Contents Index Volume 35 and 36

Active safety systems would benefit from tyre force and friction potential information. Different sensor concepts, including, among others, the EU–funded Apollo–project developed tyre sensor based on optical position detection, are being studied. The sensor can measure tyre carcass deflections with respect to the rim. The carcass deflections can be used to calculate tyre forces and they may be exploited in the estimation of friction potential. The waveforms of the sensor signal are illustrated. The vertical and lateral force estimations are presented with unavoidable compensation parts. The tyre sensor measurements were compared to the measurement–vehicle results and good correlations achieved. Continuing activities are concerned with the estimation of friction potential and the detection of aquaplaning.     

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.     

Fault-tolerant control of heavy-haul trains

The fault-tolerant control (FTC) of heavy-haul trains is discussed on the basis of the speed regulation proposed in previous works. The fault modes of trains are assumed and the corresponding fault detection and isolation (FDI) are studied. The FDI of sensor faults is based on a geometric approach for residual generators. The FDI of a braking system is based on the observation of the steady-state speed. From the difference of the steady-state speeds between the fault system and the faultless system, one can get fault information. Simulation tests were conducted on the suitability of the FDIs and the redesigned speed regulators. It is shown that the proposed FTC does not explicitly worsen the performance of the speed regulator in the case of a faultless system, while it obviously improves the performance of the speed regulator in the case of a faulty system.     

高精度模态应变能法结构损伤检测研究

基于摄动理论,通过考虑结构参数修改量高阶项的影响,推导了基于单元模态应变能的结构损伤评估方法;数值仿真结果表明,在结构多种损伤情况下,损伤定位准确、程度评估可靠,具有实际应用价值。     

探地雷达数值模拟及其在隧道检测中的应用

利用时域有限差分(FDTD)方法,对隧道工程检测中常见检测目标进行数值模拟,分析脱空、单层钢筋、双层钢筋等目标体的探地雷达反射信号图像特征,并对隧道检测中的雷达信号图像采用遗传算法进行反演,引入目标相关系数用于反演结果全局寻优,实现对多次反射的压制,降低浅部钢筋反射信号对识别深部目标体的影响。通过对数值模拟结果进行反演,证明该方法理论上的有效性,并结合工程实践中的应用效果,说明该方法的优点与局限性。     

基于渗流场变化的基坑止水帷幕缺陷

止水帷幕存在缺陷一直是基坑工程中的重大风险,若能在基坑开挖前判断出止水帷幕缺陷的位置,便能预先采取加固堵漏措施,可避免基坑开挖时的风险。局部渗漏必然会引起附近渗流场的变化,利用有限元软件ABAQUS分别对缺陷的长度、深度以及土体渗透性与帷幕外侧渗流场分布规律的关系进行研究,得出不同工况下缺陷对渗流场分布的横向和竖向影响范围变化规律,证明了根据流速变化判别缺陷存在及位置、规模的可行性。提出采用声纳法可对土体中渗流场分布进行检测,进而可根据渗流场分布判别出缺陷的规模与位置。通过工程实践,验证了研究结论及声纳法检测技术的准确性,为轨道交通深基坑工程止水帷幕缺陷判别提供指导和借鉴方法。     

基于双T滤波器的城市轨道交通列车电缆绝缘检测方法研究

城市轨道列车车载电缆是其整个电力系统中传输和分配电能以及传输信号控制信息的重要设备,电缆的绝缘状态对列车安全可靠运行有重要影响。传统绝缘检测装置都未考虑到电磁干扰对绝缘检测的影响,列车运行环境中严重的电磁干扰易造成绝缘在线监测系统数据的波动大及工作不稳定的问题,为此提出基于双T滤波器的列车电缆绝缘检测新方法。此方法不仅可以提高电缆绝缘检测精度,而且还可以适应列车复杂噪声信号干扰环境,保证设备稳定运行。     

城市轨道交通车站客流安全检测与应急管理系统

围绕为城市轨道交通车站安全应急管理决策提供技术支持的核心目标,设计和研发面向车站管理人员的城市轨道交通车站客流安全检测系统;深入研究建设和实现系统的相关集成技术及关键保障技术,有效实现客流安全问题的实时自动发现、人工确认,以及应急预案启动、预案实施效果实时跟踪及过程控制,以保障城市轨道交通车站安全事件处理的实时高效性,提高城市轨道交通车站安全管理水平.     

列车纵向冲击的检测与分析

针对列车纵向冲击问题,提出了信号采集与处理方案,设计了一套随车采集和分析系统。文中介绍了系统组成、工作原理及运行过程,初步建立了纵向冲击与旅客乘坐舒适度之间的数学模型,并运用该模型进行了实际演算,取得了预期的效果。     

一种准确检测直线同步电机动子位置的方法

论述了利用长定子同步电机的齿槽检测信号与线性插值法结合来提高直线同步电机动子位置检测精度的方法。分析了这种方法的误差,给出了实现线性插值的2种算法、实现的方案、仿真与实验结果。