Development of Welding ProfileMeasuring System withVisionSensor

Thispaperdescribes thedevelopment ofthe3D measurement systemforwelding robot. Thesystemconsists ofPC basedvision cameraandstripe-type laserdiode. The total system isassembled intoacompact modulewhichcanbe attached totheheadofwelding robotsystem. Especially, this systemisdesigned tooperate atdifferent working distances. Forthis purpose, themechanism whichadjusts thefocal length andtherelative location betweencameraandlaserdiodeis devised. Thesetwoconfigurations arechanging according to current working distance automatically. Mostpartsofimage processing suchascameracalibration, correction ofdistortion, andline extraction areimplemented andrunning onPC.After measuring thewelding profile, thethreedimensional shapeof theworkpiece isobtained andsomeuseful features forrobot manipulation arecalculated. Someexperiments arecarried out andsomeapplications aregiven.