L₁ adaptive control for automated aerial refueling

During the automated aerial refueling (AAR), when the receiver approaches to couple with a refueling drogue, the hose-drogue system undergoes a transient motion due to the receiver forebody aerodynamic effect, in addition to the tanker motion and downwash. Thus, the receiver requires an accurate flight control. For this purpose, we propose a novel adaptive controller on the basis of LQR proportional integral control for stabilizing the closed-loop, to realize the fast accurate refueling with desirable transient performance and the steady-state precision. Simulation results show that this method ensures the realization of an accurate AAR in a given finite time period by restraining the disturbance as well as reducing the model error, and meets the control requirements of AAR in both the transient and steady states.