Robust weld line detection with cross structured light and Hidden Markov Model

In this paper, we propose a vision-based weld line detection system with cross structured light (CSL) and Hidden Markov Model (HMM). Our consideration is that the laser stripes projected by CSL can reflect the convex shapes of weld lines, capture horizontal and vertical weld lines simultaneously and are insensitive to illumination changes. The Hidden Markov Model filters out various noises on the weldment surface and then detects laser stripes precisely, which guarantees the accuracy of weld line location. Experiments on practical and simulated datasets show that the results of our approach have great improvement to classical Hough transform based method.