Adaptive augmentation of gain-scheduled controller for aerospace vehicles

This paper proposes an adaptive augmentation control design approach of the gain-scheduled controller. This extension is motivated by the need for augmentation of the baseline gain-scheduled controller. The proposed approach can be utilized to design flight control systems for advanced aerospace vehicles with a large parameter variation. The flight dynamics within the flight envelope is described by a switched nonlinear system, which is essentially a switched polytopic system with uncertainties. The flight control system consists of a baseline gain-scheduled controller and a model reference adaptive augmentation controller, while the latter can recover the nominal performance of the gain-scheduled controlled system under large uncertainties. By the multiple Lyapunov functions method, it is proved that the switched nonlinear system is uniformly ultimately bounded. To validate the effectiveness of the proposed approach, this approach is applied to a generic hypersonic vehicle, and the simulation results show that the system output tracks the command signal well even when large uncertainties exist.