Condition monitoring of shinkansen tracks using commercial trains

Three inertial measurement algorithms were developed to measure the longitudinal level of tracks using a track condition monitoring device mounted on commercial Shinkansen trains. Two algorithms employ digital processing and are called "Frequency variable difference filter" and "Speed variable moving summation". The other algorithm employs analogue processing using a frequency variable low-pass filter. Test results confirmed that all methods are able to calculate a 10 m versine longitudinal level with high precision without any waveform distortion. An experimental prototype of a digital inertial device applying the "Frequency variable difference filter" with small hardware load was made, and a test was conducted to confirm its performance. As a result, the output of the prototype achieved good correlation with data from the existing track geometry car.