Dynamic Resonant Frequency Bands of Suspension System of Vehicles with Varying Speeds Based on Time⁃Frequency Spectrum  

基于时频谱的变速行驶车辆悬架系统动态共振频域特性研究

作　　者：ZHANG Buyun ZENG Falin TAN Chin-An 张步云;曾发林;TAN Chin-An(江苏大学汽车工程研究院,中国镇江212013;美国韦恩州立大学机械工程学院,美国底特律48202)

机构地区：[1]Automotive Engineering Research Institute,Jiangsu University,Zhenjiang 212013,P.R.China [2]Department of Mechanical Engineering,Wayne State University,Detroit 48202,USA

出　　处：《Transactions of Nanjing University of Aeronautics and Astronautics》2021年第2期333-343,共11页南京航空航天大学学报（英文版）

基　　金：This work was supported by the National Natural Science Foundation of China(No.51705205)。

摘　　要：The dynamic responses of suspension system of a vehicle travelling at varying speeds are generally nonstationary random processes,and the non-stationary random analysis has become an important and complex problem in vehicle ride dynamics in the past few years.This paper proposes a new concept,called dynamic frequency domain(DFD),based on the fact that the human body holds different sensitivities to vibrations at different frequencies,and applies this concept to the dynamic assessment on non-stationary vehicles.The study mainly includes two parts,the first is the input numerical calculation of the front and the rear wheels,and the second is the dynamical response analysis of suspension system subjected to non-stationary random excitations.Precise time integration method is used to obtain the vertical acceleration of suspension barycenter and the pitching angular acceleration,both root mean square(RMS)values of which are illustrated in different accelerating cases.The results show that RMS values of non-stationary random excitations are functions of time and increase as the speed increases at the same time.The DFD of vertical acceleration is finally analyzed using time-frequency analysis technique,and the conclusion is obviously that the DFD has a trend to the low frequency region,which would be significant reference for active suspension design under complex driving conditions.车辆变速行驶时悬架系统的动态响应通常是非平稳随机过程,对其进行时频分析是近年来车辆平顺性研究中的重点与热点问题。本文依据人体对不同频带的振动敏感性不同,提出动态频域概念以开展非平稳车辆动力学评价研究,主要包含前后轮输入数值分析与非平稳随机激励下悬架系统时频特性研究。应用精细积分法获得悬架系统的垂向加速度与俯仰角加速度,研究不同加速度工况下的响应均方根值。结果表明,非平稳激励下响应均方根值为时间的函数,同时随速度增加而增大,且垂向加速度的动态频域区间有向低频迁移的趋势,可为复杂驾驶工况下主动悬架的设计提供重要参考依据。

关 键 词：non-stationary random process suspension system vehicle modeling dynamical frequency domain(DFD) ride comfort 

分 类 号：O324[理学—一般力学与力学基础]