原地转向工况电动轮铰接车特性建模分析

Modeling and Analysis of the Characteristics of In-Situ Steering of Articulated Motor-Driven Dump Truck

电动轮铰接车原地转向工况对整车转向系统要求较高,是整车设计必须考核的工况,但较少涉及三维实体车辆原地转向仿真分析。根据电动轮铰接车结构特点,基于ADAMS搭建其动态运动模型;基于AMESim搭建全液压转向系统模型,联立整车模型和转向系统模型搭建联合仿真模型;通过驱动转向油缸使铰接车达到最大铰接角,实现铰接车原地转向过程仿真分析。仿真得到铰接车前后车体质心及铰点的运动轨迹,各个轮胎所受侧向力、纵向力及垂直力随铰接角的变化曲线,转向油缸中活塞杆的受力和铰接体的受力。结果可知:前车体内外车轮所受纵向力的方向相反;外侧车轮仅前轮纵向力较大,后两轮的纵向力可忽略不计;对于侧向力而言,六轮受力都较为明显,且中间两轮与其它四轮在方向上是相反的,且在数值上明显大于另外四轮,这也是六轮铰接车不同于四轮车的一个显著特点;原地转向时内侧活塞杆的受力大于外侧。

Articulated motor-driven dump truck in situ steering conditions which is the necessary conditions for the vehicle design take higher requirements to vehicle steering system,but less involved in three-dimensional vehicle in situ steering simulation analysis.According to the structural characteristics of the electric wheel articulated car,the dynamic motion model is built based on ADAMS;Based on AMESim,the joint simulation model is established by using the integrated hydraulic steering system model,the simultaneous vehicle model and the steering system model.The maximum hinge angle of the articulated vehicle is driven by the steering cylinder to realize the simulation analysis of the turning process of the articulated vehicle.The simulation shown that the centroid of the car body before and after,the movement trajectory of hinge,The variation of the lateral force,longitudinal force and vertical force of each tire with the hinge angle.The results show that the front and rear wheels are in the opposite direction to the longitudinal force of the wheel;the outer wheel only has a large longitudinal force.The longitudinal forces of the rear wheels are negligible.For the lateral force,the force of six-wheels are more obvious,and the two wheels in the middle with the opposite direction for other four rounds,and the value is significantly greater than the other four rounds,which is also a distinctive feature of the six-wheel articulated car unlike the four-wheel car in situ steering when the inner piston rod force is greater than the outside.