Optical Remote Dimensional Inspection of Live Contact Wire in Train's Electro-Supply Network

Abstract

An optical structured illumination of 3D object as a light band method for automatic noncontact wear measurement and defects detection of a contact wire network is presented. The experimental device can extract main technological wire parameters like remaining height with RMS value down to 0.15 mm. Also the cross-sectional area of the wire can be measured with RMS area noise value of 1.5 mm 2 , which is sufficient for a confident decision-making related to the automatic wire wears and defects on railways, tram and trolleybus lines, and similar systems of vehicles electro-supply.

Measurement Method for Contact Wire Wear Based on Stereovision

“…The average difference value and the maximum difference value are 0.08 mm and 0.13 mm, respectively, which demonstrate that the method has good measurement accuracy. The measurement accuracy of contact wire wear in this study is basically consistent with that reported in the literature [8,9].…”

“…For the vision measurement method, the wear surface of contact wire is illuminated, and the wear width is extracted by analyzing the image taken by the cameras. Several vision measurement methods were reported, such as structured light vision measurement [8][9][10] and stereovision measurement [11][12][13]. For example, researchers from RTRI developed a contact wire wear measurement system based on structured light vision measurement [8].…”

“…The RTRI's system was installed on a Shinkansen vehicle and was capable of an accuracy of within ±0.1 mm in residual thickness. Chugui et al [9] developed a structured light vision measurement system with an RMS error of the residual thickness of 0.15 mm and a measurement rate of ~150 Hz. Nie [10] adopted a 2D laser sensor (ELAG Elektronik AG, Winterthur, Switzerland) to measure the wire wear of metro rigid catenary.…”