Image collection and processing system for welding pool and proximate seam using multiple image detectors

Yanming Quan, Qilin Bi

COMPUTER MODELLING&NEW TECHNOLOGIES 2014 18(12B) 234-241

School of Mechanical and Automotive Engineering, South China University of Technology, Guangzhou, Guangdong 510640China

Because of the dynamic nature of welding parameters and power characteristics, the arc ignites and extinguishes too rapidly. The length and luminous intensity of the arc is unstable. This makes the imaging of the welding pool and seam problematic for selecting and fixing time of exposure for the camera. Moreover, the luminous intensity of region being welded decreases sharply along the welding seam. The seam that is not in the proximity of the welding pool is too dim for imaging by the camera, making the length of the seam imaged too short. In this study, an image-capturing system based on multiple image detectors and image fusion are used to image the welding pool and proximate seam during MAG welding process. The offset between center point of the welding pool and centerline of seam and the seam width are determined by innovative measuring techniques that include collection of images of the pool and seam using multiple image detectors. The results obtained have shown that the accuracy of offset between welding pool and seam is ±0.5mm, and the accuracy of seam width is ±0.5mm. This imaging and measuring method developed in this study is promising for tracking and monitoring of high-speed welding, especially the MAG welding where interference from the arc is a problem.