基于模糊PID线控转向系统前轮转角控制

转向系统是乘用车的重要性能指标之一,它关系到整车的操纵稳定性以及舒适性.通过对乘用车线控转向系统结构、原理进行分析,建立了基于Simulink与CarSim的汽车线控转向系统联合仿真模型,将模糊理论应用到前轮转角控制策略中,并在整车动力学模型的基础上,设计模糊PID控制器,用于前轮转角控制.仿真结果表明:汽车低速行驶时,较小方向盘转角能实现较大的前轮转角变化,其传动比较小,驾驶员转向轻便;而高速行驶时,需要较大的方向盘转角实现前轮转角变化,传动比较大,可有效防止汽车高速抖动,提高汽车操纵的稳定性.

The control of front wheel steering angle of steer-by-wire system based on fuzzy PID

Steering system is the important performance index of the passenger car, it is related to the vehicle han- dling stability and comfort. In this paper, the structure and the principle of work are analyzed, and a Simulink joint CarSim simulation model of steer-by-wire system is established by using fuzzy theory so as to control the front wheel steering angle. A fuzzy PID controller based on the vehicle dynamics model is designed for controlling the front wheel steering angle.The simulation results show that, on one hand, the smaller steering wheel angle can achieve a larger front wheel angle and a small transmission ratio at low speed, as a result, the driver performs turns lighter; and on the other hand, the larger steering wheel angle can achieve a small change of front wheel angle and a large transmission ratio at hight speed. The controller can prevent tremors effectively at high speed and improve the stability of the vehicle manipulation.