Fuzzy reliable tracking control for flexible air-breathing hypersonic vehicles

In this paper, we present a fuzzy reliable tracking control design method for flexible air-breathing hypersonic vehicles (FAHVs) subject to disturbances and possible sensor/actuator failures. This problem is challenging due to the strong coupling effects, variable operating conditions and possible failures in FAHVs. First, Takagi-Sugeno (T-S) fuzzy model is used to represent the longitudinal dynamics model of FAHVs. Then, by considering the disturbances and the faults, the fuzzy reliable tracking problem is proposed, and the tracking control problem is transformed into a stabilization problem. A fuzzy reliable state-feedback controller is designed to guarantee the asymptotic stability of the closed-system. By the Lyapunov approach, the existence conditions for such a controller are established in terms of linear matrix inequalities. With the designed controllers, the reference command can be tracked in spite of actuator/sensor faults. Simulation has demonstrated the proposed design scheme.