Extended state observer-based fixed-time fault-tolerant attitude control for hypersonic reentry vehicle

This paper investigates a fixed-time fault-tolerant control scheme for attitude tracking problem of hypersonic reentry vehicle subject to actuator faults. By using feedback linearization technique, a control-oriented model with actuator faults is established. Then a fixed-time extended state observer is proposed to estimate the lumped disturbances, including actuator faults, uncertainties and external disturbances. Based on the proposed observer and nonsingular terminal sliding mode technology, a novel fixed-time fault-tolerant controller is designed. The stability analysis indicates that the convergence time of the closed-loop system is bounded and independent of the initial states. Finally, simulation results demonstrate the effectiveness of the proposed control scheme.