

Murata, H.; Kusuzaki, Katsuyuki; Hashiguchi, S.; Ueda, Hidetaka; Hirasawa, Yasusuke

2000-01-01

Localized primary periosteal amyloid tumors are extremely rare. A case of bilateral tibial amyloid tumor is presented. A 62-year-old woman initially presented with a painful mass in the anterior aspect of the right leg. There was no evidence of underlying systemic disease, including chronic infection or malignancy. Based on the results of resistance with Congo red staining to treatment with potassium permanganate and positivity for kappa light chain, we classified this particular case as AL-type amyloidosis. The patient noticed a swelling in the opposite leg 2 years later. The second tumor was also an AL-type amyloidoma. Amyloid tumors are generally solitary. This is the first case of bilateral periosteal amyloid tumors of the AL-type occurring in the tibiae. (orig.)

Monte Carlo simulation based reliability evaluation in a multi-bilateral contracts market

International Nuclear Information System (INIS)

Goel, L.; Viswanath, P.A.; Wang, P.

2004-01-01

This paper presents a time sequential Monte Carlo simulation technique to evaluate customer load point reliability in multi-bilateral contracts market. The effects of bilateral transactions, reserve agreements, and the priority commitments of generating companies on customer load point reliability have been investigated. A generating company with bilateral contracts is modelled as an equivalent time varying multi-state generation (ETMG). A procedure to determine load point reliability based on ETMG has been developed. The developed procedure is applied to a reliability test system to illustrate the technique. Representing each bilateral contract by an ETMG provides flexibility in determining the reliability at various customer load points. (authors)

Adenocarcinoma of the ethmoid following radiotherapy for bilateral retinoblastoma

Energy Technology Data Exchange (ETDEWEB)

Rowe, L.D.; Lane, R.; Snow, J.B. Jr.

1980-01-01

Adenocarcinoma of the ethmoid sinus is rare, representing only 4 to 8% of malignancies of the paranasal sinuses. An extraordinary case of papillary adenocarcinoma of the ethmoid sinus arising 30 years following high-dose radiotherapy for bilateral retinoblastoma is presented. Second fatal mesenchymal and epithelial primaries have been described in 8.5% of patients with bilateral retinoblastomas previously treated with radiotherapy; however, papillary adenocarcinoma arising within the paranasal sinuses has not been reported. Aggressive treatment including partial maxillectomy, radical pansinusectomy, radical neck dissection followed by regional radiotherapy and systemic chemotherapy failed to prevent the development of fatal hepatic metastases. The high incidence of second fatal primary neoplasms in patients with bilateral retinoblastomas receiving radiation suggests an innate susceptibility that may add to the risk of radiotherapy.

Adenocarcinoma of the ethmoid following radiotherapy for bilateral retinoblastoma

International Nuclear Information System (INIS)

Rowe, L.D.; Lane, R.; Snow, J.B. Jr.

1980-01-01

Adenocarcinoma of the ethmoid sinus is rare, representing only 4 to 8% of malignancies of the paranasal sinuses. An extraordinary case of papillary adenocarcinoma of the ethmoid sinus arising 30 years following high-dose radiotherapy for bilateral retinoblastoma is presented. Second fatal mesenchymal and epithelial primaries have been described in 8.5% of patients with bilateral retinoblastomas previously treated with radiotherapy; however, papillary adenocarcinoma arising within the paranasal sinuses has not been reported. Aggressive treatment including partial maxillectomy, radical pansinusectomy, radical neck dissection followed by regional radiotherapy and systemic chemotherapy failed to prevent the development of fatal hepatic metastases. The high incidence of second fatal primary neoplasms in patients with bilateral retinoblastomas receiving radiation suggests an innate susceptibility that may add to the risk of radiotherapy

Catastrophic Antiphospholipid Syndrome Presenting as Bilateral Central Retinal Artery Occlusions

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Steven S. Saraf

2015-01-01

Full Text Available A previously healthy 22-year-old African American woman presented with bilateral vision loss associated with headache. Her ocular examination was significant for bilateral retinal arterial “boxcarring,” retinal whitening, retinal hemorrhages, and cherry red spots. She was diagnosed with bilateral central retinal artery occlusions and was hospitalized due to concomitant diagnosis of stroke and hypercoagulable state. She was also found to be in heart failure and kidney failure. Rheumatology was consulted and she was diagnosed with catastrophic antiphospholipid syndrome in association with systemic lupus erythematosus. Approximately 7 months after presentation, the patient’s vision improved and remained stable at 20/200 and 20/80.

Bilateral, independent juvenile nasopharyngeal angiofibroma

DEFF Research Database (Denmark)

Mørkenborg, Marie-Louise; Frendø, M; Stavngaard, T

2015-01-01

BACKGROUND: Juvenile nasopharyngeal angiofibroma is a benign, vascular tumour that primarily occurs in adolescent males. Despite its benign nature, aggressive growth patterns can cause potential life-threatening complications. Juvenile nasopharyngeal angiofibroma is normally unilateral, originating...... from the sphenopalatine artery, but bilateral symptoms can occur if a large tumour extends to the contralateral side of the nasopharynx. This paper presents the first reported case of true bilateral extensive juvenile nasopharyngeal angiofibroma involving clinically challenging pre-surgical planning...... embolisation. Radical removal performed as one-step, computer-assisted functional endoscopic sinus surgery was performed. The follow-up period was uncomplicated. CONCLUSION: This case illustrates the importance of suspecting bilateral juvenile nasopharyngeal angiofibroma in patients presenting with bilateral...

BILATERAL SINGLE SESSION URETEROSCOPY FOR URETERAL ...

African Journals Online (AJOL)

Objectives: To determine the feasibility, safety and success rate of bilateral single session rigid retrograde ureteroscopy (URS) for bilateral ureteral calculi. Patients and Methods: Thirty-five patients underwent bilateral single session ureteroscopic calculus removal. Results: Out of 70 renal units in 35 patients treated, ...

A system-level approach to automation research

Science.gov (United States)

Harrison, F. W.; Orlando, N. E.

1984-01-01

Automation is the application of self-regulating mechanical and electronic devices to processes that can be accomplished with the human organs of perception, decision, and actuation. The successful application of automation to a system process should reduce man/system interaction and the perceived complexity of the system, or should increase affordability, productivity, quality control, and safety. The expense, time constraints, and risk factors associated with extravehicular activities have led the Automation Technology Branch (ATB), as part of the NASA Automation Research and Technology Program, to investigate the use of robots and teleoperators as automation aids in the context of space operations. The ATB program addresses three major areas: (1) basic research in autonomous operations, (2) human factors research on man-machine interfaces with remote systems, and (3) the integration and analysis of automated systems. This paper reviews the current ATB research in the area of robotics and teleoperators.

Variability of gait, bilateral coordination, and asymmetry in women with fibromyalgia.

Science.gov (United States)

Heredia-Jimenez, J; Orantes-Gonzalez, E; Soto-Hermoso, V M

2016-03-01

To analyze how fibromyalgia affected the variability, asymmetry, and bilateral coordination of gait walking at comfortable and fast speeds. 65 fibromyalgia (FM) patients and 50 healthy women were analyzed. Gait analysis was performed using an instrumented walkway (GAITRite system). Average walking speed, coefficient of variation (CV) of stride length, swing time, and step width data were obtained and bilateral coordination and gait asymmetry were analyzed. FM patients presented significantly lower speeds than the healthy group. FM patients obtained significantly higher values of CV_StrideLength (p=0.04; pGait asymmetry only showed significant differences in the fast condition. FM patients walked more slowly and presented a greater variability of gait and worse bilateral coordination than healthy subjects. Gait asymmetry only showed differences in the fast condition. The variability and the bilateral coordination were particularly affected by FM in women. Therefore, variability and bilateral coordination of gait could be analyzed to complement the gait evaluation of FM patients. Copyright © 2016 Elsevier B.V. All rights reserved.

Acute Bilateral Superior Branch Vestibular Neuropathy

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Dario A. Yacovino

2018-05-01

Full Text Available The rapid onset of a bilateral vestibular hypofunction (BVH is often attributed to vestibular ototoxicity. However, without any prior exposure to ototoxins, the idiopathic form of BVH is most common. Although sequential bilateral vestibular neuritis (VN is described as a cause of BVH, clinical evidence for simultaneous and acute onset bilateral VN is unknown. We describe a patient with an acute onset of severe gait ataxia and oscillopsia with features compatible with acute BVH putatively due to a bilateral VN, which we serially evaluated with clinical and laboratory vestibular function testing over the course of 1 year. Initially, bilateral superior and horizontal semicircular canals and bilateral utricles were impaired, consistent with damage to both superior branches of each vestibular nerve. Hearing was spared. Only modest results were obtained following 6 months of vestibular rehabilitation. At a 1-year follow-up, only the utricular function of one side recovered. This case is the first evidence supporting an acute presentation of bilateral VN as a cause for BVH, which would not have been observed without critical assessment of each of the 10 vestibular end organs.

Combination immunotherapy in the treatment of chronic bilateral panuveitis and uveitic glaucoma during acute dengue fever infection in the Caribbean.

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Stewart, Kevin P; Tawakol, Jan B; Khan, Tasnim; Capriotti, Joseph A

2015-01-01

Ocular manifestations of the dengue fever virus include bilateral panuveitis that can occur after the acute systemic infection has resolved. In most reported cases, the inflammation resolves with topical or systemic steroid therapy. We report a case of chronic, refractory bilateral panuveitis and uveitic glaucoma that began during the acute phase of the systemic infection and required treatment with oral steroids, multiple steroid-sparing agents, and surgical therapy for glaucoma. A 22-year-old male with acute systemic dengue fever presented with bilateral pain and decreased vision. Clinical examination revealed bilateral panuveitis with elevated intraocular pressures. Management required oral steroids, mycophenolate mofetil, cyclosporine, and bilateral glaucoma valve implantation. This case highlights the fact that dengue-associated panuveitis can begin in the acute stage of systemic infection and persist long after convalescence with progression to chronic bilateral panuveitis and uveitic glaucoma. Dengue-associated chronic panuveitis with uveitic glaucoma may be effectively managed with a combination of steroid-sparing oral immunosuppression and glaucoma surgery. This is, to our knowledge, the first case of bilateral refractory dengue-associated panuveitis from the Caribbean treated with combination steroid-sparing oral immunosuppression and bilateral glaucoma valve implantation.

Bilateral acute retinal necrosis-A case report

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Prasad Palimar

1992-01-01

Full Text Available A 42 year old man presented with acute bilateral uveitis and necrotizing retinitis. Systemic investigations including test for AIDS and CMV retinitis were negative. Despite oral Acyclovir, both eyes progressed rapidly to retinal detachment with loss of vision. Early recognition is necessary to diagnose the bilateral acute retinal necrosis syndrome and initiate treatment. Bilateral acute retinal necrosis (BARN is a term first coined by Young and Bird in 1978 although the syndrome had been originally described by Urayama et al as an unilateral condition. This syndrome is characterized by the triad of acute confluent peripheral necrotizing retinitis, moderate to severe vasculitis and vitritis in an otherwise healthy individual. Rhegmatogenous retinal detachment occurs within two to three months of the onset of the disease and the second eye is involved in 36% of patients, usually within 6 weeks. We herein report a patient who presented with simultaneous BARN leading to retinal detachment in a matter of days. Also, to our knowledge this is the first report of this condition in India.

Bilateral Testicular Tumors Resulting in Recurrent Cushing Disease After Bilateral Adrenalectomy.

Science.gov (United States)

Puar, Troy; Engels, Manon; van Herwaarden, Antonius E; Sweep, Fred C G J; Hulsbergen-van de Kaa, Christina; Kamphuis-van Ulzen, Karin; Chortis, Vasileios; Arlt, Wiebke; Stikkelbroeck, Nike; Claahsen-van der Grinten, Hedi L; Hermus, Ad R M M

2017-02-01

Recurrence of hypercortisolism in patients after bilateral adrenalectomy for Cushing disease is extremely rare. We present a 27-year-old man who previously underwent bilateral adrenalectomy for Cushing disease with complete clinical resolution. Cushingoid features recurred 12 years later, with bilateral testicular enlargement. Hormonal tests confirmed adrenocorticotropic hormone (ACTH)-dependent Cushing disease. Surgical resection of the testicular tumors led to clinical and biochemical remission. Gene expression analysis of the tumor tissue by quantitative polymerase chain reaction showed high expression of all key steroidogenic enzymes. Adrenocortical-specific genes were 5.1 × 105 (CYP11B1), 1.8 × 102 (CYP11B2), and 6.3 × 104 (MC2R) times higher than nonsteroidogenic fibroblast control. This correlated with urine steroid metabolome profiling showing 2 fivefold increases in the excretion of the metabolites of 11-deoxycortisol, 21-deoxycortisol, and total glucocorticoids. Leydig-specific genes were 4.3 × 101 (LHCGR) and 9.3 × 100 (HSD17B3) times higher than control, and urinary steroid profiling showed twofold increased excretion of the major androgen metabolites androsterone and etiocholanolone. These distinctly increased steroid metabolites were suppressed by dexamethasone but unresponsive to human chorionic gonadotropin stimulation, supporting the role of ACTH, but not luteinizing hormone, in regulating tumor-specific steroid excess. We report bilateral testicular tumors occurring in a patient with recurrent Cushing disease 12 years after bilateral adrenalectomy. Using mRNA expression analysis and steroid metabolome profiling, the tumors demonstrated both adrenocortical and gonadal steroidogenic properties, similar to testicular adrenal rest tumors found in patients with congenital adrenal hyperplasia, suggesting the presence of pluripotent cells even in patients without congenital adrenal hyperplasia. Copyright © 2017 by the Endocrine Society

Bilateral Bell palsy as a presenting sign of preeclampsia.

Science.gov (United States)

Vogell, Alison; Boelig, Rupsa C; Skora, Joanna; Baxter, Jason K

2014-08-01

Bell palsy is a facial nerve neuropathy that is a rare disorder but occurs at higher frequency in pregnancy. Almost 30% of cases are associated with preeclampsia or gestational hypertension. Bilateral Bell palsy occurs in only 0.3%-2.0% of cases of facial paralysis, has a poorer prognosis for recovery, and may be associated with a systemic disorder. We describe a case of a 24-year-old primigravid woman with a twin gestation at 35 weeks diagnosed initially with bilateral facial palsy and subsequently with preeclampsia. She then developed partial hemolysis, elevated liver enzymes, and low platelet count syndrome, prompting the diagnosis of severe preeclampsia, and was delivered. Bilateral facial palsy is a rare entity in pregnancy that may be the first sign of preeclampsia and suggests increased severity of disease, warranting close monitoring.

Amnesia due to bilateral hippocampal glioblastoma

International Nuclear Information System (INIS)

Shimauchi, M.; Wakisaka, S.; Kinoshita, K.

1989-01-01

The authors report a unique case of glioblastoma which caused permanent amnesia. Magnetic resonance imaging showed the lesion to be limited to the hippocampal formation bilaterally. Although glioblastoma extends frequently into fiber pathways and expands into the opposite cerebral hemisphere, making a 'butterfly' lesion, it is unusual for it to invade the limbic system selectively to this extent. (orig.)

Robotic 4D ultrasound solution for real-time visualization and teleoperation

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Al-Badri Mohammed

2017-09-01

Full Text Available Automation of the image acquisition process via robotic solutions offer a large leap towards resolving ultrasound’s user-dependency. This paper, as part of a larger project aimed to develop a multipurpose 4d-ultrasonic force-sensitive robot for medical applications, focuses on achieving real-time remote visualisation for 4d ultrasound image transfer. This was possible through implementing our software modification on a GE Vivid 7 Dimension workstation, which operates a matrix array probe controlled by a KUKA LBR iiwa 7 7-DOF robotic arm. With the help of robotic positioning and the matrix array probe, fast volumetric imaging of target regions was feasible. By testing ultrasound volumes, which were roughly 880 kB in size, while using gigabit Ethernet connection, a latency of ∼57 ms was achievable for volume transfer between the ultrasound station and a remote client application, which as a result allows a frame count of 17.4 fps. Our modification thus offers for the first time real-time remote visualization, recording and control of 4d ultrasound data, which can be implemented in teleoperation.

Bilateral tension pneumothorax related to acupuncture.

Science.gov (United States)

Tagami, Rumi; Moriya, Takashi; Kinoshita, Kosaku; Tanjoh, Katsuhisa

2013-06-01

We report on a patient with a rare case of bilateral tension pneumothorax that occurred after acupuncture. A 69-year-old large-bodied man, who otherwise had no risk factors for spontaneous pneumothorax, presented with chest pressure, cold sweats and shortness of breath. Immediately after bilateral pneumothorax had been identified on a chest radiograph in the emergency room, his blood pressure and percutaneous oxygen saturation suddenly decreased to 78 mm Hg and 86%, respectively. We confirmed deterioration in his cardiopulmonary status and diagnosed bilateral tension pneumothorax. We punctured his chest bilaterally and inserted chest tubes for drainage. His vital signs promptly recovered. After the bilateral puncture and drainage, we learnt that he had been treated with acupuncture on his upper back. We finally diagnosed a bilateral tension pneumothorax based on the symptoms that appeared 8 h after the acupuncture. Because the patient had no risk factors for spontaneous pneumothorax, no alternative diagnosis was proposed. We recommend that patients receiving acupuncture around the chest wall must be adequately informed of the possibility of complications and expected symptoms, as a definitive diagnosis can be difficult without complete information.

Bilateral, independent juvenile nasopharyngeal angiofibroma: case report.

Science.gov (United States)

Mørkenborg, M-L; Frendø, M; Stavngaard, T; Von Buchwald, C

2015-10-01

Juvenile nasopharyngeal angiofibroma is a benign, vascular tumour that primarily occurs in adolescent males. Despite its benign nature, aggressive growth patterns can cause potential life-threatening complications. Juvenile nasopharyngeal angiofibroma is normally unilateral, originating from the sphenopalatine artery, but bilateral symptoms can occur if a large tumour extends to the contralateral side of the nasopharynx. This paper presents the first reported case of true bilateral extensive juvenile nasopharyngeal angiofibroma involving clinically challenging pre-surgical planning and surgical strategy. A 21-year-old male presented with increasing bilateral nasal obstruction and discharge. Examination revealed tumours bilaterally and imaging demonstrated non-contiguous tumours. Pre-operative angiography showed strictly ipsilateral vascular supplies requiring bilateral embolisation. Radical removal performed as one-step, computer-assisted functional endoscopic sinus surgery was performed. The follow-up period was uncomplicated. This case illustrates the importance of suspecting bilateral juvenile nasopharyngeal angiofibroma in patients presenting with bilateral symptoms. Our management, including successful pre-operative planning, enabled one-step total removal of both tumours and rapid patient recovery.

Bilateral internal laryngoceles mimicking asthma

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Elif A Aksoy

2013-01-01

Full Text Available Laryngocele is an air-filled, abnormal dilation of the laryngeal saccule that extends upward within the false vocal fold, in communication with the laryngeal lumen. A case of 43-year-old male with bilateral internal laryngoceles, who has been treated as asthma for 4 years, is presented. The patient had dyspnea, cough, and excessive phlegm for a month and a late onset stridor. Flexible nasopharyngolaryngoscopy showed bilateral cystic enlargements of the false vocal folds and true vocal folds could not be visualized. Laryngeal CT without contrast enhancement showed bilateral internal laryngoceles. Submucosal total excision of bilateral cystic masses including parts of false vocal folds was performed. The symptoms resolved immediately after surgery. Although the incidence of internal laryngocele is rare, it should be remembered in the differential diagnosis of upper airway problems and diagnostic flexible nasopharnygolaryngoscopy is routinely indicated for airway evaluation in at-risk patients.

Simultaneous and staged bilateral total hip arthroplasty

DEFF Research Database (Denmark)

Lindberg-Larsen, Martin; Joergensen, Christoffer Calov; Husted, Henrik

2013-01-01

Bilateral total hip arthroplasty (BTHA) and bilateral simultaneous total hip arthroplasty (BSTHA) are done increasingly. Previous studies evaluating outcomes after bilateral procedures have found different results. The aim of this study was to investigate length of hospital stay (LOS), 30 days...

Bilateral spontaneous hemotympanum: Case report

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Economou Nicolas C

2006-10-01

Full Text Available Abstract Background The most common causes of hemotympanum are therapeutic nasal packing, epistaxis, blood disorders and blunt trauma to the head. Hemotympanum is characterized as idiopathic, when it is detected in the presence of chronic otitis media. A rare case of spontaneous bilateral hemotympanum in a patient treated with anticoagulants is presented herein. Case presentation A 72-year-old male presented with acute deterioration of hearing. In the patient's medical history aortic valve replacement 1 year before presentation was reported. Since then he had been administered regularly coumarinic anticoagulants, with INR levels maintained between 3.4 and 4.0. Otoscopy revealed the presence of bilateral hemotympanum. The audiogram showed symmetrical moderately severe mixed hearing loss bilaterally, with the conductive component predominating. Tympanograms were flat bilaterally with absent acoustic reflexes. A computerized tomography scan showed the presence of fluid in the mastoid and middle ear bilaterally. Treatment was conservative and consisted of a 10-day course of antibiotics, anticongestants and temporary interruption of the anticoagulant therapy. After 3 weeks, normal tympanic membranes were found and hearing had returned to previous levels. Conclusion Anticoagulant intake should be included in the differential diagnosis of hemotympanum, because its detection and appropriate treatment may lead to resolution of the disorder.

The effect of a robot-assisted surgical system on the kinematics of user movements.

Science.gov (United States)

Nisky, Ilana; Hsieh, Michael H; Okamura, Allison M

2013-01-01

Teleoperated robot-assisted surgery (RAS) offers many advantages over traditional minimally invasive surgery. However, RAS has not yet realized its full potential, and it is not clear how to optimally train surgeons to use these systems. We hypothesize that the dynamics of the master manipulator impact the ability of users to make desired movements with the robot. We compared freehand and teleoperated movements of novices and experienced surgeons. To isolate the effects of dynamics from procedural knowledge, we chose simple movements rather than surgical tasks. We found statistically significant effects of teleoperation and user expertise in several aspects of motion, including target acquisition error, movement speed, and movement smoothness. Such quantitative assessment of human motor performance in RAS can impact the design of surgical robots, their control, and surgeon training methods, and eventually, improve patient outcomes.

Maestro: a tele-robotic system for decommissioning of nuclear plants

International Nuclear Information System (INIS)

Desbats, P.; Idasiak, J.M.

2008-01-01

Compared to electric manipulators, hydraulic manipulators can handle higher payloads with respect to their size and mass. However, due to their limited positioning resolution and dexterity, they are usually disqualified for precise tele-manipulation and high quality tele-operation. More over, experience feedback has shown that on-the-shelf hydraulic manipulators are not reliable when performing high demanding tasks in tele-operation for dismantling applications. In order to solve this problem, CEA (Commissariat l'Energie Atomique), in collaboration with Cybernetix company, has developed a computer-aided, high-precision remote handling system with force-feedback featuring the advanced hydraulic tele-robotic arm Maestro. (authors)

T-Rex system for operation in TRU, LLW, and hazardous zones

International Nuclear Information System (INIS)

Kline, H.M.; Andreychek, T.P.; Beeson, B.K.

1993-01-01

There are a large number of sites around the world containing TRU (transuranic) waste, low level waste (LLW), and hazardous areas that require teleoperated, heavy lift manipulators with long reach and high precision to handle the materials stored there. Teleoperation of the equipment is required to reduce the risk to operating personnel to as-low-as-reasonably-achievable (ALARA) levels. The Transuranic Storage Area Remote Excavator system (T-Rex) is designed to fill this requirement at low cost through the integration of a production front shovel excavator with a control system, local and remote operator control stations, a closed-circuit television system (CCTV), multiple end effectors and a quick-change system. This paper describes the conversion of an off-the-shelf excavator with a hydraulic control system, the integration of an onboard remote control system, vision system, and the design of a remote control station

Silicosis with bilateral spontaneous pneumothorax

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Fotedar Sanjay

2010-01-01

Full Text Available Presentation with simultaneous bilateral pneumothorax is uncommon and usually in the context of secondary spontaneous pneumothorax.The association of pneumothorax and silicosis is infrequent and most cases are unilateral. Bilateral pneumothorax in silicosis is very rare with just a few reports in medical literature.

Bilateral Keratectasia 34 Years after Corneal Transplant

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Xavier Valldeperas

2010-07-01

Full Text Available We report the clinical findings of a patient with severe bilateral keratectasia 34 years after a penetrating keratoplasty (PK in both eyes. An otherwise healthy 67-year-old man complained of deterioration of the eyesight in both eyes over the last 6 months. The patient was diagnosed with bilateral keratoconus at the age of 32 years, and he underwent a bilateral PK. At presentation, visual acuity was 20/200 in the right eye and light perception in the left eye. A Pentacam pachymetric map revealed a central pachymetry of 720 µm in the right eye and of 710 µm in the left eye, as well as an average paracentral pachymetry of 436 and 270 µm in the 9-mm zone in the right and the left eye, respectively. Corneal topography revealed bilateral irregular and asymmetric bowing with generalized steepening and high corneal power. We describe a case of bilateral keratectasia 34 years after PK in a patient who was originally diagnosed with bilateral keratoconus.

Massive Bilateral Serous Retinal Detachment in a Case of Hypertensive Chorioretinopathy

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Luis Villalba-Pinto

2014-07-01

Full Text Available Introduction: Systemic high blood pressure is related to a variety of retinal manifestations. We present an atypical case of hypertensive chorioretinopathy with massive bilateral serous retinal detachment. Case Report: A 26-year-old male with a genitourinary malformation and secondary grade IV chronic kidney failure as well as high blood pressure complained of acute vision loss. Dilated fundus examination evidenced a bilateral serous retinal detachment with macular involvement. The patient was unresponsive to oral antihypertensive therapy and dialysis treatment. The serous retinal detachment progressively decreased after the restoration of dialysis and antihypertensive therapy. The final visual acuity was 0.50 in both eyes. Discussion: In cases of serous macular detachment, it is mandatory to rule out different systemic and ocular diseases. The presence of uncontrolled high blood pressure may produce aggressive bilateral retinal changes, thus hypertension must be under early and strict control in order to improve the visual outcomes.

Massive Bilateral Serous Retinal Detachment in a Case of Hypertensive Chorioretinopathy

Science.gov (United States)

Villalba-Pinto, Luis; Hernández-Ortega, M. Ángeles; de los Mozos, F. Javier Lavid; Pascual-Camps, Isabel; Dolz-Marco, Rosa; Arevalo, J. Fernando; Gallego-Pinazo, Roberto

2014-01-01

Introduction Systemic high blood pressure is related to a variety of retinal manifestations. We present an atypical case of hypertensive chorioretinopathy with massive bilateral serous retinal detachment. Case Report A 26-year-old male with a genitourinary malformation and secondary grade IV chronic kidney failure as well as high blood pressure complained of acute vision loss. Dilated fundus examination evidenced a bilateral serous retinal detachment with macular involvement. The patient was unresponsive to oral antihypertensive therapy and dialysis treatment. The serous retinal detachment progressively decreased after the restoration of dialysis and antihypertensive therapy. The final visual acuity was 0.50 in both eyes. Discussion In cases of serous macular detachment, it is mandatory to rule out different systemic and ocular diseases. The presence of uncontrolled high blood pressure may produce aggressive bilateral retinal changes, thus hypertension must be under early and strict control in order to improve the visual outcomes. PMID:25120474

A boy with bilateral SUNA

DEFF Research Database (Denmark)

Vuković Cvetković, Vlasta; Jensen, Rigmor Højland

2017-01-01

secondary causes should be searched for vigorously if there are bilateral symptoms. Despite a number of therapeutic trials, effective management for the majority of SUNA patients is not available at present. Management of SUNA is often difficult. Case We report the case of a young boy with bilateral SUNA...

Bilateral juvenile nasopharyngeal angiofibroma: report of a case.

Science.gov (United States)

Wu, Edward C; Chark, Davin W; Bhandarkar, Naveen D

2014-07-01

Juvenile nasopharyngeal angiofibroma (JNA) is the most common benign neoplasm of the nasopharynx. Almost always unilateral on diagnosis, JNAs are locally invasive and may extend across the midline, giving a false bilateral appearance; as such, true bilateral JNA is exceedingly rare. We present a recent case of true bilateral JNA. Single case report of a patient with bilateral JNA, including clinical presentation, diagnosis, and management. The patient presented with unilateral nasal obstruction and recurrent epistaxis. Computed tomography and magnetic resonance imaging demonstrated bilateral, noncontiguous masses. Angiography revealed independent vascular supplies from each respective side with no bilateral supply noted. The patient underwent preoperative embolization followed by endoscopic surgical removal of the larger mass; no complications were noted. Follow-up at 2 years demonstrated no recurrence or growth. The vast majority of JNAs are unilateral, though invasive growth to the contralateral side may appear "bilateral" in presentation. Proper identification of true bilateral JNA is helpful in guiding management, wherein excision of both tumors may not be necessary. © 2014 ARS-AAOA, LLC.

Bilateral Acute Angle-Closure Glaucoma Induced By Escitalopram

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Dilbade Yıldız Ekinci

2014-10-01

Full Text Available Escitalopram is an antidepressant of the selective serotonin reuptake inhibitor(SSRI class. In this manuscript, we report the case of a female patient who developed bilateral acute angle-closure glaucoma induced by escitalopram. A 46-year-old female patient was admitted to our ophthalmology clinic with complaints of severe pain around the both eyes, headache, nausea, and vomiting for two days. In her past medical history, she was using escitalopram for depression for two years. Visual acuity was at hand movement level in both eyes. Anterior segment examination showed bilateral diffuse conjunctival hyperemia, corneal edema, shallow anterior chamber, and fixed dilated pupils. Intraocular pressure was 47 mmHg in the right and 68 mmHg in the left eye. The diagnosis was acute angle-closure glaucoma, and the escitalopram medication was discontinued. She was treated with topical and systemic antiglaucomatous medication. After the cornea become clear, bilateral peripheral laser iridotomy was done. In the following year, she did not begin escitalopram medication again and no other acute angle-closure attack was seen. (Turk J Ophthalmol 2014; 44:396-9

Satellite services system overview

Science.gov (United States)

Rysavy, G.

1982-01-01

The benefits of a satellite services system and the basic needs of the Space Transportation System to have improved satellite service capability are identified. Specific required servicing equipment are discussed in terms of their technology development status and their operative functions. Concepts include maneuverable television systems, extravehicular maneuvering unit, orbiter exterior lighting, satellite holding and positioning aid, fluid transfer equipment, end effectors for the remote manipulator system, teleoperator maneuvering system, and hand and power tools.

Bilateral complex regional pain syndrome following spinal cord injury and bilateral calcaneus fracture

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Ahmet Boyacı

2013-09-01

Full Text Available Complex regional pain syndrome (CRPS is a disease affectingone or more extremities, characterized by spontaneouspain, allodynia, hyperpathia and hyperalgesia.CRPS is separated into Type 1 and Type 2. CRPS whichdevelops after a nociceptive event is labeled as Type 1and when it develops following peripheral nerve damage,Type 2. Although the pathogenesis is not fully understood,peripheral and central sensitivity are held responsible.Bilateral lower extremity involvement is extremely rare.However, it should be borne in mind that it can develop intraumatic injuries which occur in more than one area anddiagnosis and commencement of a rehabilitation programshould be made in the early period. The case is presentedhere of bilateral Type 1 CRPS developing after incompletespinal cord injury and bilateral calcaneus fracture. JClin Exp Invest 2013; 4 (3: 360-363Key words: complex regional pain syndrome, calcaneusfracture, spinal cord injury

Bilateral orbital bone infarction in sickle-cell disease.

Science.gov (United States)

Ghafouri, Roya H; Lee, Irene; Freitag, Suzanne K; Pira, Tony N

2011-01-01

This is a case of a 2-year-old boy with sickle cell disease who presented with bilateral eyelid swelling, limited extraocular motility, and lateral subperiosteal fluid collection associated with bilateral lateral orbital wall infarctions on MRI. The patient was managed medically with intravenous fluids, analgesics, broad-spectrum antibiotics, systemic steroids, and clinically improved. Patients with sickle cell disease are susceptible to infarction of the orbital bones during vaso-occlusive crises. Orbital wall infarction can lead to acute proptosis and restricted extraocular motility. Orbital wall infarction should be considered in sickle cell patients with orbital diseases so that appropriate treatment can be instituted promptly to prevent the serious sequelae of orbital compression syndrome.

The development of advanced robotic technology. A study on the tele-existence and intelligent control of a robot system for nuclear power plants

Energy Technology Data Exchange (ETDEWEB)

Chung, Myung Jin; Byun, Jueng Nam; Kim, Jong Hwan; Lee, Ju Jang; Bang, Seok Won; Chu, Gil Hwan; Park, Jong Cheol; Choi, Jong Seok; Yang, Jung Min; Hong, Sun Ki [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of)

1995-07-01

To increase the efficiency of human intelligence it is required to develop an intelligent monitoring and system. In this research, we develop intelligent control methods related with tele-operation, tele-existence, real-time control technique, and intelligent control technique. Those are key techniques in tele-operation, especially for the repair and maintenance of nuclear power plants. The objective of this project is to develop of the tele-existence and intelligent control system for a robot used in the nuclear power plants. (author). 20 refs.

Bilateral vocal fold immobility in a patient with overlap syndrome rheumatoid arthritis/systemic sclerosis.

Science.gov (United States)

Ingegnoli, Francesca; Galbiati, Valentina; Bacciu, Andrea; Zeni, Silvana; Fantini, Flavio

2007-10-01

Bilateral vocal fold immobility (BVFI) can be the result of a primary disorder or as an iatrogenic complication of surgery or intubation. Laryngeal involvement can be a rare complication of connective tissue disorders and it usually occurs in association with other symptoms and signs that indicate active disease. We present a case of BVFI in a patient with an overlap syndrome rheumatoid arthritis/systemic sclerosis, referred to our division because of dysphonia and dyspnea. The video-laryngostroboscopy showed the presence of BVFI. Physical examination, blood tests, lung and neck high resolution computed tomography scans did not demonstrate significant abnormalities. She was treated with pulses of intravenous methylprednisolone with slow improvement.

Parallel control method for a bilateral master-slave manipulator

International Nuclear Information System (INIS)

Miyazaki, Tomohiro; Hagihara, Shiro

1989-01-01

In this paper, a new control method for a bilateral master-slave manipulator is proposed. The proposed method yields stable and fast response of the control system. These are essential to obtain a precise position control and a sensitive force reflection control. In the conventional position-force control method, each control loop of the master and the slave arms are connected in series to construct a bilateral control loop. Therefore the total phase lag through the bilateral control loop becomes twice as much as that of one arm control. Such phase lag makes the control system unstable and control performance worse. To improve the stability and the control performance, we propose 'parallel control method.' In the proposed method, the control loops of the master and the slave arms are connected in parallel so that the total phase lag is reduced to as much as that of one arm. The stability condition of the proposed method is studied and it is proved that the stability of this method can be guaranteed independent of the rigidness of a reaction surface and the position/force ratio between the master and the slave arms while the stability of the conventional method depends on them. (author)

Bilateral acute iris transillumination (BAIT initially misdiagnosed as acute iridocyclitis

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Saban Gonul

2015-04-01

Full Text Available Bilateral acute iris transillumination (BAIT is a relatively new clinical entity characterized by bilateral acute loss of iris pigment epithelium, iris transillumination, pigment dispersion in the anterior chamber, and sphincter paralysis. We report the case of a 30-year-old male who was initially diagnosed with acute iridocyclitis in a different clinic and treated with topical and systemic corticosteroids. He was referred to our clinic to seek another opinion because his symptoms did not improve. An ocular examination revealed bilateral pigment dispersion into the anterior chamber, diffuse iris transillumination, pigment dusting on the anterior lens capsule, atonic and distorted pupils, and increased intraocular pressure, suggesting a diagnosis of BAIT rather than iridocyclitis. Clinicians should be aware of the differential diagnosis of syndromes associated with pigment dispersion from iridocyclitis to avoid aggressive anti-inflammatory therapy and detailed investigation for uveitis.

Bilateral macular hemorrhage due to megaloblastic anemia: A rare case report

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Sree Kumar Vaggu

2016-01-01

Full Text Available We report a case of a 17-year-old female patient who presented with sudden, painless, nonprogressive diminished vision in both eyes (best corrected visual acuity in right eye - 6/60 and left eye - 6/36. An ophthalmological evaluation revealed bilateral pale tarsal conjunctiva and bilateral macular hemorrhage. Hematological evaluation revealed the presence of megalocytic anemia (with hemoglobin - 4.9 g%. General examination showed severe pallor. On systemic examination, no abnormality was detected, confirmed by ultrasonography abdomen. Other causes of severe anemia have been ruled out. Intraocular pressure in both eyes was 12 mmHg. This case documents the rare occurrence of bilateral subinternal limiting membrane macular hemorrhage with megaloblastic anemia without thrombocytopenia and other retinal features of anemic retinopathy.

Bilateral Facial Paralysis Caused by Bilateral Temporal Bone Fracture: A Case Report and a Literature Review

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Sultan Şevik Eliçora

2015-01-01

Full Text Available Bilateral facial paralysis caused by bilateral temporal bone fracture is a rare clinical entity, with seven cases reported in the literature to date. In this paper, we describe a 40-year-old male patient with bilateral facial paralysis and hearing loss that developed after an occupational accident. On physical examination, House-Brackmann (HB facial paralysis of grade 6 was observed on the right side and HB grade 5 paralysis on the left. Upon temporal bone computed tomography (CT examination, a fracture line exhibiting transverse progression was observed in both petrous temporal bones. Our patient underwent transmastoid facial decompression surgery of the right ear. The patient refused a left-side operation. Such patients require extensive monitoring in intensive care units because the presence of multiple injuries means that facial functions are often very difficult to evaluate. Therefore, delays may ensue in both diagnosis and treatment of bilateral facial paralysis.

Immediately sequential bilateral cataract surgery: advantages and disadvantages.

Science.gov (United States)

Singh, Ranjodh; Dohlman, Thomas H; Sun, Grace

2017-01-01

The number of cataract surgeries performed globally will continue to rise to meet the needs of an aging population. This increased demand will require healthcare systems and providers to find new surgical efficiencies while maintaining excellent surgical outcomes. Immediately sequential bilateral cataract surgery (ISBCS) has been proposed as a solution and is increasingly being performed worldwide. The purpose of this review is to discuss the advantages and disadvantages of ISBCS. When appropriate patient selection occurs and guidelines are followed, ISBCS is comparable with delayed sequential bilateral cataract surgery in long-term patient satisfaction, visual acuity and complication rates. In addition, the risk of bilateral postoperative endophthalmitis and concerns of poorer refractive outcomes have not been supported by the literature. ISBCS is cost-effective for the patient, healthcare payors and society, but current reimbursement models in many countries create significant financial barriers for facilities and surgeons. As demand for cataract surgery rises worldwide, ISBCS will become increasingly important as an alternative to delayed sequential bilateral cataract surgery. Advantages include potentially decreased wait times for surgery, patient convenience and cost savings for healthcare payors. Although they are comparable in visual acuity and complication rates, hurdles that prevent wide adoption include liability concerns as ISBCS is not an established standard of care, economic constraints for facilities and surgeons and inability to fine-tune intraocular lens selection in the second eye. Given these considerations, an open discussion regarding the advantages and disadvantages of ISBCS is important for appropriate patient selection.

Bilateral optic neuropathy in acute cryptococcal meningitis

Institute of Scientific and Technical Information of China (English)

Qi Zhe Ngoo; Li Min Evelyn Tai; Wan Hazabbah Wan Hitam; John Tharakan

2016-01-01

We reported a case of cryptococcal meningitis presenting with bilateral optic neuropathy in an immunocompetent patient. A 64-year-old Malay gentleman with no medical comorbidities presented with acute bilateral blurring of vision for a week, which was associated with generalised throbbing headache and low grade fever. He also had som-nolence and altered consciousness. Visual acuity in both eyes was no perception of light with poor pupillary reflexes. Extraocular muscle movements were normal. Anterior segments were unremarkable bilaterally. Fundoscopy revealed bilateral optic disc swelling. CT scan of the brain showed multifocal infarct, but no meningeal enhancement or mass. Cerebrospinal fluid opening pressure was normal, while its culture grew Cryptococcus neoformans. A diagnosis of cryptococcal meningitis with bilateral optic neuropathy was made. Patient was treated with a six-week course of intravenous flu-conazole and started concomitantly on a fortnight's course of intravenous amphotericin B. After that, his general condition improved, but there was still no improvement in his visual acuity. On reviewing at two months post-initiation of treatment, fundi showed bilateral optic atrophy. Bilateral optic neuropathy secondary to cryptococcal meningitis was rare. The prognosis was guarded due to the sequelae of optic atrophy. Anti-fungal medication alone may not be sufficient to manage this condition. However, evidence for other treatment modalities is still lacking and further clinical studies are required.

Pattern of secure bilateral transactions ensuring power economic dispatch in hybrid electricity markets

International Nuclear Information System (INIS)

Kumar, Ashwani; Gao, Wenzhong

2009-01-01

This paper proposes a new method for secure bilateral transactions determination ensuring economic power dispatch of the generators using new AC distribution factors for pool and bilateral coordinated markets. The new optimization problem considers simultaneous minimization of deviations from scheduled transactions and fuel cost of the generators in the network. The fuel cost has been obtained for hybrid market model and impact of different percentage of bilateral demand on fuel cost, generation share, and pattern of transactions has also been determined. The impact of optimally located unified power flow controller (UPFC) on the bilateral transactions, fuel cost and generation pattern has also been studied. The results have also been obtained for pool market model. The proposed technique has been applied on IEEE 24-bus reliability test system (RTS). (author)

Bilateral breast cancer after cured Hodgkin's disease

International Nuclear Information System (INIS)

Anderson, N.; Lokich, J.

1990-01-01

Three patients developed bilateral breast cancer at 10 to 24 years after mantle irradiation for locally or systemically advanced Hodgkin's disease (HD). Four of the six cancers in the three patients were detected only by mammography. Pathologically, five of the cancers were intraductal carcinomas (four with an invasive component) with one being a lobular carcinoma. Five of the six lesions were Stage I pathologically without evidence of axillary nodal involvement. It is recommended that female patients with Hodgkin's disease who have received mantle irradiation as part of the therapy for their Hodgkin's disease and who are observed for 10 or more years after completion of mantle irradiation be considered at risk for the development of breast cancer. Such patients should be monitored appropriately by routine bilateral mammograms to increase the early detection of early stage lesions

Bilateral renal calculi

Science.gov (United States)

Sreenevasan, G

1974-01-01

Bilateral renal calculi were present in 114 (10.7%) of 1,070 cases of proved urinary calculus admitted to the Urological Department of the General Hospital, Kuala Lumpur, during the period November 1968—May 1973. The management of bilateral renal calculi is discussed with reference to the first 100 cases in this series. The introduction of renography has greatly facilitated the decision as to which kidney should be operated on first. The management of patients with and without uraemia is discussed and the use of the modified V and V—Y incisions for the removal of staghorn calculi is described. Complications and results are briefly reviewed. ImagesFig. 1Fig. 4Fig. 6Fig. 7 PMID:4845653

FLOWING BILATERAL FILTER: DEFINITION AND IMPLEMENTATIONS

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Maxime Moreaud

2015-06-01

Full Text Available The bilateral filter plays a key role in image processing applications due to its intuitive parameterization and its high quality filter result, smoothing homogeneous regions while preserving the edges of the objects. Considering the image as a topological relief, seeing pixel intensities as peaks and valleys, we introduce a way to control the tonal weighting coefficients, the flowing bilateral filter, reducing "halo" artifacts typically produced by the regular bilateral filter around a large peak surrounded by two valleys of lower values. In this paper we propose to investigate exact and approximated versions of CPU and parallel GPU (Graphical Processing Unit based implementations of the regular and flowing bilateral filter using the NVidia CUDA API. Fast implementations of these filters are important for the processing of large 3D volumes up to several GB acquired by x-ray or electron tomography.

Hardware Implementation of a Bilateral Subtraction Filter

Science.gov (United States)

Huertas, Andres; Watson, Robert; Villalpando, Carlos; Goldberg, Steven

2009-01-01

A bilateral subtraction filter has been implemented as a hardware module in the form of a field-programmable gate array (FPGA). In general, a bilateral subtraction filter is a key subsystem of a high-quality stereoscopic machine vision system that utilizes images that are large and/or dense. Bilateral subtraction filters have been implemented in software on general-purpose computers, but the processing speeds attainable in this way even on computers containing the fastest processors are insufficient for real-time applications. The present FPGA bilateral subtraction filter is intended to accelerate processing to real-time speed and to be a prototype of a link in a stereoscopic-machine- vision processing chain, now under development, that would process large and/or dense images in real time and would be implemented in an FPGA. In terms that are necessarily oversimplified for the sake of brevity, a bilateral subtraction filter is a smoothing, edge-preserving filter for suppressing low-frequency noise. The filter operation amounts to replacing the value for each pixel with a weighted average of the values of that pixel and the neighboring pixels in a predefined neighborhood or window (e.g., a 9 9 window). The filter weights depend partly on pixel values and partly on the window size. The present FPGA implementation of a bilateral subtraction filter utilizes a 9 9 window. This implementation was designed to take advantage of the ability to do many of the component computations in parallel pipelines to enable processing of image data at the rate at which they are generated. The filter can be considered to be divided into the following parts (see figure): a) An image pixel pipeline with a 9 9- pixel window generator, b) An array of processing elements; c) An adder tree; d) A smoothing-and-delaying unit; and e) A subtraction unit. After each 9 9 window is created, the affected pixel data are fed to the processing elements. Each processing element is fed the pixel value for

The Improvement of Telerobotic System Behavior in Contact with Remote Environment by Extension of an Impedance Controller

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Nedim Osmic

2008-11-01

Full Text Available The teleoperation (telerobotic systems often face two key challenges: the existence of communication delays between the master and slave site as well as the addition of force feedback to improve the user’s sense of presence. The first goal of this paper is that the slave manipulator should track the position of the master manipulator and the second goal is that the environmental force acting on the slave, when it contacts a remote environment, be accurately transmitted to the master. For solving both problems we proposed the symmetric impedance matched teleoperation systems with a wave filter in feedback loop. Simulations results using a single-degree of freedom master/slave system are presented showing the performance of the resulting system.

Achondroplasia Associated with Bilateral Keratoconus

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Ammar M. Al Mahmood

2012-01-01

Full Text Available We report a rare case of bilateral keratoconus in association with achondroplasia. A 26-year-old male, with a known case of achondroplasia, complained of bilateral gradual deterioration in vision for the past few years. Slit lamp biomicroscopy showed bilateral central corneal protrusion and stromal thinning at the apex consistent with keratoconus. a trial of hard contact lens fitting failed to improve VA in the left eye (LE. Right eye (RE improved to 20/25. The patient underwent penetrating keratoplasty (PKP in his LE. Twenty-seven months postoperatively, uncorrected visual acuity (UCVA was 20/30. Ophthalmologists should be aware that patients with achondroplasia who complain of poor vision should be suspected of having keratoconus once other more common conditions are ruled out.

Radiological diagnosis of pulmonary sequestration: review of six cases, including one bilateral

International Nuclear Information System (INIS)

Brito Pacheco, E.M. de; Cazerta, N.M.G.; Marins, J.L.C.; Prando, A.

1989-01-01

Radiological diagnosis of pulmonary sequestration: review of six cases, including one bilateral. Pulmonary sequestration is an uncommon disorder consisting of aberrant pulmonary tissue that has no normal connection with the bronchial tree or with the pulmonary arteries, but is supplied by a systemic artery which usually arises from the aorta. Six cases of pulmonary sequestration are presented and the radiological manifestation of this rare congenital disorder are discussed. These sequestrations were intralobar/unilateral in four patients, extralobar/unilateral in one and extralobar/bilateral in the other patient. Special attention is given to the extremely uncommon bilateral sequestration. To our knowledge only four cases of this form of disease has been described in the literature. (author) [pt

Bilateral Complex Regional Pain Syndrome after Fracture of Bilateral Tibia and Fibula

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Senem Şaş

2017-04-01

Full Text Available Complex regional syndrome type 1 (CRPS-1 is a painful clinical condition. It occurs after a painful event and characterized by allodynia, hyperalgesia, edema, abnormalities in skin blood flow and abnormal sudomotor activity. When CRPS-1 is associated with nerve injury, it is defined as CRPS-2. Central and peripheral theory are responsible in etiopathogenesis of CRPS-1. Generally it occurs in the injured limb. But, it may ocur in the opposite extremities. In this article, we present a case developing bilateral CRPS-1 after bilateral tibia and fibula fracture by reviewing current literatüre.

Bilateral tension pneumothorax after acupuncture.

Science.gov (United States)

Mohammad, Nurashikin

2018-04-19

Acupuncture is an ancient complementary medicine which is currently used worldwide. Many serious adverse events have been reported which include a spectrum of mild-to-fatal complications. However, the level of awareness with regard to complications is still low both to physicians and patients. We report a 63-year-old who presented with acute shortness of breath 2 hours after having had acupuncture. On examination, there was absent breath sound heard on the left lung and slightly reduced breath sound on the right lung. She had type 1 respiratory failure. Urgent chest radiograph confirmed bilateral pneumothorax which was more severe on the left with tension pneumothorax and mediastinal shift. Chest tubes were inserted bilaterally after failed needle aspiration attempts. Subsequently, the pneumothoraces resolved, and she was discharged well. The bilateral pneumothoraces caused by acupuncture were curable but could have been potentially fatal if diagnosis was delayed. This case report adds to the limited current literature on the complications of acupuncture leading to bilateral pneumothoraces. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Tinnitus after Simultaneous and Sequential Bilateral Cochlear Implantation.

Science.gov (United States)

Ramakers, Geerte G J; Kraaijenga, Véronique J C; Smulders, Yvette E; van Zon, Alice; Stegeman, Inge; Stokroos, Robert J; Free, Rolien H; Frijns, Johan H M; Huinck, Wendy J; Van Zanten, Gijsbert A; Grolman, Wilko

2017-01-01

There is an ongoing global discussion on whether or not bilateral cochlear implantation should be standard care for bilateral deafness. Contrary to unilateral cochlear implantation, however, little is known about the effect of bilateral cochlear implantation on tinnitus. To investigate tinnitus outcomes 1 year after bilateral cochlear implantation. Secondarily, to compare tinnitus outcomes between simultaneous and sequential bilateral cochlear implantation and to investigate long-term follow-up (3 years). This study is a secondary analysis as part of a multicenter randomized controlled trial. Thirty-eight postlingually deafened adults were included in the original trial, in which the presence of tinnitus was not an inclusion criterion. All participants received cochlear implants (CIs) because of profound hearing loss. Nineteen participants received bilateral CIs simultaneously and 19 participants received bilateral CIs sequentially with an inter-implant interval of 2 years. The prevalence and severity of tinnitus before and after simultaneous and sequential bilateral cochlear implantation were measured preoperatively and each year after implantation with the Tinnitus Handicap Inventory (THI) and Tinnitus Questionnaire (TQ). The prevalence of preoperative tinnitus was 42% (16/38). One year after bilateral implantation, there was a median difference of -8 (inter-quartile range (IQR): -28 to 4) in THI score and -9 (IQR: -17 to -9) in TQ score in the participants with preoperative tinnitus. Induction of tinnitus occurred in five participants, all in the simultaneous group, in the year after bilateral implantation. Although the preoperative and also the postoperative median THI and TQ scores were higher in the simultaneous group, the median difference scores were equal in both groups. In the simultaneous group, tinnitus scores fluctuated in the 3 years after implantation. In the sequential group, four patients had an additional benefit of the second CI: a total

Bilateral pallidotomy for generalized dystonia Palidotomia bilateral para distonias generalizadas

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Hélio A. G. Teive

2001-06-01

Full Text Available OBJECTIVE: To evaluate the efficacy and safety of bilateral pallidotomies in five patients with generalized dystonia. BACKGROUND: Generalized dystonias are frequently a therapeutic challenge, with poor responses to pharmacological treatment. GPi (globus pallidus internus pallidotomies for Parkinson's disease ameliorate all kinds of dyskinesias/dystonia, and recent studies reported a marked improvement of refractory dystonias with this procedure. METHODS: Five patients with generalized dystonias refractory to medical treatment were selected; one posttraumatic and four idiopathic. The decision to perform bilateral procedures was based on the predominant axial involvement in these patients. Dystonia severity was assessed with the Burke-Fahn-Marsden Dystonia Scale (BFM. Simultaneous procedures were performed in all but one patient, who had a staged procedure. They were reevaluated with the same scale (BFM by an unblinded rater at 1, 2, 3, 30, 60, 90, 120 and 180 days post-operatively. RESULTS: The four patients with idiopathic dystonia showed a progressive improvement up to three months; the patient with posttraumatic dystonia relapsed at three months. One patient had a marked improvement, being able to discontinue all the medications. A mean decrease in the BFM scores of 52,58% was noted. One patient had a trans-operative motor seizure followed by a transient hemiparesis secondary to rack hemorrhage; other was lethargic up to three days after the procedure. CONCLUSIONS: Our results show that bilateral GPi pallidotomies may be a safe and effective approach to medically refractory generalized dystonias; it can also be speculated that the posttraumatic subgroup may not benefit with this procedure.As distonias generalizadas são freqüentemente um desafio terapêutico, com pobres respostas aos tratamentos farmacológicos. As cirurgias estereotáxicas, como a palidotomia, têm sido utilizadas com êxito no tratamento da doença de Parkinson e estudos

Simultaneous bilateral elbow dislocation with bilateral medial epicondyle fractures in a 13-year-old female gymnast with hyperlaxity

Science.gov (United States)

Bauer, Stefan; Dunne, Ben; Whitewood, Colin

2012-01-01

Bilateral simultaneous elbow dislocations are extremely rare and have only been described in 12 cases. In the paediatric population unilateral elbow dislocations are rare with 3–6% of all elbow injuries and there are only few studies describing this injury exclusively in children. There is only one case report of a paediatric patient who sustained a simultaneous bilateral elbow dislocation with medial epicondyle fractures. We present a second paediatric case of simultaneous bilateral elbow dislocation with associated displaced bilateral medial epicondyle fractures in a gymnast with joint hyperlaxity (3 of 5 Wynne-Davies criteria) treated with closed reduction and short-term immobilisation (3 weeks). The patient returned to full trampoline gymnastics between 4 and 5 months postinjury and made an uneventful recovery. PMID:23234820

A case of bilateral tubal pregnancy

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Ayano Funamizu

2017-11-01

Full Text Available Bilateral tubal pregnancy is very rare and occurs in only 1 out of every 200,000 spontaneous pregnancies. In this case, a 29-year-old woman with a history of primary infertility underwent treatment with human menopausal gonadotropin (hMG-human chorionic gonadotropin (hCG, and became pregnant. A gestational sac (GS was not detected in the uterus and transvaginal ultrasonography (USG revealed GS with fetal heartbeat in the left adnexa at 7 weeks and 6 days of gestation. The patient underwent laparoscopic surgery and ultimately, bilateral tubal pregnancy was diagnosed. Consequently, bilateral fallopian tube resection was performed. Afterwards, she conceived by assisted reproductive technology (ART and delivered vaginally. This case suggests that even if a GS is found in one fallopian tube by USG, it is important to evaluate the other fallopian tube carefully. Keywords: bilateral tubal pregnancy, ectopic pregnancy, human menopausal gonadotropin, laparoscopy

Bilateral sarkoidose i glandula parotis

DEFF Research Database (Denmark)

Hahn, Pernille; Krogdahl, Annelise; Godballe, Christian

2012-01-01

We describe an unusual case of sarcoidosis in which the patient presented with a bilateral swelling of the parotid salivary glands and no other manifestation of the disease. Sarcoidosis is a multisystem granulomatous disorder of unknown cause in which there may be multiple exocrine involvement......, including the salivary glands. This case emphasises the importance of including sarcoidosis in the differential diagnosis of bilateral parotid swelling....

MODERN VIEWS ON BILATERAL BREAST CANCER

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Ye. A. Fesik

2014-01-01

Full Text Available Presented modern literature data on the features of the pathogenesis, course, clinical and morphological expression and tumor characteristics, parameters and nodal metastasis of hematogenous bilateral breast cancer. Highlight the results of domestic and foreign studies in recent years to determine the prognostic factors and recurrence of synchronous and metachronous bilateral breast cancer. It was revealed that the frequency of bilateral breast tumor lesions varies widely, ranging from 0.1 to 20%, with metachronous tumors recorded significantly higher (69.6% than the synchronous (22.7%. The probability of occurrence of metachronous breast cancer is higher in women with a family history, as well as if they have a gene mutation BRCA-1. Found that the most common histological type of breast tumor with bilateral lesions is invasive ductal. However, the incidence of invasive lobular cancer and non-invasive lobular cancer is slightly higher among synchronous bilateral cancer compared with unilateral disease. Studies have shown that in a double-sided synchronous breast cancer tumor, as a rule, has a lower degree of differentiation, and the higher the expression level of estrogen receptors and progesterone receptors. Relevance of the issue because the identification of patterns in the study of lymphatic and hematogenous features bilateral metastasis of mammary tumors provides a basis for speculation about the differences in the progression of neoplastic disease in these groups and is a cause for further detailed research in this area to identify and evaluate the prognosis and also the choice of tactics of such patients.

Paresia diafragmática bilateral idiopática Idiopathic bilateral diaphragmatic paresis

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Mônica Corso Pereira

2006-10-01

Full Text Available Relata-se o caso de um paciente com dispnéia intensa ao se deitar, em que foram excluídas doenças pulmonares, neuromusculares ou cardíacas, cuja investigação revelou paresia diafragmática bilateral. Um sinal chave para o diagnóstico foi a evidência de respiração paradoxal com o doente em decúbito supino. Havia piora da oxigenação e da capacidade vital forçada com a mudança da posição ortostática para supina. A fluoroscopia ortostática foi normal. A pressão inspiratória máxima estava muito reduzida. A estimulação elétrica transcutânea do diafragma foi normal, e a eletroestimulação do nervo frênico mostrou ausência de resposta, permitindo o diagnóstico de paresia bilateral do diafragma.We report the case of a patient with severe dyspnea upon reclining. Lung disease, neuromuscular disorders and heart disease were ruled out. However, during the course of the investigation, bilateral diaphragmatic paresis was discovered. A key sign leading to the diagnosis was evidence of paradoxical respiration in the dorsal decubitus position. When the patient was moved from the orthostatic position to the dorsal decubitus position, oxygenation and forced vital capacity worsened. The orthostatic fluoroscopy was normal. Maximal inspiratory pressure was severely reduced. The responses to transcutaneous electric stimulation of the diaphragm were normal. However, electric stimulation of the phrenic nerve produced no response, leading to the diagnosis of bilateral diaphragmatic paresis.

Bilateral microperc in a severe kyphoscoliosis

OpenAIRE

Dağgülli, Mansur; Penbegül, Necmettin; Dede, Onur; Utanğaç, Mehmet Mazhar

2016-01-01

Percutaneous nephrolithotomy is the standard modality for large renal calculi in normal and abnormal renal anatomic situations. This case report describes a 57-year-old male patient who presented with bilateral kidney stones and severe kyphoscoliosis. He had successfully been treated with a bilateral microperc technique.

A case of bilateral trench foot.

Science.gov (United States)

Parsons, S L; Leach, I H; Charnley, R M

1993-12-01

A case of severe bilateral trench foot is presented in a patient who lived rough for 3 weeks without removing his boots. Non-operative management yielded no clinical improvement and bilateral below-knee amputation was necessary. Histology revealed subcutaneous and muscle necrosis with secondary arterial thrombosis.

Surgical tactic of high bilateral abdominal testicular retention in patient with a prune belly syndrome

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I. A. Panchenko

2014-11-01

Full Text Available Bilateral abdominal cryptorchism in combination with other defects of urogenital system and a prune belly syndrome keep within a syndrome of connective tissue dysplasia. In our medical center developed the method of surgical correction of a high bilateral abdominal testicular retention with preservation of vessels.

Surgical tactic of high bilateral abdominal testicular retention in patient with a prune belly syndrome

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I. A. Panchenko

2013-01-01

Full Text Available Bilateral abdominal cryptorchism in combination with other defects of urogenital system and a prune belly syndrome keep within a syndrome of connective tissue dysplasia. In our medical center developed the method of surgical correction of a high bilateral abdominal testicular retention with preservation of vessels.

A rare case of bilateral aspergillus endophthalmitis

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Saurabh Gupta

2015-12-01

Full Text Available Aspergillus endophthalmitis is a devastating inflammatory condition of the intraocular cavities that may result in irreparable loss of vision and rapid destruction of the eye. Almost all cases in the literature have shown an identified source causing aspergillus endophthalmitis as a result of direct extension of disease. We present a rare case of bilateral aspergillus endophthalmitis. A 72-year-old woman with a history of diabetes mellitus, congenital Hirschsprung disease, and recent culture-positive candida pyelonephritis with hydronephrosis status post-surgical stent placement presented with difficulty opening her eyes. She complained of decreased vision (20/200 with pain and redness in both eyes – right worse then left. Examination demonstrated multiple white fungal balls in both retinas consistent with bilateral fungal endophthalmitis. Bilateral vitreous taps for cultures and staining were performed. Patient was given intravitreal injections of amphotericin B, vancomycin, ceftazidime, and started on oral fluconazole. Patient was scheduled for vitrectomy to decrease organism burden and to remove loculated areas of infection that would not respond to systemic antifungal agents. Four weeks after initial presentation, the fungal cultures revealed mold growth consistent with aspergillus. Patient was subsequently started on voriconazole and fluconazole was discontinued due to poor efficacy against aspergillus. Further workup was conducted to evaluate for the source of infection and seeding. Transthoracic cardiogram was unremarkable for any vegetation or valvular abnormalities. MRI of the orbits and sinuses did not reveal any mass lesions or bony destruction. CT of the chest was unremarkable for infection. Aspergillus endophthalmitis may occur because of one of these several mechanisms: hematogenous dissemination, direct inoculation by trauma, and contamination during surgery. Our patient's cause of bilateral endophthalmitis was through an

On the use of exchange rates as trading rules in a bilateral system of transferable discharge permits

International Nuclear Information System (INIS)

Rodriguez, F.

2000-01-01

The use of a system of transferable discharge permits to control the harmful effects of non-uniformly mixed pollutants requires the application of trading rules in order to prevent permit trading among sources from violating environmental standards. The elements and properties of bilateral trading rules can be analyzed more easily once formulated as exchange rates, which would convert, in a cost-effective way, the emission right potentially given up by the seller into an offsetting emission right acquired by the buyer. In this article, a new expression for such exchange rates is proposed and then analyzed to infer some unexplored properties of the system. 8 refs

Ceratite bilateral por Acanthamoeba: relato de caso Bilateral Acanthamoeba keratitis: case report

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Wilson Nahmatallah Obeid

2003-12-01

Full Text Available A ceratite por Acanthamoeba é uma infecção ocular grave que, apesar dos recentes progressos no diagnóstico e tratamento, ainda provoca prolongada morbidade e perda da acuidade visual. Relatamos um caso de ceratite bilateral por Acanthamoeba em usuário de lentes de contato, que é o primeiro caso descrito na literatura brasileira.Acanthamoeba keratitis is a severe ocular infection which even with recent progress in diagnosis and treatment still causes long morbidity and loss of visual acuity. We describe a case of bilateral Acanthamoeba keratitis in a user of contact lenses, which is the first case discussed in Brazilian literature.

Characteristics of vertigo and the affected vestibular nerve systems in idiopathic bilateral vestibulopathy.

Science.gov (United States)

Fujimoto, Chisato; Kinoshita, Makoto; Kamogashira, Teru; Egami, Naoya; Sugasawa, Keiko; Yamasoba, Tatsuya; Iwasaki, Shinichi

2016-01-01

Vertigo attacks in IBV patients involving both the superior and inferior vestibular nerve systems were significantly more severe than vertigo attacks in patients with selective involvement of the inferior vestibular nerve system alone. To investigate the relationship between the frequency and duration of vertigo and the affected vestibular nerve system in idiopathic bilateral vestibulopathy (IBV). This study categorized 44 IBV patients into the following three sub-groups according to the affected vestibular nerve system: superior, inferior, and mixed type. These patients were also categorized into the following three sub-groups according to their clinical time course: progressive type showing no episodes of vertigo, sequential type showing recurrent vertigo attacks and single-attack type showing a single episode of vertigo. Ten, 11 and 23 patients were classified as the superior, the inferior, and the mixed type, respectively. Seventeen, 23, and four patients were classified as the progressive, the sequential, and the single-attack type, respectively. For the patients having one or more vertigo attacks, the duration of the vertigo attack was longer than 24 h in 69% of the mixed type, and the duration of vertigo in the mixed type was significantly longer than that in the inferior type (p < 0.05).

Successful treatment of multiple bilateral impactions - a case report.

Science.gov (United States)

Schubert, Michael; Proff, Peter; Kirschneck, Christian

2016-07-25

Successful treatment of patients with multiple bilateral impactions can be an orthodontic challenge, but few reports on treatment planning and execution exist. In this case report, we describe the successful orthodontic treatment of a 16.3-year old female patient without systemic or genetic disease with initially nine persisting deciduous and nine impacted permanent teeth with complete root formation and closed apices in both jaws. After extraction of the deciduous and surgical exposure of the impacted permanent teeth, the Easy-Way-Coil™ system was used in conjunction with a skeletal anchorage (maxilla, BENEfit™ system) to guide the eruption of all impacted teeth. After a total treatment time of only 22.8 months all impacted teeth could be aligned successfully and a stable and functional class I occlusion was achieved. In addition, there were no adverse treatment effects such as anchorage loss, root resorptions or periodontal problems and an esthetic result could be achieved. The presented treatment approach thus proved to be highly effective in cases with multiple bilateral impactions with minimal side effects and considerably reduced treatment time.

Tinnitus after Simultaneous and Sequential Bilateral Cochlear Implantation

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Geerte G. J. Ramakers

2017-11-01

Full Text Available ImportanceThere is an ongoing global discussion on whether or not bilateral cochlear implantation should be standard care for bilateral deafness. Contrary to unilateral cochlear implantation, however, little is known about the effect of bilateral cochlear implantation on tinnitus.ObjectiveTo investigate tinnitus outcomes 1 year after bilateral cochlear implantation. Secondarily, to compare tinnitus outcomes between simultaneous and sequential bilateral cochlear implantation and to investigate long-term follow-up (3 years.Study designThis study is a secondary analysis as part of a multicenter randomized controlled trial.MethodsThirty-eight postlingually deafened adults were included in the original trial, in which the presence of tinnitus was not an inclusion criterion. All participants received cochlear implants (CIs because of profound hearing loss. Nineteen participants received bilateral CIs simultaneously and 19 participants received bilateral CIs sequentially with an inter-implant interval of 2 years. The prevalence and severity of tinnitus before and after simultaneous and sequential bilateral cochlear implantation were measured preoperatively and each year after implantation with the Tinnitus Handicap Inventory (THI and Tinnitus Questionnaire (TQ.ResultsThe prevalence of preoperative tinnitus was 42% (16/38. One year after bilateral implantation, there was a median difference of −8 (inter-quartile range (IQR: −28 to 4 in THI score and −9 (IQR: −17 to −9 in TQ score in the participants with preoperative tinnitus. Induction of tinnitus occurred in five participants, all in the simultaneous group, in the year after bilateral implantation. Although the preoperative and also the postoperative median THI and TQ scores were higher in the simultaneous group, the median difference scores were equal in both groups. In the simultaneous group, tinnitus scores fluctuated in the 3 years after implantation. In the sequential group

A RARE CASE OF BILATERAL MICROSPHEREPHAKIA

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Pandu

2015-05-01

Full Text Available Microspherophakia is rare bilateral congenital anamoly of the crystalline lens. The condition may be isolated , familial or it may be associated with systemic affections like Marfan's syndrome , Weil - Marchesani syndrome , hyperlysinemia and congenital rubella. Microspherophakia results in lenticular myopia , lens dislocation , usually inferiorly and inverse glaucoma. We present a case in a 8 year old child who presented with bilateral microspherophakia and anterior dislocation of lens of right eye. visual acuity in right eye was counting fingers close to face and i n left eye 6/60.IOP with perkins applanation tonometer was 30mmHg in right eye 22mmHg in left eye , cornea was hazy due to edema , anterior chamber was shallow in both eye patient was managed with emergency lens extraction of right eye and secondary ACIOL im plantation. Left eye was managed by laser peripheral iridotomy. IOP was within normal limits postoperatively in both eyes without any antiglaucoma medications. Postoperatively best corrected visual acuity in right was 6/18 and 6/9 in left eye.

Bilateral agenesis of the anterior cruciate ligament: MRI evaluation

Energy Technology Data Exchange (ETDEWEB)

Bedoya, Maria A.; Jaramillo, Diego [The Children' s Hospital of Philadelphia, Radiology Department, Philadelphia, PA (United States); McGraw, Michael H. [Hospitalof theUniversityof Pennsylvania, Divisionof Orthopaedics, Philadelphia, PA (United States); Wells, Lawrence [The Children' s Hospital of Philadelphia, Division of Orthopaedics, Philadelphia, PA (United States)

2014-09-15

Bilateral agenesis of the anterior cruciate ligament (ACL) is extremely rare. We describe a 13-year-old girl who presented with bilateral knee pain without history of trauma; she has two family members with knee instability. Magnetic resonance imaging showed bilateral absence of the ACL, and medial posterior horn meniscal tears. Bilateral arthroscopic partial meniscectomy and anterior cruciate ligament reconstruction was performed. (orig.)

Staged bilateral carotid endarterectomy

DEFF Research Database (Denmark)

Schroeder, T; Sillesen, H; Engell, Hans Christian

1986-01-01

In a series of 56 staged bilateral carotid endarterectomies, new neurologic symptoms developed in 5% and 20% following the first and second procedure, respectively. All complications were transient or minor. The incidence of postendarterectomy hypertension was significantly higher following...... the second procedure, when operations were staged less than 3 weeks apart. A correlation between these hypertensive episodes and the occurrence of new neurologic symptoms could not be shown. However, as this correlation has been proved in several other reports, bilateral carotid endarterectomy is advised...... to be staged at least 3 weeks apart. In addition, a conservative attitude towards contralateral asymptomatic lesions is proposed....

Reinnervation of bilateral posterior cricoarytenoid muscles using the left phrenic nerve in patients with bilateral vocal fold paralysis.

Directory of Open Access Journals (Sweden)

Meng Li

Full Text Available OBJECTIVE: To evaluate the feasibility, effectiveness, and safety of reinnervation of the bilateral posterior cricoarytenoid (PCA muscles using the left phrenic nerve in patients with bilateral vocal fold paralysis. METHODS: Forty-four patients with bilateral vocal fold paralysis who underwent reinnervation of the bilateral PCA muscles using the left phrenic nerve were enrolled in this study. Videostroboscopy, perceptual evaluation, acoustic analysis, maximum phonation time, pulmonary function testing, and laryngeal electromyography were performed preoperatively and postoperatively. Patients were followed-up for at least 1 year after surgery. RESULTS: Videostroboscopy showed that within 1 year after reinnervation, abductive movement could be observed in the left vocal folds of 87% of patients and the right vocal folds of 72% of patients. Abductive excursion on the left side was significantly larger than that on the right side (P 0.05. No patients developed immediate dyspnea after surgery, and the pulmonary function parameters recovered to normal reference value levels within 1 year. Postoperative laryngeal electromyography confirmed successful reinnervation of the bilateral PCA muscles. Eighty-seven percent of patients in this series were decannulated and did not show obvious dyspnea after physical activity. Those who were decannulated after subsequent arytenoidectomy were not included in calculating the success rate of decannulation. CONCLUSIONS: Reinnervation of the bilateral PCA muscles using the left phrenic nerve can restore inspiratory vocal fold abduction to a physiologically satisfactory extent while preserving phonatory function at the preoperative level without evident morbidity.

Reinnervation of Bilateral Posterior Cricoarytenoid Muscles Using the Left Phrenic Nerve in Patients with Bilateral Vocal Fold Paralysis

Science.gov (United States)

Zheng, Hongliang; Chen, Donghui; Zhu, Minhui; Wang, Wei; Liu, Fei; Zhang, Caiyun

2013-01-01

Objective To evaluate the feasibility, effectiveness, and safety of reinnervation of the bilateral posterior cricoarytenoid (PCA) muscles using the left phrenic nerve in patients with bilateral vocal fold paralysis. Methods Forty-four patients with bilateral vocal fold paralysis who underwent reinnervation of the bilateral PCA muscles using the left phrenic nerve were enrolled in this study. Videostroboscopy, perceptual evaluation, acoustic analysis, maximum phonation time, pulmonary function testing, and laryngeal electromyography were performed preoperatively and postoperatively. Patients were followed-up for at least 1 year after surgery. Results Videostroboscopy showed that within 1 year after reinnervation, abductive movement could be observed in the left vocal folds of 87% of patients and the right vocal folds of 72% of patients. Abductive excursion on the left side was significantly larger than that on the right side (P 0.05). No patients developed immediate dyspnea after surgery, and the pulmonary function parameters recovered to normal reference value levels within 1 year. Postoperative laryngeal electromyography confirmed successful reinnervation of the bilateral PCA muscles. Eighty-seven percent of patients in this series were decannulated and did not show obvious dyspnea after physical activity. Those who were decannulated after subsequent arytenoidectomy were not included in calculating the success rate of decannulation. Conclusions Reinnervation of the bilateral PCA muscles using the left phrenic nerve can restore inspiratory vocal fold abduction to a physiologically satisfactory extent while preserving phonatory function at the preoperative level without evident morbidity. PMID:24098581

MRI features of bilateral parotid haemangiomas of infancy

International Nuclear Information System (INIS)

Andronikou, Savvas; Jadwat, Saaleeha; McHugh, Kieran; Linward, Jane

2003-01-01

The aim of this article is to report the MRI features of bilateral parotid haemangiomas of infancy and highlight the diagnostic and prognostic value of MRI especially with regard to those lesions that may cause respiratory compromise. Retrospective review of MRI scans in six infants with bilateral parotid haemangiomas. The bilateral haemangiomas were symmetrical in all but one patient. On T1-weighted images the masses were isointense to muscle and on T2 they were hyperintense with numerous small vessels giving a septated appearance. There was vivid enhancement with gadolinium in all cases. In three patients, deep bilateral extensions were demonstrated involving the parapharyngeal spaces resulting in respiratory compromise which required tracheostomy. Bilateral parotid haemangiomas are rare, but when present may have deep extensions, which can result in respiratory compromise requiring tracheostomy. (orig.)

MRI features of bilateral parotid haemangiomas of infancy

Energy Technology Data Exchange (ETDEWEB)

Andronikou, Savvas; Jadwat, Saaleeha [Institute of Child Health, University of Cape Town, Klipfontein Road, Rondebosch, 7700, Cape Town (South Africa); McHugh, Kieran; Linward, Jane [Department of Radiology, Great Ormond Street Hospital for Children, London, WC1N 3JH (United Kingdom)

2003-04-01

The aim of this article is to report the MRI features of bilateral parotid haemangiomas of infancy and highlight the diagnostic and prognostic value of MRI especially with regard to those lesions that may cause respiratory compromise. Retrospective review of MRI scans in six infants with bilateral parotid haemangiomas. The bilateral haemangiomas were symmetrical in all but one patient. On T1-weighted images the masses were isointense to muscle and on T2 they were hyperintense with numerous small vessels giving a septated appearance. There was vivid enhancement with gadolinium in all cases. In three patients, deep bilateral extensions were demonstrated involving the parapharyngeal spaces resulting in respiratory compromise which required tracheostomy. Bilateral parotid haemangiomas are rare, but when present may have deep extensions, which can result in respiratory compromise requiring tracheostomy. (orig.)

Bilateral electric energy contracts: return and risk

Energy Technology Data Exchange (ETDEWEB)

Gunn, Laura K.; Silva, Elisa B.; Correia, Paulo B. [State University of Campinas (UNICAMP), SP (Brazil). College of Mechanical Engineering

2009-07-01

In Brazil electricity is traded through three segments: the spot market that balances offer and demand, with prices calculated by a cost-based computational model; the regulated market , where prices are settled in public auctions, and the free market for bilateral contracts. As spot and regulated market prices are public information, a seller is able to calculate his opportunity price to trade a bilateral contract in the free market by using the non-arbitrage principle. Thus, the seller searches the price of a bilateral contract in the free market that balances his/her revenues with the value expected in case it were negotiated in the regulated and the spot market. Besides the expected revenue, the seller may also consider the CVaR to measure the risk of her/his bilateral contract in the free market. So this paper develops a binomial lattice approach to price bilateral contracts in the free market, considering the seller's opportunity of negotiations in both regulated and spot markets, and measuring the contract risk directly. (author)

Robot-assisted ultrasound imaging: overview and development of a parallel telerobotic system.

Science.gov (United States)

Monfaredi, Reza; Wilson, Emmanuel; Azizi Koutenaei, Bamshad; Labrecque, Brendan; Leroy, Kristen; Goldie, James; Louis, Eric; Swerdlow, Daniel; Cleary, Kevin

2015-02-01

Ultrasound imaging is frequently used in medicine. The quality of ultrasound images is often dependent on the skill of the sonographer. Several researchers have proposed robotic systems to aid in ultrasound image acquisition. In this paper we first provide a short overview of robot-assisted ultrasound imaging (US). We categorize robot-assisted US imaging systems into three approaches: autonomous US imaging, teleoperated US imaging, and human-robot cooperation. For each approach several systems are introduced and briefly discussed. We then describe a compact six degree of freedom parallel mechanism telerobotic system for ultrasound imaging developed by our research team. The long-term goal of this work is to enable remote ultrasound scanning through teleoperation. This parallel mechanism allows for both translation and rotation of an ultrasound probe mounted on the top plate along with force control. Our experimental results confirmed good mechanical system performance with a positioning error of < 1 mm. Phantom experiments by a radiologist showed promising results with good image quality.

Robotic dismantlement systems at the CP-5 reactor D and D project

International Nuclear Information System (INIS)

Seifert, L. S.

1998-01-01

The Chicago Pile 5 (CP-5) Research Reactor Facility is currently undergoing decontamination and decommissioning (D and D) at the Argonne National Laboratory (ANL) Illinois site. CP-5 was the principle nuclear reactor used to produce neutrons for scientific research at Argonne from 1954 to 1979. The CP-5 reactor was a heavy-water cooled and moderated, enriched uranium-fueled reactor with a graphite reflector. The CP-5 D and D project includes the disassembly, segmentation and removal of all the radioactive components, equipment and structures associated with the CP-5 facility. The Department of Energy's Robotics Technology Development Program and the Federal Energy Technology Center, Morgantown Office provided teleoperated, remote systems for use in the dismantlement of the CP-5 reactor assembly for tasks requiring remote dismantlement as part of the EM-50 Large-Scale Demonstration Program (LSDP). The teleoperated systems provided were the Dual Arm Work Platform (DAWP), the Rosie Mobile Teleoperated Robot Work System (ROSIE), and a remotely-operated crane control system with installed swing-reduction control system. Another remotely operated apparatus, a Brokk BM250, was loaned to ANL by the Princeton Plasma Physics Laboratory (PPPL). This machine is not teleoperated and was not part of the LSDP, but deserves some mention in this discussion. The DAWP is a robotic dismantlement system that includes a pair of Schilling Robotic Systems Titan III hydraulic manipulator arms mounted to a specially designed support platform: a hydraulic power unit (HPU) and a remote operator console. The DAWP is designed to be crane-suspended for remote positioning. ROSIE, developed by RedZone Robotics, Inc. is a mobile, electro-hydraulic, omnidirectional platform with a heavy-duty telescoping boom mounted to the platform's deck. The work system includes the mobile platform (locomotor), a power distribution unit (PDU) and a remote operator console. ROSIE moves about the reactor building

Bilateral Traumatic Globe Luxation with Optic Nerve Transection

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Levent Tok

2014-12-01

Full Text Available Purpose: The purpose of this study was to document clinical findings and management of a patient with bilateral globe luxation and optic nerve transection. Materials and Methods: A 25-year-old female patient was admitted to the emergency department with bilateral traumatic globe luxation following a motor vehicle accident. Results: Visual acuity testing showed no light perception. The right pupil was dilated and bilaterally did not react to light. The globes were bilaterally intact. A computed tomography scan revealed Le Fort type II fractures, bilateral optic nerve transection and disruption of all extraocular muscles. The globes of the patient were bilaterally reduced into the orbit. However, the patient developed phthisis bulbi in the right eye at month 3. Conclusion: Globe luxation presents a dramatic clinical picture, and may lead to the development of severe complications due to the concomitance of complete optic nerve dissection and multiple traumas. Even if the luxated globe is repositioned into the orbit, there is still an increased risk of the development of phthisis due to ischemia.

Bilateral Traumatic Globe Luxation with Optic Nerve Transection

Science.gov (United States)

Tok, Levent; Tok, Ozlem Yalcin; Argun, Tugba Cakmak; Yilmaz, Omer; Gunes, Alime; Unlu, Elif Nisa; Sezer, Sezgin; Ibisoglu, Seda; Argun, Mehmet

2014-01-01

Purpose The purpose of this study was to document clinical findings and management of a patient with bilateral globe luxation and optic nerve transection. Materials and Methods A 25-year-old female patient was admitted to the emergency department with bilateral traumatic globe luxation following a motor vehicle accident. Results Visual acuity testing showed no light perception. The right pupil was dilated and bilaterally did not react to light. The globes were bilaterally intact. A computed tomography scan revealed Le Fort type II fractures, bilateral optic nerve transection and disruption of all extraocular muscles. The globes of the patient were bilaterally reduced into the orbit. However, the patient developed phthisis bulbi in the right eye at month 3. Conclusion Globe luxation presents a dramatic clinical picture, and may lead to the development of severe complications due to the concomitance of complete optic nerve dissection and multiple traumas. Even if the luxated globe is repositioned into the orbit, there is still an increased risk of the development of phthisis due to ischemia. PMID:25606034

Bilateral varicoceles as an indicator of underlying portal-hypertension

African Journals Online (AJOL)

A. Adam

2016-08-01

Aug 1, 2016 ... compression from the conglomerate of collateral veins (Fig. 2). Our index patient defaulted from follow up, further investigations and refused further treatment. Discussion. Patients with underlying portal hypertension and a porto-systemic shunt rarely present with a right-sided or bilateral varicocele. A.

Bilateral adrenal masses: a single-centre experience

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Nilesh Lomte

2016-05-01

Full Text Available Background Bilateral adrenal masses may have aetiologies like hyperplasia and infiltrative lesions, besides tumours. Hyperplastic and infiltrative lesions may have coexisting hypocortisolism. Bilateral tumours are likely to have hereditary/syndromic associations. The data on clinical profile of bilateral adrenal masses are limited. Aims To analyse clinical, biochemical and radiological features, and management outcomes in patients with bilateral adrenal masses. Methods Retrospective analysis of 70 patients with bilateral adrenal masses presenting to a single tertiary care endocrine centre from western India (2002–2015. Results The most common aetiology was pheochromocytoma (40%, followed by tuberculosis (27.1%, primary adrenal lymphoma (PAL (10%, metastases (5.7%, non-functioning adenomas (4.3%, primary bilateral macronodular adrenal hyperplasia (4.3%, and others (8.6%. Age at presentation was less in patients with pheochromocytoma (33 years and tuberculosis (41 years compared with PAL (48 years and metastases (61 years (P<0.001. The presenting symptoms for pheochromocytoma were hyperadrenergic spells (54% and abdominal pain (29%, whereas tuberculosis presented with adrenal insufficiency (AI (95%. The presenting symptoms for PAL were AI (57% and abdominal pain (43%, whereas all cases of metastasis had abdominal pain. Mean size of adrenal masses was the largest in lymphoma (5.5cm followed by pheochromocytoma (4.8cm, metastasis (4cm and tuberculosis (2.1cm (P<0.001. Biochemically, most patients with pheochromocytoma (92.8% had catecholamine excess. Hypocortisolism was common in tuberculosis (100% and PAL (71.4% and absent with metastases (P<0.001. Conclusion In evaluation of bilateral adrenal masses, age at presentation, presenting symptoms, lesion size, and biochemical features are helpful in delineating varied underlying aetiologies.

Bilateral adrenal masses: a single-centre experience

Science.gov (United States)

Bandgar, Tushar; Khare, Shruti; Jadhav, Swati; Lila, Anurag; Goroshi, Manjunath; Kasaliwal, Rajeev; Khadilkar, Kranti; Shah, Nalini S

2016-01-01

Background Bilateral adrenal masses may have aetiologies like hyperplasia and infiltrative lesions, besides tumours. Hyperplastic and infiltrative lesions may have coexisting hypocortisolism. Bilateral tumours are likely to have hereditary/syndromic associations. The data on clinical profile of bilateral adrenal masses are limited. Aims To analyse clinical, biochemical and radiological features, and management outcomes in patients with bilateral adrenal masses. Methods Retrospective analysis of 70 patients with bilateral adrenal masses presenting to a single tertiary care endocrine centre from western India (2002–2015). Results The most common aetiology was pheochromocytoma (40%), followed by tuberculosis (27.1%), primary adrenal lymphoma (PAL) (10%), metastases (5.7%), non-functioning adenomas (4.3%), primary bilateral macronodular adrenal hyperplasia (4.3%), and others (8.6%). Age at presentation was less in patients with pheochromocytoma (33 years) and tuberculosis (41 years) compared with PAL (48 years) and metastases (61 years) (P<0.001). The presenting symptoms for pheochromocytoma were hyperadrenergic spells (54%) and abdominal pain (29%), whereas tuberculosis presented with adrenal insufficiency (AI) (95%). The presenting symptoms for PAL were AI (57%) and abdominal pain (43%), whereas all cases of metastasis had abdominal pain. Mean size of adrenal masses was the largest in lymphoma (5.5cm) followed by pheochromocytoma (4.8cm), metastasis (4cm) and tuberculosis (2.1cm) (P<0.001). Biochemically, most patients with pheochromocytoma (92.8%) had catecholamine excess. Hypocortisolism was common in tuberculosis (100%) and PAL (71.4%) and absent with metastases (P<0.001). Conclusion In evaluation of bilateral adrenal masses, age at presentation, presenting symptoms, lesion size, and biochemical features are helpful in delineating varied underlying aetiologies. PMID:27037294

Bilateral Ovarian Fibrothecoma Associated with Ascites, Bilateral Pleural Effusion, and Marked Elevated Serum CA-125

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Védi André Serges Loué

2013-01-01

Full Text Available Background. The risk of ovarian cancer is increased in the association of ovarian tumor, ascites, and hydrothorax with the significant elevated tumor marker CA-125. However, this association can be observed in a rare clinical and benign pathological entity, that is Demons-Meigs’ syndrome. Objective. To describe a rare case of Demons-Meigs' syndrome observed in our department. Methods. A black African woman of 35 years old, seventh gravida and fourth parous, underwent a total abdominal hysterectomy with bilateral salpingoophorectomy for large bilateral ovarian masses associated with significant ascites, bilateral pleural effusion, and particular highly elevated tumor marker CA-125 (1835 UI/mL in a pronounced general alteration condition. Results. The postoperative course was uneventful characterized by a complete remission of hydrothorax and ascites with normal level of CA-125 three months after tumor excision. Histology of both masses revealed a bilateral ovarian fibrothecoma, a benign tumor of the ovary, thus confirming the diagnosis of Demons-Meigs’ syndrome. Conclusion. The Demons-Meigs syndrome, although it strongly mimics the clinical picture of malignant metastatic ovarian cancer, remains a disease with benign prognosis after surgical tumor resection. This is a rare condition that must be known and recognized by practitioners to avoid unnecessary practices.

A teleoperated system for remote site characterization

International Nuclear Information System (INIS)

Sandness, G.A.; Richardson, B.S.; Pence, J.

1993-08-01

The detection and characterization of buried objects and materials is an important first step in the restoration of burial sites containing chemical and radioactive waste materials at Department of Energy (DOE) and Department of Defense (DOD) facilities. To address the need to minimize the exposure of on-site personnel to the hazards associated with such sites, the DOE Office of Technology Development and the US Army Environmental Center have jointly supported the development of the Remote Characterization System (RCS). One of the main components of the RCS is a small remotely driven survey vehicle that can transport various combinations of geophysical and radiological sensors. Currently implemented sensors include ground-penetrating radar, magnetometers, an electromagnetic induction sensor, and a sodium iodide radiation detector. The survey vehicle was constructed predominantly of non-metallic materials to minimize its effect on the operation of its geophysical sensors. The system operator controls the vehicle from a remote, truck-mounted, base station. Video images are transmitted to the base station by an radio link to give the operator necessary visual information. Vehicle control commands, tracking information, and sensor data are transmitted between the survey vehicle and the base station by means of a radio ethernet link. Precise vehicle tracking coordinates are provided by a differential Global Positioning System (GPS). The sensors are environmentally protected, internally cooled, and interchangeable based on mission requirements. To date, the RCS has been successfully tested at the Oak Ridge National Laboratory and the Idaho National Engineering Laboratory

Bilateral Tubal Pregnancy without Known Risk Factor

Directory of Open Access Journals (Sweden)

Hyacinthe Zamané

2017-01-01

Full Text Available Spontaneous bilateral ectopic gestation is very rare. The authors report a case diagnosed and taken care of at Yalgado Ouedraogo Teaching Hospital, Ouagadougou. It was a 30-year-old patient with no known pathological history. She had presented at the obstetric emergencies with a state of hypovolemic shock by haemoperitoneum with digestive disorders, pelvic pain, vaginal bleeding, and a mention of delayed menstruation. The ultrasound coupled with the urinary immunological pregnancy test confirmed the diagnosis of ruptured ectopic pregnancy and a bilateral form was suspected. A laparotomy in emergency confirmed the diagnosis of bilateral ectopic gestation with a right ampullary unruptured pregnancy and a left isthmic ruptured gestation. A bilateral salpingectomy was performed and counseling was made for the use of medical help of procreation in case of future need of pregnancy.

[Bilateral torticollis].

Science.gov (United States)

Kustos, T; Magdics, M

1993-12-19

Bilateral torticollis is a very rare form of a well known deformity i.e. muscular torticollis. This malformation might present a differential diagnostic problem both for orthopaedic surgeons and ophthalmologists, as well as, for neurologists. In agreement with the literature, the role of an injury during labour or defective embriogenesis is suggested to play a part.

Bilateral optic neuropathy in acute cr yptococcal meningitis

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Qi Zhe Ngoo

2016-11-01

Full Text Available We reported a case of cryptococcal meningitis presenting with bilateral optic neuropathy in an immunocompetent patient. A 64-year-old Malay gentleman with no medical comorbidities presented with acute bilateral blurring of vision for a week, which was associated with generalised throbbing headache and low grade fever. He also had somnolence and altered consciousness. Visual acuity in both eyes was no perception of light with poor pupillary reflexes. Extraocular muscle movements were normal. Anterior segments were unremarkable bilaterally. Fundoscopy revealed bilateral optic disc swelling. CT scan of the brain showed multifocal infarct, but no meningeal enhancement or mass. Cerebrospinal fluid opening pressure was normal, while its culture grew Cryptococcus neoformans. A diagnosis of cryptococcal meningitis with bilateral optic neuropathy was made. Patient was treated with a six-week course of intravenous fluconazole and started concomitantly on a fortnight's course of intravenous amphotericin B. After that, his general condition improved, but there was still no improvement in his visual acuity. On reviewing at two months post-initiation of treatment, fundi showed bilateral optic atrophy. Bilateral optic neuropathy secondary to cryptococcal meningitis was rare. The prognosis was guarded due to the sequelae of optic atrophy. Anti-fungal medication alone may not be sufficient to manage this condition. However, evidence for other treatment modalities is still lacking and further clinical studies are required.

Neglected simultaneous bilateral femoral neck fractures secondary to narcotic drug abuse treated by bilateral one-staged hemiarthroplasty: a case report

Directory of Open Access Journals (Sweden)

Vahedi Ehsan

2010-06-01

Full Text Available Abstract Simultaneous bilateral femoral neck fractures are extremely rare and associated with various conditions. Up to now Most cases had correlations with major trauma, repetitive minor trauma, seizure, parathyroid or renal dysfunction, anti-epileptic medications, seizure, etc. A 28-year-old addict man referred to us with a 10-year history of narcotic drug abuse and history of 8 months bilateral groin pain. He admitted with displaced bilateral femoral neck fracture. Because of long duration of this condition and osteonecrosis revealed on bone scan, one-staged bilateral hip hemiarthroplasty was done. A good function was noted after surgery to 4-month follow up. Up to now, have not be founded in the literature that a case of bilateral femoral neck fracture associated with narcotic drug abuse. Because of negative effects of opium or smoking on bone tissues, a simple bone pain should aware us about the risk of stress or fatigue fracture.

Simultaneous Bilateral Transient Osteoporosis of the Hip without Pregnancy

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Yasuaki Okada

2016-01-01

Full Text Available Transient osteoporosis of the hip (TOH is a rare disorder characterized by acute severe coxalgia and temporary osteopenia in the proximal femur. Although most cases were unilateral or staged bilateral TOH, some authors reported that the pregnant patients simultaneously had TOH in their bilateral hips. However, there has been no report of simultaneous bilateral TOH in the patient without pregnancy. A 25-year-old Japanese woman without pregnancy had acute simultaneous bilateral hip pain. Plain X-ray of the bilateral hips did not show a periarticular osteopenia. However, magnetic resonance image obtained one week after the onset demonstrated increased T2-weighted signal intensity and decreased T1-weighted signal intensity in the bilateral femoral heads. She was treated conservatively, and follow-up magnetic resonance image at seven weeks after the onset returned to normal bone marrow signal intensity. Her bilateral coxalgia subsided gradually. At one year after the onset, she had no sign of symptomatic flair. Our experience with this case indicates that recognizing the possibility of simultaneous bilateral TOH is important unless the patient is pregnant, and magnetic resonance image is predictable test to make a diagnosis of TOH, even in the absence of abnormal finding on plain X-ray.

Robot technology

International Nuclear Information System (INIS)

Vertut, Jean; Coiffet, Philippe.

1985-01-01

Teleoperation is concerned with the exploration and exploitation of of spaces which do not allow, because of their inaccessibility or hostility, direct access to man. This volume (Parts 2, 3 and 4) covers the contribution of computer science and automatic control to this technology. Part 2 includes a description of teleoperation systems followed by chapters on the operator substitution function by computer feedback to the operator. Part 3 has chapters on performance evaluation of teleoperation systems and the human operator in the teleoperation system. Part 4 is about applications of teleoperation in the nuclear industry, underwater, in space, in medicine, in industry and in security and civil protection. The nuclear applications include research and pilot facilities, reactor operation and maintenance, reactor decommissioning and dismantling and in emergencies, for example following a reactor accident. (U.K.)

Effect of acute bilateral adrenalectomy and reserpine on gastric ...

African Journals Online (AJOL)

STORAGESEVER

2008-09-03

Sep 3, 2008 ... the secretion of gastric mucus in a system where glycoprotein erosion is measured together with adherent mucus secretion in the gastric mucosa in the unstimu- lated state. Therefore, the present study was undertaken to examine the effect of acute bilateral adrenalectomy and dopamine depletory agent ...

Bilateral Wilms' tumor

International Nuclear Information System (INIS)

Malcolm, A.W.; Jaffe, N.; Folkman, M.J.; Cassady, J.R.

1980-01-01

Twenty children with bilateral Wilms' tumor were presented to the Children's Hospital Medical Center and Children's Cancer Research Foundation, Sidney Farber Cancer Institute, and Joint Center for Radiation Therapy (CHMC-CCRF, SFCI, JCRT) from January 1, 1956 to December 31, 1976. Of these 20, 16 had simultaneous and 4 had metachronous disease on presentation. All patients were treated with surgery, radiation and chemotherapy. Of the 16 patients with simultaneous disease, 10 (63%) are alive and free of disease 12+ to 175+ months post diagnosis and treatment, with median follow-up of 121 months. There were no long-term survivors in the metachronous group; all were dead of disease within 21 months from initial presentation of original tumor. With these data we relate prognosis to extent of disease and discuss a general approach to the management of bilateral Wilms' tumor

Maxillary arch width in unoperated adult bilateral cleft lip and alveolus and complete bilateral cleft lip and palate.

NARCIS (Netherlands)

Latief, B.S.; Lekkas, C.; Kuijpers, M.A.R.

2010-01-01

OBJECTIVES: To study maxillary arch width in adult patients with bilateral cleft lip and alveolus (BCLA) or with complete bilateral cleft lip and palate (BCLP), who have not had any surgery. SETTING AND SAMPLING POPULATION: Eighteen patients with BCLA, 13 patients with BCLP, and 24 controls from

Amnesia due to bilateral hippocampal glioblastoma. MRI finding

Energy Technology Data Exchange (ETDEWEB)

Shimauchi, M.; Wakisaka, S.; Kinoshita, K. (Miyazaki Medical Coll., Kiyotake (Japan). Dept. of Neurosurgery)

1989-11-01

The authors report a unique case of glioblastoma which caused permanent amnesia. Magnetic resonance imaging showed the lesion to be limited to the hippocampal formation bilaterally. Although glioblastoma extends frequently into fiber pathways and expands into the opposite cerebral hemisphere, making a 'butterfly' lesion, it is unusual for it to invade the limbic system selectively to this extent. (orig.).

Bilateral ovarian tumour in a young girl | Govindarajan | African ...

African Journals Online (AJOL)

Bilateral ovarian tumour in a girl presents the dilemma of conservative versus aggressive approach towards these tumours. When faced with suspicious tumour and complete replacement of the ovaries bilaterally, bilateral oophorectomy is a viable option, though the certain possibility of infertility and lifelong hormonal ...

Remote handling facility and equipment used for space truss assembly

International Nuclear Information System (INIS)

Burgess, T.W.

1987-01-01

The ACCESS truss remote handling experiments were performed at Oak Ridge National Laboratory's (ORNL's) Remote Operation and Maintenance Demonstration (ROMD) facility. The ROMD facility has been developed by the US Department of Energy's (DOE's) Consolidated Fuel Reprocessing Program to develop and demonstrate remote maintenance techniques for advanced nuclear fuel reprocessing equipment and other programs of national interest. The facility is a large-volume, high-bay area that encloses a complete, technologically advanced remote maintenance system that first began operation in FY 1982. The maintenance system consists of a full complement of teleoperated manipulators, manipulator transport systems, and overhead hoists that provide the capability of performing a large variety of remote handling tasks. This system has been used to demonstrate remote manipulation techniques for the DOE, the Power Reactor and Nuclear Fuel Development Corporation (PNC) of Japan, and the US Navy in addition to the National Aeronautics and Space Administration. ACCESS truss remote assembly was performed in the ROMD facility using the Central Research Laboratory's (CRL) model M-2 servomanipulator. The model M-2 is a dual-arm, bilateral force-reflecting, master/slave servomanipulator which was jointly developed by CRL and ORNL and represents the state of the art in teleoperated manipulators commercially available in the United States today. The model M-2 servomanipulator incorporates a distributed, microprocessor-based digital control system and was the first successful implementation of an entirely digitally controlled servomanipulator. The system has been in operation since FY 1983. 3 refs., 2 figs

Bilateral elastofibroma dorsi: A case report

OpenAIRE

Molini, L.; Ciortan, E.; Bianchi, S.

2010-01-01

Elastofibroma dorsi is a rare pseudotumoral lesion located in the periscapular region. Ultrasound can be used to evaluate its dimensions, margins, and internal structure. In the presence of bilateralism, diagnosis can be made on the basis of clinical and sonographic findings. The authors present a case of bilateral elastofibroma dorsi in which the clinical and ultrasound diagnosis was confirmed by magnetic resonance imaging.

Unusual Presentation of Recurrent Pyogenic Bilateral Psoas Abscess Causing Bilateral Pulmonary Embolism by Iliac Vein Compression

OpenAIRE

Ijaz, Mohsin; Sakam, Sailaja; Ashraf, Umair; Marquez, Jose Gomez

2015-01-01

Patient: Male, 47 Final Diagnosis: Bilateral psoas abscess • acute lower extremity deep vein thrombosis • bilateral pulmonary embolism Symptoms: Progressive left leg swelling • productive cough with whitish sputum • right flank pain Medication: Antibiotics and anticoagulation Clinical Procedure: CT-guided percutaneous drain placement Specialty: Internal Medicine/Critical Care Objective: Unusual presentation Background: Psoas abscesses are a known cause of back pain, but they have not been rep...

Design, Modelling and Teleoperation of a 2 mm Diameter Compliant Instrument for the da Vinci Platform.

Science.gov (United States)

Francis, P; Eastwood, K W; Bodani, V; Looi, T; Drake, J M

2018-05-07

This work explores the feasibility of creating and accurately controlling an instrument for robotic surgery with a 2 mm diameter and a three degree-of-freedom (DoF) wrist which is compatible with the da Vinci platform. The instrument's wrist is composed of a two DoF bending notched-nitinol tube pattern, for which a kinematic model has been developed. A base mechanism for controlling the wrist is designed for integration with the da Vinci Research Kit. A basic teleoperation task is successfully performed using two of the miniature instruments. The performance and accuracy of the instrument suggest that creating and accurately controlling a 2 mm diameter instrument is feasible and the design and modelling proposed in this work provide a basis for future miniature instrument development.

Psychosis in primary angiitis of the central nervous system involving bilateral thalami: a case report.

Science.gov (United States)

Kim, Sangha; Kim, Doh Kwan

2015-01-01

To report a case of primary angiitis of the central nervous system (PACNS), a rare inflammatory disease restricted to the central nervous system (CNS), with unusual clinical presentation mimicking schizophrenia. Case report. A 45-year-old male presented with alteration of consciousness and confusion. Brain magnetic resonance imaging (MRI) scan showed a mass-like enhancing lesion involving bilateral thalami, and biopsy revealed findings compatible with PACNS. The patient was treated with corticosteroids. Psychotic symptoms crystallized over the initial 2 months after the diagnosis and persisted for over a year. Severity of his symptoms improved with gradual normalization of the radiologic findings and antipsychotic medication. Our case highlights the importance of considering PACNS as a differential diagnosis of a tumor-like mass lesion in the CNS and the significance of thalamic involvement in the pathogenesis of psychotic symptoms including delusions and hallucinations. Copyright © 2015. Published by Elsevier Inc.

Similarity in Bilateral Isolated Internal Orbital Fractures.

Science.gov (United States)

Chen, Hung-Chang; Cox, Jacob T; Sanyal, Abanti; Mahoney, Nicholas R

2018-04-13

In evaluating patients sustaining bilateral isolated internal orbital fractures, the authors have observed both similar fracture locations and also similar expansion of orbital volumes. In this study, we aim to investigate if there is a propensity for the 2 orbits to fracture in symmetrically similar patterns when sustaining similar trauma. A retrospective chart review was performed studying all cases at our institution of bilateral isolated internal orbital fractures involving the medial wall and/or the floor at the time of presentation. The similarity of the bilateral fracture locations was evaluated using the Fisher's exact test. The bilateral expanded orbital volumes were analyzed using the Wilcoxon signed-rank test to assess for orbital volume similarity. Twenty-four patients with bilateral internal orbital fractures were analyzed for fracture location similarity. Seventeen patients (70.8%) had 100% concordance in the orbital subregion fractured, and the association between the right and the left orbital fracture subregion locations was statistically significant (P < 0.0001). Fifteen patients were analyzed for orbital volume similarity. The average orbital cavity volume was 31.2 ± 3.8 cm on the right and 32.0 ± 3.7 cm on the left. There was a statistically significant difference between right and left orbital cavity volumes (P = 0.0026). The data from this study suggest that an individual who suffers isolated bilateral internal orbital fractures has a statistically significant similarity in the location of their orbital fractures. However, there does not appear to be statistically significant similarity in the expansion of the orbital volumes in these patients.

Medical tourism: a review of the literature and analysis of a role for bi-lateral trade.

Science.gov (United States)

Smith, Richard; Martínez Álvarez, Melisa; Chanda, Rupa

2011-12-01

With increasing globalization, many countries are considering opening their health systems to greater cross-border movement of patients. This is usually done from the viewpoint of a multi-lateral trade relationship. This paper considers the issues that arise from this debate from a bi-lateral perspective. A systematic literature review was carried out on 'Medical Tourism' from the perspective of a bi-lateral trade relationship, using the UK and India as a case study. There is a dearth of data and discussion on such bi-lateral trade. This limited evidence offers some suggestions. Exporting countries may benefit from medical tourism by generating foreign exchange and reversing the brain drain, but run the risk of creating a dual system, where the local population is crowded out. Importing countries can benefit from alleviating waiting lists and lowering healthcare costs, but may risk quality of care and legal liability. However, evidence from a bi-lateral perspective suggests that the positive aspects can be capitalised, and the negative ones reduced. The key recommendations from this paper are for more evidence to be collected at the country and international level, and for countries to consider trade in health services from a bi-lateral rather than multi-lateral perspective. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Bilateral Intracavernous Carotid Artery Aneurysms Presenting as Diplopia in a Young Patient

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Nikolaos Kopsachilis

2013-01-01

Full Text Available Introduction. Bilateral intracavernous carotid artery aneurysms (ICAAs are extremely rare and difficult to treat. Case Report. A 26-year-old female presented in our clinic with acute diplopia due to oculomotor nerve palsy on the left side. Magnetic resonance imaging of the brain showed two heterogeneously enhanced masses indicating bilateral ICAA. An endovascular coil embolization was performed on the left side successfully, resulting in resolution of her symptoms. Conclusion. Thorough systemic evaluation in young patients with diplopia can reveal life-threatening underlying pathology and prevent major complications.

Bilateral locked facets in the thoracic spine

NARCIS (Netherlands)

M.H.A. Willems; Braakman, R. (Reinder); B. van Linge (Bert)

1984-01-01

textabstractTwo cases of traumatic bilateral locked facets in the thoracic spine are reported. Both patients had only minor neurological signs. They both made a full neurological recovery after surgical reduction of the locked facets. Bilateral locked facets are very uncommon in the thoracic spine.

Fibromuscular Dysplasia Presenting with Bilateral Renal Infarction

International Nuclear Information System (INIS)

Doody, O.; Adam, W. R.; Foley, P. T.; Lyon, S. M.

2009-01-01

Fibromuscular dysplasia (FMD) describes a group of conditions which cause nonatheromatous arterial stenoses, most commonly of the renal and carotid arteries, typically in young women. We report a rare case of bilateral segmental renal infarction secondary to FMD in a young male patient. His initial presentation with loin pain and pyrexia resulted in a delay in the definitive diagnosis of FMD. He was successfully treated with bilateral balloon angioplasty. The delayed diagnosis in this patient until the condition had progressed to bilateral renal infarcts highlights the need for prompt investigation and diagnosis of suspected cases of FMD.

Recurrent Bilateral Breast Abscesses after Sternotomy

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Hamza Cinar

2012-01-01

Full Text Available Median sternotomy is the most commonly used incision in cardiothoracic procedures. Development of breast abscess after sternotomy is a very rare situation. We present a case of sternal wound infection with recurrent bilateral breast abscess after sternotomy. Our case is the first and only case in the literature due to the presence of sternal wound infection with recurrent bilateral breast abscess after sternotomy.

Bilateral agreements

International Nuclear Information System (INIS)

Anon.

2004-01-01

The bilateral agreements concern Brazil with United States relative to the co operation in nuclear energy, Germany with Russian Federation relative to the elimination and disposal of nuclear weapons; The multilateral agreements concerns the signature of the Protocols to amend the Paris and Brussels Conventions, the multilateral nuclear environmental programme in the Russian Federation, the status of Conventions in the field of nuclear energy. (N.C.)

Bilateral Simultaneous Macular Infarction with Spontaneous Visual ...

African Journals Online (AJOL)

To report the rare and dramatic event of bilateral macular infarction in a sickle cell hemoglobinopathy (SS genotype) patient, resulting in bilateral severe reduction in visual acuity. Without any intervention, the patient's vision gradually improved over the follow‑up period. Central visual field defects however persisted.

Noise reduction with complex bilateral filter.

Science.gov (United States)

Matsumoto, Mitsuharu

2017-12-01

This study introduces a noise reduction technique that uses a complex bilateral filter. A bilateral filter is a nonlinear filter originally developed for images that can reduce noise while preserving edge information. It is an attractive filter and has been used in many applications in image processing. When it is applied to an acoustical signal, small-amplitude noise is reduced while the speech signal is preserved. However, a bilateral filter cannot handle noise with relatively large amplitudes owing to its innate characteristics. In this study, the noisy signal is transformed into the time-frequency domain and the filter is improved to handle complex spectra. The high-amplitude noise is reduced in the time-frequency domain via the proposed filter. The features and the potential of the proposed filter are also confirmed through experiments.

Prognosis of synchronous bilateral breast cancer

DEFF Research Database (Denmark)

Holm, Marianne; Tjønneland, Anne; Balslev, Eva

2014-01-01

Currently, no consistent evidence-based guidelines for the management of synchronous bilateral breast cancer (SBBC) exist and it is uncertain how presenting with SBBC affects patients' prognosis. We conducted a review of studies analyzing the association between SBBC and prognosis. The studies...... that reported adjusted effect measures were included in meta-analyses of effect of bilaterality on breast cancer mortality. From 57 initially identified records 17 studies from 11 different countries including 8,050 SBBC patients were included. The quality of the studies varied but was generally low with small...... sample sizes, and lack of consistent, detailed histo-pathological information. When doing meta-analysis on the subgroup of studies that provided adjusted effect estimates on breast cancer mortality (nine studies including 3,631 SBBC cases), we found that bilaterality in itself had a negative impact...

Funding analysis of bilateral autologous free-flap breast reconstructions in Australia.

Science.gov (United States)

Sinha, Shiba; Ruskin, Olivia; McCombe, David; Morrison, Wayne; Webb, Angela

2015-08-01

Bilateral breast reconstructions are being increasingly performed. Autologous free-flap reconstructions represent the gold standard for post-mastectomy breast reconstruction but are resource intensive. This study aims to investigate the difference between hospital reimbursement and true cost of bilateral autologous free-flap reconstructions. Retrospective analysis of patients who underwent bilateral autologous free-flap reconstructions at a single Australian tertiary referral centre was performed. Hospital reimbursement was determined from coding analysis. A true cost analysis was also performed. Comparisons were made considering the effect of timing, indication and complications of the procedure. Forty-six bilateral autologous free-flap procedures were performed (87 deep inferior epigastric perforators (DIEPs), four superficial inferior epigastric artery perforator flaps (SIEAs) and one muscle-sparing free transverse rectus abdominis myocutaneous flap (MS-TRAM)). The mean funding discrepancy between hospital reimbursement and actual cost was $12,137 ± $8539 (mean ± standard deviation (SD)) (n = 46). Twenty-four per cent (n = 11) of the cases had been coded inaccurately. If these cases were excluded from analysis, the mean funding discrepancy per case was $9168 ± $7453 (n = 35). Minor and major complications significantly increased the true cost and funding discrepancy (p = 0.02). Bilateral free-flap breast reconstructions performed in Australian public hospitals result in a funding discrepancy. Failure to be economically viable threatens the provision of this procedure in the public system. Plastic surgeons and hospital managers need to adopt measures in order to make these gold-standard procedures cost neutral. Copyright © 2015 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

Bilateral Medial Medullary Infarction with Nondominant Vertebral Artery Occlusion.

Science.gov (United States)

Zhang, Lei; Zhang, Gui-lian; Du, Ju-mei; Ma, Zhu-lin

2015-09-01

Bilateral medial medullary infarction (MMI) is a rare stroke subtype. Here, we report a case with bilateral MMI caused by nondominant vertebral artery occlusion confirmed by brain digital subtraction angiography and magnetic resonance imaging basi-parallel-anatomical-scanning. We highlight that anterior spinal arteries could originate from a unilateral vertebral artery (VA). Radiologists and neurologists should pay attention to the nondominant VA as bilateral MMI may be induced by occlusion of nondominant VA that supplies the bilateral anteromedial territories of the medulla. Copyright © 2015 National Stroke Association. Published by Elsevier Inc. All rights reserved.

EXERTIONAL RHABDOMYOLYSIS OF THE BILATERAL ADDUCTOR MAGNUS

Directory of Open Access Journals (Sweden)

Tolga Saka

2007-12-01

Full Text Available We present a case study of a person (63 year-old man, who has been using statins for 18 years, with rhabdomyolysis of the bilateral adductor muscles associated with strenuous and prolonged eccentric exercises (hiking in a hot environment. Clinical examination showed predominantly on the right side muscle swelling and palpational pain of the bilateral adductor muscle groups and bilateral tibial edema. His serum creatine kinase (CK level was 12218 IU/L. T2-weighted magnetic resonance (MR images showed a high signal intensity in the bilateral adductor muscles of the hip. The patient did not develop complications and returned to his previous performance level in 30 days following adequate hydration and resting of the affected muscles. Strenuous eccentric exercise should be avoided during the course of statin use and clinicians should be aware of present observations when considering the significance of acute CK elevations in patients on statin treatment

Bilateral nasolabial cysts associated with recurrent dacryocystitis.

Science.gov (United States)

Kyrmizakis, Dionysios E; Lachanas, Vassilios A; Benakis, Antonios A; Velegrakis, George A; Aslanides, Ioannis M

2005-05-01

Nasolabial cysts are rare, nonodontogenic, soft-tissue, developmental cysts occurring inferior to the nasal alar region. They are thought to arise from remnants of the nasolacrimal ducts and they are frequently asymptomatic. We report a rare case of bilateral nasolabial cysts accompanied by bilateral chronic dacryocystitis. A 48-year-old woman suffering from bilateral chronic dacryocystitis was referred to our department for endonasal dacryocystorhinostomy. She had undergone external dacryocystorhinostomy on the left side a few years earlier. Physical examination and computed tomography scan revealed nasolabial cysts bilaterally inferior to the nasal alar region. The cysts were removed via a sublabial approach and endoscopic dacryocystorhinostomy was performed on the right side. Ten months after surgery, the patient was asymptomatic. There may be a correlation, due to embryological reasons, between the presence of nasolabial cysts and the presence of chronic dacryocystitis. Both can be corrected surgically, under the same anaesthesia, without visible scar formation.

Medical telerobotic systems: current status and future trends.

Science.gov (United States)

Avgousti, Sotiris; Christoforou, Eftychios G; Panayides, Andreas S; Voskarides, Sotos; Novales, Cyril; Nouaille, Laurence; Pattichis, Constantinos S; Vieyres, Pierre

2016-08-12

Teleoperated medical robotic systems allow procedures such as surgeries, treatments, and diagnoses to be conducted across short or long distances while utilizing wired and/or wireless communication networks. This study presents a systematic review of the relevant literature between the years 2004 and 2015, focusing on medical teleoperated robotic systems which have witnessed tremendous growth over the examined period. A thorough insight of telerobotics systems discussing design concepts, enabling technologies (namely robotic manipulation, telecommunications, and vision systems), and potential applications in clinical practice is provided, while existing limitations and future trends are also highlighted. A representative paradigm of the short-distance case is the da Vinci Surgical System which is described in order to highlight relevant issues. The long-distance telerobotics concept is exemplified through a case study on diagnostic ultrasound scanning. Moreover, the present review provides a classification into short- and long-distance telerobotic systems, depending on the distance from which they are operated. Telerobotic systems are further categorized with respect to their application field. For the reviewed systems are also examined their engineering characteristics and the employed robotics technology. The current status of the field, its significance, the potential, as well as the challenges that lie ahead are thoroughly discussed.

Force-velocity properties' contribution to bilateral deficit during ballistic push-off.

Science.gov (United States)

Samozino, Pierre; Rejc, Enrico; di Prampero, Pietro Enrico; Belli, Alain; Morin, Jean-Benoît

2014-01-01

The objective of this study is to quantify the contribution of the force-velocity (F-v) properties to bilateral force deficit (BLD) in ballistic lower limb push-off and to relate it to individual F-v mechanical properties of the lower limbs. The F-v relation was individually assessed from mechanical measurements for 14 subjects during maximal ballistic lower limb push-offs; its contribution to BLD was then investigated using a theoretical macroscopic approach, considering both the mechanical constraints of movement dynamics and the maximal external capabilities of the lower limb neuromuscular system. During ballistic lower limb push-off, the maximum force each lower limb can produce was lower during bilateral than unilateral actions, thus leading to a BLD of 36.7% ± 5.7%. The decrease in force due to the F-v mechanical properties amounted to 19.9% ± 3.6% of the force developed during BL push-offs, which represents a nonneural contribution to BLD of 43.5% ± 9.1%. This contribution to BLD that cannot be attributed to changes in neural features was negatively correlated to the maximum unloaded extension velocity of the lower limb (r = -0.977, P push-off, BLD is due to both neural alterations and F-v mechanical properties, the latter being associated with the change in movement velocity between bilateral and unilateral actions. The level of the contribution of the F-v properties depends on the individual F-v mechanical profile of the entire lower limb neuromuscular system: the more the F-v profile is oriented toward velocity capabilities, the lower the loss of force from unilateral to bilateral push-offs due to changes in movement velocity.

The behavioral implications of the bilateral gamma process

Science.gov (United States)

Xie, Haibin; Wang, Shouyang; Lu, Zudi

2018-06-01

Bilateral gamma process is widely used in risk management and asset pricing. However the behavioral implications of this process remain unknown. This paper investigates this problem for the first time within the framework of Tauchen and Pitts (1983). With the assumption that there are two types of traders in the market, the optimistic and the pessimistic, we find the bilateral gamma process can be derived from Walrasian equilibrium. This finding establishes the microstructure foundations for the bilateral gamma process.

[Atypical etiology of rhinorrhea: spontaneous bilateral temporal encephalocele].

Science.gov (United States)

Lorente Muñoz, Asís; Lisbona Alquézar, María Pilar; González Martínez, Luis; Sevil Navarro, Jorge; Llorente Arenas, Eva María

2012-01-01

Spontaneous herniation of brain parenchyma through a dural and osseous defect in the temporal bone is a rare entity and a bilateral form is even more infrequent. It usually presents as an intermittent but persistent otorrhea. Manifestation as nose cerebrospinal fluid (CSF) leak is very uncommon. Our objective is presenting this unusual case report of a spontaneous bilateral encephalocele with a bilateral tegmen tympani defect. Copyright © 2010 Elsevier España, S.L. All rights reserved.

Bilateral cerebellar activation in unilaterally challenged essential tremor

Directory of Open Access Journals (Sweden)

Marja Broersma

2016-01-01

Conclusions: Our results expand on previous findings of bilateral cerebellar involvement in ET. We have identified specific areas in the bilateral somatomotor regions of the cerebellum: lobules V, VI and VIII.

Bilateral symmetry detection on the basis of Scale Invariant Feature Transform.

Directory of Open Access Journals (Sweden)

Habib Akbar

Full Text Available The automatic detection of bilateral symmetry is a challenging task in computer vision and pattern recognition. This paper presents an approach for the detection of bilateral symmetry in digital single object images. Our method relies on the extraction of Scale Invariant Feature Transform (SIFT based feature points, which serves as the basis for the ascertainment of the centroid of the object; the latter being the origin under the Cartesian coordinate system to be converted to the polar coordinate system in order to facilitate the selection symmetric coordinate pairs. This is followed by comparing the gradient magnitude and orientation of the corresponding points to evaluate the amount of symmetry exhibited by each pair of points. The experimental results show that our approach draw the symmetry line accurately, provided that the observed centroid point is true.

Bilateral calcaneal epiphysiolysis in a dog.

Science.gov (United States)

Font, J; Pèlach, M; Font, C; Cairo, J

2013-01-01

A case of bilateral calcaneal epiphysiolysis in a six-month-old female Dobermann Pinscher is described in this report. The absence of a traumatic event and the clinical, radiographic and histopathological abnormalities led us to the diagnosis of simultaneous bilateral epiphysiolysis of the calcaneus. A tension band and a type II transarticular external fixator were placed. The clinical signs were resolved only temporarily because of the gravity of the bone changes.

New secure bilateral transaction determination and study of pattern under contingencies and UPFC in competitive hybrid electricity markets

International Nuclear Information System (INIS)

Kumar, A.; Chanana, S.

2009-01-01

In the competitive electricity environment, the flexibility of power transactions is expected to drastically increase among the trading partners and can compromise the system security and reliability. These transactions are to be evaluated ahead of their scheduling in a day-ahead and hour-ahead market to avoid congestion and ensure their feasibility with respect to the system operating conditions. The security of the transactions has become essential in the new environment for better planning and management of competitive electricity markets. This paper proposes a new method of secure bilateral transaction determination using AC distribution factors based on the full Jacobian sensitivity and considering the impact of slack bus for pool and bilateral coordinated markets. The secure bilateral transactions have also been determined considering critical line outage contingencies cases. The bilateral transaction matrix pattern has also been determined in the presence of unified power flow controller (UPFC). The optimal location of UPFC has been determined using mixed integer non-linear programming approach. The proposed technique has been applied on IEEE 24-bus reliability test system (RTS). (author)

Bilateral Ramsay Hunt syndrome in a diabetic patient

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Goyal Amit

2004-12-01

Full Text Available Abstract Background Herpes zoster oticus accounts for about 10% cases of facial palsy, which is usually unilateral and complete and full recovery occurs in only about 20% of untreated patients. Bilateral herpes zoster oticus can sometime occur in immunocompromised patients, though incidence is very rare. Case presentation Diabetic male, 57 year old presented to us with bilateral facial palsy due to herpes zoster oticus. Patient was having bilateral mild to moderate sensorineural hearing loss. Patient was treated with appropriate metabolic control, anti-inflammatory drugs and intravenous acyclovir. Due to uncontrolled diabetes, glucocorticoids were not used in this patient. Significant improvement in hearing status and facial nerve functions were seen in this patient. Conclusions Herpes zoster causes severe infections in diabetic patients and can be a cause of bilateral facial palsy and bilateral Ramsay Hunt syndrome. Herpes zoster in diabetic patients should be treated with appropriate metabolic control, NSAIDS and intravenous acyclovir, which we feel should be started at the earliest. Glucocorticoids should be avoided in diabetic patients.

Costing for the Future: Exploring Cost Estimation With Unmanned Autonomous Systems

Science.gov (United States)

2016-04-30

country terrain. Control modes include tethered , radio control, teleoperation (NLOS and BLOS), supervised autonomy, and voice command. TRL level is 7–9...Technology Conference and Balloon Systems Conference. Acknowledgments This material is based upon work supported by the Naval Postgraduate School

Rapid assessment of bilateral cochlear implantation for children in Kazakhstan.

Science.gov (United States)

Kosherbayeva, Lyazzat; Hailey, David; Kozhageldiyeva, Laura

2014-10-01

The aim of this study was to evaluate the effectiveness of bilateral cochlear implantation (CI) compared with unilateral CI for deaf children in the context of the Republic of Kazakhstan health system. Methods. A literature search was conducted, using the PubMed, Cochrane, and Embase data bases for studies that compared the effectiveness of bilateral and unilateral CI in children. The search included English language, publications from 2002-2012. Two reviewers independently evaluated all relevant studies. Administrative data relevant to CI in Kazakhstan were obtained from the Ministry of Health. Three relevant systematic reviews and an health technology assessment report were found. There was evidence of incremental benefits from bilateral CI but the quality of the available studies was poor and there was little information on longer term outcomes. No conclusions could be drawn regarding later incremental improvements to speech perception, learning, and quality of life. To date, in the Republic of Kazakhstan there is not full coverage of audiological screening due to the lack of medical equipment. This leads to late detection of hearing-impaired children and a long rehabilitation period, requiring more resources. Age of implantation in children is late and only a small minority attend general schools. The clinical effectiveness of bilateral CI, an expensive health technology, requires further study. Given the current situation in Kazakhstan with audiological screening and access to unilateral CI, there appeared to be other priorities for improving services for children with profound hearing impairment.

Bilateral Giant Retinal Tear and Sequential Vitrectomy.

Science.gov (United States)

Mustapha, Mushawiahti; Roufail Franzco, Edward

2017-01-01

To describe the excellent outcome of surgery for bilateral giant retinal tears (GRTs) with better options of endotamponade. This is a case report of a 62-year-old man who presented with bilateral GRTs and associated retinal detachment. The tear in the right eye was supero-temporal and silicone oil was used as an endotamponade. The tear in the left eye was infero-temporal and perfluorocarbon liquid was used as an endotamponade. The outcome at 6 months after surgery was excellent with visual acuities of 6/6 in both eyes. Improved availability of endotamponade agents allows repair of bilateral GRTs to be done at the same time, with good surgical outcomes.

Simultaneous bilateral cataract surgery: economic analysis; Helsinki Simultaneous Bilateral Cataract Surgery Study Report 2.

Science.gov (United States)

Leivo, Tiina; Sarikkola, Anna-Ulrika; Uusitalo, Risto J; Hellstedt, Timo; Ess, Sirje-Linda; Kivelä, Tero

2011-06-01

To present an economic-analysis comparison of simultaneous and sequential bilateral cataract surgery. Helsinki University Eye Hospital, Helsinki, Finland. Economic analysis. Effects were estimated from data in a study in which patients were randomized to have bilateral cataract surgery on the same day (study group) or sequentially (control group). The main clinical outcomes were corrected distance visual acuity, refraction, complications, Visual Function Index-7 (VF-7) scores, and patient-rated satisfaction with vision. Health-care costs of surgeries and preoperative and postoperative visits were estimated, including the cost of staff, equipment, material, floor space, overhead, and complications. The data were obtained from staff measurements, questionnaires, internal hospital records, and accountancy. Non-health-care costs of travel, home care, and time were estimated based on questionnaires from a random subset of patients. The main economic outcome measures were cost per VF-7 score unit change and cost per patient in simultaneous versus sequential surgery. The study comprised 520 patients (241 patients included non-health-care and time cost analyses). Surgical outcomes and patient satisfaction were similar in both groups. Simultaneous cataract surgery saved 449 Euros (€) per patient in health-care costs and €739 when travel and paid home-care costs were included. The savings added up to €849 per patient when the cost of lost working time was included. Compared with sequential bilateral cataract surgery, simultaneous bilateral cataract surgery provided comparable clinical outcomes with substantial savings in health-care and non-health-care-related costs. No author has a financial or proprietary interest in any material or method mentioned. Copyright © 2011 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

Bilateral paracoccidioidomycotic iliopsoas abscess associated with ileo-colonic lesion

Directory of Open Access Journals (Sweden)

Helena Duani

2012-10-01

Full Text Available This case report shows the clinical development of a patient with systemic paracoccidioidomycosis presenting with lymphatic-intestinalmanifestation. The patient initially had a substantial clinical improvement but had a recrudescence after six months of sulfamethoxazoletrimethoprim oral treatment, with the emergence of feverish syndrome, lumbar pain, and intermittent claudication, characterizing a bilateral iliopsoas muscle abscess, necessitating clinicosurgical therapeutics.

Bilateral tumors of the upper urothelium

Directory of Open Access Journals (Sweden)

Đokić Milan

2006-01-01

Full Text Available Introduction: The incidence of tumors of the upper urothelium is high in our country, apart from their relation to specific regions (BEN and PBEN and their frequent bilateralism. Bilateral forms are present in significant percentage and are followed, in most cases, by renal failure, which speaks in favor of conservative surgery, if possible. Objective: The aim of the study was to present epidemiological, pathoanatomical and clinical characteristics of bilateral tumors of the upper urothelium and evaluate the Results of their treatment. Method: Our retrospective study analyzed 12 patients with bilateral tumors of the upper urothelium who were treated in the period from 1992 to 1996, according to their epidemiological, clinical, pathoanatomical and pathohistological characteristics, type of surgical treatment and relevant success. Results: In the observed period, bilateral tumors of the upper urothelium were found in 8.2% of our patients. In the group of 12 patients, 5 females and 7 males, 11 cases were from the region of Balkan Endemic Nephropathy (BEN. Renal failure was recorded in high percentage (66%. Radical surgical treatment - total nephroureterectomy was performed in 9 kidney units, and conservative operation in 15 units. Relapse significantly depended on tumor stage and grade, not on type of surgical treatment in the majority of cases. Five-year survival was 58.33%; major cause of death was associated with further evolution of tumor, recurrence and tumor dissemination, respectively, while renal failure complications were the cause of death in one case. Conclusion: The success of treatment mainly depends on tumor stage and grade and not on type of surgical Method in conservative treatment, but renal failure and its complications are an important risk factor in these patients.

Real-Time Obstacle Avoidance for Telerobotic Systems Based on Equipotential Surface

Directory of Open Access Journals (Sweden)

Xin Li

2012-09-01

Full Text Available Redundant manipulators offer a dual advantage of flexibility and dexterity and can be used in many civilian and military areas. However, operating such systems by teleoperation is challenging because of the redundancy and unstructured task environment, which result in the human operator suffering a huge burden when telemanipulator is facing the complicated obstacles. The existing methods usually use some off-line algorithms to solve the problem of obstacle avoidance. It is difficult for them to meet the requirements of real-time teleoperation in some unknown environment. This paper presents an on-line method for a telerobotic system to take advantage of redundancy to avoid obstacle, which is based on real-time sensor information. With this method, the human operator can focus attention on the end-effector operation regardless of the obstacle avoidance of other parts. The effectiveness and advantage of the method are well demonstrated by experiments.

Pathogenesis and prognosis of bilateral thalamic infarction

International Nuclear Information System (INIS)

Nakase, Taizen; Ogura, Naoko; Maeda, Tetsuya; Yamazaki, Takashi; Kameda, Tomoaki; Sato, Yuichi; Nagata, Ken

2008-01-01

Only a few reports have discussed the detailed clinical symptoms and pathogenesis of bilateral thalamic infarction. The thalamus is composed of different functional nuclei and supplied by vessels containing several variations from the main arteries, leading to difficulty in the precise evaluation of bilateral thalamic infarction. In the present study, we assessed the prognosis of bilateral thalamic infarction based on the distribution of stroke lesions. From among the consecutive ischemic stroke patients admitted to hospital between April 2001 and March 2005, cases of acute bilateral thalamic infarction were selected for this study (n=9; 65.1±13.6 y.o.). The stroke lesions and vascular abnormalities were investigated by magnetic resonance imaging and magnetic resonance angiography on admission. Outcome was evaluated from the modified Rankin scale (mRS) at discharge. Good outcome patients (mRS 0-2; n=5) showed memory disturbance, cognitive impairment and hypersomnia. On the other hand, quadriplegia, oculomotor disturbance and bulbar palsy were observed in the poor outcome patients (mRS≥4; n=4). The critical features of a poor outcome were the age at onset (72.0±15.3 vs. 58.2±11.9 y.o.), inclusion of brainstem lesions and total occlusion of the basilar artery. In conclusion, older age at onset and/or basilar artery occlusion may be critical factors for predicting a poor outcome in bilateral thalamic infarction cases. (author)

Danish Exports and Danish Bilateral Aid

DEFF Research Database (Denmark)

Hansen, Henrik; Rand, John

higher in the 1980s compared to in particular the most recent decade. This may be related to factors such as untying of aid in the same period. The econometric analysis has two important limitations. First of all, the model can only give information about marginal changes in aid. As a decision to give...... and trade policies. The main result of the study is that Danish bilateral aid has a positive and statistically significant impact on Danish exports to the recipient countries. Bilateral development assistance may affect exports through several channels. Three of the main channels are direct aid tying......; increasing recipient income where higher income leads to higher imports, and decreased trade costs, say due to improved information about cultural and administrative customs and practices. Thus, as for preferential trade arrangements, bilateral aid has two potential economic effects; trade creation working...

Bilateral movements increase sustained extensor force in the paretic arm.

Science.gov (United States)

Kang, Nyeonju; Cauraugh, James H

2018-04-01

Muscle weakness in the extensors poststroke is a common motor impairment. Unfortunately, research is unclear on whether bilateral movements increase extensor force production in the paretic arm. This study investigated sustained force production while stroke individuals maximally extended their wrist and fingers on their paretic arm. Specifically, we determined isometric force production in three conditions: (a) unilateral paretic arm, (b) unilateral nonparetic arm, and (c) bilateral (both arms executing the same movement simultaneously). Seventeen chronic stroke patients produced isometric sustained force by executing wrist and fingers extension in unilateral and bilateral contraction conditions. Mean force, force variability (coefficient of variation), and signal-to-noise ratio were calculated for each contraction condition. Analysis of two-way (Arm × Type of Condition: 2 × 2; Paretic or Nonparetic Arm × Unilateral or Bilateral Conditions) within-subjects ANOVAs revealed that the bilateral condition increased sustained force in the paretic arm, but reduced sustained force in the nonparetic arm. Further, although the paretic arm exhibited more force variability and less signal-to-noise ratio than the nonparetic arm during a unilateral condition, there were no differences when participants simultaneously executed isometric contractions with both arms. Our unique findings indicate that bilateral contractions transiently increased extensor force in the paretic arm. Implications for Rehabilitation Bilateral movements increased isometric wrsit extensor force in paretic arms and redcued force in nonparetic arms versus unilateral movements. Both paretic and nonparetic arms produced similar force variability and signal-to-noise ratio during bilateral movements. Increased sustained force in the paretic arm during the bilateral condition indicates that rehabilitation protocols based on bilateral movements may be beneficial for functional recovery.

Synchronized Bilateral Synaptic Inputs to Drosophila melanogaster Neuropeptidergic Rest/Arousal Neurons

DEFF Research Database (Denmark)

McCarthy, E. V.; Wu, Y.; deCarvalho, T.

2011-01-01

Neuropeptide PDF (pigment-dispersing factor)-secreting large ventrolateral neurons (lLN(v)s) in the Drosophila brain regulate daily patterns of rest and arousal. These bilateral wake-promoting neurons are light responsive and integrate information from the circadian system, sleep circuits...

Coexistence of bilateral first and second branchial arch anomalies

Science.gov (United States)

Thakur, J S; Shekar, Vidya; Saluja, Manika; Mohindroo, N K

2013-01-01

Branchial arch anomalies are one of the most common congenital anomalies that are usually unilateral and bilateral presentation is rare. The simultaneous presence of bilateral second branchial arch anomalies along with bilateral first arch anomalies is extremely rare, with only three such cases reported in the literature. We present two non-syndromic cases of coexisting bilateral first and second arch anomalies. Developmental anomalies of the branchial apparatus account for 17% of all paediatric cervical masses and are the most common type of congenital cervical mass. They usually present in the paediatric age group. About 96–97% of these anomalies are unilateral. Bilateral presentation is seen in 2–3% having a strong familial association. Congenital syndromes also have been associated with first and second branchial arch anomalies. Thorough clinical examination and investigations should be done to rule out these syndromes. PMID:23580675

Associations of unilateral whisker and olfactory signals induce synapse formation and memory cell recruitment in bilateral barrel cortices: cellular mechanism for unilateral training toward bilateral memory

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Zilong Gao

2016-12-01

Full Text Available Somatosensory signals and operative skills learned by unilateral limbs can be retrieved bilaterally. In terms of cellular mechanism underlying this unilateral learning toward bilateral memory, we hypothesized that associative memory cells in bilateral cortices and synapse innervations between them were produced. In the examination of this hypothesis, we have observed that paired unilateral whisker and odor stimulations led to odorant-induced whisker motions in bilateral sides, which were attenuated by inhibiting the activity of barrel cortices. In the mice that showed bilateral cross-modal responses, the neurons in both sides of barrel cortices became to encode this new odor signal alongside the innate whisker signal. Axon projections and synapse formations from the barrel cortex, which was co-activated with the piriform cortex, toward its contralateral barrel cortex were upregulated. Glutamatergic synaptic transmission in bilateral barrel cortices was upregulated and GABAergic synaptic transmission was downregulated. The associative activations of the sensory cortices facilitate new axon projection, glutamatergic synapse formation and GABAergic synapse downregulation, which drive the neurons to be recruited as associative memory cells in the bilateral cortices. Our data reveals the productions of associative memory cells and synapse innervations in bilateral sensory cortices for unilateral training toward bilateral memory.

Spontaneous Unruptured Bilateral Tubal Pregnancy: A Case Report

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Nayereh Ghomian

2015-11-01

Full Text Available Bilateral spontaneous tubal ectopic pregnancy is the rarest form of extra uterine pregnancy. The diagnosis is usually made intraoperatively and levels of serum BHCG and ultrasound has not been useful in the diagnosis of bilateral tubal ectopic pregnancy. A 33-year-old woman with 8 weeks amenorrhea and sever lower abdominal pain was admitted. A transvaginal pelvic ultrasound revealed left adnexal mass and massive fluid collection in the pelvis and abdomen. The serum BHCG was 5,700 mIU/ml and in laparotomy bilateral unruptured tubal pregnancy was noted. Left salpingectomy and right salpingostomy were performed. The diagnosis of bilateral spontaneous tubal ectopic pregnancy is usually made intraoperatively. Both tubes at the time of surgery should be closely examined in order to prevent maternal morbidity and mortality.

Delayed-onset bilateral abducens paresis after head trauma

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Pravin Salunke

2012-01-01

Full Text Available Bilateral sixth nerve paresis following closed head injury, though rare, is a known entity. However, delayed-onset post-traumatic bilateral abducens paresis is extremely rare. We present two cases. The first patient had onset of bilateral abducens paresis 2 weeks after closed head injury and the second patient after 3 days. The cause in the former was detected to be chronic subdural hematoma and in the latter is speculated to be edema/ischemia due to injury to soft tissue structures housing these nerves. The delayed onset of bilateral abducens paresis following head injury may vary according to the cause. There may be another mechanism of injury apart from direct trauma. Though rare, it needs to be evaluated and may have a treatable cause like elevated intracranial pressure.

Diffusion MR Imaging of Postoperative Bilateral Acute Ischemic Optic Neuropathy

International Nuclear Information System (INIS)

Park, Ju Young; Lee, In Ho; Song, Chang June; Hwang, Hee Youn

2012-01-01

A 57-year-old woman experienced bilateral acute ischemic optic neuropathy after spine surgery. Routine MR imaging sequence, T2-weighted image, showed subtle high signal intensity on bilateral optic nerves. A contrast-enhanced T1 weighted image showed enhancement along the bilateral optic nerve sheath. Moreover, diffusion-weighted image (DWI) and an apparent diffusion coefficient map showed markedly restricted diffusion on bilateral optic nerves. Although MR findings of T2-weighted and contrast enhanced T1-weighted images may be nonspecific, the DWI finding of cytotoxic edema of bilateral optic nerves will be helpful for the diagnosis of acute ischemic optic neuropathy after spine surgery.

Diffusion MR Imaging of Postoperative Bilateral Acute Ischemic Optic Neuropathy

Energy Technology Data Exchange (ETDEWEB)

Park, Ju Young; Lee, In Ho; Song, Chang June [Chungnam National University Hospital, Daejeon (Korea, Republic of); Hwang, Hee Youn [Eulji University Hospital, Daejeon(Korea, Republic of)

2012-03-15

A 57-year-old woman experienced bilateral acute ischemic optic neuropathy after spine surgery. Routine MR imaging sequence, T2-weighted image, showed subtle high signal intensity on bilateral optic nerves. A contrast-enhanced T1 weighted image showed enhancement along the bilateral optic nerve sheath. Moreover, diffusion-weighted image (DWI) and an apparent diffusion coefficient map showed markedly restricted diffusion on bilateral optic nerves. Although MR findings of T2-weighted and contrast enhanced T1-weighted images may be nonspecific, the DWI finding of cytotoxic edema of bilateral optic nerves will be helpful for the diagnosis of acute ischemic optic neuropathy after spine surgery.

Bilateral anophthalmia with septo-optic dysplasia

OpenAIRE

Jana, Manisha; Sharma, Sanjay

2010-01-01

Bilateral anophthalmia is a rare entity and association with septo-optic dysplasia is an even rare condition. The condition is characterized by absent eyeballs in the presence of eyelids, conjunctiva or lacrimal apparatus. Though anophthalmia can be diagnosed clinically, imaging plays a crucial role in delineating the associated anomalies. In addition, often clinical anophthalmia may prove to be severe microphthalmia on imaging. We describe the imaging findings in an infant with bilateral ano...

Bilateral spontaneous adrenal haemorrhage complicating acute pancreatitis

International Nuclear Information System (INIS)

Pianta, M.; Varma, D. K.

2007-01-01

Bilateral adrenal haemorrhage is an event that mandates prompt diagnosis and treatment to prevent primary adrenocortical insufficiency and potential death. Presentation can be non-specific and incidentally diagnosed with imaging alone, primarily CT. We present a case of acute pancreatitis with spontaneous bilateral adrenal haemorrhage and briefly discuss imaging and treatment implications

Bilateral breast cancer after cured Hodgkin's disease

Energy Technology Data Exchange (ETDEWEB)

Anderson, N.; Lokich, J. (New England Baptist Hospital, Boston, MA (USA))

1990-01-15

Three patients developed bilateral breast cancer at 10 to 24 years after mantle irradiation for locally or systemically advanced Hodgkin's disease (HD). Four of the six cancers in the three patients were detected only by mammography. Pathologically, five of the cancers were intraductal carcinomas (four with an invasive component) with one being a lobular carcinoma. Five of the six lesions were Stage I pathologically without evidence of axillary nodal involvement. It is recommended that female patients with Hodgkin's disease who have received mantle irradiation as part of the therapy for their Hodgkin's disease and who are observed for 10 or more years after completion of mantle irradiation be considered at risk for the development of breast cancer. Such patients should be monitored appropriately by routine bilateral mammograms to increase the early detection of early stage lesions.

Developing Tele-Operated Laboratories for Manufacturing Engineering Education. Platform for E-Learning and Telemetric Experimentation (PeTEX

Directory of Open Access Journals (Sweden)

A. Erman Tekkaya

2010-09-01

Full Text Available The aim of the PeTEX-project is to establish an e-Learning platform for the development, implementation, and delivery of educational training programs in the field of manufacturing engineering. The PeTEX team designs both: a technical platform for eLearning based on “Moodle” including distributed tele-operated experimentation facilities, and didactic and socio-technical requirements for a successful online learning community. User interfaces are deployed for remote access to instruments, data analysis and multiplexed data access via network protocols. Hence, the platform provides complex tools in order to perform various activities to support the educational process, from telemetric experimentation to virtual project groups for an entire community to the purpose of domain specific learning. This paper describes important steps of interdisciplinary participatory design and development of a remote lab-prototype in the field of manufacturing engineering.

Mask face: bilateral simultaneous facial palsy in an 11-year-old boy.

Science.gov (United States)

Güngör, Serdal; Güngör Raif, Sabiha; Arslan, Müjgan

2013-04-01

Bilateral facial paralysis is an uncommon clinical entity especially in the pediatric age group and occurs frequently as a manifestation of systemic disease. The most important causes are trauma, infectious diseases, neurological diseases, metabolic, neoplastic, autoimmune diseases and idiopathic disease (Bell's palsy). We report a case of an 11-year-old boy presenting with bilateral simultaneous peripheral facial paralysis. All possible infectious causes were excluded and the patient was diagnosed as having Bell's palsy (idiopathic). The most important approach in these cases is to rule out a life-threatening disease. © 2013 The Authors. Pediatrics International © 2013 Japan Pediatric Society.

Combination nivolumab- and cabiralizumab-associated acute bilateral anterior and posterior scleritis and anterior uveitis

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John A. Gonzales

2018-06-01

Full Text Available Purpose: To report on a case of uveitis and scleritis resulting as an immune-mediated side effect of cancer immunotherapy with nivolumab and cabiralizumab. Observations: Bilateral anterior nongranulomatous anterior uveitis and bilateral diffuse anterior and posterior scleritis occurred following the use of combination cancer immunotherapy. The uveitis and scleritis resolved following temporary discontinuation of nivolumab and cabiralizumab as well as systemic prednisone. Conclusions and importance: Ophthalmologists should be aware of the possibility of acute ocular inflammation developing with cancer immunotherapy. Systemic corticosteroids play a first-line role in managing such immune-mediated side effects. Keywords: Uveitis, Scleritis, Cancer immunotherapy, Side effects, Nivolumab, Cabiralizumab

Sarcoidosis Presenting as Bilateral Vocal Fold Immobility.

Science.gov (United States)

Hintze, Justin M; Gnagi, Sharon H; Lott, David G

2018-05-01

Bilateral true vocal fold paralysis is rarely attributable to inflammatory diseases. Sarcoidosis is a rare but important etiology of bilateral true vocal fold paralysis by compressive lymphadenopathy, granulomatous infiltration, and neural involvement. We describe the first reported case of sarcoidosis presenting as bilateral vocal fold immobility caused by direct fixation by granulomatous infiltration severe enough to necessitate tracheostomy insertion. In addition, we discuss the presentation, the pathophysiology, and the treatment of this disease with a review of the literature of previously reported cases of sarcoidosis-related vocal fold immobility. Sarcoidosis should therefore be an important consideration for the otolaryngologist's differential diagnosis of true vocal fold immobility. Copyright © 2018 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

Bilateral chronic subdural hematoma

DEFF Research Database (Denmark)

Andersen-Ranberg, Nina Christine; Rom Poulsen, Frantz; Bergholt, Bo

2017-01-01

OBJECTIVE Bilateral chronic subdural hematoma (bCSDH) is a common neurosurgical condition frequently associated with the need for retreatment. The reason for the high rate of retreatment has not been thoroughly investigated. Thus, the authors focused on determining which independent predictors...... are associated with the retreatment of bCSDH with a focus on surgical laterality. METHODS In a national database of CSDHs (Danish Chronic Subdural Hematoma Study) the authors retrospectively identified all bCSDHs treated in the 4 Danish neurosurgical departments over the 3-year period from 2010 to 2012...... that a separated hematoma density and the absence of postoperative drainage were independent predictors of retreatment. CONCLUSIONS In bCSDHs bilateral surgical intervention significantly lowers the risk of retreatment compared with unilateral intervention and should be considered when choosing a surgical...

IgG4-Related Disease of Bilateral Temporal Bones.

Science.gov (United States)

Li, Lilun; Ward, Bryan; Cocks, Margaret; Kheradmand, Amir; Francis, Howard W

2017-03-01

IgG4-related disease (IgG4-RD) is an idiopathic inflammatory condition that causes pseudotumor formation in single or multiple organs, including those of the head and neck. Temporal bone involvement is rare, with only 3 cases of unilateral temporal bone IgG4-RD described in the literature. We report the first known case of IgG4-RD of bilateral temporal bones and describe its clinical presentation, diagnosis, and treatment. The patient was a 52-year-old man with latent tuberculosis (TB) who presented with a 10-year history of bilateral profound hearing loss and vestibular dysfunction. Computed tomography and magnetic resonance imaging demonstrated bilateral labyrinthine destruction with invasion of the posterior fossa. Immunoglobulin level testing showed elevated total serum IgG levels with normal IgG4 levels. Bilateral mastoidectomies were performed, with biopsy samples demonstrating IgG4 staining with IgG4-positive plasma cells up to 40/HPF (high power field) on the right and 20/HPF on the left, consistent with bilateral IgG4-RD. IgG4-RD of bilateral temporal bones presents with chronic and progressive bilateral hearing loss and vestibular dysfunction. Clinical presentation and radiologic findings are nonspecific, and definitive diagnosis must be made with histopathology and immunostaining. Corticosteroids are therapeutic, but surgical resection may be necessary for temporal bone IgG4-RD to improve long-term remission.

Unilateral versus bilateral thyroarytenoid Botulinum toxin injections in adductor spasmodic dysphonia: a prospective study

Science.gov (United States)

Upile, Tahwinder; Elmiyeh, Behrad; Jerjes, Waseem; Prasad, Vyas; Kafas, Panagiotis; Abiola, Jesuloba; Youl, Bryan; Epstein, Ruth; Hopper, Colin; Sudhoff, Holger; Rubin, John

2009-01-01

Objectives In this preliminary prospective study, we compared unilateral and bilateral thyroarytenoid muscle injections of Botulinum toxin (Dysport) in 31 patients with adductor spasmodic dysphonia, who had undergone more than 5 consecutive Dysport injections (either unilateral or bilateral) and had completed 5 concomitant self-rated efficacy and complication scores questionnaires related to the previous injections. We also developed a Neurophysiological Scoring (NPS) system which has utility in the treatment administration. Method and materials Data were gathered prospectively on voice improvement (self-rated 6 point scale), length of response and duration of complications (breathiness, cough, dysphagia and total voice loss). Injections were performed under electromyography (EMG) guidance. NPS scale was used to describe the EMG response. Dose and unilateral/bilateral injections were determined by clinical judgment based on previous response. Time intervals between injections were patient driven. Results Low dose unilateral Dysport injection was associated with no significant difference in the patient's outcome in terms of duration of action, voice score (VS) and complication rate when compared to bilateral injections. Unilateral injections were not associated with any post treatment total voice loss unlike the bilateral injections. Conclusion Unilateral low dose Dysport injections are recommended in the treatment of adductor spasmodic dysphonia. PMID:19852852

Unilateral versus bilateral thyroarytenoid Botulinum toxin injections in adductor spasmodic dysphonia: a prospective study

Directory of Open Access Journals (Sweden)

Abiola Jesuloba

2009-10-01

Full Text Available Abstract Objectives In this preliminary prospective study, we compared unilateral and bilateral thyroarytenoid muscle injections of Botulinum toxin (Dysport in 31 patients with adductor spasmodic dysphonia, who had undergone more than 5 consecutive Dysport injections (either unilateral or bilateral and had completed 5 concomitant self-rated efficacy and complication scores questionnaires related to the previous injections. We also developed a Neurophysiological Scoring (NPS system which has utility in the treatment administration. Method and materials Data were gathered prospectively on voice improvement (self-rated 6 point scale, length of response and duration of complications (breathiness, cough, dysphagia and total voice loss. Injections were performed under electromyography (EMG guidance. NPS scale was used to describe the EMG response. Dose and unilateral/bilateral injections were determined by clinical judgment based on previous response. Time intervals between injections were patient driven. Results Low dose unilateral Dysport injection was associated with no significant difference in the patient's outcome in terms of duration of action, voice score (VS and complication rate when compared to bilateral injections. Unilateral injections were not associated with any post treatment total voice loss unlike the bilateral injections. Conclusion Unilateral low dose Dysport injections are recommended in the treatment of adductor spasmodic dysphonia.

Outcome of bilateral ureteroscopic retrieval of stones in a single session

Directory of Open Access Journals (Sweden)

Majid Mushtaque

2012-01-01

Conclusion: Bilateral same-session ureteroscopy is a safe and effective procedure in the management of bilateral ureteral stones. The results are comparable to unilateral or staged bilateral procedures.

Essure insert expulsion after 3-month hysterosalpingogram confirmation of bilateral tubal occlusion and bilateral correct placement: case report.

Science.gov (United States)

Garcia, Amy L; Lewis, Rae M; Sloan, Anita Lee

2013-01-01

Essure hysteroscopic sterilization is an effective permanent contraception option for women, with a 99.83% effectiveness rate. To date, more than 600,000 Essure procedures have been performed worldwide. This case report describes bilateral Essure insert placement, after which the left insert was subsequently expelled after hysterosalpingogram (HSG)-confirmed correct bilateral insert placement and bilateral tubal occlusion. Although insert expulsion has been reported before a 3-month post-procedure HSG, this is the first published report of expulsion after a confirmatory 3-month post-procedure HSG. Because there now exists documentation of Essure insert expulsion after a 3-month confirmatory HSG, physicians and patients should be informed of this rare occurrence. Further investigation into the causes of such an event is warranted. Copyright © 2013 AAGL. Published by Elsevier Inc. All rights reserved.

Bilateral anophthalmia with septo-optic dysplasia

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Manisha Jana

2010-01-01

Full Text Available Bilateral anophthalmia is a rare entity and association with septo-optic dysplasia is an even rare condition. The condition is characterized by absent eyeballs in the presence of eyelids, conjunctiva or lacrimal apparatus. Though anophthalmia can be diagnosed clinically, imaging plays a crucial role in delineating the associated anomalies. In addition, often clinical anophthalmia may prove to be severe microphthalmia on imaging. We describe the imaging findings in an infant with bilateral anophthalmia and septo-optic dysplasia.

Congenital bilateral neuroblastoma (stage IV-S): case report

International Nuclear Information System (INIS)

Lee, Jeong Hee; Lee, Hee Jung; Woo, Seong Ku; Lee, Sang Rak; Kim, Heung Sik

2002-01-01

Congenital neonatal neuroblastoma is not uncommon but bilateral adrenal neuroblastoma is rare, accounting for about ten percent of neuroblastomas in children. We report the US the MR findings of a stage IV-S congenital bilateral neuroblastoma occurring in a one-day-old neonate

Development of a teleoperated backhoe for buried waste excavation

International Nuclear Information System (INIS)

Burks, B.L.; Killough, S.M.; Thompson, D.H.

1992-01-01

For nearly five decades the United States (US) Department of Energy (DOE) and its predecessor agencies have engaged in broad-based research and development activities as well as nuclear weapons component production. As a by-product of these activities, large quantities of waste materials have been granted. One of the most common approaches used for solid waste storage was to bury waste containers in pits and trenches. With the current emphasis on environmental restoration, DOE now plans to either retrieve much of the legacy of buried waste or stabilize the waste in place via in situ vitrification or other means. Because of the variety of materials that have been buried over the years, the hazards of retrieval are significant if performed using conventional manned operations. The potential hazards, in addition to radiation exposure, include pyrophorics, toxic chemicals, and explosives. Although manifests exist for much of the buried waste, these records are often incomplete compared to today's requirements. Because of the potential hazards and uncertainty about waste contents and container integrity, it is highly desirable to excavate these wastes using remotely operated equipment. In this paper the authors describe the development of a teleoperated military tractor called the Small Emplacement Excavator (SEE). Development of the SEE is being funded jointly by both DOE and the US Army. The DOE sponsor is the Office of Technology Development (OTD) Robotics Program. The US Army sponsor is the Program Manager for Ammunition Logistics, Picatinny Arsenal. The primary interest for DOE is in the application to remote excavation of buried waste, while the primary emphasis for the US Army is in the remote retrieval of unexploded ordnance. Technical requirements for these two tasks are very similar and, therefore, justify a joint development project. 1 ref

A case of bilateral vocal fold mucosal bridges, bilateral trans-vocal fold type III sulci vocales, and an intracordal polyp.

Science.gov (United States)

Tan, Melin; Pitman, Michael J

2011-07-01

We present a patient with a novel finding of bilateral mucosal bridges, bilateral type III trans-vocal fold sulci vocales, and a vocal fold polyp. Although sulci and mucosal bridges occur in the vocal folds, it is rare to find multiples of these lesions in a single patient, and it is even more uncommon when they occur in conjunction with a vocal fold polyp. To our knowledge, this is the first description of a vocal fold polyp in combination with multiple vocal fold bridges and multiple type III sulci vocales in a single patient. To describe and visually present the diagnosis and treatment of a patient with an intracordal polyp, bilateral mucosal bridges, as well as bilateral type III trans-vocal fold sulci vocales. Presentation of a set of high definition intraoperative photos displaying the extent of the vocal fold lesions and the resection of the intracordal polyp. This patient presented with only 6 months of significant dysphonia. It was felt that the recent change in voice was because of the polyp and not the bridges or sulci vocales. Considering the patient's presentation and the possible morbidity of resection of mucosal bridges and sulci, only the polyp was excised. Postoperatively, the patient's voice returned to his acceptable mild baseline dysphonia, and the benefit has persisted 6 months postoperatively. The combination of bilateral mucosal bridges, bilateral type III sulcus vocalis, and an intracordal polyp in one patient is rare if not novel. Treatment of the polyp alone returned the patient's voice to his lifelong baseline of mild dysphonia. Copyright © 2011 The Voice Foundation. Published by Mosby, Inc. All rights reserved.

Mobile Intelligent Autonomous Systems

OpenAIRE

Jitendra R. Raol; Ajith Gopal

2010-01-01

Mobile intelligent autonomous systems (MIAS) is a fast emerging research area. Although it can be regarded as a general R&D area, it is mainly directed towards robotics. Several important subtopics within MIAS research are:(i) perception and reasoning, (ii) mobility and navigation,(iii) haptics and teleoperation, (iv) image fusion/computervision, (v) modelling of manipulators, (vi) hardware/software architectures for planning and behaviour learning leadingto robotic architecture, (vii) ve...

Fibrovascular tissue in bilateral juxtafoveal telangiectasis.

Science.gov (United States)

Park, D; Schatz, H; McDonald, H R; Johnson, R N

1996-09-01

To study the natural history and retinal findings associated with the intraretinal and subretinal fibrovascular tissues that develop in the late phases of bilateral juxtafoveal telangiectasis. The records of 10 patients (11 eyes) with bilateral juxtafoveal telangiectasis who developed these fibrovascular tissues were examined. Throughout the follow-up period (average 44 months), only 2 eyes (18%) lost 2 or more lines of vision; the final visual acuities were similar for the eyes both with and without fibrovascular tissues. Sixty-four percent of fibrovascular tissues showed little to no growth. Eyes with fibrovascular tissue commonly had retinal pigment epithelial hyperplasia (72%), draining retinal venules (82%), and retinal vascular distortion (64%). Fibrovascular tissues of bilateral juxtafoveal telangiectasis have little proliferative potential and minimal effects on visual acuity. Nevertheless, these fibrovascular tissues do remodel over time, leading to retinal vascular distortion. Given these benign findings, the role of laser photocoagulation treatment of these tissues is questionable.

Natural interaction for unmanned systems

Science.gov (United States)

Taylor, Glenn; Purman, Ben; Schermerhorn, Paul; Garcia-Sampedro, Guillermo; Lanting, Matt; Quist, Michael; Kawatsu, Chris

2015-05-01

Military unmanned systems today are typically controlled by two methods: tele-operation or menu-based, search-andclick interfaces. Both approaches require the operator's constant vigilance: tele-operation requires constant input to drive the vehicle inch by inch; a menu-based interface requires eyes on the screen in order to search through alternatives and select the right menu item. In both cases, operators spend most of their time and attention driving and minding the unmanned systems rather than on being a warfighter. With these approaches, the platform and interface become more of a burden than a benefit. The availability of inexpensive sensor systems in products such as Microsoft Kinect™ or Nintendo Wii™ has resulted in new ways of interacting with computing systems, but new sensors alone are not enough. Developing useful and usable human-system interfaces requires understanding users and interaction in context: not just what new sensors afford in terms of interaction, but how users want to interact with these systems, for what purpose, and how sensors might enable those interactions. Additionally, the system needs to reliably make sense of the user's inputs in context, translate that interpretation into commands for the unmanned system, and give feedback to the user. In this paper, we describe an example natural interface for unmanned systems, called the Smart Interaction Device (SID), which enables natural two-way interaction with unmanned systems including the use of speech, sketch, and gestures. We present a few example applications SID to different types of unmanned systems and different kinds of interactions.

Fast-track surgery for bilateral total knee replacement

DEFF Research Database (Denmark)

Husted, H; Troelsen, A; Otte, K S

2011-01-01

Bilateral simultaneous total knee replacement (TKR) has been considered by some to be associated with increased morbidity and mortality. Our study analysed the outcome of 150 consecutive, but selected, bilateral simultaneous TKRs and compared them with that of 271 unilateral TKRs in a standardised...

Simultaneous bilateral anterior cruciate ligament reconstruction: Cost comparison and functional results

Directory of Open Access Journals (Sweden)

Matjaž Sajovic

2014-04-01

Full Text Available Background: The ideal treatment for patients presenting with bilateral anterior cruciate ligament (ACL deficiency remains controversial. The purpose was to evaluate cost and mid-term functional results after one-stage bilateral ACL reconstruction using either hamstring or patella tendon autograft.Methods: We compared the mid-term outcome of 7 patients (14 knees who had one-stage bilateral ACL reconstruction with that of a matched group of patients who had unilateral reconstruction (21 patients.Results: The median duration of hospital stay was 4 nights (range 3 to 5 for the bilateral group and 2 nights (range, 1 to 4 for the control group. The duration of rehabilitation process in patients from the control group with unilateral ACL reconstruction was one week shorter (9 versus 8 weeks. In the bilateral group, the median Lysholm score was 96 (range 85–100 and in the control group, the median score was 93 (range 81–100. The median time to return to full-time work and to full sports was 9 weeks and 7 months for the simultaneous bilateral group and 8 weeks and 6 months for the unilateral group. Six patients (86 % in the bilateral group and 17 patients (81 % in the control group were still performing at their pre-injury level of activity. The Health Insurance Institute of Slovenia saves EUR 2,925 when we perform simultaneous bilateral ACL reconstruction instead of two stage ACL reconstruction.Conclusions: Mid-term clinical results suggested that simultaneous bilateral ACL reconstruction using either hamstring or patella tendon autograft is clinically effective. For patients presenting with symptomatic bilateral ACL deficient knees, one stage bilateral ACL reconstruction is reproducible, cost effective, and does not compromise functional results.

Laparoscopic Partial Adrenalectomy for Bilateral Cortisol-secreting Adenomas

Directory of Open Access Journals (Sweden)

Jeffrey P. Domino

2007-04-01

Full Text Available Bilateral cortisol-secreting adenomas are a rare cause of Cushing's syndrome. We report a case of a 35-year-old woman who presented with ACTH-independent Cushing's syndrome and bilateral adrenal adenomas. Adrenal venous sampling confirmed both adenomas to be hyper-secreting cortisol. She underwent bilateral laparoscopic adrenalectomy; total right and partial left adrenalectomies. At 2-year follow-up, she is maintained on low-dose fludrocortisone and hydrocortisone, and without recurrence of hypercorticolism. Laparoscopic partial adrenalectomy is a feasible option for this rare condition; however, long-term follow-up is needed to determine her total independence from steroid usage.

Telerobotics in hazardous environments

International Nuclear Information System (INIS)

Bicker, R.; Glennie, D.; Ow, S.M.

1996-01-01

A bilateral force reflecting telerobotic system has been developed that allows the slave robot to be operated either manually, as in a conventional teleoperator system, or autonomously as a sensor driven robot. The implementation of shared control provides additional functionality which permits the operator to manually control the position (and/or velocity) of selected axes, whilst the remaining axes are controlled autonomously, using active force control. The force control scheme utilizes an active compliance algorithm to maintain the slave end-effector in contact with the workpiece at a prescribed force (or torque) along selected axes. The control system architecture is based on a network of parallel processors. A Puma 260 robot has been adapted as a force reflecting generalised manual input device and a Puma 760 robot has been configured to operate using force control as the slave robot. (UK)

Defining the Levels of Adjustable Autonomy: A Means of Improving Resilience in an Unmanned Aerial System

Science.gov (United States)

2014-09-01

implemented in a system, some level of human-operator involvement will be required in interacting with that system (Glas and Kanda 2012). This is the...September 23–24, 2010. Glas, Dylan F., Takayuki Kanda , Hiroshi Ishiguro, and Norihiro Hagita. 2012. Teleoperation of Multiple Social Robots." IEEE

Acute otitis media associated bilateral sudden hearing loss: case report and literature review.

Science.gov (United States)

Smith, A; Gutteridge, I; Elliott, D; Cronin, M

2017-07-01

Sudden sensorineural hearing loss is a rare otological condition with potential for dire outcomes including permanent hearing loss. Although the majority of cases are deemed idiopathic, bilateral sudden sensorineural hearing loss represents a rare subset typically related to systemic conditions, with higher morbidity and mortality. A controversial association with acute otitis media has been reported, with few bilateral cases published in the literature. A very rare case of bilateral sudden sensorineural hearing loss associated with acute otitis media is described, with a review of the literature. The limited evidence available suggests that acute otitis media with tinnitus and/or bacterial pathology may have an increased risk of sudden sensorineural hearing loss, which is consistent with the case described. Although there is no sufficiently powered published evidence to provide definitive treatment guidelines, the literature reviewed suggests that early myringotomy and antibiotics may greatly improve treatment outcomes.

Severe Bilateral Breast Mucinous Carcinoma with Bilateral Lungs and Cutaneous Metastasis: A Case Report and Literature Review

Directory of Open Access Journals (Sweden)

Rong Pu

2018-01-01

Full Text Available The case of a female who had severe, rare, terminal breast mucinous carcinoma (BMC and failed to receive surgery and chemotherapy was reported. The patient was diagnosed with pure BMC (ER++, PR++, CerbB-2−, and Ki-67 10% accompanied with bilateral lungs, bilateral chest walls with skin ulcer (D = 14 cm, lymph nodes of bilateral armpits, and right supraclavicular metastases. ECOG (Eastern Cooperative Oncology Group and NRS (Numeric Rating Scale pain scores were 4 and 6, respectively. Because the patient refused traditional chemotherapy and radiotherapy on religious grounds, an herbal medicine containing Panax ginseng, Agrimonia pilosa, and white flower Patrinia herb was administered; extensive nursing for tumor debridement was also provided. Quality of Life (QOL improved and pain reduced. Tumor-bearing survival time was prolonged. The present case dictates that herbal extract medicines and supportive treatment can be helpful for uncommon severe BMC as an appropriate alternative treatment.

Passivity-based control and estimation in networked robotics

CERN Document Server

Hatanaka, Takeshi; Fujita, Masayuki; Spong, Mark W

2015-01-01

Highlighting the control of networked robotic systems, this book synthesizes a unified passivity-based approach to an emerging cross-disciplinary subject. Thanks to this unified approach, readers can access various state-of-the-art research fields by studying only the background foundations associated with passivity. In addition to the theoretical results and techniques,  the authors provide experimental case studies on testbeds of robotic systems  including networked haptic devices, visual robotic systems,  robotic network systems and visual sensor network systems. The text begins with an introduction to passivity and passivity-based control together with the other foundations needed in this book. The main body of the book consists of three parts. The first examines how passivity can be utilized for bilateral teleoperation and demonstrates the inherent robustness of the passivity-based controller against communication delays. The second part emphasizes passivity’s usefulness for visual feedback control ...

Bilateral cerebellopontine arachnoid cyst: A rare entity.

Science.gov (United States)

Sharma, Anand; Sharma, Achal; Mittal, Radhey S; Gandhi, Ashok

2015-01-01

Bilateral cerebellopontine angle (CPA) arachnoid cysts (ACs) are very rare: only one case is reported in literature. Pathogenesis of those cysts is unknown; they are thought to be congenital. The presenting symptoms of CPA AC are frequently nonspecific or otological. The management of ACs of the CPA is controversial. We are reporting two cases of bilateral CPA AC with their pathophysiology and review of literature.

Bilateral nanophthalmos and pigmentary retinal dystrophy--an unusual syndrome.

Science.gov (United States)

Proença, Helena; Castanheira-Dinis, A; Monteiro-Grillo, M

2006-09-01

To report the clinical picture of the rare association of nanophthalmos and pigmentary retinal dystrophy and its cataract surgery outcome. We report a case of a 60-year-old female who presented with bilateral slowly progressive visual loss. The patient presented with bilateral light perception visual acuity, exotropia, brunescent cataract hindering fundus examination and hypodontia. Ultrasonography revealed bilateral nanophthalmos. A visual-evoked potential was also performed preoperatively. Cataract surgery with +40D IOL implantation was uneventful. Postoperative fundus examination revealed pigmentary retinal dystrophy, confirmed by electrophysiologic tests. Glycosaminoglycan urinary excretion was normal. Congenital bilateral nanophthalmos may rarely be associated with pigmentary retinal dystrophy. We suggest thorough preoperative evaluation in nanophthalmic eyes for the exclusion of significant features concerning visual prognosis.

Synchronous bilateral male breast cancer: a case report.

Science.gov (United States)

Sun, Woo-Young; Lee, Ki-Hyeong; Lee, Ho-Chang; Ryu, Dong-Hee; Park, Jin-Woo; Yun, Hyo-Young; Song, Young-Jin

2012-06-01

Synchronous bilateral breast cancer is extremely rare in men and has not, up to date, been reported in Korea. A 54-year-old man presented with a palpable mass in the right breast. The right nipple was retracted and bilateral axillary accessory breasts and nipples were present. On physical examination, a 2 cm-sized mass was palpated directly under the right nipple, and, with squeezing, bloody discharge developed in a single duct of the left nipple. There was no palpable mass in the left breast, and axillary lymph nodes were not palpable. Physical examination of external genitalia revealed a unilateral undescended testis on the left side. Synchronous bilateral breast cancer was diagnosed using mammography, ultrasonography, and core-needle biopsy. Histopathological examination revealed invasive ductal carcinoma in the right breast and ductal carcinoma in situ in the left breast. Bilateral total mastectomy, sentinel lymph node biopsy, and excision of accessory breasts in the axilla were performed.

Bilateral patellar tuberculosis masquerading as infected infrapatellar bursitis.

Science.gov (United States)

Sreenivasan, Ravi; Haq, Rehan Ul

2017-04-01

A 30-year-old woman presented to our outpatient department with complaints of pain and swelling in bilateral infrapatellar regions and a discharging sinus in the right knee over the duration of one year. Radiographs showed lytic regions in bilateral patellae. Samples sent from material curetted from sinus yielded no organism but histopathology reported granulomatous inflammation. Following a fresh magnetic resonance imaging (MRI) scan that revealed the infrapatellar pad of fat communicating with the patellar lesions, an exploration and evacuation was done. Material sent revealed epithelioid cell granulomas with caseous necrosis consistent with tuberculosis (TB). The patient was put on first line anti-tubercular treatment (ATT) and has responded favourably with healing of sinus and patellar lesions. Bilateral infrapatellar bursitis is not rare. However patellar TB as a cause for OMIT is not a common diagnosis. A bilateral patellar involvement has not been reported in literature to the best of our knowledge.

[A case of Crow-Fukase syndrome with respiratory failure due to bilateral diaphragmatic paralysis].

Science.gov (United States)

Namekawa, Michito; Muramatsu, Shin-ichi; Hashimoto, Ritsuo; Kawakami, Tadataka; Fujimoto, Ken-ichi; Nakano, Imaharu

2002-07-01

A 62-year-old man with well-controlled diabetes mellitus developed numbness of the bilateral feet and hands, followed by subacutely progressive weakness and amyotrophy of extremities. He became bed-ridden state, and dyspnea also appeared, so he was referred to our hospital. Physical examination revealed a lean man, with dark-reddish skin pigmentation, crabbed fingers, bilateral pretibial pitting edema, and bristles in extremities. Thoracoabdominal paradoxical respiration was observed and pulmonary vesicular sounds was decreased markedly in the both lungs. Laboratory data revealed hypoproteinemia, abnormalities of endocrine system, but M-protein was not detected. Serum vascular endothelial growth factor level was quite high. Chest radiography revealed elevation of the bilateral diaphragm, the % vital capacity (%VC) was 24%, and arterial blood gas analysis showed marked hypoxia with hypercapnia. These findings suggested that his respiratory failure was induced by bilateral diaphragmatic paralysis caused by bilateral phrenic nerve palsy due to Crow-Fukase syndrome. He became somnolent because of hypercapnic narcosis, so non-invasive positive pressure ventilation (NIPPV) was started. We treated him with intravenous immunoglobulin and oral corticosteroids therapies, and after these therapies, his symptoms were remarkably recovered and NIPPV became unnecessary soon. The most frequent causes of respiratory failure in Crow-Fukase syndrome are pleural effusion and pulmonary hypertension, and only two cases of this syndrome with respiratory failure caused by bilateral diaphragmatic paralysis were reported until now. When the patients with Crow-Fukase syndrome complain of dyspnea, we should take the diaphragmatic paralysis into consideration, which may be improved by appropriate therapies.

LOKI: a practical modelling and support system for telepresence systems

International Nuclear Information System (INIS)

Griffin, M.; Bridgewater, C.E.

1993-01-01

The use of Virtual Reality headset systems, in combination with a tele-presence ''head'' is discussed. The system is attached to a Unimate Puma robot arm and manipulated by the operator, using information gathered by the camera and auditory system, displayed via the Virtual Reality helmet. Operator commands are cross checked by using a modelling system, held on the Virtual Reality system. This system was found to supply a good sense of spacial awareness of the robot's domain. Actions which might move the robot outside its suitable operating envelope, or create a collision with the environment, were successfully blocked. This approach is seen as useful within the area of tele-operation. (author)

Teleoperated robotic sorting system

Science.gov (United States)

Roos, Charles E.; Sommer, Edward J.; Parrish, Robert H.; Russell, James R.

2000-01-01

A method and apparatus are disclosed for classifying materials utilizing a computerized touch sensitive screen or other computerized pointing device for operator identification and electronic marking of spatial coordinates of materials to be extracted. An operator positioned at a computerized touch sensitive screen views electronic images of the mixture of materials to be sorted as they are conveyed past a sensor array which transmits sequences of images of the mixture either directly or through a computer to the touch sensitive display screen. The operator manually "touches" objects displayed on the screen to be extracted from the mixture thereby registering the spatial coordinates of the objects within the computer. The computer then tracks the registered objects as they are conveyed and directs automated devices including mechanical means such as air jets, robotic arms, or other mechanical diverters to extract the registered objects.

Preliminary evaluation of the Accident Response Mobile Manipulation System for accident site salvage operations

International Nuclear Information System (INIS)

Trujillo, J.M.; Morse, W.D.; Jones, D.P.

1994-01-01

This paper describes and evaluates operational experiences with the Accident Response Mobile Manipulation System (ARMMS) during simulated accident site salvage operations which might involve nuclear weapons. The ARMMS is based upon a teleoperated mobility platform with two Schilling Titan 7F Manipulators

Early onset bilateral juvenile myasthenia gravis masquerading as simple congenital ptosis

Directory of Open Access Journals (Sweden)

Alam, Md. Shahid

2017-03-01

Full Text Available Myasthenia gravis is an autoimmune disorder affecting the neuromuscular junction. Ocular myasthenia gravis presents as ptosis with extraocular motility restriction and is prone to be misdiagnosed as third nerve palsy or congenital or aponeurotic ptosis. Juvenile ocular myasthenia gravis in very young children is difficult to diagnose and can be easily labeled as a case of congenital ptosis, the more so when the condition is bilateral. We present a case of a two-year-old child who presented with bilateral ptosis and was diagnosed as a case of simple congenital ptosis elsewhere with the advice to undergo tarsofrontalis sling surgery. The child was diagnosed with juvenile myasthenia gravis on thorough history, examination, and systemic evaluation and was started on anti-myasthenic treatment.

Homogeneous bilateral block shifts

Indian Academy of Sciences (India)

Douglas class were classified in [3]; they are unilateral block shifts of arbitrary block size (i.e. dim H(n) can be anything). However, no examples of irreducible homogeneous bilateral block shifts of block size larger than 1 were known until now.

Robust and Transparent Multi-Degree-of-Freedom Bilateral Teleoperation with Time-Delay

NARCIS (Netherlands)

Pinto Rebelo, J.L.

2015-01-01

Robots are particularly well suited for executing tasks that take place in locations which are too dangerous or inaccessible to human operators. For robot manipulators to execute complex activities in unknown, unstructured environments, despite the recent increases in computation power, human input

US findings of bilateral primary breast cancer: Retrospective study

International Nuclear Information System (INIS)

Lou Li; Cong Xinli; Yu Guofang; Li Jichang; Ma Yuxiang

2007-01-01

Background: For women with breast cancer, the contralateral breast is at high risk. The bilateral cancers may be synchronous or metachronous. If the bilateral breast cancers have similar ultrasonography (US) appearances, the US findings of the first breast cancer (index cancer) might lead to early detection of the contralateral cancer. The purpose of this study was to identify the US characteristics of bilateral breast cancer and to determine whether bilateral breast cancers have similar US appearances and whether the US findings for one breast cancer might be predictive of the contralateral breast cancer. Methods: We retrospectively reviewed the US manifestations of 58 patients with surgically proven bilateral primary breast cancer and compared the contralateral cancer with the index cancer by evaluation the margin, shape, inside echoes, posterior attenuation, calcification and color flow signals of 58 lesion pairs to investigate whether the bilateral breast cancers have similar US appearances. Results: Bilateral primary breast cancers were more located in upper outer quadrant, frequently spiculation, taller than wide shape, with irregular margin, heterogeneous internal echo and acoustic shadowing, containing microcalcification and abundant color flow signals. The most common US appearances were taller than wide shape (75.0%, 87/116), irregular margins (79.3%, 92/116) and heterogeneous internal echo (86.2%, 100/116). Of the total 58 lesion pairs, 18 (31.0%) pairs had similar US characteristics, whereas 40 (69.0%) pairs had different US characteristics. Conclusions: US signs of the index cancer do not indicate the most likely appearance of the second cancer in the contralateral breast. Evaluation of the contralateral cancer should be performed without regard for the US findings for the index cancer

The unpredictable outcomes of bilateral simultaneous fractures of ...

African Journals Online (AJOL)

Bilateral simultaneous fractures of Neck of Femur (NOF) are rare. They result amongst others from trauma, metabolic disease, electro-convulsion and simple falls. We report two cases of 40-year-old and 74-year-old females who presented with bilateral simultaneous fractures of NOF post simple falls. Both patients had ...

Strabismus developing after unilateral and bilateral cataract surgery in children

Science.gov (United States)

David, R; Davelman, J; Mechoulam, H; Cohen, E; Karshai, I; Anteby, I

2016-01-01

Purpose To evaluate the prevalence and risk factors of strabismus in children undergoing surgery for unilateral or bilateral cataract with or without intraocular lens implantation. Methods Medical records of pediatric patients were evaluated from 2000 to 2011. Children undergoing surgery for unilateral or bilateral cataract with at least 1 year of follow-up were included. Children with ocular trauma, prematurity, or co-existing systemic disorders were excluded. The following data were evaluated: strabismus pre- and post-operation; age at surgery; post-operative aphakia or pseudophakia; and visual acuity. Results Ninety patients were included, 40% had unilateral and 60% had bilateral cataracts. Follow-up was on average 51 months (range: 12–130 months). Strabismus was found preoperatively in 34.4% children, and in 43.3% children at last follow-up. Strabismus developed in 46.2% of children who were orthotropic preoperatively, whereas 32.3% of children who had strabismus before surgery became orthotropic. Strabismus occurred after unilateral or bilateral cataract surgery in 63.9% and 29.6% children, respectively. At the last follow-up, strabismus was found in 46.7% of aphakic and 58.7% of pseudophakic children (P=0.283). Children who developed strabismus were generally operated at a younger age as compared with those without strabismus (mean of 25.9 vs 52.7 months, Pstrabismus. Conclusion Strabismus is a frequent complication after cataract surgery in children. Risk factors include unilateral cases and young age at surgery. No correlation was found between prevalence of strabismus and use of intraocular lens. Strabismus was more common in children with poor final visual acuity. PMID:27472210

Cryptogenic organising pneumonia presenting with bilateral hilar and mediastinal lymphadenopathy.

Science.gov (United States)

Kahraman, Hasan; Tokur, Mahmut; Sayar, Hamide; Inci, Mehmet Fatih

2013-06-10

Cryptogenic organising pneumonia is not considered in the differential diagnosis of bilateral hilar and mediastinal lymphadenopathy. We submitted a patient presenting with bilateral hilar and mediastinal lymphadenopathy. We suspected diagnosis of sarcoidosis, but the patient was diagnosed as cryptogenic organising pneumonia with the histological result. This is the second case report of cryptogenic organising pneumonia presenting with bilateral hilar and mediastinal lymphadenopathy.

Incorrect position of Essure microinserts 3 months after successful bilateral placement.

Science.gov (United States)

Gerritse, Maria B E; Veersema, Sebastiaan; Timmermans, Anne; Brölmann, Hans A M

2009-03-01

To describe incorrect positions of Essure microinserts detected at 3 months' follow-up. Case report. Outpatient department of obstetrics and gynecology in a Dutch teaching hospital. Initial series of 100 patients who underwent hysteroscopic sterilization using Essure between December 2003 and June 2004. Hysteroscopic placement of the Essure System, follow-up at 3 months with transvaginal ultrasound (TVU), and hysterosalpingography. Bilateral placement rate, tubal obstruction, and detection of incorrect Essure microinsert localization at follow-up after apparent successful bilateral placement. Bilateral placement of Essure microinserts in one session was successful in 93 women (93%). In 90 of these women (96.8%), tubal obstruction was proven at follow-up 3 months later. Three incorrect positions of an Essure insert were seen: two expulsions and one perforation into the abdominal cavity. Incorrect position of Essure microinserts was seen only when the initial placement procedure was difficult. When a placement procedure was difficult or other suboptimal conditions are present during the procedure, we advise performing a TVU or pelvic X-ray in these women 4 weeks after the procedure or after the first vaginal bleeding, instead of waiting for follow-up after 3 months.

Luxatio erecta bilateral: um relato de caso Bilateral luxatio erecta, a case report

Directory of Open Access Journals (Sweden)

César Augusto Xavier Acosta

2012-02-01

Full Text Available O deslocamento inferior do ombro (luxatio erecta é uma lesão rara, acometendo aproximadamente 0,5% dos deslocamentos dessa articulação. A grande maioria desses casos ocorre unilateralmente. Em setembro de 2004, um homem de 43 anos chegou ao pronto-socorro do Hospital Universitário de Santa Maria (HUSM com queixa de dor bilateral no ombro e incapacidade de abaixar os braços, em consequência de uma queda com os braços abduzidos, enquanto desempenhava sua atividade laboral. Após o exame físico e radiológico constatou- se que o indivíduo apresentava uma luxação inferior bilateral dos ombros. O paciente foi então encaminhado ao bloco cirúrgico onde foi realizada redução incruenta das luxações sob anestesia através da técnica de tração e contra-tração. No dia seguinte recebeu alta com imobilização tipo Velpeau mantendo os ombros totalmente aduzidos e rotados internamente, com orientação de manter a imobilização por três semanas. Foi orientado também a realizar fisioterapia.Inferior shoulder dislocation (luxactio erecta is a rare lesion affecting approximately 0.5% of dislocations of this joint. The vast majority of these cases occur unilaterally. In September 2004, a 43 year old man was brought to the emergency room of the University Hospital of Santa Maria (HUSM complaining of bilateral shoulder pain and inability to lower the arms, as a result of a fall with the arms abducted, while carrying out work activities. After physical examination and radiological exams, it was found that the patient had a bilateral inferior shoulder dislocation. He was referred to the surgical ward and after intravenous sedation, both shoulders were reduced by closed reduction using the traction-countertraction maneuver. The patient was discharged the day after the reduction. Both arms were immobilized with a velpeau sling in total adduction and intrarotation, with instructions to maintain immobilization for three weeks. The patient was

Bilateral Herpes Simplex Uveitis: Review of the Literature and Own Reports‏.

Science.gov (United States)

de-la-Torre, Alejandra; Valdes-Camacho, Juanita; Foster, C Stephen

2017-08-01

Herpes simplex-associated uveitis is usually considered a unilateral eye disease, and rarely included in the differential diagnosis whenever there is bilateral involvement. We report three cases of bilateral herpetic anterior uveitis. We evaluated three patients who presented with clinical manifestations of bilateral uveitis suggestive of viral origin. We found intraocular hypertension, cells in the anterior chamber, paralytic mydriasis, iris atrophy with transillumination defects, and variable anterior vitreous cellularity. According to the clinical findings, supported with herpes-specific antibody titers and aqueous humor PCR results in two of them, they were diagnosed with bilateral anterior herpetic uveitis. Our patients were initially misdiagnosed as having non-infectious uveitis and were treated with immunomodulatory medications, which could have favored the extension of infection bilaterally. Although uncommon, bilateral herpetic uveitis should always be considered in the differential diagnoses, when patients present with hypertensive uveitis in both eyes.

Synchronous, bilateral tonsillar carcinomas

DEFF Research Database (Denmark)

Nami Saber, Camelia; Grønhøj, Christian; Jensen, David Hebbelstrup

2017-01-01

INTRODUCTION: The incidence of oropharyngeal squamous cell carcinoma (OPSCC) is increasing, but data on the incidence of synchronous, bilateral tonsillar squamous cell carcinomas (BiTSCCs) is sparse. In this study, we report the incidence and tumour characteristics of BiTSCCs in a population-base...

Bilateral acoustic neuromas.

Science.gov (United States)

Anand, V T; Byrnes, D P; Walby, A P; Kerr, A G

1993-10-01

This article reviews 12 patients with bilateral acoustic neuromas. The sex incidence was equal and the mean age at diagnosis was 26.2 years. The family history was positive in nine of the patients. Five patients have had incomplete surgical removal of acoustic neuromas on both sides. Two of them are completely deaf and the other three have severe sensorineural hearing loss in one ear and no hearing in the other ear. In five patients the tumour on one side has been operated on and the other side is being observed with at least short-term preservation of good hearing. The remaining two patients died of intra-cranial complications, one of them post-operatively. Four patients developed facial palsy immediately following surgery and one developed facial weakness 6 months after surgery. Guidelines are discussed for the care of these patients including the timing of surgery and alternative treatment options (observation, radio-surgery and chemotherapy). This is essentially a group of young individuals who have had multiple operations for bilateral acoustic tumours and associated manifestations and for whom the disease and the sequelae of treatment can be tragic.

Simultaneous bilateral contracture of the infraspinatus muscle.

Science.gov (United States)

Franch, J; Bertran, J; Remolins, G; Fontecha, P; Díaz-Bertrana, M C; Durall, I

2009-01-01

A case of bilateral fibrotic contracture of the infraspinatus muscles in a five-year-old Belgian Shepherd dog is described. The dog was presented with progressive forelimb lameness with postural and gait abnormalities three months after an episode of overexertion. When walking, the lower part of both forelimbs swung in a lateral arc causing a circumduction movement and in the standing position, the dog showed elbow adduction with external rotation of the distal part of both front limbs. Orthopaedic examination revealed bilateral atrophy of both infraspinatus and supraspinatus muscles and restriction in the range of motion of both shoulders, especially when attempting abduction and flexion. No specific findings were observed in the shoulder or elbow radiographs but hyperechogenic areas were evident in the ultrasonographic examination of both infraspinatus muscles. A diagnosis of fibrotic contracture of both infraspinatus muscles was established and bilateral tenectomy of the insertion tendons of the infraspinatus muscles was performed. Complete recovery of the animal was achieved after the surgery, which was confirmed in a long-term follow-up (10 months). In conclusion, physical examination and ultrasonography allowed a proper diagnosis of the condition, and tenectomy of the infraspinatus muscles resulted in a complete recovery of the patient even with bilateral involvement.

'Opening a can of worms': Bilateral varicoceles as an indicator of ...

African Journals Online (AJOL)

The scrotal varicocele is a common finding encountered during clinical examination. A porto-systemic shunt presenting with an associated varicocele is exceptionally rarely reported. Herein, we report such a case in an HIV positive man who presented with bilateral varicoceles. This is only the fifth case of such an ...

Bilateral ureteropelvic junction obstruction presenting with hypertension and cerebral vascular accident.

Science.gov (United States)

Tourchi, Ali; Kajbafzadeh, Abdolmohammad; Nejat, Farideh; Golmohammadi, Abolfazl; Alizadeh, Farshid; Mahboobi, Amir Hassan

2010-11-01

Cerebrovascular accident and renal hypertension secondary to ureteropelvic junction obstruction (UPJO) are extremely rare. A 6-year-old girl presented with intracranial hemorrhage because of hypertension secondary to the bilateral UPJO. This was successfully treated with craniotomy and subsequent percutaneous nephrostomy placement and bilateral pyeloplasty. Brain computerized tomography revealed right-sided intracranial hemorrhage, and renal ultrasonography confirmed bilateral severe hydronephrosis. Craniotomy with evacuation of intracerebral hematoma and bilateral nephrostomy under ultrasound guidance were performed. One week later, she underwent bilateral pyeloplasty in 2 stages. The patient has been well with normalized renal function and is completely cured of her hypertension in long-term follow-up. Copyright © 2010 Elsevier Inc. All rights reserved.

Bilateral Tubal Gestation Associated with Schistosomiasis in an African Woman

Directory of Open Access Journals (Sweden)

K. H. Odubamowo

2014-01-01

Full Text Available Background. The incidence of tubal ectopic gestation caused by schistosomiasis induced tubal pathology is undocumented in this environment, which may be due to rarity of this pathology. Bilateral tubal gestation is common in patients that have undergone in vitro fertilization. We report a hitherto undocumented case of spontaneous bilateral ectopic gestation following tubal schistosomiasis. Case Report. Mrs. OB was a 32-year-old G4P3+0 (3 alive woman who complained of abdominal pain and bleeding per vaginam of 4 and 2 days’ duration respectively following 8 weeks of amenorrhea. A clinical impression of ruptured ectopic gestation was confirmed by ultrasound scanning. She had bilateral salpingectomy with histology of specimens showing bilateral ectopic gestation with Schistosoma haematobium induced salpingitis (findings of Schistosoma haematobium ova noted on slide. Conclusion. Schistosoma induced salpingitis is a rare but possible cause of bilateral tubal gestation.

Bilateral and unilateral ECT: effects on verbal and nonverbal memory.

Science.gov (United States)

Squire, S R; Slater, P C

1978-11-01

The memory loss associated with bilateral and nondominant unilateral ECT was assessed with verbal memory tests known to be sensitive to left temporal lobe dysfunction and with nonverbal memory tests known to be sensitive to right temporal lobe dysfunction. Bilateral ECT markedly impaired delayed retention of verbal and nonverbal material. Right unilateral ECT impaired delayed retention of nonverbal material without measurably affecting retention of verbal material. Nonverbal memory was affected less by right unilateral ECT than by bilateral ECT. These findings, taken together with a consideration of the clinical efficacy of the two types of treatment, make what appears to be a conclusive case for unilateral over bilateral ECT.