主动前轮转向系统与防抱死制动系统协调控制

针对汽车转向制动工况,研究汽车主动前轮转向系统(AFS)和防抱死制动系统(ABS)的协调控制;建立七自由度整车模型、前轮主动转向系统模型、防抱死制动系统模型以及轮胎模型,设计了转向系统控制器和制动系统控制器,以及两子系统的协调控制器,并对提出的控制策略进行了仿真分析和对比验证。仿真结果表明:在转向制动工况下,与独立控制系统相比较,协调控制系统能够在保持车辆制动稳定性的同时缩短制动距离,充分发挥两子系统的优势,进一步了提高汽车的操纵性和安全性。     

乘用车电动助力转向系统建模与设计

提出了汽车电动助力转向系统的控制日标,并分析总结出不同工况下的控制策略.建立了电动助力转向系统模型,结合电动助力转向系统特性设计了带有串联校正的PID控制器.通过在助力控制策略下的仿真,验证了助力特性、校正方案和转向盘转角估算算法的正确性.试验结果表明,系统实际助力特性与理想助力特性之间基本一致.     

电动助力转向系统控制的台架试验研究

提出了将基于模糊神经网络的PID控制策略用于电动助力转向系统中助力电机的控制。设计了电动助力转向试验台，并进行了电动助力转向系统的台架试验。试验结果证明，采用模糊神经网络控制器确定目标电流，并使用PID反馈控制器跟踪目标电流的控制策略是十分有效的，能显著提高汽车的转向轻便性和灵敏性。     

卡罗拉轿车电动助力转向系统的结构与检修

现代汽车的助力转向系统,有液压式和电动式两种类型,绝大多数汽车采用液压助力转向.卡罗拉轿车装备的是目前较先进的电动助力转向系统,简称"EPS".由于电动助力转向系统具有提升全车的经济性、使汽车转向控制更加灵活、控制响应快和结构简单等一系列优点,所以在现代汽车上越来越多地使用.     

基于ABS的汽车能量再生制动集成控制研究

提出一种基于ABS系统的能量再生制动集成控制方式,将汽车再生制动融合到ABS制动系统中,再生制动电机参与防抱死控制,制动中在保证制动安全前提下尽可能优先采用再生制动.并设计了基于TMS320C6713芯片的集成控制器.相关试验表明,该控制方式不仅能实现再生制动与液压ABS制动系统协调兼容,提高能量回收率,还可以充分利用电机制动响应快的优点,更好地实现车辆制动防抱死控制.     

汽车电动助力转向系统的研究现状及发展趋势

文章介绍了电动助力转向系统的基本结构和工作原理,对目前的助力控制、回正控制、阻尼控制等控制策略进行了分析,对控制器和电动助力转向系统的稳定性进行了分析,并对电动助力转向系统的发展趋势提出了一些展望。     

电动助力转向（EPS）技术研究

电动助力转向系统是一种新型的汽车转向系统,具有以往任何助力转向系统所不具备的助力效果和车速感应能力,其核心部件电控单元能根据车速和方向盘操控力矩的不同决定是否助力以及助力的大小.电动助力转向技术已目趋成熟,它有取代液压动力转向的趋势,是一项紧扣当今汽车发展主题,符合未来汽车发展趋势的高新技术.本文在介绍国内外汽车电动助力转向的发展现状,详细分析了电动助力转向的工作原理,从分析电动助力转向系统的关键技术入手,围绕电动助力转向系统的结构分析和控制策略两大关键技术展开研究分析,为汽车电动助力的发展奠定基础.     

ABS防抱死制动系统故障检测

ABS是一种具有防滑且防锁死等优点的汽车安全控制系统,既有普通制动系统的制动功能,又能防止车轮锁死,使汽车在制动状态下仍能转向,保证汽车的制动方向稳定性,防止产生侧滑和跑偏,是目前汽车领域最先进和制动效果最佳的制动装置.ABC防抱死制动系统,通过安装在车轮上的传感器发出车轮将被抱死的信号,控制器指令调节器降低该车轮制动缸的油压,减小制动力矩,文章对ABS防抱死制动系统的组成和原理进行分析,并对该系统的故障检测技术进行探讨.     

汽车防抱死制动系统H_∞控制与PID控制的比较研究

控制方法是汽车防抱死制动系统的核心技术。为了提高ABS系统的鲁棒性能,在建立汽车防抱死制动系统数学模型的基础上,设计了H∞控制器,在Matlab/Simulink平台上对基于H∞控制器的ABS系统进行了动态仿真,并与基于传统PID控制器的ABS系统进行对比。通过对仿真结果进行比较发现,PID控制和H∞控制都能使ABS系统获得较好的制动性能;H∞控制响应迅速、具有优秀的稳定性和鲁棒性,总体控制效果优于PID控制。     

汽车电动助力转向系统助力性能的仿真研究

助力性能是评价汽车电动助力转向系统性能的重要指标，助力性能直接关系到汽车转向操作的安全性。以电动助力转向系统的跟踪性能和稳定性为控制系统设计目标，将经典控制理论的PID控制与虚拟样机技术相结合应用于电动助力转向控制系统的设计，创建了电动助力转向系统机电一体化仿真模型。计算机仿真结果证实．所设计的PID控制算法使电动助力转向系统具有良好的跟踪性能和稳定性，仿真结果为电动助力转向控制系统的设计提供了依据。     

汽车防抱死制动系统的自抗扰控制研究

汽车防抱死制动系统（Anti-lock Braking System,ABS）的作用是确保汽车制动时行驶方向的稳定性、可靠性,但是目前仍存在非线性、时变性以及参数不确定性等问题。为保证汽车制动行驶过程中的操纵稳定性和安全性,进一步实现各工况下防抱死制动系统的优化控制,以影响整车稳定的变量滑移率为研究对象,分析所设计策略的控制效果。搭建汽车动力学模型、制动系统模型、轮胎模型和滑移率模型等主要模型,设计基于滑移率的ABS二阶非线性自抗扰控制器。运用MATLAB/Simulink软件对基于自抗扰控制（Active Disturbance Rejection Control,ADRC）的ABS制动过程和基于模糊PID控制的ABS制动过程进行仿真,对比研究最佳滑移率、载荷、水泥-冰对接路面、扰动等对制动过程中的轮速、车速以及滑移率等动态性征反映的稳定性和抗扰能力的影响,同时研究其对最终制动距离和最终制动时间反映的制动性能的影响。最后,将自抗扰控制器和模糊PID控制器装配于试验车辆的ABS,进行水泥路面和冰-水泥对接路面制动过程的实车试验。研究结果表明：基于二阶非线性自抗扰控制算法的ABS制动的最终制动距离和最终制动时间更短、制动效果更优,制动过程中的轮速、车速和滑移率在响应速度、稳定性和抗扰能力等方面均更佳;试验结果与仿真结果吻合,证明了仿真模型及其仿真结果的可行性和正确性。     

2018版C-NCAP及对汽车电子系统的新要求

介绍2018版的新车评价规程(C-NCAP)对主动安全系统的电子控制系统提出的新要求。基于智能交通的汽车自动紧急制动系统是先进安全技术的一项重要内容,本文着重介绍自动紧急制动系统的功能、分层架构前端传感系、底层执行系统、系统架构、AEB控制策略及AEB与ABS协调控制。最后还介绍新版规则对纯电动汽车/混合动力汽车(EV/HEV)的测试项。     

A Sliding Mode Controller for Wheel Slip Ratio Control System

A sliding mode controller has been developed for a wheel slip ratio control system for commercial vehicles with sluggish braking actuators to replace conventional if-then rule-like ABS control laws. New techniques overcome the tendency of sliding mode controllers to chatter. Computer simulation (hardware-in-the-loop simulation) and actual vehicle tests verified the effectiveness of this method to suppress chattering and keep the wheel slip ratio in a desirable range during braking on low-friction road surfaces.     

Improved Vehicle Performance Using Combined Suspension and Braking Forces

This work presents a preliminary investigation into the integration of particular subsystems of an automobile's chassis. The specific focus of this research is the integration of Active Suspension components with Anti-Lock braking (ABS) mechanisms. The performance objective for the integrated approach is defined as a reduction in braking distance over just anti-lock brakes. Several models, of varying degrees of complexity, are presented to determine the effect of modeling accuracy on the potential performance improvement. In the most detailed model, a four degree of freedom Half Car vehicle model is developed along with models for a hydraulic Active Suspension and an ABS system. For both subsystems, actuator dynamics are included. The tire-road interface is modeled using the Magic Formula tire model. Individual controllers are developed for the subsystems and a governing algorithm is constructed to coordinate the two controllers. Simulations of the integrated controller and an ABS system, for each system model, demonstrate a significant increase in performance.     

Active front wheel steering model and controller for integrated dynamics control systems

We report a model and controller for an active front-wheel steering (AFS) system. Two integrated dynamics control (IDC) systems are designed to investigate the performance of the AFS system when integrated with braking and steering systems. An 8-degrees-of-freedom vehicle model was employed to test the controllers. The controllers were inspected and compared under different driving and road conditions, with and without braking input, and with and without steering input. The results show that the AFS system performs kinematic steering assistance function and kinematic stabilisation function very well. Three controllers allowed the yaw rate to accurately follow a reference yaw rate, improving the lateral stability. The two IDC systems improved the lateral stability and vehicle control and were effective in reducing the sideslip angle.     

Nonlinear tire-road friction control based on tire model parameter identification

A hierarchical control structure is a more suitable structural scheme for integrated chassis control. Generally, this type of structure has two main functions. The upper layer manages global control and force allocation, while the bottom layer allocates realized forces with 4 independent local tire controllers. The way to properly allocate these target forces poses a difficult task for the bottom layer. There are two key problems that require attention: obtaining the nonlinear time-varying coefficient of friction between the tire and different road surfaces and accurately tracking the desired forces from the upper layer. This paper mainly focuses on longitudinal tire-road friction allocation and control strategies that are based on the antilock braking system (ABS). Although it is difficult to precisely measure longitudinal tire-road friction forces for frequently changing road surface conditions, they can be estimated with a real-time measurement of brake force and angular acceleration at the wheels. The Magic Formula model is proposed as the reference model, and its key parameters are identified online using a constrained hybrid genetic algorithm to describe the evolution of tire-road friction with respect to the wheel slip. The desired wheel slip, with respect to the reference tire-road friction force from the top layer, is estimated with the inverse quadratic interpolation method. The tire-road friction controller of the extended anti-lock braking system (Ext-ABS) is designed through use of the nonlinear sliding mode control method. Simulation results indicate that acceptable modifications to changes in road surface conditions and adequate stability can be expected from the proposed control strategy.     

多轴分布式电驱动车辆电液复合制动控制研究

针对多轴分布式电机驱动车辆电液复合制动中易出现的车辆制动抖动问题,提出了一种建压阶段电机制动力修正策略和一种基于前馈-反馈的协调控制策略,分别在建压阶段和其他阶段通过协调复合制动力来解决制动抖动的问题。针对防抱死控制系统与电机制动系统共同作用时的制动矛盾,提出了一种基于PID 控制的ABS控制策略,主要通过改变电机制动力来解决制动矛盾的问题。通过TruckSim、Matlab/Simulink及AMESim联合仿真验证,制动冲击度在建压阶段下降了 20.66%,在电机退出阶段下降了 92.59%,驾驶感觉得到明显改善。而 ABS控制策略也可在保证理想滑移率的同时完成制动能量回收;结合整车制动试验,表明协调控制策略在保证制动效果良好的同时实现了制动能量回收,效果显著。     

Improvement of drivability and fuel economy with a hybrid antiskid braking system in hybrid electric vehicles

When braking on wet roads, Antilock Braking System (ABS) control can be triggered because the available brake torque is not sufficient. When the ABS system is active, for a hybrid electric vehicle, the regenerative brake is switched off to safeguard the normal ABS function. When the ABS control is terminated, it would be favorable to reactivate the regenerative brake. However, recurring cycles from ABS to motor regenerative braking could occur. This condition is felt to be unpleasant by the driver and has adverse effects on driving stability. In this paper, a novel hybrid antiskid braking system using fuzzy logic is proposed for a hybrid electric vehicle that has a regenerative braking system operatively connected to an electric traction motor and a separate hydraulic braking system. This control strategy and the method for coordination between regenerative and hydraulic braking are developed. The motor regenerative braking controller is designed. Control of regenerative and hydraulic braking force distribution is investigated. The simulation and experimental results show that vehicle braking performance and fuel economy can be improved and the proposed control strategy and method are effective and robust.     

Experimental investigations on continuous regenerative anti-lock braking system of full electric vehicle

Functions of anti-lock braking for full electric vehicles (EV) with individually controlled wheel drive can be realized through conventional brake system actuating friction brakes and regenerative brake system actuating electric motors. To analyze advantages and limitations of both variants of anti-lock braking systems (ABS), the presented study introduces results of experimental investigations obtained from proving ground tests of all-wheel drive EV. The brake performance is assessed for three different configurations: hydraulic ABS; regenerative ABS only on the front axle; blended hydraulic and regenerative ABS on the front axle and hydraulic ABS on the rear axle. The hydraulic ABS is based on a rule-based controller, and the continuous regenerative ABS uses the gain-scheduled proportional-integral direct slip control with feedforward and feedback control parts. The results of tests on low-friction road surface demonstrated that all the ABS configurations guarantee considerable reduction of the brake distance compared to the vehicle without ABS. In addition, braking manoeuvres with the regenerative ABS are characterized by accurate tracking of the reference wheel slip that results in less oscillatory time profile of the vehicle deceleration and, as consequence, in better driving comfort. The results of the presented experimental investigations can be used in the process of selection of ABS architecture for upcoming generations of full electric vehicles with individual wheel drive.     

ABS“V模式”开发中的快速控制器样件制作和硬件在环仿真的研究

分析了制动过程的车辆动力学特性,建立了车辆系统模型和ABS控制器模型.遵循"V模式"开发流程,在Matlab/Simulink和dSPACE开发环境下实现了汽车ABS控制系统的快速样件制造和硬件在环仿真.