Adaptive Robust Fault-Tolerant Regulation of Mechatronic Systems with Prescribed-Time Convergence

Abstract

In this paper, we propose a synchronized prescribed-time control strategy for a class of nonlinear mechatronic systems with external disturbance, actuation saturation, and actuator faults, which features simultaneous translational and rotational motion tracking in the same prescribed time. Dual quaternion is employed to model the coupling effect between translational and rotational motions, which provides a unified representation for describing multiple degree-of-freedom motions. In addition, online adaptive technology is incorporated for real-time monitoring and separation of actuator failure information. The adaptive capability of the controller to parameter perturbation, disturbance, and fault deviation is therefore enhanced. Furthermore, the closed-loop system is featured by L2 gain stability/robustness against thrust output deviation, while the system trajectory is guaranteed to converge with user-defined settling time. Finally, numerical simulations on a microsatellite platform with redundant thrusters are performed to verify the effectiveness of the proposed fault-tolerant control approach.