Vision-based real-time welding line detection algorithms for automatic welding robot

Abstract

In heavy manufacturing industries, such as construction, shipbuilding, and automobile, the welding technology plays an important role in determining the quality of manufactured products. Especially in the case of the shipbuilding, steel welding accounts for a considerable portion of the overall workload. In order to improve productivity, research on automation of welding processes has been recognized as one of the important fields in industries and academia. Recently, a simple automation of the welding robot perpendicularly following the welding surface using a displacement sensor has been developed, but it still has a considerable disadvantage that it must be monitored by the user to follow the exact weld line. In addition, existing technologies to detect the weld line using computer vision have been limited to estimating the weld line in real time because the quality of the image is deteriorated due to the arc generated in the welding. To address the limitation, this study suggests an arc-insensitive optical system and a real-time processing algorithm using spectrum analysis and computer vision algorithms.