Fraunhofer Institute for Production Technology IPTResearch project "Robotex"
With the process of laser surface structuring, complex 3D geometries can be repeatedly marked or engraved. Compared to conventional surface structuring techniques, this process offers economic, ecological and design advantages. For this purpose, a focused, pulsed laser beam is guided over the surface with high precision and speed using a laser scanner. However, the beam guidance system will only provide a limited range of motion for the laser beam. Work pieces that exceed this range have to be machined sequentially. For this purpose, a subdivision of the work piece surface is required, dividing it into suitably sized segments. The handling device, e.g. a 5-axis-machine, subsequently positions the beam guidance system at each segment. After processing such a partial surface, the process is repeated until the component is completely machined. Due to high demands on the positioning accuracy, high-precision and thus expensive system technology is required.
Within the RoboTex project, a cost-effective industrial robot for large-area laser structuring is being used for the first time. The system related inaccuracies of the robot are compensated by intelligent methods. Markings are placed on the entire component at defined intervals. Using an integrated camera, the markings are recognized and subsequently evaluated. Based on the deviation of the detected marking position in the camera image from the expected position, a displacement and rotation of the scanning field can be calculated. This information is used to adaptively generate the processing data for the laser and execute it afterwards.
By eliminating additional cost- and maintenance-intensive technology to increase the robot accuracy, a very robust and cost-efficient large-space laser system is developed. The investment costs for such a system are expected to be approximately 20% of the cost of a conventional system.
Project partners
- Zertrox GmbH & Co. KG
- Eschmann Textures International GmbH
- ModuleWorks GmbH