Condition monitoring of railway tracks using compact size on-board monitoring device

This paper summarizes a new development of a compact size on-board device for condition monitoring of railway tracks and the monitoring software. Track irregularities are estimated from a vertical and lateral acceleration and roll rate of a car body. A GPS system and a map-matching algorithm are used to pinpoint the location of faults on tracks. The device is driven by Li-ion battery for 6 hours or outside power source. Accelerometers, rate gyroscope and GPS were redesigned to give higher performance. One can add a microphone outside if a condition monitoring of rail corrugation is necessary. Collected data are usually kept in an inside un-volatility memory (SSD) or a SD card. Communication unit transfers the collected data to a data server via cellular phone. The monitoring software provides a function to detect track irregularities using RMS of the carbody acceleration. It also provides a function to analyse in time-frequency domain using continuous wavelet transform. A monitoring experience in a local railway line showed that the system is effective for practical use.