On-line control of robotized Gas Metal Arc Welding

On-line control of welding and soldering is a strategic issue for the complete automation of robotized plants. The proposed control system aims to detect the most critical defects in industrial applications. It is based on the analysis of images coming from two cameras installed on the welding torch: the arc and the pool observation allow monitoring the welding process; a laser stripe is used for the weld bead inspection. The image analysis algorithms developed are based on the extraction of features, which have been selected after a long series of experiments. In addition to pre-processing, different filters have been implemented to increase the system reliability, for the high noise in images. A basic control system is also addressed. The system has been tested in weld overlay cladding.