Abstract:To address the problems of actuator faults, composite disturbances, and time-constrained convergence encountered during wing deformation of morphing aircraft, a prescribed performance sliding mode fault-tolerant tracking control method was proposed. A longitudinal nonlinear model and fault model of the morphing aircraft were established, which were decoupled into attitude and velocity subsystems to simplify controller design. Improved nonlinear disturbance observers were introduced to accurately estimate and compensate for actuator faults and composite disturbances in real time. Prescribed performance sliding mode fault-tolerant controllers were designed to ensure that tracking errors converge to a prescribed precision range within prescribed time, completely independent of initial states, thereby guaranteeing both transient and steady-state performance while maintaining flight safety. The uniformly ultimately bounded stability of the system and prescribed time convergence of tracking errors were rigorously proved via Lyapunov function. Simulation results validate the effectiveness, robustness, and fault-tolerant performance of the proposed method.