四轮转向汽车操纵稳定性研究

Research on Handling Stability of Four-wheel Steering Vehicle

为了研究转向工况对四轮转向汽车操纵稳定性的影响,基于Matlab/Simulink建立四轮转向汽车前轮转角比例前馈加横摆角速度模糊PID反馈控制模型,通过与Trucksim车辆模型和Simulink控制模型联合仿真,分别在低速和中高速下进行方向盘角阶跃输入离线仿真和方向盘正弦角输入实时仿真试验,与前轮转向汽车在相同工况下侧向加速度、横摆角速度以及质心侧偏角的仿真结果进行对比分析。试验结果表明:四轮转向控制仿真结果优于前轮转向结果,搭建的四轮转向前轮转角比例前馈加横摆角速度模糊PID反馈控制策略,能提高汽车低速转向时的操纵轻便性和机动性以及中高速转向时的操纵稳定性。

In order to research the influences of steering working conditions on handling stability of a ve-hicle with four-wheel steering, a front-wheel-angle-ratio-feedforward plus yaw-velocity fuzzy PIDfeedback controller model for the vehicle was established with Matlab/Simulink. Combining vehicle mod-el in Trucksim and controller model in Simulink, the off-line simulation under the steering wheel anglestep input and the real-time simulation under the sine angle input of the steering wheel were carried out,and comparisons were made with the simulation under the same inputs of the front-wheel-steering vehi-cle. The results show that the performance of four-wheel-steering control is better than front-wheel-steering alone, the established four-wheel-steering front-wheel-angle-ratio-feedforward plus yaw-ve-locity fuzzy PID feedback control strategy can effectively improve both maneuverability of the vehicle atlow speeds and handling stability of the vehicle at high speeds.