连续工况下基于PID+LQR算法的自动驾驶车辆横纵向耦合控制

为提高自动驾驶车辆的路径跟踪精度,针对自动驾驶车辆横纵向耦合控制问题,提出了带有前馈控制的PID+LQR联合控制策略。首先,利用二自由度车辆动力学构建路径跟踪误差数学模型,制定横纵向控制流程。随后,设计了用于横向控制的LQR控制器和用于纵向控制的PID控制器,将横纵向控制器进行整合,使得车辆在接收到决策规划系统给出的期望指令后可以进行跟踪行驶。借助CarSim和MATLAB/Simulink联合仿真平台,在连续工况下对该控制策略进行测试。结果表明,提出的横纵向耦合运动控制策略可以控制车辆沿着规划的轨迹行驶,且可将跟踪误差控制在较小的范围内。

Lateral and Longitudinal Coupling Control of Autonomous Vehicle Based on PID+LQR Algorithm Under Continuous Conditions

In order to improve the path tracking accuracy of autonomous vehicles, a PID+LQR joint control scheme with feedforward control was proposed for the lateral and longitudinal coupling control of autonomous vehicles. Firstly, a mathematical model of the path tracking error is established based on the two-DOF vehicle dynamics model, the lateral and longitudinal control strategy is proposed. Then, the LQR controller for lateral control and PID controller for longitudinal control are designed. The lateral and longitudinal controllers are integrated so that the vehicle can track driving after receiving the expected instructions given by the decision planning system. The control strategy under continuous conditions is tested with the help of the CarSim and MATLAB/Simulink co-simulation platform. The results show that the proposed lateral and longitudinal coupling motion control strategy can control the vehicle along the planned trajectory. And the tracking error can be controlled within a small range.