3D Printing electrical impedance tomography - first layer effects

BSc assignment

As additive manufacturing continues to evolve, ensuring consistent quality and reliability becomes increasingly important. Feedback serves as an essential tool for quality control and process optimization; for this, a robust monitoring method is required. One of the measuring methods that is being developed is Electrical Impedance Tomography (EMT). EMT works by measuring the impedance between the nozzle and bed of the printer through the 3D-printed object, which is printed with conductively doped polymers. When the impedance increases more than modelled, this means there occurs a defect in the print; this can be plotted for many points during the print giving a manufacturer an overview of all the defects in their print. One of the key points in the creation of a 3d print is the first layer. The first layers determine the adhesion, warping and general quality of the print to a great extent. Also, in this monitoring method, the first layer forms a critical connection between the print and the electrodes. this means that getting a good first layer is of great importance. Therefore the research of this bachelor assignment will be about the characterization of various first-layer effects, making it possible to distinguish between a good and a bad first layer. This will make the complete Monitoring method a lot more reliable. Resulting in more consistent print quality.

The main goal of this assignment is to be able to distinguish between a good first layer and a bad first layer using the EMT method. The second step in this is being able to distinguish between different error types, such that a suggestion could be provided to improve the first layer of the next print.

The first step will be doing literature research on what type of first-layer defects exist and how they are caused. Also, doing literature research on EMT to get more insight into the measuring method. The next step will be to do FEM simulations of the first layer to get more insight into the effects of bed-nozzle-distance, temperature and geometry on the impedance through the 3d print. These FEM simulations will also serve as a reference during the experimental phase. Next, with the knowledge gained, the test setup and method will be determined to measure all the different defects. With this setup, the measurements will be done by printing a first layer with changing parameters.

From the measurements, the data will be analyzed with the purpose of finding characteristics for each type of defect, making it possible to recognise such a defect when measuring the same type of characteristic.

After each step, the corresponding part of the report will be written. Finally, the findings will be presented in a presentation as well.