Hand injuries are a frequent problem. The great amount of hand injuries is not only a problem for the affected people but economic consequences follow because rehabilitation takes a long time. Physical therapy after an operation is associated with high personnel expenses. To improve therapy results and reduce cost of rehabilitation a hand exoskeleton was developed. The handexoskeleton was specifically designed to accomplish requirements of medical applications. For research on control algorithms and rehabilitation programs a prototype supporting all four degrees of freedom of one finger was build. The device can be easily attached and also be adjusted to deformed and scarred hands. In view of the fact that a lot of hand injuries affect only one finger, this prototype could already be functional in physical therapy. This paper presents the construction and the control system of the hand exoskeleton and possible applications in therapy of hand injuries. For the position control a PID controller was implemented and evaluated. The resulting control system allows following of recorded trajectories with sufficient accuracy.

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This paper deals with the development of a novel exoskeleton for the robotic rehabilitation of upper extremities. The system is based on modular custom-designed actuation groups implementing high reduction ratios and redundant position measurement for securing patient safety, and joint torque sensing for guaranteeing system performance and providing application flexibility. Experimental results of the special component prototypes are reported which confirm the validity of the developed actuation groups and the potentials of the proposed exoskeleton architecture.

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EXOSTATION is a project aiming at building a complete haptic control station, which allows the operator wearing an exoskeleton-based haptic interface for the human to remotely control a virtual slave robot. The video presents the results achieved with the final system. It is composed of four main components. A human-arm exoskeleton used as a master haptic interface, its controller, a simulated virtual slave robot and a visualization tool. Demonstration scenarios are presented in the video and show the capabilities of the system.

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In this paper it is shown how variation of the kinematic structure of an exoskeleton and variation of its fixation strength on the human limb influences objective task performance metrics, such as interface load, tracking error and voluntary range of motion in a signal tracking experiment.

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One of the key features of upper limb exoskeletons is their ability to take advantage of the human arm kinematic redundancy in order to modify the subject’s joint dynamics without affecting his/her hand motion. This is of particular interest in the field of neurorehabilitation, when an exoskeleton is used to interact with a patient who suffers from joint motions desynchronization, resulting e.g. from brain damage following a stroke. In this paper, we investigate this problem from the robot control point of view. A first general controller is derived which uses viscous force fields in order to generate joint torques counteracting any velocities that are perpendicular to a given set of constraints. In order to minimize energy dissipation, a second controller is proposed that still uses viscous force fields, but in a way that the mechanical power dissipated by the viscous control is null at any time. This controller does not impose any trajectory to the hand and the robot only moves in response to the forces generated by the patient. This approach is experimented on a 4-DOF exoskeleton with a healthy subject. Results exhibit the basic properties of the controller and show its capacity to impose an arbitrary chosen joint constrain for 3-DOF pointing tasks without constraining the hand motion.

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