At MONTEM we always strive to have ongoing research projects on interesting and cutting-edge fields within tech. In particular, we focus very much on developing new tools that can improve or simplify the product design process. One such project (and let me clarify that this is still very much work-in-progress), is the integration of electronic components directly within 3D-printed objects, making it possible to use a regular 3D printer to print electrically conductive traces and simply plug in components while printing; the end result is a fully working 3D-printed object with sensors, microprocessing capabilities etc., without any soldering or printed circuit boards.
Recent advancement in 3D printing material technology has opened up the possibility of printing fully working electronic circuits with regular FDM 3D printers.
The project started out as part of my own master's thesis together with product designer Morten Tore Lauridsen. Now, we continue to develop and improve upon the technology at MONTEM, and in this post I will present the main progress we've made so far.
To achieve the overall vision in the simplest way possible, we have worked with widely available FDM 3D printers with dual-extrusion capabilities. In our case, we made our own custom-built Prusa i3 printer, but most existing FDM printers with dual-extrusion will work. The reason for the necessity of multi-material printing is that the printer needs to work with both an isolating as well as a conductive material simultaneously; the isolating material will create the overall structural integrity of the object, while the conductive one will connect the individual electronic components with one another. Based on extensive testing, we found that the best PLA-based conductive material to work with as of 2016 is the conductive graphene filament from BlackMagic3D, since it has a relatively low resistance compared with filaments from other companies.
One issue with conventional dual-extrusion 3D printers where both extruders move on the same carriage, is that the two extruders can contaminate each other's work - so ooze from the conductive extruder, for example, can destroy the work of the isolating one, or even worse - cause a short-circuit. So while conventional dual-extrusion printers can certainly work for this purpose with a bit of tweaking, we improved upon the printing technology by making so-called parking extruders. In essence, this means that instead of the two extruders moving on the same carriage, they now move individually along the same axis. While one extruder is printing, the other one simply slides back to the side and parks, having the extruder capped while waiting for its turn. This results in much less ooze and cleaner prints, lowering the risk of short-circuits that would otherwise be prominent.
With this setup we are able to print simple objects containing electronic components such as Arduinos, LEDs, buttons, speakers, wireless transmitters etc., using our open-source Rhino3D library of standard sockets that fit commonly available components. These components can be connected in 3D space, further widening the possibilities compared with PCBs. While we can relatively easily print working objects that contain an array of simple input/output devices, development is still needed in terms of improving upon the stability of the printing process, as well as making it possible to use more advanced electronics, such as small-scale SMT components, which will require a radically different printing technology.
At MONTEM, we believe that the potential of this field is widespread - potentially making product design so much more available and easy to approach. We will continue to write about this project as we make further improvements to our implementation. Please see the resource section at the bottom to find the open-source socket library as well as further documentation, so you can experiment with the possibilities yourself (chapter 6 of the thesis document is the most relevant for makers).