Adaptive Fixed-Time Fault-Tolerant Control for Space Manipulator with Prescribed Performance

The adaptive fixed-time fault-tolerant tracking control is investigated based on prescribed performance for a space manipulator, considering bounded external disturbances, parametric uncertainties, and input saturation. An enhanced prescribed performance function (PPF) is designed to feature faster transient. Subsequently, an adaptive fixed-time fault-tolerant prescribed performance tracking control (AFTPPC) strategy is presented within the framework of nonsingular terminal sliding mode control (NTSMC). Furthermore, an adaptive control law is developed to deal with external disturbances and parametric uncertainties. A rigorous theoretical analysis of practical fixed-time stability and the realization of prescribed performance is established using Lyapunov theory. Finally, simulations on a space manipulator example are conducted to validate the effectiveness and enhanced performance of the proposed controller.