A vision-based approach for rolling contact fatigue evaluation on a wheel material

A vision-based experimental methodology was developed for monitoring the surface state evolution of specimens during bi-disc rolling contact tests, aimed at providing information for identifying the damage phenomena. The system is based on a high-speed camera and three laser pointers for illuminating the specimen surface. Images of the specimen surface are acquired and processed, allowing the definition of synthetic surface state indexes, as well as the 3D reconstruction of the damaged surface topology. The vision system was applied to alternated dry-wet rollingsliding contact tests on railway wheel steel specimens, highlighting its effectiveness in the damage evaluation.