Force feedback from the virtual world can greatly enhance the sense of immersion even for simple applications. The ISU force reflecting exoskeleton enables the user to interact dynamically with simulated environments by providing an electromagnetic haptic interface between the human and the environment. The paper describes the high bandwidth electromagnetic haptic interface and how it has been used to provide the sense of contact in the synthetic environment. The air gap between the magnetics, carried by the robot, and the coils attached to the human’s digits, allows for small relative motion between the human and the robot without affecting the transmission of forces. This flexibility allows the robot to track the human as well as develop appropriate forces from the virtual world. Three different typical synthetic environments are programmed and tested using the ISU force reflecting exoskeleton haptic interface device. The experimental results shows that the magnetic interface gives adequate force levels for perception of virtual objects, enhancing the feeling of immersion in the virtual environment

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An exoskeleton haptic interface is developed for functional training in virtual environments. A composite control scheme enables a variety of tasks to be implemented, and a ¿Qt¿ graphics library is used to generate the virtual environment for the haptic interface at the hand and graphical user interfaces for input and telemetry. Inter-process communications convert telemetry from the exoskeleton into motion commands for objects in the virtual environment. A second haptic interface at the upper arm is used to control the elbow orbit self-motion of the arm during tasks. Preliminary results are reviewed for a wall-painting task in which the virtual wall stiffness and viscosity are generated using an admittance controller.

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The evolution of an arm exoskeleton design for treating shoulder pathology is examined. Tradeoffs between various kinematics configurations are explored, and a device with five active degrees of freedom is proposed. Two rapid-prototype designs were built and fitted to several subjects to verify the kinematic design and determine passive link adjustments. Control modes are developed for exercise therapy and functional rehabilitation, and a distributed software architecture that incorporates computer safety monitoring is described. Although intended primarily for therapy, the exoskeleton is also used to monitor progress in strength, range of motion, and functional task performance

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This paper introduces a novel type of actuator that is investigated by ESA for force-reflection to a wearable exoskeleton. The actuator consists of a DC motor that is relocated from the joint by means of Bowden cable transmissions. The actuator shall support the development of truly ergonomic and compact wearable man-machine interfaces. Important Bowden cable transmission characteristics are discussed, which dictate a specific hardware design for such an actuator. A first prototype is shown, which was used to analyze these basic characteristics of the transmissions and to proof the overall actuation concept. A second, improved prototype is introduced, which is currently used to investigate the achievable performance as a master actuator in a master-slave control with force-feedback. Initial experimental results are presented, which show good actuator performance in a 4 channel control scheme with a slave joint. The actuator features low movement resistance in free motion and can reflect high torques during hard contact situations. High contact stability can be achieved. The actuator seems therefore well suited to be implemented into the ESA exoskeleton for space-robotic telemanipulation

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Exoskeletons are expected to be used as wearable haptic devices and power assist robot systems. We have been studyingexoskeletons to assist the human motion in daily activity and rehabilitation. The EMG (electromyogram), which directly reflects the human motion intention, has been used to control the exoskeleton without any special control equipment. This paper presents a strategy that realizes the effective adaptation of the EMG-based exoskeleton controller (i.e., robot-human interface) to any persons.

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