非平稳随机激励下悬架系统动态频域分布研究

摘要

车辆在变速行驶状态下所受路面激励是非平稳随机过程;针对此状态下悬架系统动力学响应在时域和频域分布问题,基于车速参数通过线性时变系统法建立车辆所受路面激励模型.提出“动态频域”概念,建立1/4悬架系统模型.利用精细积分法研究车速变化导致的车身振动响应峰值频带变化特性,揭示非平稳随机激励下系统响应动态频域分布规律.研究可为非平稳随机振动变频域控制与应用提供理论参考,并为提高车辆在复杂行驶工况下的运行品质提供一种新的思路.%The road excitation to vehicles,which are on variable driving conditions such as acceleration or deceleration,is a complex non-stationary random process.In order to improve the ride and operation performance of vehicles on this state,a new time-frequency model of the road excitation to the whole vehicle is established by linear time variable system method based on the velocity,and the relationship between the velocity and coherence time-frequency domain distribution of multiple non-stationary random inputs is studied.The one quarter suspension system model is established,and the peak frequency span variation characteristics of vehicle body due to the variable velocity is researched by PIM(Precise Integration Method).The research can provide academic reference for variable frequency domain control and application of non-stationary random vibration,and provide a new thought for improving the vehicle operation quality on the complex riding conditions.