Model-based fuzzy variable impedance sliding-mode control for trajectory tracking in physical human-robot interaction

This paper mainly presents a nonlinear fuzzy variable impedance sliding-mode controller. The controller provides asymptotic tracking for the robot end-effector in Cartesian coordinates applicable to human-robot interaction. Firstly, the forward and analytical inverse kinematics for a 7-DOF redundant manipulator were proposed. The optimal analytical inverse kinematic solution used redundant angle is chosen according to the joint angle minimum increment. Secondly, the controller based on dynamics model of the physical human-robot interaction was designed. Finally, using simulations with Matlab software, the effectiveness of the proposed controller is investigated.