Abstract:Aiming at the attitude fault-tolerant control problem of launch vehicle with model uncertainty, external environment disturbance and actuator fault, an adaptive prescribed performance fault-tolerant control method is proposed. Firstly, based on the attitude motion model, actuator fault model and attitude tracking error model of the launch vehicle, the mathematical model of fault-tolerant control of the launch vehicle is established. Then, a cascade extended state observer is used to observe and compensate for total disturbances, and a fixed time convergent adaptive preset performance function is proposed to address the problem of sudden changes in attitude tracking errors caused by faults. A prescribed performance backstepping control law is designed, and the stability of the closed-loop control system is proved; Finally, through numerical simulation, it is verified that the control method can ensure that the attitude tracking error meets the prescribed performance index under the condition of actuator failure.