Results of accelerometer measurements in rail passenger transport vehicles

As part of the project, field research was done to better understand how unbalanced accelerations affect passenger comfort in rail transport and to compare this with passengers’ actual, subjective feelings. Data were collected from different types of rail vehicles, like trains and trams, using common mobile devices with MEMS accelerometer sensors. The research included measuring unbalanced accelerations inside Electric Multiple Units (EMU), Diesel Multiple Units (DMU), and trams. Measurements were taken in cities like Bydgoszcz, Toruń, Olsztyn, and Gdańsk, and on various railway lines, such as lines no. 9, 353, 131, 18, 248, 21, 214, 229, 202, 213, and 250. During the research, the speed of the vehicle, geographical coordinates, unbalanced accelerations in a three-axis reference system, and passengers’ comfort feelings were recorded according to the NMV ISO PN-EN 12299 scale. The final result was a large dataset with over 19 GB of uncompressed data and metadata. These data were processed and saved in .csv, .txt, and .xlsx formats. They were organized into folders by type of transport, measurement name, and file format. Summary data sets were also created, including information like measurement location, track gauges, dates and times of measurements, line and vehicle numbers, measurement station numbers, raw data file names, and the model of the measuring device. Preliminary analysis showed that the travel comfort index calculated according to the PN-EN 12299:2009 standard might differ from passengers’ feelings. Comfort indicators should be adjusted to specific conditions and types of vehicles. Using mobile devices for research might have affected the accuracy of the results. Further research should use calibrated equipment, compare results, and introduce correction factors. It is also worth considering developing a custom Android app for such measurements, based on the experience gained from this project. The research was funded by the MINIATURA_7 grant awarded by the National Science Centre (NCN).本项目开展了实地研究，旨在深入探究不平衡加速度对轨道交通乘客舒适度的影响，并将其与乘客真实的主观感受进行对比。 研究采用搭载微机电系统（MEMS）加速度传感器的普通移动设备，从列车、有轨电车等不同类型的轨道交通工具上采集数据。 本次研究涵盖了对电力动车组（Electric Multiple Units, EMU）、内燃动车组（Diesel Multiple Units, DMU）及有轨电车内部不平衡加速度的测量。测量工作在比得哥什、托伦、奥尔什丁、格但斯克等城市，以及9号、353号、131号、18号、248号、21号、214号、229号、202号、213号、250号等多条铁路线路上开展。 研究过程中，依据NMV ISO PN-EN 12299标准量表，记录了列车车速、地理坐标、三轴坐标系下的不平衡加速度以及乘客的舒适度感受。 最终产出的数据集规模庞大，包含超过19 GB的未压缩原始数据与元数据。所有数据均经过处理后，以.csv、.txt及.xlsx格式存储，并按照轨道交通类型、测量名称及文件格式进行文件夹分类归档。此外还构建了汇总数据集，涵盖测量地点、轨距、测量日期与时间、线路及车辆编号、测量站点编号、原始数据文件名以及测量设备型号等信息。 初步分析结果显示，依据PN-EN 12299:2009标准计算得到的出行舒适度指数，或与乘客的实际感受存在偏差。舒适度指标应针对特定场景与车辆类型进行调整。本研究采用移动设备开展采集工作，可能对结果精度造成影响，因此后续研究应使用经过校准的设备，对结果进行比对并引入修正因子。此外，基于本项目积累的经验，开发专用的安卓（Android）测量应用程序也具有较高的实践价值。 本研究由波兰国家科学中心（National Science Centre, NCN）资助的MINIATURA_7项目基金支持。