汽车车身时滞减振控制理论与试验研究

Generally, the automotive body vibration is caused by the exciting forces from the engine and the road irregularity, excitations of the engine and the road irregularity are transferred to the body through the mounting system and the suspensions respectively. In the past, most of the researches about active suspensions and mountings with delay mainly focused on the negative effects brought in by the time delay. In this project, a delay control theory is presented to suppress the vibration the body. .The project mainly includes: (1) research on solving method of time delay dynamics equations, it will provide a novel method to solve the differential equations with delay; (2) research on the dynamics modeling for the vibration-suppressed of automotive body with time delay control, it is to determine the feedback types and the feedback objects; (3) research on optimization of the control parameters, it provides a more universal method to determine the feedback gains and the corresponding time delays; (4) research on time delay control theories of the automotive body under different working conditions such as idle, harmonic excitation, pulse excitation and random road irregularity. (5) research on experiments about suppressing vibration of the automotive body,it includes the constructing of the test bench, determination of the physical characteristics of the actuator, the design and development of the controller and the tests under different working conditions..Through the study of the project,Achieving the goals: (1) a basic theory and analysis frame system is constructed for suppressing vibration of automotive with time delay; (2) the delay control experimental foundation for the vibration-suppressed of the body is established; (3) a design basis for the suspension/mouting of the delay vibration-suppressed control is provided

车身的振动源主要来自发动机和路谱，发动机引起的激励通过悬置传递给车身，路谱的激励通过悬架传递给车身。本项目通过在被动悬置和悬架中增加时滞反馈控制来达到车身减振的目的，过去在研究带有时滞的主动悬架/悬置时，大多数学者都是研究时滞的不利影响，而本项目是想如何利用时滞减小车身的振动。主要研究内容：（1）时滞动力学的求解方法研究，为时滞动力学方程求解提供一种崭新的方法；(2）车身时滞减振控制的动力学建模研究，主要是确定反馈控制对象和反馈控制类型；（3）反馈控制参数的优化研究,提供一种确定反馈增益系数和时滞的一种较为通用方法；（4）不同工况下车身时滞减振控制理论研究：怠速工况时滞减振控制、谐振激励时滞减振控制、脉冲激励时滞减振控制和随机路谱激励时滞减振控制；（5）车身时滞减振控制的试验研究：试验台架的研制、作动器的物理特性确定、控制器的设计与开发和不同工况下车身时滞减振的试验研究。

车身的振动源主要来自发动机和路谱，发动机引起的激励通过悬置传递给车身，路谱的激励通过悬架传递给车身。本项目通过在被动悬置和悬架中增加时滞反馈控制来达到车身减振的目的，改变了过去在研究带有时滞的主动悬架/悬置时，多数学者都是研究时滞的不利影响，本项目主要研究如何利用时滞减小车身的振动。项目实施过程中研究了时滞反馈控制的动力学建模及相关应用。讨论了随机路谱激励下车身时滞减振控制及时滞反馈最优控制参数的优化问题。提出了一种利用速度和位移反馈控制减缓车辆悬架的三次强非线性振动的优化控制方法。针对四自由度半车悬架控制模型，提出一种基于双时滞反馈优化控制的车辆半主动悬架控制方法。建立了含时滞状态反馈控制的1/4车辆悬架模型，采用稳定性切换方法对车辆悬架系统的稳定性进行分析。针对具有时滞减振主动控制技术的非线性悬架，研究时滞和非线性因素对车辆悬架系统减振性能的影响。建立了设计、搭建了1/4车模型的试验装置，建立了完整的车身时滞减振控制的试验基础，并进行了部分不同激励下的汽车车身时滞减振试验。理论分析与试验结果，为时滞减振悬置和悬架的设计提供依据。