基于协调一致性的半挂汽车列车制动性能研究

半挂牵引车和半挂车组成的半挂汽车列车是最为常见的公路运输工具。根据实际运输需求,半挂牵引车与半挂车之间可随机连接,极大程度地提升了运输效率,降低了运输成本。半挂汽车列车的道路行驶安全也不容忽视,车辆的制动协调一致性对于其安全性能有着巨大影响。本文依据GB 12676—2014《商用车辆和挂车制动系统技术要求及试验方法》的相关要求,基于协调一致性,规定了相应的制动兼容带,设计了一套气压调节装置,通过法规试验对半挂汽车列车的制动性能展开研究,为企业的研发认证提供参考。     

关于牵引座与牵引销使用中存在问题的几点看法

半挂牵引车与半挂乍通过安装在牵引车上的牵引座与安装在半挂车上的牵引销相连接，组成半挂汽车列车。因此，在半挂汽车列车中牵引座与牵引销是两个十分重要的部件，其组合     

关于影响挂车自动制动响应时间的简单探讨

国内牵引车和挂车采用气压制动系统,其系统压力为0.85MPa,挂车在常规制动、紧急状况下的自动制动都可以通过牵引车来控制。挂车制动气源来自牵引车驻车回路,挂车与牵引车是通过两条管路进行连接的,其中红色管路为供能管路常有气,黄色管路为控制管路控制着挂车的制动和紧急状况下的自动制动。挂车分为半挂车和全挂车,本文讨论的是半挂车,对应的牵引车为半挂牵引车。     

挂车轮胎非正常损耗的原因分析及对策

挂车轮胎,是指用于半挂车或全挂车上的轮胎,挂车与半挂牵引车或全挂牵引车组成汽车列车;轮胎的非正常损耗,是指轮胎未能行驶到额定里程就报废的损耗。     

半挂汽车制动性能台试与路试检验的比较分析

<正>半挂汽车是公路货运的主要运输车型,它装载量大,运输效率高,经济性好。半挂汽车由半挂牵引车和半挂车组合而成,因车身长、车轴多,牵引车和挂车组合又不固定,常会将某牵引车和几辆半挂车组成多辆半挂列车,用甩挂方式提高运输效率。这种随时随地就能组合的半挂汽车的制动性能,能否确保安全行车是车辆检测的新课题。即使牵引车和挂车各自的制动性能都良好,但新组合的半挂汽车制动性能也未必都能符合安全行驶要求,这在一些半挂汽车     

汽车挂车的选型与设计(二)

二、挂车车型的分类及选择牵引汽车(载货牵引车、压重牵引车、鞍式牵引车)和挂车(包括全挂和半挂车)组成汽车列车,其挂车根据不同的运输对象和要求有多种型式,按其牵引方式和结构特点大致可分为:     

半挂汽车列车转弯制动试验方法研究

转弯制动性能对半挂汽车列车的制动安全有重大影响,针对我国目前半挂汽车列车转弯制动试验标准缺失,传统的单车试验设备不适用于半挂汽车列车等问题,本文中从试验系统搭建、系统安装方式和试验方法与评价等方面对半挂汽车列车转弯制动试验进行了探索性研究。结果表明:半挂汽车列车转弯制动过程中侧向加速度、制动减速度、横摆角速度和牵引车的俯仰角随车速的升高而增加。建议半挂汽车列车转弯制动试验中车速不超过30km/h,转弯半径不小于25m。     

全挂汽车列车主动转向建模分析

汽车列车在公路交通运输中起着举足轻重的作用,为公路货运量流通提供高性价比的运输方式,贴合当代发展需求。随着汽车列车使用需求日益增长,其不足之处也日益凸显,因而提高汽车列车的运输效率及安全性,保证汽车列车长远发展势在必行。现基于一种双杆式全挂汽车列车提出主动转向控制研究方法,使车辆进行弯道行驶时,在主动转向装置和主动转向控制方法的双重作用下实现挂车对牵引车的转向运动进行主动跟随。文章建立连接装置、电液控制部分以及全挂车模型,仿真结果证明该转向系统具有稳定性。     

解码挂车牵引销及牵引装置的使用与维修

随着汽车物流拖挂运输的发展,汽车半挂列车也发展很快,它具有装载质量大、转弯灵活,燃油消耗低、经济效益高等优点.半挂车牵引系统在工作过程中受到向前和向后、横向摇摆力矩、垂直方向和向上等多种载荷作用,工况比较复杂.半挂车与牵引车连接全是靠牵引销及牵引装置了(也称牵引鞍座总成),它与主车牵引座相连接,还承受所有牵引力,是半挂、全挂车中应用的一个很重要的金属标准零部件. 1 挂车牵引装置的功用和类型 挂车牵引装置的功用:一是联接;二是牵引;三是支承.对半挂汽车列车来说,牵引装置还须承受半挂车的部分质量,并传递给牵引车.     

应用虚拟样机技术进行半挂汽车列车制动动力学分析

将虚拟仿真软件ADAMS应用到半挂汽车列车制动动力学研究中，建立了半挂汽车列车整车26自由度（DOF）动力学模型，对半挂汽车列车直线制动及转弯制动进干亍了仿真分析。通过仿真分析发现，在车辆无ABS转弯制动时，即使按照理想抱死顺序实施制动，半挂车也会出现瞬态“甩尾”的危险工况。     

机场拖车制动系统的改进方案探析

以现有的机场拖车为原型,针对制动时存在的问题,提出了一些改进建议和想法,使拖车在牵引车制动时能利用自身的惯性力自行制动,减少制动距离和时间,以符合当前机场大运货量对制动距离的要求。     

基于Simulink/Stateflow的汽车ABS混合建模与仿真

汽车防抱死制动系统(ABS)是一种很关键的汽车主动安全技术。本文采用基于有限状态机的系统仿真方法,采用Simulink和Stateflow模块混合建模,对ABS模型中的连续系统和离散系统进行仿真。仿真结果表明,该混合仿真系统能比较真实地反映汽车ABS系统的实际工作过程,显著缩短制动距离,提高安全性。     

新型电磁制动器的挂车防抱死控制及其仿真

对于使用一种新型电磁制动器的挂车,针对其特点应用模糊控制方法,以滑移率为控制目标,对使用车辆进行了防抱死控制,并使用Matlab中的Simulink工具箱对制动过程进行了仿真。仿真结果表明在使用这种新型电磁制动器的车辆防抱死过程中,模糊控制具有良好的控制效果。     

Closed-Loop Directional Stability of Car-Trailer Combinations in Straight-Line Motion

This work focuses on the interaction between a driver and a car-trailer combination. A model characterizing human operator behavior in regulation task is employed to study directional stability of the overall system. The vehicle-trailer model retains nonlinear cornering force and other kinematic nonlinearities. Linear stability of the straight line motion is analyzed by the application of Routh-Hurwitz criteria and stability boundaries in parameter space are constructed by setting appropriate Hurwitz determinant to zero. It is shown that two types of transition in stability are possible in the driver/car-trailer system. They correspond to one pair or two pairs of complex conjugate eigenvalues crossing the imaginary axis simultaneously. The implications in terms of resulting motions for the nonlinear system are also discussed. It is shown that stabilization of the combination can be achieved by adding a passive controller at the articulation point. Articulation damper turns out to be a more useful device for controlling trailer oscillations instability although a combination of damper and torsional spring would be a more ideal solution.     

Closed-Loop Directional Stability of Car-Trailer Combinations in Straight-Line Motion

SUMMARY

This work focuses on the interaction between a driver and a car-trailer combination. A model characterizing human operator behavior in regulation task is employed to study directional stability of the overall system. The vehicle-trailer model retains nonlinear cornering force and other kinematic nonlinearities. Linear stability of the straight line motion is analyzed by the application of Routh-Hurwitz criteria and stability boundaries in parameter space are constructed by setting appropriate Hurwitz determinant to zero. It is shown that two types of transition in stability are possible in the driver/car-trailer system. They correspond to one pair or two pairs of complex conjugate eigenvalues crossing the imaginary axis simultaneously. The implications in terms of resulting motions for the nonlinear system are also discussed. It is shown that stabilization of the combination can be achieved by adding a passive controller at the articulation point. Articulation damper turns out to be a more useful device for controlling trailer oscillations instability although a combination of damper and torsional spring would be a more ideal solution.     

基于ARM7的汽车底盘系统分层式协调控制试验研究

采用分层协调控制策略,进行了汽车电动助力转向系统和防抱死制动系统集成控制的研究.分别设计了底层控制器和上层协调控制器,底层控制器包括电动助力转向和防抱死制动两个单独的控制器,用以执行各子系统的控制任务;上层协调控制器则对两系统进行协调分析,并及时修改底层控制决策.试验结果表明,自行开发的底层控制器逻辑正确,上层协调控制器能够较好地协调两系统问的矛盾,解决了汽车在转向过程中施加紧急制动时车辆的操纵稳定性和平顺性变差的间题,使整车综合性能得到提高.     

A closed-loop dynamic simulation-based design method for articulated heavy vehicles with active trailer steering systems

This paper presents a closed-loop dynamic simulation-based design method for articulated heavy vehicles (AHVs) with active trailer steering (ATS) systems. AHVs have poor manoeuvrability at low speeds and exhibit low lateral stability at high speeds. From the design point of view, there exists a trade-off relationship between AHVs’ manoeuvrability and stability. For example, fewer articulation points and longer wheelbases will improve high-speed lateral stability, but they will degrade low-speed manoeuvrability. To tackle this conflicting design problem, a systematic method is proposed for the design of AHVs with ATS systems. In order to evaluate vehicle performance measures under a well-defined testing manoeuvre, a driver model is introduced and it ‘drivers’ the vehicle model to follow a prescribed route at a given speed. Considering the interactions between the mechanical trailer and the ATS system, the proposed design method simultaneously optimises the active design variables of the controllers and passive design variables of the trailer in a single design loop (SDL). Through the design optimisation of an ATS system for an AHV with a truck and a drawbar trailer combination, this SDL method is compared against a published two design loop method. The benchmark investigation shows that the former can determine better trade-off design solutions than those derived by the latter. This SDL method provides an effective approach to automatically implement the design synthesis of AHVs with ATS systems.     

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.     

Front-Rear Interaction of a Pitch-Plane Truck Model

Results from a previously reported experimental study on heavy articulated vehicles show that the choice of tractor unit strongly affects the dynamic tyre forces generated by the trailer axles, but the choice of trailer unit does not strongly affect the tyre forces generated by the tractor axles. These results have implications for assessing the road-friendliness of tractor and trailer units. The objectives of the work described in this paper are to understand the dynamic interaction between the tractor and trailer unit, and to identify the conditions for which strong interaction exists. A mathematical model with two degrees of freedom is used to simulate the pitch-plane dynamics of an articulated vehicle. Three idealized vehicles are investigated and three conditions for strong dynamic interaction are identified. It is thought that these conditions are likely to exist in a large proportion of heavy trucks.     

轮胎气压/漏气检测报警系统

汽车轮胎气压，漏气检测、报警系统是专门自动检测汽车轮胎的压力，同时判断轮胎是否漏气的一种装置。在未来汽车上加装轮胎压力监测系统（TPMS）是必然的发展趋势。着重介绍了实现此系统的电路设计和相关的技术问题。此系统是由一个主机，多个从机组成的分布式系统。每个轮胎配置一个从机，由无线通讯方式把轮胎的压力值、是否漏气等信息传给主机．而且从机的功耗非常低。