THEORETICAL AND EXPERIMENTAL

STUDY ON SEAM CENTER DETECTION

BASED ON WELDING VISUAL IMAGE

CENTROID ARITHMETIC

GAO Xiangdong  CHEN Zhanglan  CHEN Yongping

(Faculty of Mechanical and Electrical Engineering, Guangdong University of Technology, Guangzhou 510006 )

Abstract: A novel method of seam center detection based on the welding visual image centroid is presented. Based on the weld pool image centroid arithmetic and CCD work principle, a centroid model whose characteristic corresponds with the centroid value, workpieces temperature field and the seam center position is established. The model numerical solution under a certain welding condition can be acquired after the welding temperature field is numerically simulated. The analysis result of model influence factors indicates that the factors such as welding current, traveling velocity and seam width influence the model apparently. Experiment formula is obtained according to the tendency analysis of model solution. Also, the least-square method is employed to build the specimen spatial data according to various welding parameters. Then the particular parameters of model are obtained according to multi-linear regressive analysis. Therefore, the centroid-offset formula with actual welding parameters is acquired. It is shown by actual welding experiments that the welding position can be detected by using the image centroid arithmetic.

Key words: Image centroid Seam center Detection Model

CLC No: TG316.7

国家自然科学基金(60375012)和广东省自然科学基金(020176, 6021444)资助项目. Received 20060422, received in revised form 20061225