汽车防抱死制动系统分级智能控制

在分析车辆制动时轮胎与地面接触力学特性的基础上,提出一种用轮速峰值连线来求解参考车速和参考滑移率的方法.为了解决汽车防抱死制动系统(ABS)在各种条件下复杂的控制问题,设计出一种由运行控制、参数校正和组织协调构成的分级智能控制系统.在运行控制级,给出参考滑移率误差的目标轨迹.建立特征模型、控制模态集和推理规则集,以此设计出基于参考滑移率的仿人智能控制器.在参数校正级,为了弥补只针对参考滑移率控制的不足,用车轮角减速度对仿人智能控制量进行校正.在组织协调级,设计出基于轮减速度和参考滑移率的模糊智能控制器来自动辨别制动时的路面信息,给出四轮制动的协调控制规则.运用Matlab进行汽车ABS的仿人智能控制系统研究,搭建出汽车ABS全车测控系统,参照国际标准,在不同条件下进行道路试验.试验结果表明,相对于逻辑门限控制,ABS分级智能控制具有良好的制动平稳性和自适应性,可提高控制精度,是一种有效的新的ABS控制方法.

HIERARCHICAL INTELLIGENT CONTROL OF AUTOMOBILE ANTI-LOCK BRAKING SYSTEM

A new method using difference of the peak values of wheel velocity to calculate reference vehicle velocity and ref- erence slip ratio is proposed,which is based on the analyses of the mechanics characteristics between the tire and the road when the vehicle is being braked.To solve complex control problem of automobile anti-lock braking system(ABS)in dif- ferent conditions,a hierarchical intelligent control(HIC)system is investigated.It includes running control level,parameters adjusting level and organization coordination level.According to the instantaneous performance index of reference slip ratio,a human-simulation intelligent controller(HSIC)aiming at con- trolling reference slip ratio is designed in running control level. The characteristic model,control modes set and reasoning rules set are built.In parameter adjusting level,to decrease the deft- ciency of reference slip ratio control,a method is pointed that modifies the calculation values of HSIC pursuant to wheel an- gle deceleration.In coordination level,a fuzzy intelligent con- troller with the inputs of wheel deceleration and reference slip ratio is designed to implement road automatic identification. Then four wheels braking coordination control rules are also given.The simulation on HIC system of ABS is developed with Matlab.An automotive ABS test and control system is con- structed and the road tests under different conditions are com- pleted according to the international standards.Compared to traditional logic gate control,test results show that the HIC is an effective new ABS control method with better braking sta- bility,adaptiviness and control accuracy.