Feature point extraction based on contour detection and corner detection for weld seam

Abstract

In an arc welding robot system with vision sensor, the extraction precision of the weld seam position has an important effect on welding quality. However, due to disturbances such as camera resolution, scanning posture, reflections, etc., it is a great challenge to identify weld seam accurately. In this paper, weld seam is considered as a special curve which consists of feature points, based on that, an effective method is proposed to extract the feature points by using contour detection and corner detection. Experiment results show that feature points can be extracted successfully by using this method, so that the robot can weld the work part along the feature points detected. The limitation of this method is that the detected feature points are sometimes inconsistent with the weld center points, which may affect the welding quality.