摘 要

汽车悬架功能系统是汽车结构的重要组成部分之一，随着汽车科技的发展与升级，人们对汽车性能舒适性的要求不断提高，特别是操纵稳定性和行驶平顺性，这取决于汽车悬架功能系统的好坏。目前，汽车上普遍采用的是被动悬架，它是由弹簧等弹性元件与减震元件组成的。被动悬架难以同时改善车辆在不平路面上高速行驶时的操纵稳定性和行驶平顺性，难以适应由路面不平引起的复杂变化。本文所研究的主动悬架是最近几年来提高汽车悬架性能的主要途径之一，主动悬架能够根据路面的激励情况及汽车运动的实际情况，控制车身和轮胎的位移还有车身垂直加速度，使汽车整体行驶性能达到最佳。而且主动悬架可以调节悬架的参数，能够实时调整和产生主动作用力，并且使得悬架处于最优反馈控制，克服了被动悬架在汽车性能上的限制和不足。

本文通过研究并运用了汽车动力学理论，建立了四分之一车身的被动悬架与主动悬架动力学模型，主动悬架则采用PID控制和模糊控制策略来进行研究，并以积分白噪声形式中的B级路面激励做为输入，通过Matlab中Simulink进行仿真。通过分析结果分别给出不同控制策略的不同的控制能力，实验结果表明，拥有主动悬架的汽车的操纵稳定性和行驶平顺性比拥有被动悬架的汽车的要有效，其中车身加速度是影响稳定性和平顺性最主要的原因。

关键词：主动悬架系统和被动悬架系统力学模型；PID控制；模糊控制；路面激励模型

Design of Vehicle Active Suspension Control System

ABSTRAT

The automobile suspension function system is one of the important components of the automobile structure. With the rapid development of the automobile industry, people's requirements for the performance of modern automobiles are constantly increasing, especially the handling stability and ride comfort, depending on the function of the automobile suspension. The system is good or bad. At present, passive suspension is widely used in automobiles. It is composed of elastic elements such as springs and damping elements. Passive suspension is difficult to improve the stability and smoothness of the vehicle when driving at high speeds on uneven roads, and it is difficult to adapt to the complexity caused by uneven roads. In recent years, active suspension has become a new way to improve the performance of automobile suspension. The active suspension can control the displacement of the vehicle body and the tire as well as the acceleration according to the excitation condition of the road surface and the actual condition of the automobile, so that the overall running performance of the automobile can be optimized. Moreover, the active suspension can adjust the parameters of the suspension, can adjust and generate the active force in real time, and make the suspension in the optimal feedback control, which overcomes the limitations and deficiencies of the passive suspension in the vehicle performance.

In this paper, the dynamics model of passive suspension and active suspension of a quarter body is established by studying and applying the theory of vehicle dynamics. And take the class B road surface excitation in the form of integral white noise as the input, and carry on the simulation through Simulink in Matlab. The experimental results show that the driving stability and ride comfort of vehicles with active suspension are more effective than that of cars with passive suspension, and different control abilities of different control strategies are given respectively.

Keywords: Active suspension system and passive suspension system mechanical model; PID control; fuzzy control; pavement excitation

目 录

第1章 绪论 1

1.1车辆悬架系统介绍 1

1.2悬架分类及各自性能 2

1.2.1被动悬架 2

1.2.2主动悬架 3

1.3国内外主动悬架的发展背景与趋势 3

1.3.1主动悬架的发展现状 3

1.3.2主动悬架的控制理论 4

1.4主动悬架控制理论的研究目的及意义 5

1.5论文的主要研究内容 5

2.1路面激励模型 6

2.1.1路面不平度功率谱 6

2.1.2路面的空间与时域模型 7

2.2悬架模型建立 9

2.2.1概述 9

2.2.2被动悬架的四分之一车身二自由度模型 10

2.2.3主动悬架的四分之一车身二自由度模型 12

第3章 主动悬架控制理论 14

3.1主动悬架的PID控制 14

3.1.1PID控制 14

3.1.2主动悬架的PID控制 15

3.2主动悬架的模糊控制 16

3.2.1模糊控制理论 16

3.2.2主动悬架模糊控制设计 17

第4章 仿真结果与分析 22

4.1主动悬架PID控制仿真 22

4.2主动悬架模糊控制仿真 23

第5章 总结 25

致 谢 26

参考文献 27

1. 绪论

1.1车辆悬架系统介绍

汽车悬架是车身与车轮之间所有力传递连接的总称。通过汽车悬架系统，能够将由路面激励作用于轮胎上的支撑力、驱动力或者约束力以及横向反作用力传递到车体上，使汽车能够保持稳定，并且无论在何种路面上都能够稳定行驶。

如图1.1所示的汽车悬架一般是由弹性组件、减振器、横向推力杆及纵向推力杆和横向稳定器组成，弹性组件起到缓冲作用、减振器起到减振作用、横纵向推力杆起到力的传递的作用，还有横向稳定器起到稳定车身的作用。