基于自适应模糊PID控制的农用作业机械轨迹跟踪系统研究

A Novel Adaptive Fuzzy PID Controller for Trajectory Tracking System of Agricultural Machinery

为实现具备大转向间隙特征的智能农业作业机械的轨迹跟踪的稳定性和精确性,提出了一种新型的自适应模糊PID控制器。首先,基于预瞄跟踪理论,建立二自由度(2-DOF)车辆横向误差模型,并推算出其航向角误差。然后,提出了基于转角前馈补偿的自适应模糊控制器,根据驾驶员特性,建立模糊控制规则。最后,利用Carsim与Simulink进行联合仿真验证。结果表明:相比传统PID控制器,自适应模糊PID控制器可以有效地解决大转向间隙造成的转向控制稳定性问题,减少智能农机轨迹跟踪时的调整时间,提高跟踪精度,对较差的车况和工作环境具有较强的适应性和鲁棒性。

In order to realize the stability and accuracy of the trajectory tracking of intelligent agricultural machinery with the characteristics of large steering gap, a new adaptive fuzzy PID controller is proposed in this paper. Firstly, the lateral error model of 2-DOF vehicle is established based on the predict point theory, and its course angle error is calculated. Then, an adaptive fuzzy controller based on the steering wheel angle feedforward compensation is proposed, and the fuzzy control rules are established according to the characteristics of the driver. Finally, the model was simulated by Carsim and Simulink, and the results proved that compared with the traditional PID controller, the adaptive fuzzy PID controller can efficiently solve the problem of steering stability caused by the large steering gap, reduce the adjusting time of the intelligent agricultural machinery of trajectory tracking, improve the tracking accuracy, and has stronger adaptability and robustness even under poor vehicle conditions and harsh environment.