基于垂向载荷转移率的微型客车侧倾敏感性研究

Study of Light Vehicle Rollover Tendency Based on Vertical-Load Transfer Rate

在Matlab/Simulink软件环境下建立某微型客车三自由度侧倾模型,分析车辆结构参数、道路输入参数及驾驶员输入参数对车辆侧倾倾向性的影响。利用干路面蛇形试验数据对所建立的仿真模型进行验证,通过J-turn试验和鱼钩仿真试验(fish-hook)分析车速、转向盘转角对车辆侧向加速度、车身侧倾角等侧向稳定性输出参数的影响。同时提出动态垂向载荷转移率(VTRd)作为侧倾敏感性因数,分析车辆结构及运行参数对微型客车侧倾敏感性的影响。结果表明:悬架侧倾刚度对侧倾敏感性影响最为明显;结合驾驶员对转向盘转角的输入,车辆的侧倾变化趋势对车速的变化比较敏感,当车速增加到80 km/h以上时,较小的转向盘转角变化就会使车辆发生侧倾。

Taking a mini-bus as the research object,a three degree freedom multi-body dynamics model is developed using Matlab/Simulink to analyze mini-bus dynamics and sharp turn stability.Using the J-turn and NHTSA Fish-hook virtual tests,the influence of vehicle velocity and steering angle on the vehicle lateral acceleration and vehicle body rollover angle are analyzed. The influences of mini-bus structure,traffic conditions,and external conditions on the rollover tendency were alsoanalyzed in single-factor experiments. A correlation between the vehicle parameter of center of gravity location and rollover propensity is found,and the results show that the vehicle center of gravity is the most important parameter which influenced the rollover tendency of mini-bus,and combined of the vehicle velocity,the steering velocity also has some influence on the rollover stability of mini-bus. The results can be used to improve mini-bus redesigns,to improve risk prediction,and to reduce the incidence of traffic accidents.