Design of vector flight controller for tiltable land-air cross-domain platform

By fusing a reliable pitch control mechanism and vector control algorithms, the hovering and wind-resistant flight characteristics of the land-air cross-domain platform can be significantly enhanced. Therefore, by introducing the freedom of lateral deflection to the land-air vehicle equipped with the duct-rotor quadrotor, this paper aims at achieving more diverse motion modes for such platform. The motion decoupling characterization is studied first, and the optimal thrust-to-weight ratio and tilt angle in side flight are determined to be 2 and 0°-30°, respectively. Based on such conclusion, the conventional quadrotor controller was applied and flight experiments at different tilting angles were carried out. The results show that with the increase of tilting angle, the error of this controller is getting larger, and the root mean square error and fluctuation of the roll angle can reach up to 17.19° and 66.96°, respectively. Then the decoupling controller design and simulation verification are carried out. The results show that the platform significantly reduces the roll angle amplitude during hovering, forward flight and side flight under wind load. The proposed controller could be applied to further improve the performance and application of such a tiltable land-air cross-domain platform.