A Novel Method on Wheelsets Geometric Parameters on Line Based on Image Processing

The flange thickness and rim inside thickness of the wheelset are key parameters that influence the wheel-rail contact. With the speed continuous increase of the rail vehicles, the wear of wheelset is becoming more and more serious, thus accelerating the changes of wheelset´s flanges, which will certainly bring security hidden troubles to the operation of railway, so it is very important to realize dynamic measurements of the wheelset´s flange thickness and rim inside thickness. This paper proposes a novel real-time measurement method to wheelsets based on the image processing. This system based on the triangular principle uses CCD (Charge-coupled device) to obtain the information of the wheelsets. In this system, the flange thickness can be uncontacted measured in real time. The standard deviation of the rim inside thickness is 0.47mm and that of the flange thickness is 0.635mm, and the error range is ±0.8mm, and ±1.0mm, respectively. When the train passes through the measurement system at the speed of 5km/h, the measurement results show that the measurement system can meet the measuring requirement on line.