Adaptive Robust Tracking Control Based on Backstepping Method for Uncertain Robotic Manipulators Including Motor Dynamics

Recent research on the backstepping control of robotic systems has motivated us to design a robust backstepping voltage-based controller with computational simplicity and ease of implementation. In this paper, an adaptive robust tracking controller based on backstepping method (ARTB) is presented for uncertain electrically-driven robotic manipulators in the framework of voltage control strategy. It is intended to convert robot control problem to motor control problem. In the design procedure, the manipulator dynamics are incorporated into a lumped uncertainty, such that the proposed adaptation law promptly compensates for it. Hence, high tracking accuracy, robust behavior and less complexity are the prominent features of the proposed control system in the presence of external disturbances, parametric uncertainties and un-modeled dynamics. The stability of the closed-loop system is guaranteed based on the Lyapunov theory and the tracking error converges to zero asymptotically. As a case study, the proposed ARTB is simulated on a two-link robot manipulator driven by permanent magnet DC motors. Numerical simulations are included to show the superiority of the proposed controller to a state augmented adaptive backstepping method, a sliding backstepping controller and an adaptive backstepping sliding mode control in tracking the desired trajectory.