Dynamic Feedforward Based Fractional Order Impedance Control for Robot Manipulator

Impedance control is an important method for robot manipulator to control the contact force. By expanding the traditional integer order impedance model to the fractional order model, a fractional order impedance (FO-impedance) controller is presented first in this paper. A FO-impedance controller parameters tunning strategy based on the frequency-domain is presented. A systematic FO-impedance control simulation system with robot manipulator, servo system, dynamic disturbance and dynamic feedforward is constructed. The influence of time-varying dynamic characteristics for robot FO-impedance system is analyzed. In order to achieve desired dynamic response and high robustness performance, a dynamic feedforward method is proposed and the effectiveness is verified in the simulation.