Temporal Subtraction Processing Of Derailment Coefficient Collected With The Monitoring Bogie

A typical index to evaluate the running safety of railway vehicles is the derailment coefficient. Recently, a new type of monitoring bogie which monitors derailment coefficients during commercial operations has been developed. In order to perform predictive maintenance of tracks utilizing the new monitoring bogie, temporal subtraction processing, which is commonly used in medical fields, seems effective to identify yearly changes. However, the distance along the track, which is estimated by integrating the vehicle velocity, contains errors because the wheel radius gradually changes over a long period. In this paper, a method to correct the running distance in high precision by utilizing the bogie twist corresponding to estimated twist irregularity of the track is proposed. The way to conduct temporal subtraction processing of the derailment coefficient is proposed, and the potential usefulness of the processing for track maintenance is discussed.