四旋翼飞行器的自抗扰飞行控制方法

针对四旋翼飞行器参数不确定性和外部干扰敏感的问题,本文提出一种基于自抗扰控制器的控制系统设计方法.在为期望姿态和高度安排过渡过程的基础上,设计了扩张状态观测器对内扰和外扰进行估计并实时补偿,能够很好地克服飞行器的强耦合性、模型不确定性以及风速变化等外部干扰问题.此外本文还设计了非线性状态误差反馈控制律来有效抑制跟踪误差.在仿真平台上对自抗扰控制系统进行稳定控制、姿态跟踪、高度控制、抗扰性及鲁棒性实验,并与串级PID控制系统进行定量对比分析.仿真结果表明,本文所设计的自抗扰控制器不仅能够很好地估计并补偿系统所受内外部干扰,而且对四旋翼飞行器参数的不确定性具有较强的鲁棒性,能够满足飞行器姿态调节快速和高稳定度的控制要求,性能指标明显优于串级PID控制器.

An active disturbance-rejection flight control method for quad-rotor unmanned aerial vehicles

We design an active disturbance-rejection controller for the flight control of a quad-rotor unmanned aerial vehicle (UAV) to reduce the effects of the parameter variations and external disturbances. After arranging the transient dynamics of the desired attitude and height, we design an extended state observer to estimate and compensate for the impact of internal/external disturbances simultaneously, thus solving the problems of strong coupling and parametric uncertainties even in the presence of external disturbances such as varying-wind conditions. Moreover, a nonlinear state error feedback control law is also applied, which effectively reduces the tracking error. A series of experiments are conducted in simulation platform, and comparative analysis between active disturbance-rejection controller and cascade PID controller is made. Simulation results show that the active disturbance-rejection controller not only accurately estimates and compensates the internal/external disturbances but also implements the robust quad-rotor flight control under conditions of dynamic parametric uncertainties, meeting the design requirements of fast attitude maneuver and high stability, and showing a superior performance to cascade PID controller.