Theoretical and experimental excitation force spectra for railway-induced ground vibration: vehicle–track–soil interaction,irregularities and soil measurements

Excitation force spectra are necessary for a realistic prediction of railway-induced ground vibration. The excitation forces cause the ground vibration and they are themselves a result of irregularities passed by the train. The methods of the related analyses – the wavenumber integration for the wave propagation in homogeneous or layered soils, the combined finite-element boundary-element method for the vehicle–track–soil interaction – have already been presented and are the base for the advanced topic of this contribution. This contribution determines excitation force spectra of railway traffic by two completely different methods. The forward analysis starts with vehicle, track and soil irregularities, which are taken from literature and axle-box measurements, calculates the vehicle–track interaction and gets theoretical force spectra as the result. The second method is a backward analysis from the measured ground vibration of railway traffic. A calculated or measured transfer function of the soil is used to determine the excitation force spectrum of the train. A number of measurements of different soils and different trains with different speeds are analysed in that way. Forward and backward analysis yield the same approximate force spectra with values around 1 kN for each axle and third of octave.     

新能源汽车遥控驾驶功能分析(英文)

汽车遥控驾驶功能可以提升用户操控便捷性及安全性,本文对汽车遥控驾驶运用场景进行了描述,基于相关新的量产车型对遥控驾驶功能进行了对标分析,得出了遥控驾驶应实现的基本功能及实现该功能所需要的硬件配置,提出了新能源电动汽车遥控驾驶功能系统架构设计方案及功能控制策略,为后续车辆遥控驾驶功能开发提供借鉴和参考。     

飞行汽车的研究发展与关键技术

飞行汽车作为面向城市空中交通和未来出行的新型交通工具,正日益受到汽车和航空领域的重视,成为汽车和航空技术与产业跨界融合的重要发展趋势。该文介绍了飞行汽车的内涵及城市空中交通(UAM)概念的兴起,阐述了飞行汽车早期梦想的探索历程、面向城市空中交通的研究现状,以及未来将在全新智慧出行交通体系下实现大众化汽车“飞”起来的发展趋势;论述了飞行汽车发展的高功率密度电动推进、高升阻比轻质车体和低空飞行智能驾驶等主要性能瓶颈和关键技术;提出了中国飞行汽车的阶段性发展目标和构建汽车与航空跨界融合技术创新体系,以及重点推动城市空中交通和应急救援等领域示范应用的发展建议。     

ISG hybrid powertrain: a rule-based driver model incorporating look-ahead information

According to European regulations, if the amount of regenerative braking is determined by the travel of the brake pedal, more stringent standards must be applied, otherwise it may adversely affect the existing vehicle safety system. The use of engine or vehicle speed to derive regenerative braking is one way to avoid strict design standards, but this introduces discontinuity in powertrain torque when the driver releases the acceleration pedal or applies the brake pedal. This is shown to cause oscillations in the pedal input and powertrain torque when a conventional driver model is adopted. Look-ahead information, together with other predicted vehicle states, are adopted to control the vehicle speed, in particular, during deceleration, and to improve the driver model so that oscillations can be avoided. The improved driver model makes analysis and validation of the control strategy for an integrated starter generator (ISG) hybrid powertrain possible.     

垃圾转运车后门液压系统故障分析

针对在实际生产过程中出现的垃圾转运车后门不能举升和下降的故障现象,通过对液压系统原理图的分析和借助适当的检测工具,按照由简单到复杂的原则,逐一排查可能引起故障的原因,使故障得以快速解决,并提供了一种对故障原因进行分析的思路。     

直线电机车辆集电靴升靴故障分析及改进建议

针对直线电机车辆集电靴正线不能升靴的故障现象,分析了故障发生的原因。从工作原理和作业规程出发,提出加装集电靴人工升靴装置改进建议并优化作业流程。即:在新线车辆设计时增加导电靴升靴功能,对既有车辆不建议进行改造。对于现有列车在正线停放,建议列车保持升靴状态的方法简单可行。     

树脂运输罐式半挂车的结构

介绍了树脂运输罐式半挂车的工作方式和工作流程，整车布置及主要部件结构。     

Heavy duty vehicle rollover detection and active roll control

This paper presents the results of a comprehensive study on heavy-duty vehicle (HDV) roll stability improvement technology. The proposed rollover threat warning system uses the real-time dynamic model-based time-to-rollover (TTR) metric as a basis for online rollover detections. Its feasibility for implementation in a HDV rollover threat detection system is demonstrated through vehicle dynamic simulation studies. The research on the development of a rollover threat detection system is further enhanced in combination with an active roll control system using active suspension mechanism to improve heavy-duty trucks’ roll stability both in the static cornering and in emergency maneuvers. It has been demonstrated that the roll stability of typical heavy-duty trucks has been largely improved by the proposed active safety monitoring and control system.     

地铁车辆接地技术分析

文章主要以上海轨道交通4号线车辆为例,介绍了地铁车辆整车接地的分类和特点,对地铁车辆的接地设计原则进行了分析。     

上海地铁13号线车辆底架线槽与布线设计探究

由于地铁车辆的大部分重要电缆都位于车体下方,电缆的外部环境相当恶劣,为了有效防护电缆以减少安全隐患,在地铁车辆上使用了线槽。在模块化概念深入企业设计与生产理念的现状下,结合上海地铁13号线车辆项目,对线槽设计、布线要求、电磁兼容、有限元分析等进行了分析。