汽车ABS系统仿真研究

摘要

摘 要

本文首先剖析了防抱死制动系统的控制原理，在此基础上详细介绍了ABS的结构以及各部分的作用，并建立了仿真模型。仿真模型充分考虑了车体的力学模型、轮胎力学模型、制动系统模型。为达到仿真可行性与可信度的统一本文对模型均做了合理简化。

本文在总结前人工作的基础上，主要侧重于汽车 ABS 控制算法的理论研究。文章首先介绍了目前常用的ABS 控制方法，包括逻辑门限值控制方法和于滑移率的控制方法，并分析了各自的优缺点。由于 ABS是一个时变非线性系统，而滑模变结构控制对系统不确定性及外部干扰具有良好的自适应性，因此本文在建立 ABS 动力学系统模型 (包括车辆动力学模型、轮胎模型、液压系统模型和制动器模型)的基础上将滑模变结构控制引入ABS控制系统中，并针对滑模控制的缺点设计了一个带有扰动观测器的无抖振滑模控制器应用于ABS，通过使用扰动观测器对系统模型的不确定因素进行补偿，并设计了光滑的控制规律来消除滑模控制固有的抖振现象。此外，针对防抱死制动系统研究中存在的最佳滑移率寻优及参考车速估算等关键问题，本文采用的自寻优控制算法可以实现在不需要路面辨识的情况下对车轮滑移率在线寻优，另外利用减速度信号，结合已有的车轮轮速对参考车速进行在线计算，使问题得到有效解决。 关键词:防抱死制动系统，滑模控制，扰动观测器，抖振，自寻优控制

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Abstract

This paper analyzes the control principle of anti-lock braking system, on the basis of a detailed description of the tructure and the role of each part, and the simulation model. The simulation model takes into account the dynamic model of the vehicle, the tire mechanics model, the braking system model. In order to achieve the simulation feasibility and credibility of unity, the paper have done a reasonable simplified model.

This paper summarizes the basis of previous work, mainly focused on automotive ABS control theory algorithmsThe study. The article first introduces the most commonly used ABS control method comprising logic threshold control partyLaw and based on the slip rate control method, and analyzed their advantages and disadvantages. Since the ABS is a time.Variable nonlinear system, variable structure control of the system uncertainties and external disturbances have good.Adaptability, this article in establishing ABS system dynamics model (including vehicle dynamics model,Tire model, the hydraulic brake system model and model) will be the basis to introduce variable structure control.ABS control system, and for the shortcomings in the design of the sliding mode control with a disturbance observer without shaking.Vibration sliding mode controller applied to ABS, by using the disturbance observer of uncertainty into the system model.Compensate, and smooth control law is designed to eliminate sliding mode control inherent chattering. In addition,Optimize and reference speed for optimum slip ratio estimation lock braking system existed in the research and other key.Questions for optimizing control algorithm used in this paper can be achieved without the need for identification of the road.Wheel slip ratio line optimization, in addition to the use of the deceleration signal, combined with the existing wheel speed of the reference.Online calculation speed, so that the problem be effectively addressed.

Keywords: anti-lock braking system, sliding mode control, the disturbance observer, chattering, self optimizing control.

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目录

目 录

摘 要.............................................................. I Abstract .......................................................... II 目录.............................................................. III 第1章 绪论 ............................................................................................................................... 1

1.1 本课题的研究背景 ..................................................................................................... 1 1.2 ABS发展历程概述 ............................................. 3

1.2.1 ABS系统的概念 ......................................... 3 1.2.2汽车ABS的研究现状 ..................................... 3

1.2.3 ABS在国内外的发展情况 ................................. 4 1.3汽车ABS的重要性及制动状况分析 ............................... 5 1.4本文主要研究任务 ............................................. 8 第2章 汽车ABS系统的工作原理及过程 ........................................................................ 9

2.1汽车ABS系统的结构及各部件的作用 .................................................................. 9

2.1.1车轮转速传感器 ........................................ 10 2.1.2电子控制单元ECU ...................................... 11 2.1.3制动压力调节器 ........................................ 12 2.2 ABS主要控制方法 ................................................................................................... 12 2.3汽车ABS系统的工作原理 ...................................................................................... 12

2.3.1汽车ABS理论依据 ...................................... 12 2.3.2汽车ABS的工作原理与工作过程 .......................... 14 2.4本章小结 ..................................................................................................................... 15 第三章 汽车ABS系统的建模 .............................................................................................. 16

3.1车辆动力学模拟的概况 .......................................................................................... 16

3.1.1人工建模及编程计算方法 ................................ 16 3.1.2 图形建模计算方法 ..................................... 16 3.1.3 计算机模拟 ........................................... 17 3.2 汽车动力学模型研究概况 ................................................................................... 17

3.2.1一般车辆模型 .......................................... 17 3.2.2 四轮汽车模型 ......................................... 17 3.3.3双轮车辆模型 .......................................... 18 3.3.4单轮车辆模型 .......................................... 18 3.3 车辆动力学模型 .................................................................................................... 19

3.3.1 轮胎模型 ............................................. 21 3.3.2 制动系统模型 ......................................... 27 3.4汽车防抱制动系统的MATLAB/SIMULINK模型 ................................................. 30

3.4.1单轮车辆子系统 ........................................ 31 3.4.2制动模型子系统 ........................................ 31 3.4.3制动模型子系统 ........................................ 32 3.5本章小结 ..................................................................................................................... 33 第四章 ABS控制算法研究和仿真试验 ............................................................................. 34

4.1 ABS控制算法概述 ............................................ 34 4.2 ABS系统逻辑门限值控制算法研究 .............................. 34

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4.2.1逻辑门限值控制的墓本方法 .............................. 35 4.2.2控制量的选择 .......................................... 35 4.2.3 典型的逻辑门限值控制过程 ............................. 35 4.3逻辑门限值控制方法几个关键问题的研究 ...................................................... 37

4.3.1制动稳定区域和不稳定区域的判定 ........................ 38 4.3.2参考车速的估计方法 .................................... 39 4.4 ABS系统仿真试验 .................................................................................................... 41

4.4.1 无ABS控制时的仿真实验 ............................... 43 4.4.2逻辑门限值方法仿真实验 ................................ 44 4.4.3仿真实验分析 .......................................... 46 4.5小结 ............................................................................................................................... 47 第5章 总结与展望 .............................................................................................................. 48

5.1工作总结 .................................................... 48 5.2 未来展望 ................................................... 48 参考文献 .......................................................... 50 致 谢............................................................. 52

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