Novel Anti-Disturbance Trajectory Tracking Controller for UAV Autonomous Aerial Refueling Docking

This paper proposes an anti-disturbance trajectory tracking control scheme for the receiver in Autonomous Aerial Refueling (AAR) process based on a novel reference observer (ROB) and a high-order disturbance observer (HODO). The designed ROB in this paper could transform the reference output of receiver into reference states and inputs exactly under external disturbances. Moreover, the HODO could estimate the external disturbances such as wind perturbations suffered by receiver precisely. Combining these two observers, the ROB uses the disturbances estimated by HODO to obtain the exact reference states which could be used as inputs of a Linear Quadratic Regulator (LQR) based state-feedback controller and reference inputs which could be used as feedforward control inputs. Comparative simulation results show that the proposed control scheme achieves better performance in AAR docking control under complex flow perturbations.