Adaptive Fuzzy Sliding Mode Control for a Flexible Air-breathing Hypersonic Vehicle Based on Tracking Differentiator

摘要

This paper presents an adaptive fuzzy sliding mode controller for a flexible air-breathing hypersonic vehicle. First, the control-oriented model is decomposed into velocity and altitude subsystems. With the system transformation, the altitude subsystem is transformed into the normal cascade structure. A novel sliding mode control scheme is proposed which avoid the complicated recursive design procedure of backstepping. In the control scheme, the unknown nonlinear functions, adaptive fuzzy logic systems are designed to estimate them. Meanwhile, a tracking differentiator is used to estimate the newly generated states of the altitude subsystem. The sliding mode surfaces are proved to be asymptotically accessible and both velocity and altitude subsystems can converge to their command signals. Finally, simulation results are demonstrated to show the effectiveness of the presented control scheme.