Railway pantograph contact strip monitoring through image processing techniques

During the train operation and especially at high speed, the pantograph-catenary contact is influenced by electromechanical wear phenomena. Consequently, the overall reliability of the railway system is reduced. In particular, the pantograph contact strips are subjected to severe abrasions during the running operations. Their maintenance and inspection are usually made manually with negative consequences in terms of costs and safety. Therefore, in the last years, no-contact monitoring and measurements techniques for the pantograph-catenary elements have been developed. A practicable methodology to measure the pantograph contact strip thickness is proposed in this paper. The employed approach is based on image processing techniques useful to detect geometrical variations of the pantograph contact strips. The no-contact measurement system is made through a cost-effective single camera. Several images of the pantograph equipped with unworn and worn contact strips are employed to verify the reliability of the proposed technique.