Nondestructive testing of train wheels using differential-type integrated Hall sensor matrixes embedded in train rails

A nondestructive testing method for inspecting cracks in train wheels is proposed in this study. The train wheels can be inspected without disassembly, as soon as the train enters its shed, using this method. The proposed method uses differential-type integrated Hall sensor matrixes (D-IHaSMs) embedded in the rails. This D-IHaSM can inspect cracks over a large area at high speed with a high spatial resolution. In addition, a custom signal processing circuit is designed to match the requirements of the D-IHaSM. The artificial cracks formed in the train wheels are inspected and the crack volume is estimated using the D-IHaSM system.