Robust Adaptive Control of Hypersonic Vehicle Considering Inlet Unstart

A large-scale change in the aerodynamic characteristics of the aircraft caused by the inlet unstart of the air-breathing hypersonic vehicle causes a large oscillation of the response or even a control system instability. A model reference adaptive control method considering the influence of inlet unstart is proposed. Firstly, the attitude control system is designed based on LQR-PI method for the model of inlet start, which is used as the reference model. When the inlet unstart, the model reference adaptive control is added on the basis of LQR-PI controller to improve the robustness of the system to the uncertainties caused by the inlet unstart. The method can quickly stabilize the attitude when the inlet unstart, and provides conditions for the inlet restart. Finally, the present method is verified by the simulation results. The simulation results show that when the inlet unstart, the system can re-track quickly the control command, and the steady-state error tends to zero, which verifies the effectiveness of the present method.