ABSTRACT
ABSTRACT: Monitoring the conditions of railway tracks is essential for ensuring the railway safety. In-service vehicles equipped with sensors and GPS systems can act as probes to detect and analyse real-time vehicle vibration. Recently, a compact on-board sensing device has been developed. This paper describes the track condition monitoring system that uses a compact onboard sensing device and diagnosis software. The diagnosis software provides the function of detecting track faults using root mean square (RMS) of the car-body’s acceleration. It also allows analysis in the time-frequency domain using wavelet transform. A Kalman filter was applied to solve the inverse problem to estimate track irregularity from car-body acceleration. This estimation technique is utilized to estimate the track irregularity in longitudinal level (track geometry and 10 m-chord versine). The estimation technique can support a change of the vehicle velocity by selecting impulse response in the measurement equation for the vehicle velocity. Estimation results revealed that the proposed estimation technique is effective for track condition monitoring with acceptable accuracy for conventional railways.
