智能车辆路径跟踪控制方法

Research on the path tracking control method for intelligent vehicles

为了提高智能车辆路径跟踪控制器的可靠性和控制精度,提出一种基于误差动力学模型的路径跟踪控制方法.基于车辆运动学模型和动力学模型建立系统误差动力学模型,并在此基础上推导出车辆路径跟踪控制的稳态控制律,利用李雅普诺夫稳定性理论验证稳态控制律的正确性.为了减小外部干扰对控制性能的影响,提高控制器的可靠性,进一步设计基于车辆侧向位移误差的瞬态控制律,并利用李雅普诺夫稳定性理论验证闭环系统的稳定性.稳态控制律和瞬态控制律构成了非线性的路径跟踪控制器.通过与车辆路径跟踪常用的线性控制器和非线性控制器对比验证所提出控制方法的有效性,线性控制器选用LQR控制器,非线性控制器选用Stanley控制器.仿真结果表明,与LQR控制器相比,所提出控制方法的路径跟踪控制精度、抗干扰性和可靠性更好.与Stanley控制器相比,所提出控制方法具有更好的路径跟踪控制精度和控制收敛速度,且在大曲率路径跟踪过程中具有更好的可靠性.

To enhance the reliability and control accuracy of the path tracking controller of intelligent vehicles,a path tracking control method based on the vehicle error dynamics model is proposed.The system error dynamics model is established based on the vehicle kinematics model and dynamics model.On this basis,a steady-state control law for path tracking control is deduced,and its correctness is proved by the Lyapunov stability theorem.In addition,to improve the anti-interference performance and reliability of the controller,a transient control law based on the lateral displacement error is designed.Then a nonlinear path tracking controller can be constituted by the steady state control law and the transient control law.The effectiveness of the proposed control method is verified by comparing it with linear and nonlinear controllers commonly used for path tracking,and the Stanley controller is chosen as a representative of nonlinear controllers,and the LQR controller is chosen as a representative of linear controllers.The results show that compared with the LQR controller,the proposed control method has better path tracking control accuracy,anti-interference,and reliability.Compared with the Stanley controller,the path tracking control accuracy and control convergence rate of the proposed control method are better,and the reliability is higher in the process of the large curvature path tracking.