基于LADRC扩张滑模控制的四旋翼无人机的控制方法稳定性研究

Research on the Stability of the Control Method of the Quadrotor UAV Based on LADRC Extended Sliding Mode Control

针对四旋翼无人机在飞行过程中存在外部干扰问题以及在仿真过程中会出现抖动和仿真结果不收敛的问题,提出了串级LADRC-LESO滑模控制方法,来使四旋翼无人机在飞行过程中趋于稳定并具有一定的抗干扰效果。为了更好的提高四旋翼无人机的抗干扰性和稳定性,分别设计了姿态控制器和位置控制器,使四旋翼无人机在飞行过程中的抗干扰能力更强。通过在位置控制器中X通道设计线性扩张观测器(LESO)滑模控制器,在Y、Z通道放置了PID控制器,在姿态控制器中的俯仰、滚转和偏航3个通道中设计线性扩张观测器(LESO)滑模控制器来保证了姿态角所受到的总干扰影响较小,使四旋翼无人机在飞行中的稳定性有所提高。为了验证该方法的稳定性与抗干扰性更好,将其与已有的ADRC控制算法和LADRC控制算法进行对比仿真,得出该方法的稳定性与抗干扰效果更明显。

A cascade LADRC-LESO sliding mode control method is proposed to solve the problem of external interference in the flight process of the quadrotor UAV and the problem of jitter and non-convergence of the simulation results in the simulation process.The quadrotor UAV tends to be stable during flight and has a specific anti-interference effect.To better improve the anti-interference and stability of the four-rotor UAV,the attitude controller and the position controller are designed respectively,and they are combined with the LADRC control algorithm and the sliding mode control algorithm to make the four-rotor UAV have more vital anti-interference ability during flight.By designing a linear extended observer(LESO)sliding mode controller in the X channel of the position controller,a PID controller is placed in the Y and Z channels so that the position can be stably tracked.At the same time,in the attitude controller,a linear extended observer(LESO)sliding mode controller is also designed in the three channels of pitch,roll and yaw to ensure that the total disturbance impact on the attitude angle is small so that the stability of the four-rotor UAV in flight is improved.By comparing it with the existing ADRC control algorithm and PD control algorithm,it is concluded that this method's stability and anti-interference effect are more prominent.