Adaptive fuzzy fault-tolerant control via integral terminal sliding mode of robotic systems with prescribed performance

This paper addresses the robust fault-tolerant tracking control problem of robotic systems with actuator faults and model uncertainties under prescribed performance constraint. Firstly, an adaptive technique and fuzzy logic system are used to approximate the system model uncertainties and possible actuator faults. Secondly, a new fast integral terminal sliding mode backstepping control method is proposed, which makes the high robustness for the robotic systems when the actuator faults occur under the premise of ensuring the prescribed performance. Furthermore, a nonlinear disturbance observer is developed to estimate the lumped disturbance composed of external disturbance and approximation error, which enhances anti-disturbance performance, reduces sliding mode chattering, and ensures high robustness of the entire robotic systems. Ultimately, the global asymptotic stability of the robotic systems is achieved based on the Lyapunov criterion. The simulation results confirm the effectiveness of the proposed control scheme.