While laser cutting and laser welding are typically separate processes, researchers at the Fraunhofer Institute for Laser Technology (ILT; ilt.fraunhofer.de) have developed a “combi” head that permits both cutting and welding; capacitance sensors not only perform distance control but component measurement.
In all, the combi-head addresses various processing issues ranging from equipment foot-print on the factory floor to clamping, storage and transport. Said Dr. Dirk Petring, group manager, ILT Macro Joining and Cutting, “The connection of combi-proces-sing and capacitive component measurement is not only suitable for concealed T-joints in structural components of automobile con-struction, but can also offer new solutions wherever curved or deep-drawn sheet metal parts need to be joined together to create a precise sheet metal group in spite of their geometric tolerances.”
The system uses what they’re calling a “Tool Center Point” (TCP) that’s common to both the cutting and welding processes. Through the use of processing optics, which they describe as being analogous to a single-lens reflex camera, they’re able to determine overall operating conditions. Said Dipl. Ing. Christoph Franz, ILT scientist, “The system measures directly in the area of the processing position and not at the head or in the robot axes. Since the process gauges the ongoing measurement accuracy, no measurement errors are made.”