On-line process monitoring in laser materials processing – Techniques for the industrial environment

Substantial reasons for the increasing utilisation of the laser beam in numerous areas of the industrial production are on the one hand the increased efficiency in comparison with competing techniques, on the other hand the features of the laser beam as a tool itself. To gain a profit, a highly automated quality control of the production process is needed. The laser welding process offers several modern and novel possibilities for process monitoring systems or process control but the complexity of the laser process itself, that means the dependence of the processing result on several process parameters, does not facilitate their use.There are some state-of-the-art systems for monitoring laser processes but even for these systems based on various measuring approaches, in some applications the implementation in a real industrial environment is not beneficial, sometimes annoying.This paper will describe the work in a current German government founded project, which is called INESS. The goal of the project is mainly combining information coming out of different regions surrounding the laser beam to achieve an unambiguous process status and to achieve a modular integration of the different measuring techniques into one processing head. The realisation of this system is based on the fusion of several measuring principles in mainly one, camera based sensor.