Robust adaptive dynamic programming for morphing air-breathing hypersonic vehicles under unmatched uncertainty

This article investigates the robust control problem for morphing air-breathing hypersonic vehicles (MAHVs) considering partially unknown dynamics and aerodynamics/structure/control coupling. Different from existing robust control methods, this study introduces an appropriate utility function to formulate an equivalent optimal control problem, which is then solved using the adaptive dynamic programming algorithm to learn the robust control law. In particular, the additional force and moment caused by structural change and the coupling of aerodynamics/structure/control are accounted for. Furthermore, we present a rigorous theoretical proof for stability and convergence using the Lyapunov direct method. Additionally, it is shown that the MAHV is uniformly ultimately bounded under unmatched uncertainty. Finally, the performance is demonstrated using an MAHV system.