A Fault-Tolerant Control Scheme for Civil Aircraft Based on Prescribed Performance Control

In this paper, a fault-tolerant control scheme based on prescribed performance control is proposed to solve the pitch angle attitude control problem of large civil aircraft when actuator faults and external disturbances exist simultaneously. Firstly, the longitudinal motion model of civil aircraft with actuator fault is established. Among them, actuator faults and external disturbances are regarded as lumped disturbances. Then, a performance envelope is constructed based on the hyperbolic cosecant function which can adjust the transient convergence rate and the steady convergence rate respectively. In order to achieve fast online estimation of lumped disturbances, an RBF neural network observer is constructed. The introduction of tracking differentiator solves the problems of initial state constraint of prescribed performance control and “differential-explosion” in back-stepping control. After proving the stability of the system from the perspective of theoretical analysis, the simulation of pitch angle control under the condition of abrupt actuator faults and external disturbance is completed based on Boeing 747 longitudinal motion model.