结构参数变化对转向机构性能影响分析

Effect Analysis of Changing Structure Parameter on Steering Mechanism Performances

车辆转向系统中存在诸如弹性变形、运动副间隙等诸多的不确定影响因素,这些参数使得建模设计与实际车辆的运动存在一定的偏差,使得轮胎的磨损加重,对车辆的安全稳定运行具有重要影响。基于参数横拉杆弹性变形、运动副间隙等的不确定性,基于转向系统的运动模型和动力学模型,建立系统刚柔耦合的分析模型,分析横拉杆和运动副间隙分别单独作用及工作作用时不同运动状态下对机构性能的影响;结果可知:在转向过程中,柔性体横拉杆对转向轮转角影响有限,但是对运行过程中的轮距和外倾角变化影响较大,且对车轮跳动过程中车轮摆动影响显著;运动副A、B内间隙大小与碰撞力存在很大程度的非线性;运动副A、B内的摩擦能够降低碰撞接触的强度;横拉杆在车轮跳动状态时受力最大。

There are obvious uncertainties in the elastic deformations of the tie rod and joint clearances in the steering mechanism.Such uncertain parameters will cause the deviation of the whole vehicle movement and aggravate the wear of the tire,which will have an important impact on the handling stability of the vehicle.Based on steering kinematics analysis,ADAMS and ANSYS were used to build rigid flexible coupling vehicle model containing flexible bodies which realize the combination of finite element analysis and multi rigid body model.The model of the steering mechanism with single clearance and multi-gap motion pair was established,and the collision contact characteristics of the pair were analyzed and analyzed,and the motion characteristics and the collision of the steering mechanism with the flexible pair and the tie rod were also analyzed.The results show that the flexure tie rod has a limited influence on the turning angle of the steering wheel during the steering process,but has great influence on the track and camber during the process of running,and the effect of the wheel sway is remarkable.The friction between the pair A and B can reduce the strength of the collision contact;the force of the tie rod in the beating state of the wheel is the biggest;and it provides a reference for this kind of design research.