Adaptive dynamic surface control of non-minimum phase hypersonic vehicles

For the longitudinal model of an air-breathing hypersonic vehicle, its pitch dynamics is characterized by nonminimum phase when the term “elevator to lift” is not negligible. Nonminimum-phase characteristic is one of the main challenges for control design. In this paper, the control design problem is investigated for this kind of hypersonic vehicle with uncertain parameters and a novel design philosophy is presented based on analysis of the plant´s dynamics. Firstly, this model is separated as velocity subsystem and pitch dynamics subsystem. For the former, an adaptive dynamic inversion controller is derived. For the latter, a high-gain adaptive dynamic surface controller is derived. Furthermore, the stability analysis represents the states and tracking errors are ultimately uniformly boundary. Finally, simulation results validate the proposed method.