Camera-based Measurement of Rail Sleeper Vibrations

This paper presents a camera-based sensor system for contactless measurement of lateral vibrations in rail sleepers during Dynamic Track Stabilization (DTS). DTS enhances rail track stability by inducing horizontal vibrations that compact and reorganize ballast stones, thereby correcting defects and increasing resistance to lateral movement of rails. The proposed system employs a high-speed camera mounted on a moving rail vehicle, capable of measuring sleeper motion at sub-mm resolution at moving speeds up to 5 km/h. By analyzing image sequences, the system accurately measures vibration frequencies within the relevant 25–45 Hz range. Laboratory validation using a laser distance sensor, along with successful field testing, confirmed the sensor’s ability to reliably measure vibration frequencies and amplitudes. This technology enables detailed assessment of track stabilization processes, offering valuable insights for track condition monitoring and predictive maintenance.