汽车四轮转向模式及智能控制技术研究.pdf

1217383
分类号U463
单位代码10618
密级
号04360208
千菱文通人
硕士学位论文
论文题目:汽车四轮转向模式及智能控制术研究
Research on Modes and Intelligence Control of
Four-wheel Steering Vehide
研究生姓名:张云娟
导师姓名、职称:
杨志刚教授
申请学位门类:
工学
专名称:
车辆工程
论文答辩日期:
2007年3月29日
学位授予单位
重庆交通大学
答辩委员会主席:李伟
评阅人
李伟
黎明
2007年3月
摘要
随着现代道路交通系统和汽车技术的发展,汽车行驶的平均速度不断提高,高
速行驶的安全问题日益突出。由于在高速行驶下发生的交通事故由车辆转向稳定
性问题引起的事故量所占的比例有较大的增长势头。汽车在高速行驶下进行变换
车道、超车、弯道行驶时,车身侧偏和横摆的转向稳定性成为现代汽车亟待解决
的问题。目前,国外在提高汽车转向稳定性、机动性和转向灵活性方面所采取的
技术措施主要是采用四轮转向系统( Four Wheel Steering简称4WS)。
本论文结合重庆市教委科研项目《汽车四轮转向模式及智能控制技术研究》
对四轮转向系统进行了研究,掌握了汽车4WS系统在典型运行条件下的转向模式
和控制规律,为设计汽车4WS控制系统提供核心技术和方法。4WS控制技术的
研究在增强汽车安全性能方面有着不可忽视的作用,将对我国开发和设计具有自
主知识产权的4WS系统提供核心技术,对研发具有4WS系统的汽车有着不可估
量的社会和经济效益,具有良好的市场和发展前景。
本论文首先研究了四轮转向过程中轮胎的瞬态特性,并将其作为主要因素融
入4WS系统的数学模型中,由于大多数研究者所采用的力学模型是基于两轮车系
统的二自由度线性转向模型,与实际四轮车的转向情况有一定的差别,本论文提
出建立考虑轮胎非线性侧偏特性在内的四自由度四轮转向汽车动力学模型并对其
进行了研究;然后深入分析了四轮转向汽车在各种车速、载荷、道路的条件下后
轮随前轮的转向模式及其控制规律,在研究了影响汽车运动状态响应的各种动力
学参数的基础上,建立了描述汽车实际运动情况的数学模型,并将先进的控制理
论和方法运用到4WS控制器中。采取更有效的控制策略,研究出4WS的智能最
优控制技术;最后在理论基础的研究上运用计算机模拟技术对四轮转向系统的控
制过程进行模拟,研究其控制效果并验证了理论研究结果的正确性和可行性。
关键词:四轮转向,四自由度,建模,智能控制,仿真
Abstract
Along with the development of the modem road tr
ransportation syst
nd thu
vehicle technology, and the continuously increasing of the average speed that car drive,
the safe problem that driving car at high speed is increasingly outstanding. Because the
occupied of comparison of the traffic accident that is caused by the problem in the
stability when the vehicle changes direction in driving car at high speed has the big er
increasing trend. When the vehicle proceed to transfer the driveway, overtake another
vehicle and drive along the curve way, how to increasing stability of reducing The
carriage side of the vehicle is partial to with horizontal put for vehicle to driving car at
high speed have become the problem that modem vehicle needs to be resolved
Currently, the Four Wheel Steering(4 WS)has been used for improving the stabillity and
flexibility when the vehicle changes direction
This paper researches the Four Wheel Steering on"The Vehicle Four Wheeler
Steering Mode and Intelligence Control Technique Researches", controls the changing
direction mode and the control me ulation of the Four Wheel Steering system under the
typical working situation, put forward to the manipulative technique that have the actual
applied worth on 4WS, provide the core technique and method for designing 4WS
system. The research of the manipulative technique on 4WS have very important
function, which will provide core technique for developing and designing the 4ws
system that have independence intelligent property right in the domestic, and have the
social and economic perfomance that can't estimate, and have the good market and
developing foreground
Firstly, this paper researched the momentary characteristic of the tyre inside the
course of Foul Wheel Steering, and considers it as the main fact or in the mathematics
model of the 4WS system. Because the model of vehicle tuming that many researchers
used is to base on two wheels vehicle system and two free degrees, which is certain
difference with the actual four whee