Department of Civil and Environmental Engineering, Chung-Ang University, Seoul 06974, Korea.
Advanced Railroad Civil Engineering Division, Korean Research Railroad Institute, Gyeonggi-do 16105, Korea.
Sensors (Basel). 2018 Jul 6;18(7):2182. doi: 10.3390/s18072182.
Dynamic deflection of a railroad sleeper works as an indicator of ballast stiffness, reflecting the health conditions of a ballast track. However, difficulty exists in measuring dynamic deflection of a railroad sleeper by conventional deflection transducers such as a linear variable differential transformer (LVDT) or a potentiometer. This is because a fixed reference point is unattainable due to ground vibrations during train passage. In this paper, a patented signal processing technique for evaluation of pseudo-deflection is presented to recover dynamic deflection of a railroad sleeper using a coupled measurement of acceleration and strain at the concrete sleeper. The presented technique combines high-frequency deflections calculated from double integration of acceleration and low-frequency deflections determined from strains. Validity of the combined deflections was shown by the deflections measured with a camera target on a concrete sleeper, captured by a high-resolution DSLR camera with superb video capturing features and processed by computer vision techniques, such as Canny edge detection and Blob analysis.
铁路轨枕的动态挠度可作为道床刚度的指标，反映道床的健康状况。然而，传统的挠度传感器（如线性可变差动变压器（LVDT）或电位器）在测量铁路轨枕的动态挠度时存在困难。这是因为在列车通过时，由于地面振动，无法获得固定的参考点。本文提出了一种专利信号处理技术，用于评估伪挠度，该技术使用混凝土轨枕上的加速度和应变的耦合测量来恢复铁路轨枕的动态挠度。所提出的技术结合了从加速度的双重积分计算得到的高频挠度和从应变确定的低频挠度。通过使用具有出色视频捕获功能的高分辨率数码单反相机拍摄的混凝土轨枕上的相机目标测量的挠度，并通过计算机视觉技术（如 Canny 边缘检测和 Blob 分析）进行处理，验证了组合挠度的有效性。
