Fault tolerant robust flight control using surface actuator hinge moments

A robust, flight control law is investigated to provide fault tolerance for air vehicles experiencing inertial state measurement sensor degradation. The method is particularly useful on low cost, precision weapons pursuing dynamic targets. Observation techniques are facilitated by representing the surface actuator aerodynamic induced hinge moment by a function that is Lipschitz within the actuator sweep angle. A stable output feedback flight control law, requiring only actuator angular position and current measurements, is designed to handle the hinge moment effects and track a predetermined angle-of-attack reference trajectory. Benefits include improved effectiveness, improved reliability without additional hardware, and a cost and weight savings. Simulations are conducted on a tactical missile interceptor to evaluate the controller at various operating conditions in the flight envelope.