Co-operative control for regenerative braking and friction braking to increase energy recovery without wheel lock

This paper presents a regenerative braking co-operative control algorithm to increase energy recovery without wheel lock. Considering the magnitude of the braking force available between the tire and road surface, the control algorithm was designed for the regenerative braking force at the front wheel and friction braking force at the rear wheel to be increased following the friction coefficient line. The performance of the proposed regenerative braking co-operative control algorithm was evaluated by the hardware in the loop simulation (HILS) with an electronic wedge brake on its front wheels and an electronic mechanical brake on its rear wheels. The HILS results showed that a proper braking force on the front and rear wheels on a low μ road prevented the lock of the front wheels that was connected to the motor, and maintained the regenerative braking and increased energy recovery.     

制动器台试减速度评定及制动衬片摩擦系数允差的确定

本文分析了制动器台试减速度允差评定方法，为了有效制动和改善轿车制动稳定性，讨论了摩擦材料的摩擦系数与制动减速度和前后制动分配比的关系，根据设计要求之制动减速度和制动力分配比，提供摩擦系数计算方法和顺序，用于合理确定台试时的摩擦系数允差，本文可供制动器设计和摩擦材料选用作参考。     

汽车高速化给维修业带来的新要求

随着汽车工业的发展和高速公路的普及，汽车的速度越来越来高，汽车在前轮定位，制动系以及轮胎等方面也发生了相应的变化，例如车轮外倾角由正值变为负值，前轮前束出现负值，前轮制动力大于后轮制动力，前轮主销内倾角增大等，这些变化在维修时应特别注意。     

摩擦材料摩擦特性对轿车前,后制动力之比的影响

本研究了摩擦材料摩擦特性对轿车（盘式），后（鼓式）制动器制动力之比的影响。根据对前，后制动器部总成大量的测功器试结果，计算并绘出前，后制动之比值随制动管路压力，车速，制动温度的变化关系曲线，并与设计作了对比分析，讨论了它对轿车制动稳定性的影响，为制动性能计算，制动器设计和制动衬片摩擦材料的选配提供依据和参考，从而保证了轿车的制动稳定性。     

基于整车道路测试的几次ABS事故分析

分析了几次ABS测试不合格的试验数据,指出轮速差异过大是造成ABS不合格的主要原因。主要体现为两方面:左右轮速差异对车辆横摆有不利影响,易造成车辆滑出规定的车道宽度;前后轮速差异中的后轮过度制动则会恶化车辆的制动稳定性,易造成甩尾等严重事故。根据积累的各种数据和驾驶员主观感受,提出整车道路测试时的风险评估方法,并给出几起ABS不合格的改进建议。     

电子控制牵引力调节装置

丰田公司凌志ＬＳ４００型１９８０所型轿车装用电子控制牵引力调节有完全调节发动机的扭矩和后驱动轮的制和，并根据路面情况给出一个最佳的驱动力，它主要由制动主继电器，前轮速度传感器，牵引力调节系统执行器等１８个零部件组成，对各零部件的结构和功用进行了详细地介绍。     

汽车列车电控制动系统制动力分配的控制算法

为汽车列车提出了一种基于滑移率的电控制动系统制动力分配算法,即根据不同情况,使牵引车后轮和半挂车车轮的目标滑移率随牵引车前轮滑移率而变化.运用Matlab/Simulink和Trucksim软件进行列车在高附着和低附着路面上行驶的联合仿真,结果表明该算法能缩短汽车列车的制动距离,提高了制动稳定性.     

前后车轮制动器制动力矩的分配

探讨了前后车轮制动器力矩分配对轮式机械制动性能的影响,就如何确定合理的前后轮制动器的分配比值进行了分析,最后确定出了合理的前后轮制动力距.     

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.     

反力式制动试验台加载能力与检验结果真实性的分析

利用反力式制动试验台对前、后轮的加载能力进行了分析，并得出如下结论：（1）因存在系统的微观自激振动，致使滚筒对车轮的加载能力在一定范围内不停地波动；（2）加载能力一般不低于轴荷的60％，对于后轮行车制动力的检验，试验台加载能力的下限值可能低于60％；（3）为使后轮驻车制动力检验的加载能力不低于整车重力的20％，试验台应设置限制车辆后移的辅助设施，以提高驻车制动力的加载能力。     

结构与使用参数对液罐汽车制动特性影响的研究

本文研究液罐汽车在减载、直线制动行驶时,液体货物质心位置变化对制动性能的影响。文中建立了力学和数学模型,分析研究主要结构和使用参数对制动距离、制动时间和前、后轮抱死间隔时间的影响。在不同装载条件下对罐中双隔板的设计位置进行了优化,证明安装双隔板比安装单隔板对改善制动性能有更好的效果。并通过试验进行了验证。     

Effect of the front and rear weight distribution ratio of a Formula car during maximum-speed cornering on a circuit

Because Formula cars are lighter than ordinary cars, the optimal settings for this type of car are thought to be different from those of a ordinary car. The front and rear weight distribution ratio of a vehicle is an important parameter that exerts a significant influence on critical cornering. The tendency of a ordinary car to under-steer during critical cornering is determined by the front and rear weight distribution ratio of the vehicle. Specifically, when the front of an ordinary FR (front-engine, rear wheel drive) vehicle is slightly heavier than the rear, the car tends to understeer during critical cornering. However, the optimal weight distribution ratio for critical cornering is not obvious for a formula car because of its lightness. This observation was investigated using a driving course similar to a real driving course to perform a maximum speed cornering simulations. It was found that a front to rear weight distribution ratio of 40:60 resulted in the fastest lap time. This ratio also gave the best results in the maximum-speed driving experiment performed using a driving simulator. Moreover, the maximum lateral acceleration during turning, the driving force, and the load movement of the inside and outside wheels was calculated using experimental driving force data and the concept of a tire friction circle. As a result, driving mechanics have been determined for a vehicle having a front/rear weight distribution ratio of 40:60 while traveling at maximum speed.     

轮式铣刨机电辅助驱动系统速度匹配分析

以轮式铣刨机为研究对象，针对前桥驱动牵引力不足的情况进行后轮电辅助驱动，在对铣刨机辅助驱动运动学研究的基础上，设计了电辅助驱动速度匹配策略，建立了该铣刨机电辅助驱动的数学模型，并运用Simulink模块对其进行了仿真分析。结果表明：前、后轮速度匹配策略确实可行。     

A Comparative Study of Four Wheel Steering Models Using the Inverse Solution

An inverse solution study of various four wheel steering models is carried out for the purpose of comparison of steering/braking input needed to track a lane change maneuver. Optimal control is used to solve the non-linear inverse problem. Comparisons are made when the vehicle is coasting, when the time required to track the trajectory is minimized with appropriate utilization of brake/traction forces, and in a front wheel lock situation. A rear steering model which produces neutral steering characteristics displayed the best steering behavior with respect to ease of steering.     

大众波罗轿车ABS系统工作原理及故障排除

针对一辆国产上海大众波罗（1.4L）轿车,由于右后轮的轮速传感器安装不到位,造成ABS故障报警灯常亮,汽车紧急制动时,ABS系统不工作,4个车轮全抱死滑移的故障,阐述ABS工作原理,介绍故障排除过程。     

轿车前后轴制动力平衡分布研究

基于大量轿车前后轴制动力实测数据，运用数理统计手段，研究确定国产主要轿车前后轴制动车平衡分布规律及分布参数，进而建立相应车型的前后轴制动力平衡分布计算模型，本文研究对从统计规律上掌握国产轿车前后轴承动力平衡性能和准确地计算相应的分布数值具有十分重要的意义。     

发动机制动工况下汽车制动器摩擦性能分析

建立了基于恒速制动车辆纵向力平衡方程、制动器耗散功率及其温度变化微分方程、管路压力调节等子模型的恒速长下坡汽车制动器摩擦性能分析系统.以两轴中型汽车为例,对前后制动器在不同挡位发动机制动时的温度、制动副摩擦因数、制动力分配及管路压力变化进行了计算.结果表明,在不影响车速情况下,合理使用各挡发动机制动可改善汽车前、后制动器热负荷,减小或避免制动摩擦力矩热衰退,保证汽车下长坡安全行驶.     

前轮转角和车轮制动状态对汽车轨迹模拟的影响

对于碰撞后失去动力的汽车，建立其运动轨迹的计算机模型需要碰撞后汽车的初始速度和前轮转角，制动情况等初始值作为轨迹模型的输入参数，以便观察碰撞发生后的汽车运动情况。分析了碰撞后汽车车轮的受力情况，给出不同初始值情况下的轨迹模拟模型。分析结果得出，车轮在自由状态下，前轮的转角对汽车的运动距离有较大影响；当前轮转角为零时，汽车的质心运动几乎为一条直线；当车轮未完全抱死且前轮转角不为零时，汽车的质心运动为一条曲线。     

Wheel slip control with torque blending using linear and nonlinear model predictive control

Modern hybrid electric vehicles employ electric braking to recuperate energy during deceleration. However, currently anti-lock braking system (ABS) functionality is delivered solely by friction brakes. Hence regenerative braking is typically deactivated at a low deceleration threshold in case high slip develops at the wheels and ABS activation is required. If blending of friction and electric braking can be achieved during ABS events, there would be no need to impose conservative thresholds for deactivation of regenerative braking and the recuperation capacity of the vehicle would increase significantly. In addition, electric actuators are typically significantly faster responding and would deliver better control of wheel slip than friction brakes. In this work we present a control strategy for ABS on a fully electric vehicle with each wheel independently driven by an electric machine and friction brake independently applied at each wheel. In particular we develop linear and nonlinear model predictive control strategies for optimal performance and enforcement of critical control and state constraints. The capability for real-time implementation of these controllers is assessed and their performance is validated in high fidelity simulation.     

新型汽车液压增力制动控制器

为了提高汽车制动效率开发一种汽车液压增力制动控制器（HBI）.它主要由增压缸等组成,串联于汽车制动主缸与前制动轮缸之间,将制动主缸输出压力制动液增压,送往前制动轮缸.同时还将压力制动液直接送往后制动轮缸,实现汽车增压制动,其制动效率高于现有减压分配阀组成的制动系统效率10%以上.对具有HBI系统的制动性能检测表明,HBI可用于多种车型的制动系统中,制动踏板力明显下降100 N左右,制动稳定性明显提高.