Trajectory Tracking Control of Tilt-Wing eVTOL Using Aerodynamic Coupling Observer and Wing Angle Correction Method

Recently, electric vertical take-off and landing has been attracting attention as a potential solution for alleviation of urban traffic congestion, alternative tools of delivery, and inspection missions in disaster situations. We focus on the advantages of the tilt-wing type, such as the low drag of the wing during ascent and the ability to use the propeller wake even during transition phase to control the lift by flap. This paper focuses on the how to determine the tilt angle reference to track the desired trajectory. Some previous research uses the tilt angle that achieve trim state as the reference. It has a disadvantage that the actuator in the inner layer saturates when the high acceleration command is given or when wind disturbance exists. Proposed wing angle correction method enables aircraft to track the trajectory even in those situations by correcting the tilt angle to solve a optimization problem that considers the actuator input and disturbance estimated by the inner layer DOB. The results of the numerical simulation and hardware in the loop simulation show that the proposed control system reduces the actuator saturation and improves the trajectory tracking performance.