Image Feature Analysis of Weld Pool in Aluminium Alloy Twin Arc PMIG Welding Based on Snake Model

Continuous weld pool images of 6 mm aluminum alloy from rear and side directions in twin arc welding were successfully obtained with a near-infrared filter and a neutral density filter at an exposure time shorter than pulse period. A modified Snake active contour model for weld pool contour extraction was proposed and the contours of the two directional weld pool images were extracted accurately. Through analyzing the two directional continuous weld pool images it was found that the average geometric feature of continuous multi frame images of weld pools other than one single image can reflect the actual welding process.