An anti-windup fault tolerant control method for tailless flying wing aircraft

摘要

In this paper, the design of a constrained adaptive backstepping flight control law is discussed for a flying wing aircraft with actuator stuckness or failures, saturation nonlinearity of actuators considered. Faults of actuators are handled by online update laws which can estimate the fault parameters, thus reducing the effect of faults on control accuracy. Second-order low-pass command filters are introduced to limit the deflection angles of elevators and throttle levels, therefore avoiding saturation of actuators and the complex derivative computation in the backstepping process. In addition, control allocation strategy is designed to reduce the effect of faults on the lateral motion. The stability of the closed-loop system and the convergence of parameters are proved. Computer simulation shows that the closed-loop system is stable, the control law tracks reference trajectories well, and the actuators are within their physical limits in the presence of actuator faults.