Based on the analyze of the assist walking exoskeleton leg behavior characteristics, the total cource locomotion can be divided into swing and stance two phase. To the stance phase, the position control based on fixed gravity compensation is used. To the swing phase, the fast terminal sliding mode control is used to design the virtual torque controller. Theoretical analyse and simulation results test the feasibility and validity of this control method.

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The required tasks in fixed-base exoskeletons demand a fast position/force controller; yet robust against unknown disturbances due to the application itself is tightly coupled with a human in a wide range of operational conditions, which give rise to human-exoskeleton interaction dynamics, high nonlinear uncertain exoskeleton dynamics, noisy sensors and other parametric uncertainties, such as environmental contacts. These factors do not allow to account on a precise dynamical model, thus model-based (regressor-based) controllers are difficult to implement. This paper deals with a regressor-free smooth PID-like fast force/position controller which guarantees finite-time convergence within second order sliding modes, thus ensuring inherent robustness. Experimental platform allows assessing its performance for rehabilitation tasks, which validates its functionality in practical implementation.

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Common actuators have important drawbacks for use in an exoskeleton type of rehabilitation (training) robot. Either the actuators are heavy, complex or poor torque sources. A new actuation system is proposed and tested that combines a lightweight joint and a simple structure with adequate torque source quality. It consists of a servomotor, a flexible Bowden cable transmission, and a force feedback loop based on a series elastic element. Measurements show that performance is sufficient for use in a gait rehabilitation robot.

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This paper presents HANDEXOS, a novel wearable multiphalanges device for post-stroke rehabilitation. It was designed in order to allow for a functional and safe interaction with the user’s hand by means of an anthropomorphic kinematics and the minimization of the human/exoskeleton rotational axes misalignment. This paper describes the mechatronic design of the exoskeleton’s index finger module, simulation, modeling, and development of the actuation unit and sensory system. Experimental results on the validation of the dynamic model and experimental characterization of the index finger module with healthy subjects are reported, showing promising results that encourage further clinical trials.

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For supporting daily activities of elderly and physically disabled people who have lost their body functioning of motions, we have developed a 7-DOF robotic exoskeleton system. It is intended to assist the motions of shoulder and elbow by mounting this on a wheel chair since human shoulder and elbow motions are involved in a lot of activities of everyday life. The proposed mechanism can maximize workspace while escaping singularity by combining the parallel mechanism at the wrist part. Admittance based velocity control scheme enables a variety of tasks to be implemented and allows us to achieve fast enough motion with acceptable accuracy. Preliminary results for mechanism analysis, trajectory tracking experiment are shown.

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