Adaptive control of varying joint gap in LBW - VarGa

Important results from the project

The aim of the project has been to develop a non-intrusive sensor system solution for laser welding of butt joints both to find and track the joint when the gap is close to zero (almost invisible) and to secure a uniform weld geometry, independent of varying width of the joint gap. The system shall be possible to integrate in a laser beam tool. A vision-based in-process system has been developed that controls the beam to the joint (integrated and demonstrated by Permanova Lasersystem) and that also can control the wire feeding to compensate for varying joint gaps.

Expected long term effects

The developed system for laser welding gives the possibility to substantially reduce the time for setting-up, fixturing, check of robot path and quality control. The demands on joint tolerance can be reduced by the developed system with adaptive control of the laser beam position versus the joint and adaptive control of the wire feeding to compensate for varying gap width. Adaption to new applications (material, thicknesses etc) will be facilitated and production will be more flexible. The cooperation between research organizations, industry and system integrator is strengthened.

Approach and implementation

The project group consisted of participants from medium and large companies (GKN Aerospace, Siemens Industrial Turbomachinery, Brogren Industries, Wugang Tailored Blanks and Northcone), laser system integrator (Permanova Lasersystem), branch organization (Svetskommissionen) and from the academy (Högskolan Väst, Luleå Tekniska Universitet and Swerim). Industrial need and benefits have by this been met. The latest results within the research area have been used as well as the possibility to commercialize the system has been demonstrated.