The Correction of the Nozzle-Bed-Distance in Robotic Fused Deposition Modeling

In this Paper, a method for online monitoring and correcting the Nozzle-Bed-Distance in robot-guided fused deposition modeling is presented. For development a six-axis industrial robot was equipped with a 3D printing nozzle and used for 3D printing. Additionally, two laser line sensors were mounted next to the printing nozzle at the robot’s flange for capturing process data.For online monitoring and correcting, the measurement data of those sensors are analyzed for the unique structure of the edge of the currently printed layer by multiple algorithms. By detecting this edge, the current Nozzle-Bed-Distance is calculated and compared with the planning data. Based on this comparison, corrections are derived and used for adjusting the robot’s trajectory. Furthermore, results of the application of the presented method to robot-guided fused deposition modeling are presented.Finally, the functionality of the method is reviewed and approaches pursued for its further development are shown.