Lateral Control Reconfiguration of Tailless Flying-wing UAV Based on L1 Adaptive Control Method

In traditional active control reconfiguration methods, fault type and location information are strongly relied on. It is time-consuming to design a variety of control laws for each type of fault which need to be taken into account. In order to overcome these disadvantages, a new method for flying-wing UAV lateral control reconfiguration based on L1 adaptive control method is proposed. The presented method considers the control surface failure as modeling error and disturbance. The L1 control method can also effectively restrains the high frequency signal in the control signal while guaranteeing adaptive speed. The two split drag rudders (SDRs) are applied to eliminate the sideslip of flying wing aircrafts by symmetrical deflections. Hence, the SDRs are crucial for the safety of flying-wing aircraft. In this paper, the control surfaces of SDR in this paper can deflect asymmetrically, and all lateral control surfaces can deflect simultaneously to make the aircraft roll and yaw.. In this way, dependence of flying-wing aircraft on SDR can be reduced. At the end of this paper, we verified the performance of the designed control reconfiguration method in the event of SDR failure. The simulation results showed that the designed controller can maintain an ideal command tracking effect under the condition of SDR damage, loose floating or stuck failure. The rapid adaptability and robustness are also satisfactory. The impact of SDR failure on flight safety is greatly reduced.