Tacked Weld Point Recognition from Geometrical Features

In order to guarantee that a workpiece is securely fixed during a welding process, some areas of the workpiece should be tack welded before the formal welding process starts. Weld seam images captured at these tacked weld points, however, will be different from normal weld seam images. These differences present a difficulty when trying to obtain accurate feature points from an image. Tacked weld point recognition is the key factor of the robustness and stability in the tracking process of welding. It is easy to distinguish tacked weld points on regular fillet weld seam images, rather than irregular fillet and overlapped weld seam images. This paper analyzes the geometrical features of tacked weld points and introduces the methods to recognize these tacked weld points. Experimental results show that the methods proposed by this paper are robust and the weld point recognition is accurate.