Tracking Control of RLFJ Robot Manipulator Using Only Position Measurements by Backstepping Method

Abstract

A tracking controller is presented for RLFJ(rigid link flexible joint) robot manipulators with only position measurements. The controller is developed based on the integrator backstepping design method and on the two observers: the first is simple linear form obsever for the filtered link velocity errors and the other for the actuator velocities. The proposed controller achieves exponential tracking of link positions and velocities while keeping all internal signals bounded. It also guarantees exponential convergence of the estimated signals to their actual ones. Finally, simulation results are included to demonstrate the tracking performance. 1 Introduction Trajectory tracking control of a robotic manipulator with joint flexibility has received considerable attention in recent years. Since mechanical torques are often applied to the robot links through gearing mechanisms, many researchers have included the effects of joint flexibility (e.g., shaft wind-up, bearing deformation, compre...