Extraction of Weld Seam in 3D Point Clouds for Real Time Welding Using 5 DOF Robotic Arm

Abstract

Welding involves the union of two workpiece halves along a common edge of interface, also called as the weld seam. In this paper a novel algorithm has been proposed which is independent of the shape of the workpiece to classify and extract weld seams from 3D point clouds. The real time tracking of the weld seam is also demonstrated on a 5 axis robotic manipulator. The aim was to eliminate the need for manual computation of the robot trajectory and also ensure that the overall pipeline is computationally efficient. The two workpiece halves have been clustered into different point clouds and the edge of interface on either of the halves has been specified using the centroid shift method. The precision recall metrics of our algorithm were very close to the ideal values on any shape of the weld seam. Singularity avoidance, trajectory planning, kinematics of the robotic manipulator is beyond the scope of this paper.