Research on calibration technology in rail abrasion detection based on machine vision

When using machine vision system to detect rail abrasion, we need to calibrate camera and light plane in order to obtain geometrical relationship between camera and light plane along with coordinates of points on rail profile in world coordinate system. This paper uses camera calibration based on 2D planar calibration target to realize camera calibration. The experiment indicates that it has many advantages such as high accuracy, simple procedures, et al. Using indirect calibration method to conduct light plane calibration, this approach uses target curve with single-pixel width to get the pixel coordinate of feature points so as to reduce the effect on accuracy caused by the width of light.