Barrier Function-based Adaptive Super Twisting Active Fault Tolerant Control for Robotic Manipulators with Actuator Faults

This paper investigates the issue of active fault tolerant control (AFTC) for manipulator with actuator faults. First, a higher-order sliding mode (HOSM) observer for fault diagnosis is constructed to estimate unmeasured states and compensate for the actuator faults simultaneously. Then, a feedback fault tolerant control (FTC) strategy is proposed to guarantee system's convergence in finite time and to reduce chattering phenomena based on the nonsingular fast terminal sliding mode (NFTSM) and barrier function-based adaptive super twisting (BFAST) algorithm. The finite time stability of the proposed FTC scheme is demonstrated by Lyapunov theory. Finally, simulations are performed to demonstrate the effectiveness of the proposed control method.