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.     

近年我国汽车进口环节税政演变及政策建议

为进一步改进和加强对进口汽车的管理,规范汽车进口秩序,进而带动国内汽车产业的健康发展,文章在广泛收集资料的基础上,采用专家咨询和比较分析等方法,详细介绍了近年我国汽车进口环节税收政策的变化情况,并总结了国外汽车进口环节税收政策的特点。研究表明,目前我国汽车进口环节税收政策已成为政府部门调节汽车产品进口数量和结构的重要手段。但与其他国家,特别是汽车工业发达国家相比,仍存在一些问题。文章在此基础上提出相关政策调整建议,为政府提供决策依据和参考。     

Optimal vibration isolation of a tractor–semi-trailer system

The procedure is presented for the analytical synthesis of optimal vibration isolation of a tractor–semi-trailer system subjected to random excitation coming from the road. A general approach is discussed for a selected vibration isolation criterion. The especially elaborated procedure of complex matrix factorization is applied. The general results are presented by numerical calculations and their graphical illustrations.     

轨道交通区域快线车辆检修修程研究

随着城市轨道交通发展,区域快线对车辆日常维护检修提出新的要求,科学合理的车辆检修标准既能提高列车可靠性和投运率,同时可以避免过度修,节约资源。通过对车辆检修修程的影响因素及目前国内主要轨道交通日常维护及检修修程进行研究,结合在建区域快线项目的特点,提出区域快线车辆检修修程研究成果,为区域快线的建设提供理论依据。     

客车转向垂臂的设计与校核

介绍客车转向系统传动机构中的转向垂臂的设计与校核,并给出范例。     

Lateral dynamics emulation via a four-wheel steering vehicle

In this paper, we examine the lateral dynamics emulation capabilities of an automotive vehicle equipped with four-wheel steering. We first demonstrate that the lateral dynamics of a wide range of vehicles can be emulated, either with little or with no modification on the test vehicle. Then we discuss a sliding mode controller for active front and rear wheel steering, in order to track some given yaw rate and side-slip angle. Analytically, it is shown that the proposed controller is robust to plant parameter variations by±10%, and is invariant to unmeasurable wind disturbance. The performance of the sliding mode controller is evaluated via computer simulations to verify its robustness to vehicle parameter variations and delay in the loop, and its insensitivity to wind disturbance. Finally, the emulation of a bus, a van, and two commercially available passenger vehicles is demonstrated in an advanced nonlinear simulator.     

基于测速与测距技术的汽车安全座椅设计

为提高汽车的正面防撞安全性能,降低甚至避免二次碰撞危害,文章特提出一种新型的汽车安全座椅的设计方案。文章介绍了基于测速与测距技术的汽车安全座椅在功能、结构设计及椅背倾角调节等方面的关键问题,并从基础理论的角度进行了可行性验证,说明该技术能提前预测碰撞危险,并及时采取措施避让,提高了汽车的安全性。     

客车运行安全监控系统

客车运行安全监控系统(TCDS)包括车载安全监控系统、车地无线传输系统和地面联网应用系统3个子系统。车载安全监控系统实现车辆关键设备的监测,采用LonWorks工业现场总线作为实时通信网络,采用2级总线式网络结构。车地无线传输系统将监测报警信息实时传输到地面,选择GPRS作为传输实时信息的无线通信方式,采用无线局域网(WLAN)自动下载过程数据。地面联网应用系统采用远程联网分布数据库,数据传输平台采用JWMQ消息中间件,主要包括电子地图实时监控软件、专家系统软件,针对铁道部查询中心、铁路局监控中心、车辆段监测中心3级中心功能的不同,开发和配置相应的应用软件。TCDS系统经在13个铁路局及其管内车辆段安装和运用,系统运行良好。     

基于MATLAB的某特种车转向轮四连杆机构设计

基于MATLAB对某全轮独立转向特种车辆的转向轮四连杆机构进行了设计,并依据设计结果分析了相关参数的运动轨迹,验证了设计结果的合理性。该方法集设计与优化于一体,简化了四连杆机构的设计过程。     

SX6733GE81城市客车液压助力转向系统的匹配设计

通过分析7m级客车转向系布置及对液压式助力转向系统的匹配计算,阐明转向液压系统参数的选择对整个回路的影响,并最终得出合理的方案.