摘要
为了更好地兼顾高速转向时汽车的操纵稳定性和平顺性,建立了包含主动悬架系统、Magic非线性轮胎模型和四轮转向系统的整车动力学模型。考虑了侧倾力矩和轮胎垂直载荷转移的影响,基于LQG(Linear Quadratic Gaussian)控制理论和模糊控制理论分别设计了主动悬架的最优控制器和四轮转向系统的模糊反馈控制器,并通过两者间的协调在附着系数为0.8的B级路面上对汽车进行仿真,然后分析了协调控制方法在另一附着系数路面上的有效性。结果表明,与无控制系统相比,协调控制下车身侧倾角峰值减少了36.6%,车身垂直加速度均方根值下降了14.2%,质心侧偏角接近目标零值;协调控制方法在两种常见附着系数路面上均能达到预期的效果,而且随着附着系数的增大,汽车的操纵稳定性和平顺性改善越好。说明所设计的协调控制器能够有效地改善高速转向时汽车的操纵稳定性和平顺性。
Abstract： In order to better balance handling stability and ride performance of vehicle at high speed steering condition, a vehicle dynamics model is established, which includes active suspension sys- tem, Magic nonlinear tire model and four wheel steering system. A LQG（ Linear Quadratic Gaussi- an） controller of active suspension and a fuzzy controller of four wheel steering system are designed based on the LQG control theory, the fuzzy control theory and given effect of rolling moment on body posture and the transition of tire vertical load. Through the coordination between the two controllers vehicle model was simulated in B class road when the road friction coefficient was 0.8. Then the ef- fectiveness of the coordination control method on other adhesion coefficient road was analyzed. The results illustrated that the coordination control strategy, in which peak of body roll angle decreased by 36.6% , root mean square value of body vertical acceleration was reduced by 14. 2% and sideslip angle was close to the target value of zero. The coordination control method could achieve the desired results on two common adhesion coefficient roads. And as the adhesion coefficient increased, handling stability and ride performance of vehicle were greatly improved. The coordination controller could effectively improve handling stability and ride performance of vehicle at high speed steering condition.
出处
《广西大学学报（自然科学版）》
CAS
北大核心
2016年第3期674-683,共10页
Journal of Guangxi University（Natural Science Edition）
基金
国家自然科学基金资助项目(51375212)
江苏省汽车工程重点实验室开放基金项目(QC201304)
关键词
汽车
主动悬架
非线性模型
四轮转向
模糊控制
vehicle
active suspension
nonlinear model
four wheel steering
fuzzy control
