Laser brazing is widely used for joining metal sheets in industrial applications, in particular in the automotive sector, where the requirements on surface quality are extremely high. Therefore, quality control and process observation cannot be omitted. This paper presents the current works of a camera based process control system. Hardware-based algorithms for estimation of machine parameters during the process are implemented on FPGA technology. In particular the process velocity is measured in real time which makes the system suitable for controlling tasks to react instantaneously on changes of the velocity.First experimental results on a controlled laser brazing process are presented. Additionally an evaluation of the accuracy of the hardware-based velocity measurement is given.

Laser material processes require constant energy input per unit length. Besides focal z-position, spot size, laser power and other process parameters, the relative travel speed (feed rate) of the laser spot on the work piece has the highest influence on the resulting energy input per unit length. In this paper a new metrology method is introduced, which enables users in industry and research to measure the real travel speed of the laser spot and the resulting contour of the trajectory.

Laser brazing has become firmly established as a joining process in the automotive industry. While this process offers many advantages, brazed seams also have to meet particularly high quality requirements. The challenge of creating a suitable online quality control system is magnified by the increasing use of aluminum in automotive engineering. This paper introduces recent works on the development of a system for controlling both aluminum and steel brazing processes. It also discusses some of the challenges connected to this task and discloses some of the results derived from the corresponding process analysis.