Decoupling of failed actuators in flight control systems

In this paper, an approach for predesigning controllers for a switching control scheme for systems undergoing actuator failures is proposed. Controller predesign for actuator failures is not trivial as the values at which the failed actuators freeze is not known a priori. The actuators failed at a nonzero position act as persistent disturbances significantly altering the system dynamics. The controller design in this paper is accomplished by using disturbance decoupling approach which ensures complete rejection of the disturbances caused by actuator failures in the steady state. The design is completed using linear quadratic control to address the transient response. The design procedure is demonstrated on a multiple actuator failure of an aircraft carrier landing system.