A novel on-train measurement system for early detection of squats and other track defects

January 1, 2014 in

Conference Paper

Zili Li

Maria Molodova, Alfredo Núñez, Rolf Dollevoet


The 10th World Congress on Railway Research
Year: 2013
Location: Sydney, Australia

axle box acceleration, detection, squats

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In this paper, the use of longitudinal axle box acceleration (ABA) to enhance the signal-to-noise ratio is analysed. Compared to the vertical ABA, it does not contain vibrations of the rail, fastening, sleepers and ballast, so that the impact related vibration is much stronger in the signal. Extensive field test validated the effectiveness of the novel research for early detection of squats and other track defects. A combination of both longitudinal and vertical ABA, together with advanced signal processing, enhanced the ABA signal for detection purposes and provided a useful tool for infrastructure managers to evaluate preventive actions.