Proximate fixed-time fault-tolerant tracking control for robot manipulators with prescribed performance

This paper presents a proximate fixed-time fault-tolerant prescribed performance tracking control for robot manipulators with actuator faults, parametric uncertainties, and bounded disturbances. An exact convergent fixed-time prescribed performance function is first introduced. A proximate fixed-time fault-tolerant prescribed performance control (FTPPC) is proposed within the framework of terminal sliding mode control. Lyapunov stability is employed to prove the position tracking error can be ensured proximate fixed-time stability and prescribed performance with an exact convergence time. Advantages of the proposed FTPPC include proximate fixed-time prescribed performance guarantees featuring faster transient and higher steady-state precision and strong robustness to actuator faults, parametric uncertainties, and bounded disturbances. Simulations and experiments utilizing artificial faults demonstrate the improved performances of the proposed approach.