No abstract

Remote laser beam welding significantly outperforms conventional joining techniques in terms of flexibility and productivity. This process benefits in particular from a highly focused laser radiation and thus from a well-defined heat input. The small spot sizes of high brilliance laser beam sources, however, require a highly dynamic and precise positioning of the beam. Also, the laser intensities typically applied in this context result in high process dynamics and in demand for a method to ensure a sufficient weld quality. A novel sensor concept for remote laser processing based on optical coherence tomography (OCT) was used for both quality assurance and edge tracking. The OCT sensor was integrated into a 3D scanner head equipped with an additional internal scanner to deflect the measuring beam independently of the processing beam. With this system, the surface topography of the process zone as well as the surrounding area can be recorded. Fundamental investigations on aluminum, copper, and galvanized steel were carried out. Initially, the influence of the material, the angle of incidence, the welding position within the scanning field, and the temperature on the OCT measuring signal were evaluated. Based on this, measuring strategies for edge tracking were developed and validated. It was shown that orthogonal measuring lines in the advance of the process zone can reliably track the edge of a fillet weld. By recording the topography in the trailing area of the process zone, it was possible to assess the weld seam quality. Comparing the results to microscopic measurements, it was shown that the system is capable of clearly identifying characteristic features of the weld seam. Also, it was possible to observe an influence of the welding process on the surface properties in the heat-affected zone, based on the quality of the measuring signal.

Kurzfassung In diesem Beitrag wird eine Möglichkeit zur realitätsnahen Simulation von Montageanlagen durch den Einsatz der Hardware-in-the-Loop-Technologie (HIL) beschrieben. Die vorgeschlagene Simulationsumgebung verknüpft reale Steuerungshardware mit echtzeitfähiger Simulation und Visualisierung von Montagesystemen. Durch eine derartige Simulation, bestehend aus dem mechanischen Aufbau, der Steuerungshardware und der Software, kann das Anlagenverhalten frühzeitiger als mit realen Prototypen bestimmt und abgesichert werden. Der Artikel beschreibt außerdem mögliche Szenarien und Anwendungsfelder zur Nutzung der Hardware-in-the-Loop-Simulation im Bereich der virtuellen Inbetriebnahme von Anlagen.