二系横向刚度和阻尼对一次蛇行的影响分析

Influence of lateral stiffness and damping of the second suspension on primary hunting process

为探究二系悬挂参数对车辆一次蛇行的影响,在MATLAB中建立了车辆系统的线性模型。基于模糊数学中的欧式贴近度,追踪了车辆系统的模态,并给定了耦合度概念。利用敏感性系数,表征了车辆系统耦合度受各因素影响的灵敏程度。以降低系统耦合度为目标,研究了二系横向刚度和阻尼对一次蛇行的影响。结果表明:在一定范围内,增大二系横向阻尼或减小二系横向刚度可有效降低系统的耦合度,减小车体的横向耦合振动。

In order to research the influence of the second suspension parameters on primary hunting of vehicle,a linearization model of vehicle is established by MATLAB in this thesis.Based on the Euclidean Closeness which belongs to fuzzy mathematical,the modals of vehicle are tracked accurately and the concept of modal coupling degree is defined.Besides,sensitivity coefficient is defined to characterize the sensitivity of vehicle system’s modal coupling degree to various factors.In order to decline the coupling degree of vehicle system,the effect of stiffness and damping of second suspension parameters are studied.The results show that increasing the lateral damping or reducing the stiffness of the second suspension can effectively reduce the coupling degree of the system and decline the lateral coupling vibration of the car body.