A study on the welding seam tracking by using Laser Vision Sensor

Abstract

This paper suggests one of the pre-measurement methods to trace a welding path. The welding path is measured by the LVS (Laser Vision Sensor). A line laser is projected on the weldment and a vision sensor captures images. Center points of the welding path are detected through image processing. Measured image coordinates are transformed to robot coordinates by coordinate transformations. The experimental structure is composed by 1-axis robot, cylinder, LVS. The rolling cylinder that is carved V-groove generates the continuous welding path and the 1-Axis robot follows the V-groove. The tracking algorithm is applied to generate the welding path that is obtained by the correlation of a set of groove center points. It is important that the robot traces the welding path accurately in the margin of error. Thus, the process of error data distinction and modification is implemented through the estimation algorithm.