Tracking and height control in plasma robotic welding using digital CCD camera. Issue 1 (October 2016)

• Record Type: Journal Article
• Authors: Wang, Weixi; Yamane, Satoshi; Suzuki, Hikaru; Toma, Jiro; Hosoya, Kazumichi; Nakajima, Toru; Yamamoto, Hikaru
• Is Part Of: International journal of advanced manufacturing technology. Volume 87:Issue 1/4(2016)
• Page Start: 531
• Page End: 542
• Publication Date: 2016-10
• Subjects: Plasma robotic welding -- Profile control -- Height control -- Image processing -- MATLAB/Simulink; Manufacturing processes -- Periodicals; Production engineering -- Periodicals; 670.427
• DOI: 10.1007/s00170-016-8437-3
• Languages: English
• ISSNs: 0268-3768

Abstract

Abstract An image processing method that automatically tracks the weld line during plasma robotic welding has been developed, with self-regulated standoff of the torch. The hiding of the plasma electrode in the torch poses a positional problem to human engineers. Therefore, this method replaces human sight with a visible automatic control that teaches the exact position of the plasma torch. The image processing method for automatic tracking is optimized by a hybrid process that involves an improved threshold method and height control. The threshold method exploits multiple thresholds to raise the precision of boundary detection and improve the welding quality. The height control method effectively maintains a constant standoff of the plasma torch. The correct standoff, which maintains the keyhole while ensuring stable and optimal welding, was determined in numerous basic experiments. The proposed method largely improves the efficiency of welding work and effectively reduces the negative consequences of false torch guidance.