Jiang Laiwei, Li Yangtenglong, Zhao Yuyuan, Cen Minyi
Faculty of Geosciences and Engineering, Southwest Jiaotong University, Chengdu 611756, China.
Key Laboratory of High-Speed Railway Engineering of Ministry of Education, Southwest Jiaotong University, Chengdu 610031, China.
Sensors (Basel). 2024 Jul 7;24(13):4403. doi: 10.3390/s24134403.
Track geometry measurements (TGMs) are a critical methodology for assessing the quality of track regularities and, thus, are essential for ensuring the safety and comfort of high-speed railway (HSR) operations. TGMs also serve as foundational datasets for engineering departments to devise daily maintenance and repair strategies. During routine maintenance, S-shaped long-wave irregularities (SLIs) were found to be present in the vertical direction from track geometry cars (TGCs) at the beginning and end of a vertical curve (VC). In this paper, we conduct a comprehensive analysis and comparison of the characteristics of these SLIs and design a long-wave filter for simulating inertial measurement systems (IMSs). This simulation experiment conclusively demonstrates that SLIs are not attributed to track geometric deformation from the design reference. Instead, imperfections in the longitudinal profile's design are what cause abrupt changes in the vehicle's acceleration, resulting in the measurement output of SLIs. Expanding upon this foundation, an additional investigation concerning the quantitative relationship between SLIs and longitudinal profiles is pursued. Finally, a method that involves the addition of a third-degree parabolic transition curve (TDPTC) or a full-wave sinusoidal transition curve (FSTC) is proposed for a smooth transition between the slope and the circular curve, designed to eliminate the abrupt changes in vertical acceleration and to mitigate SLIs. The correctness and effectiveness of this method are validated through filtering simulation experiments. These experiments indicate that the proposed method not only eliminates abrupt changes in vertical acceleration, but also significantly mitigates SLIs.
轨道几何测量（TGMs）是评估轨道平顺性质量的关键方法，因此对于确保高速铁路（HSR）运营的安全性和舒适性至关重要。TGMs还作为工程部门制定日常维护和维修策略的基础数据集。在日常维护期间，发现轨道几何测量车（TGCs）在竖曲线（VC）的起点和终点处，垂直方向存在S形长波不平顺（SLIs）。在本文中，我们对这些SLIs的特征进行了全面分析和比较，并设计了一种用于模拟惯性测量系统（IMSs）的长波滤波器。该模拟实验最终表明，SLIs并非归因于与设计参考相比的轨道几何变形。相反，纵向轮廓设计中的缺陷导致了车辆加速度的突然变化，从而产生了SLIs的测量输出。在此基础上，进一步研究了SLIs与纵向轮廓之间的定量关系。最后，提出了一种在坡度和圆曲线之间添加三次抛物线过渡曲线（TDPTC）或全波正弦过渡曲线（FSTC）的方法，以实现平滑过渡，旨在消除垂直加速度的突然变化并减轻SLIs。通过滤波模拟实验验证了该方法的正确性和有效性。这些实验表明，所提出的方法不仅消除了垂直加速度的突然变化，而且显著减轻了SLIs。
