基于干扰观测器的四旋翼无人机轨迹跟踪控制

Trajectory Tracking Control of Quadcopter UAV Based on Disturbance Observer

针对四旋翼无人机轨迹跟踪控制过程中易受多源外界干扰影响的问题,为了进一步提升其控制精度和抗干扰性能,该文使用了一种基于指数收敛干扰观测器的双幂次趋近率滑模控制策略。首先,基于牛顿-欧拉方法建立了四旋翼无人机数学模型,并将四旋翼无人机控制系统分为外环位置环和内环姿态环的双回路控制结构;其次,分别在位置子系统和姿态子系统采用了滑模控制方案,并重点针对姿态环设计了基于双幂次趋近率的滑模控制器;最后,设计了一种指数收敛干扰观测器,对四旋翼无人机所受多源外界干扰进行实时观测和补偿。与传统内外环控制结构的PD控制方案相比,仿真实验验证了所提控制策略具有更优的动态响应性能和更高的控制精度,且抗干扰能力得到极大增强。

To tackle the issue of susceptibility to multiple external disturbances in the trajectory tracking control process of quadrotor unmanned aerial vehicles(UAVs),in order to further enhance its control accuracy and disturbance rejection capability,this paper adopts a dual power-rate sliding mode control strategy based on an exponential convergence disturbance observer.Firstly,a mathematical model of the quadrotor UAV was established based on the Newton-Euler method,and the quadrotor UAV control system was divided into a dual-loop control structure of the outer ring position loop and the inner ring attitude loop.Secondly,the sliding mode control scheme was adopted for the position subsystem and attitude subsystem,respectively,and the sliding mode controller based on double-power approach rate was designed for the attitude ring.Finally,an exponentially convergent interference observer was designed to observe and compensate for the multi-source external interference of quadrotor UAV in real time.Compared with the PD control scheme based on the inner and outer loop control structure,simulation experiments verify that the proposed control strategy has better dynamic response performance and higher control accuracy,and the anti-interference ability is greatly enhanced.