基于改进动态逆的四旋翼无人机三维路径跟踪控制

3D Path Tracking of Quadrotor Based on Improved Dynamic Inversion

为了克服无人飞行器控制系统中欠驱动与变量间强耦合的问题,常采用需要被控对象精确数学模型的动态逆方法,但飞行器负载发生变化时因模型误差的引入,精确路径跟踪难以保证。提出了一种改进动态逆方法,即在四旋翼系统快变量环路(姿态控制环)中引入模型参考自适应与动态逆相结合的方法,从姿态与位置两方面设计了完整的路径跟踪控制器。最后,基于pixhawk飞控板搭建的四旋翼硬件实验平台参数对所提出的控制方案进行MATLAB仿真分析,与传统动态逆方法相比,改进动态逆方法在负载减少10%情况下能较快适应模型参数的变化,具有更稳定和精确路径跟踪性能。

Dynamic inversion method that requiresa precise mathematical model of the controlled object is often used to overcome underactuation and strong coupling in variables in the control of UAV( Unmanned Aerial Vehicle),but perfect tracking cannot be guaranteed with the introduction of model error caused by load change of the vehicles. This paper proposed an improvement for combining MRAC( Model Reference Adaptive Control) with dynamic inversion in the fast variable loop( attitude control loop). A complete path tracking controller is designed from two aspects( attitude and position). Finally,the MATLAB simulation for the proposed scheme is analyzed based on the parameter of a pixhawk quadrotor hardware experimental platform. With respect to conventional dynamic inversion method,10% weight is reduced from it's load during the flight. The improved control structure can quickly adapt to model parameter change and have higher precision tracking performance than conventional ones.