Adaptive control of arc welding using infrared sensing

Infrared thermography was employed to identify changes in plate thickness during the arc welding of steel plates. The step changes in plate thickness were found to uniquely affect the surface temperature distributions of the plates during the welding process. A technique was developed to identify the thermal profile irregularities ahead of the weld that were indicative of changes in plate thickness. The results of this investigation suggest that the calculation of the area under the linescan can be successfully used to identify thickness variations in a plate as it is being welded. The gradient of the area beneath the linescan was further found to be indicative of changes in plate thickness.