Research on Track Fitting of Big Frame Intersection Line Seams

Abstract

When big frame intersection line welded structural assemblies are produced and assembled, certain errors always come to being, so generally speaking, both instructional and fitting methods are applied to the seam track in the welding robot, in which welding quality is largely decided by the precision of the track fitting. A detailed analysis about the acquisition and fitting of saddle-back welding seam is given in this article, in which the authors put up ellipse fitting method based on the general rules of intersection line deformation, and three-coordinate separated least square algorithm fitting based on curve fitting. In the guidance of some instructing points in key position, simulations are made to verify the two methods separately. The result shows that the three-coordinate separated least square algorithm method is more precise than the other one. Therefore, it is fit for big intersection line welding frames.