五轴重型全轮转向汽车操纵稳定性分析

Handling Stability Simulation and Analysis of Five-axle Heavy-vehicle Based on All-wheel Steering

针对五轴重型汽车低速机动性差、高速稳定性不好的问题,建立了五轴汽车全轮转向的二自由度模型和运动微分方程,采用零质心侧偏角的控制策略,推导了各轴的转角比例系数及相关的状态空间矩阵及传递函数,对全轮转向、前两轴转向、第一轴转向3种转向模式下的操纵稳定性进行了分析比较。结果表明,五轴重型汽车采用全轮转向有利于提高低速转向时的机动性和高速转向时的稳定性。

Aimed at the big radius at low speed and bad stability at high speed of five-axle heavy-vehicle with front-wheel-steering, the multi-axle steering technology of five-axle heavy-vehicle was analyzed. A 2-DOF （2-degree of freedom） model and differential equations of five-axle vehicle with all-wheel steering were established. The steering angle ratios of different axles, state condition matrix, transfer functions were obtained based on zero side-slip angle of mass center control strategy. Finally, the handling stability performance of the five-axle vehicle with three steering models were simulated and compared. The results prove that multi-axle steering can decrease the steering radius at low speed and improve vehicle stability at high speed, and five-axle vehicle with all-wheel steering has the best handling stability.