Perception of an Opto-Mechanical Torch for Linear Welding Robot Using Monocular Camera

Abstract

The welding process expose the welder to harmful material such as smoke, sparks, radiation and high temperatures generated by the welding pool. Robotizing this process changes the welder role by the welding operator. However, the online correction of the welding parameters needs to be automatically done by the robot. In this work, we propose a method to keep constant the distance between the welding arc to the groove in a multiple pass welding using a controlled opto-mechanical device. This distance may vary due to welding deposited in the previous welding pass and deformations in the welding plates. Our method measures the distance through a machine vision, trajectory planning and height control of the welding torch using a low cost embedded system. The obtained results using a monocular system and a simple point laser allow us to convert image domain primitives into pixels for real domain in metric scale.