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Robust High-Speed Melt Pool Measurements for Laser Welding with Sputter Detection Capability

  • Nicolaj C. Stache
  • Henrik Zimmer
  • Jens Gedicke
  • Alexander Olowinsky
  • Til Aach
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4713)

Abstract

Although lasers are widely used for welding in precision engineering industry, it is still a challenge to achieve high accuracy in creating and positioning welding spots at extremely high processing speed.

Towards this end, we propose a system for monitoring the welding process in order to ensure good quality of the welding spots. Our technology enables high speed image acquisition confocally to the laser beam with a direct view onto the melt. This innovative system permits accurate estimation of the melt pool’s position and radius, which, however, must be performed at frame rates above 200 fps. We therefore employ fast correlation based approaches for sampling the melt pool’s contour and robustly fitting a circle to it. In addition, the approaches enable sputter detection via outlier classification.

To assess the performance of each presented method, extensive experiments are conducted. The proposed paradigms can furthermore be conveniently adapted to a variety of problems dealing with rapid shape estimation in noisy environments.

Keywords

Welding Process Laser Welding Welding Spot Step Edge Direct View 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2007

Authors and Affiliations

  • Nicolaj C. Stache
    • 1
  • Henrik Zimmer
    • 1
  • Jens Gedicke
    • 2
  • Alexander Olowinsky
    • 2
  • Til Aach
    • 1
  1. 1.Institute of Imaging & Computer Vision, RWTH Aachen University, 52056 AachenGermany
  2. 2.Fraunhofer Institute for Laser Technology, Steinbachstr. 15, 52074 AachenGermany

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