Automation of Post-Processing in Additive Manufacturing with Industrial Robots

Abstract

The use of industrial robots for the production of small scale manufacturing or even single pieces is rarely economical. The high investment of time and money required to teach a collision-free trajectory under consideration of all boundary conditions prevents the usage of robots until now. That is why it is still common practice in the industry for individual post-processing steps to be carried out manually, although they could be automated with today's technical possibilities. In this paper, we present an approach on how to use existing production data (STL and G-code) to generate trajectories to automate post-processing steps. These paths can then be executed by an industrial robot, for example to post-process an additive manufactured object and remove its support structures. The object may not be damaged during the process, so all movements of the robot and its tool are checked for collisions with certain parts of the object and the environment. While material is being removed, the corresponding data structure is updated accordingly to always provide a realistic representation of the current state. This approach was evaluated by removing support structures from multiple and different-shaped objects successfully. Furthermore, we used the same approach to mill pockets in material just by changing the input data.