Tracking Control of Serial Robot Manipulator using Active Disturbance Rejection Control

This paper introduces tracking control method for robot manipulator based on Active Disturbance Rejection Control technique (ADRC). The main purpose of the ADRC technique is to obtain a proper estimation, cancel the total disturbance along with the assurance of a good trajectory tracking. First, the equations of motion of the robot manipulator is rearranged to be suitable for the ADRC technique. Then, an extended model is derived from the dynamic model. This extended model has an extra state includes the total disturbances, which are estimated online through the extended state observer (ESO). Finally, this estimated disturbance is compensated through a simple PD feedback controller. This control strategy is tested on two-DOF serial link manipulator and compared by a simple PID controller. Simulation results show the advantage of the ADRC system over the PID controller.