Adaptive Failure Compensation of Actuators in Controlling Servo System Driven by Twin Motors

In this paper, an adaptive control scheme based on backstepping techniques is proposed for a class of servo systems driven by twin motors with unknown actuator failures. Unlike the existing results about fault tolerant control of such servo systems, the proposed adaptive control scheme can adjust the parameters' estimation automatically with the change of unknown parameters caused by unknown actuator failures. Since the parameters of control reconfiguration are updated directly by adaptive law, system performance can be improved significantly and the resulting controller structure is much simpler. In addition, the requirements on the upper bounds of matched and unmatched uncertainties are relaxed, namely, such bounds are no longer needed in the proposed control law. Finally, simulation results also demonstrate the effectiveness of the control scheme.