Wayside system for wheel–rail contact forces measurements

Abstract

The system for assessment of the wheel–rail contact forces can be used for multiple purposes, among them for estimation of the train running safety, for train axle load measuring or wheel flats detection, as well as for the other research analyses. As the wheel–rail rolling contact moves along the track during train motion, it is very difficult to establish a reliable and accurate system for measuring of contact forces. Measurement principle of the wayside system, presented in this paper, is based on rail strains measurements using strain gauges, connected into the Wheatstone bridges in a smart way, in order to achieve signal proportional to applied load. This principle uses independent component analysis (ICA) model in combination with system calibration for successful separation of vertical and lateral contact forces from recorded strain signals. In addition, the system provides identification of the contact point position on the rail during train passing over it, which further expands the possibilities of its application to wheel–rail wear analysis, contact geometry optimization etc.