54 research outputs found

    Haptic teleoperation under variable delay and actuator saturation

    Full text link

    Multi-Finger Haptic Devices Integrating Miniature Short-Stroke Actuators

    Get PDF
    The omnipresence of electronic devices in our everyday life goes together with a trend that makes us always more immersed during their utilization. By immersion, we mean that during the development of a new product, it is more and more required to stimulate several senses of the user so as to make the product more attractive. The sense of touch does not escape the rule and is more and more considered. Definitely democratized by its integration in smart phones with touchscreens, the haptic feedback allows enhancing the human-machine interactions in many ways. For instance by improving the comfort of use of a button through the modification of its force feedback. It can also offer an interactive experience during the manipulation of digital information and even improve the communication, particularly through the internet and for blind people, with the introduction of non-verbal signals. For these reasons, the present thesis focuses on the conception of multi-finger haptic devices, a new kind of peripherals integrating multiple actuators and capable of providing a fully programmable force feedback to the user's fingers. A global methodology is presented, outlining the different constituents necessary for their conception: actuator, sensor, control, communication and software user interface. Then, generic tools corresponding to the two first elements are presented. An accurate modeling of miniature electromagnetic short-stroke actuators is made possible thanks to the combination of 3D finite element modeling (FEM) and design of experiments (DOE). The non-usual behavior of magnetic flux lines in miniature actuators with relatively large airgaps imposes to avoid simplified analytical models and to use the reliable results of finite elements. The long computation times required by 3D FEM are balanced by the use of selective DOE making the modeling methodology easily adaptable, rapid and accurate. The parametrical model of the force provided by the modeling methodology is then integrated in a full parametrical setup allowing for the optimization of the actuator force using a conventional algorithm. The advantage of the parametrical optimization is that complementary non-linear constraints such as weight and temperature can be added, making the model multi-physic. Then, several original position measurement techniques using existing sensors are developed including a low-cost custom single-photointerrupter sensor allowing for direction discrimination for fast-prototyping and a hybrid sensing method using tiny Hall sensors and taking advantage of the leaks of the main actuator magnet. Two innovative self-sensing methods are then presented, allowing for the measurement of the mover position of linear short-stroke actuators. The first solution estimates the position of the coil by measuring the acceleration through the back emf. However in this case, a constant acceleration is required, which strongly restrains the application scope. The second solution allows for a real-time measurement of the position thanks to a passive oscillating RLC circuit influenced by the variation of the coil impedance. All the solutions presented are low-cost, compact and require few computation resources. Finally, in order to illustrate the methodology proposed along the thesis, several prototypes are fabricated, giving an overview of the possibilities offered by multi-finger haptic devices. A haptic numeric pad is notably used in an experiment made in collaboration with the University Service of Child and Adolescent Psychiatry in Lausanne with the aim of improving the impaired emotional processing of psychotic adolescents. Moreover, the successful identification of several touch sensations on the same haptic pad lays the first stones of a new tactile language

    Proceedings of the NASA Conference on Space Telerobotics, volume 2

    Get PDF
    These proceedings contain papers presented at the NASA Conference on Space Telerobotics held in Pasadena, January 31 to February 2, 1989. The theme of the Conference was man-machine collaboration in space. The Conference provided a forum for researchers and engineers to exchange ideas on the research and development required for application of telerobotics technology to the space systems planned for the 1990s and beyond. The Conference: (1) provided a view of current NASA telerobotic research and development; (2) stimulated technical exchange on man-machine systems, manipulator control, machine sensing, machine intelligence, concurrent computation, and system architectures; and (3) identified important unsolved problems of current interest which can be dealt with by future research

    Technology for large space systems: A bibliography with indexes (supplement 20)

    Get PDF
    This bibliography lists 694 reports, articles, and other documents introduced into the NASA Scientific and Technical Information System between July, 1988 and December, 1988. Its purpose is to provide helpful information to the researcher or manager engaged in the development of technologies related to large space systems. Subject areas include mission and program definition, design techniques, structural and thermal analysis, structural dynamics and control systems, electronics, advanced materials, assembly concepts, and propulsion

    Technology 2000, volume 1

    Get PDF
    The purpose of the conference was to increase awareness of existing NASA developed technologies that are available for immediate use in the development of new products and processes, and to lay the groundwork for the effective utilization of emerging technologies. There were sessions on the following: Computer technology and software engineering; Human factors engineering and life sciences; Information and data management; Material sciences; Manufacturing and fabrication technology; Power, energy, and control systems; Robotics; Sensors and measurement technology; Artificial intelligence; Environmental technology; Optics and communications; and Superconductivity

    ISMCR 1994: Topical Workshop on Virtual Reality. Proceedings of the Fourth International Symposium on Measurement and Control in Robotics

    Get PDF
    This symposium on measurement and control in robotics included sessions on: (1) rendering, including tactile perception and applied virtual reality; (2) applications in simulated medical procedures and telerobotics; (3) tracking sensors in a virtual environment; (4) displays for virtual reality applications; (5) sensory feedback including a virtual environment application with partial gravity simulation; and (6) applications in education, entertainment, technical writing, and animation

    Large space structures and systems in the space station era: A bibliography with indexes

    Get PDF
    Bibliographies and abstracts are listed for 1219 reports, articles, and other documents introduced into the NASA scientific and technical information system between July 1, 1990 and December 31, 1990. The purpose is to provide helpful information to the researcher, manager, and designer in technology development and mission design according to system, interactive analysis and design, structural and thermal analysis and design, structural concepts and control systems, electronics, advanced materials, assembly concepts, propulsion, and solar power satellite systems

    Technology for large space systems: A bibliography with indexes (supplement 16)

    Get PDF
    This bibliography lists 673 reports, articles and other documents introduced into the NASA scientific and technical information system between July 1, 1986 and December 31, 1986. Its purpose is to provide helpful information to the researcher, manager, and designer in technology development and mission design according to system interactive analysis and design, structural and thermal analysis and design, structural concepts and control systems, electronics, advanced materials, assembly concepts, propulsion, and solar power satellite systems
    corecore