Fault Accommodation for near Space Hypersonic Vehicle with Actuator Fault

Based on fuzzy control and sliding mode observer technique, a fault accommodation strategy is proposed for near space hypersonic vehicle (NSHV) with actuator fault in this study. Firstly, the Takagi-Sugeno (T-S) fuzzy model is implemented to represent the NSHV nonlinear dynamics, and a bank of sliding mode observers are designed for the established T-S model, which are used to generate the residuals. Then, a novel fault diagnostic algorithm is given to estimate the actuator fault occurred in NSHV dynamics. Utilizing the on-line obtained fault estimation information, a fault accommodation scheme is developed to compensate for the effects of actuator fault. Based on Lyapunov stability theory, a sufficient condition to guarantee the stability of faulty system is derived in terms of linear matrix inequalities (LMIs), which can be easily solved by Matlab LMI toolbox. Finally, simulation results are presented to demonstrate the efficiency of the proposed approach.