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On-Board Detection of Longitudinal Track Irregularity Via Axle Box Acceleration in HSR

Track irregularity detection serves as one of the most essential technologies to interpret the in-service condition of the high-speed railway (HSR) and ensure the comfortability and safety in HSR service. This study newly proposed a novel on-board detection technique integrated with newly developed algorithm for identifying the longitudinal track irregularity to obtain the condition monitoring for further condition based maintenance (CBM). Such on-board detection technique includes data acquisition unit, spatial-time synchronous calibration unit and data processing unit, which can be directly installed in commercial high-speed trains. Via inertial reference method, an algorithm is developed to derive longitudinal irregularity from the acceleration measured in axle box of high-speed train by combining multiple digital filters. A prototype is developed and is installed on a comprehensive inspection train to verify the feasibility and test on multiple HSR lines eventually. The comparison affirms that the detection system has high accuracy and sound repeatability, and certain on-board detection technique enables the real-time online monitoring of track condition.