关键词: 六旋翼无人机, 复合干扰, 指令滤波, 滑模观测器, 鲁棒控制

Abstract:

Aiming at the problem of robust control for a six rotor UAV with complex disturbances, a robust control method based on sliding mode observer is proposed. Firstly, the mathematical models of the position and attitude of the six rotor UAV are established, and the sliding mode control law is designed for the position loop to solve the attitude command. Then, according to the virtual control law of the attitude loop output, the command filter is designed to suppress the differential explosion phenomenon, and the auxiliary filter is used to compensate the error of the command filter. Finally, the sliding mode observer is introduced into the angular velocity loop robust control law to compensate the complex disturbance including model error and external disturbance, which realizes the command filtering robust control of the six rotor UAV. The simulation results show that the proposed robust control law has better stability, accuracy and rapidity than the adaptive control method, the maximum error of position and attitude is only 0.05 m and 0.5° respectively, and the estimation error of sliding mode observer is only 0.2 （°）/s, which realizes the robust control of displacement and attitude for six rotor UAV in a shorter time.

Key words: six-rotor UAV, compound disturbance, command filter, sliding mode observer, robust control