十一自由度汽车动力学模型及舒适性仿真

Eleven DOF Vehicle Dynamics Model and Comfort Simulation

为分析和提高轿车的乘坐舒适性,将某款轿车简化为十一自由度动力学模型,由达朗贝尔原理导出系统的振动微分方程。在考虑左右轮迹相关性及前后轮迹迟滞性的基础上,利用滤波白噪声法及传递函数法,建立路面随机激励的时域模型。随后在Simulink中建立人—车—路系统仿真模型,对轿车在不同车速下不同位置的人体振动响应进行了仿真分析,通过求解加权加速度均方根值评价出各乘员的乘坐舒适性。最后进行实车试验,验证了模型的正确性。结果表明,在原车速下,所有乘员没有不舒适感。随着车速的增加,前排乘客和驾驶员的主观感受越来越强,而后排乘客的主观感受由没有不舒适增加到稍有不舒适。

In order to analyze and improve the ride comfort of the car, a certain car is simplified as a dynamic model with eleven degrees of freedom. The vibration differential equations of the model are deduced by using D＇Alembert principle. A time domain model of random road excitation is established by the method of filtered white noise and the transfer function~ It considers the spatial correlation of vehicle＇s left and right wheels track excitation and the hysteresis of vehicle＇s fiont and rear wheels track excitatior~ The human-vehicle-road system simulation model is established in Simulink, and the simulation and analysis of human vibration response in vehicle at different speeds are carried out. Then passengers＇ ride comforts are evaluated by solving the weighted acceleration root mean square value. Finally, the real vehicle test is carried out to verify the correctness of the model. The result shows that all the crew do not feel uncomfortable at original speed. As the speed creases, the subjective feelings of the front passenger and the driver are getting stronger and stronger, the rear passengers＇ feelings change from no discomfort to slight discomfort.