Virtual decomposition control of a 3 DOFs exoskeleton robot for space teleoperation

Abstract

This paper aims at realizing high precision control of a 3 degrees of freedom (DOFs) exoskeleton robot for space teleoperation, using virtual decomposition control (VDC), while strictly ensuring global stability. Based on the VDC approach, firstly, the entire system is virtually decomposed into several subsystems. Secondly, kinematics and dynamics of each subsystem are analyzed and the control equations are also obtained. Then, all of the subsystem controllers constitute the controller of the entire exoskeleton robot system. The combination of this controller and the robot system is the virtual decomposition system of this robot. Finally, the virtual decomposition system of the robot is simulated in a MATLAB/Simulink-based platform, compared with a control system using PID controller. The simulation results show that the virtual decomposition controller is effective and does much better than the PID controller under nonlinear conditions.