Method for Controlling Welding Apparatus, Controller, and Welding System

A controller for welding apparatus, comprising:

• an acquisition component, configured to perform an acquisition step to acquire an image of a groove of a weld seam, so as to obtain a groove image;
• a first determination component, configured to perform a first determination step to extract a laser line according to the groove image, wherein the laser line is a line formed by projecting linear structured light on the weld seam;
• a processing component, configured to perform a processing step to at least fit the laser line to obtain a first function;
• a second determination component, configured to perform a second determination step to determine a third function according to the first function and a second function, wherein the second function is a distance measurement function between the theoretical position of a welding gun and a predicted position of the welding gun, the third function is a loss function between the predicted position of the welding gun and the theoretical position of the welding gun, and the theoretical position of the welding gun is a theoretical position of the welding gun for welding a current weld pass of the groove;
• a third determination component, configured to perform a third determination step to determine the predicted position of the welding gun when the third function converges to be a gun alignment position of the welding gun, and perform welding according to the gun alignment position of the welding gun;
• and
• an execution component, configured to repeatedly execute the first determination step, the processing step, the second determination step and the third determination step, until the welding of all weld passes of the weld seam is completed.