Abstract:Aiming at the problems of boring contents of traditional wrist rehabilitation training methods and low training efficiency due to users lack of motivation to participate,a wrist training system of myoelectric control virtual reality game was designed.The surface electromyography (sEMG) signals of wrist movement were collected and the wrist joint movement intention was decoded through the principle of muscle synergy for the control of the virtual reality game;random disturbance force was introduced into the virtual reality game,and the interaction with the virtual reality environment was realized through the way of impedance control,which enabled users to explore different movement control methods.The feasibility of the system was verified through model calibration experiments,and training experiments were conducted to assess the training effect by evaluating the task completion time as well as the path efficiency.The experimental results show that introducing random interference force reduces the task completion time by 24％ and improves the path efficiency by 26％,and the designed training system enables users to perform motion control in a more efficient way and improves the training efficiency.

Abstract:In this paper,an impedance composite control method based on disturbance observer is proposed for manipulator system with unknown disturbances.For tracking the second order impedance dynamic model,a composite control strategy is designed,which includes the disturbance observer (DOB),the impedance controller,and the position controller to estimate unknown disturbances,correct input angle,and track the adjusted angle,respectively.This composite control strategy ensures that the impedance error converges to a small neighborhood,thus realizes the desired dynamic tracking of the second order impedance model.The effectiveness of the proposed control method is proved by simulation examples.