“The conductive printing project is an ongoing research topic, aiming at the full integration of complex electronic circuits into 3D-printed objects.
3D-Electronics, an augmented version of the slicing tool Slic3r is under active development. The electronics extension allows to load a schematic definition, created with CadSoft EAGLE, into the toolpath generated by Slic3r. SMD-components and wires can be arranged and routed in an object and the result is exported as gcode, printable with most FDM-printers. All informations for automatic component placement with OctoPNP are integrated into the gcode. Electronics for Slic3r is published under a GPLv3 licence and available on Github: https://github.com/platsch/Slic3r/tree/electronics.
Details on the algorithms used for wire embedding are described in a paper [PDF]: 3D-Printable Electronics - Integration of SMD Placement and Wiring into the Slicing Process for FDM Fabrication, SFFS, Austin, 2016.
OctoPNP, the control software for interactive part handling is implemented as a plugin for the common 3D-printer host software OctoPrint. OctoPNP is published under a GPLv3 licence and available on Github: https://github.com/platsch/OctoPNP.
In the first iteration, a large FDM 3D-printer has been modified to produce conductive traces with a second extruder during the printing process. SMD-components are then placed into the uncured conductive ink by a camera-guided pick and place system to complete the circuit. To achieve this, the printer is extended by:
A Tray consisting of a grid of boxes to store SMD parts in a defined position
A head camera to locate the exact part position on the tray
A (second) bed camera to precisely align the parts during the placing operation
A vaccum nozzle to grip parts
A second extruder to process conductive silver filled polymer inks
The technical description of the printer hardware and concept can be found in a paper [PDF] that was published at the 26th Solid Freeform Fabrication Symposium 2015 in Austin.
The scad files for the hardware parts are available on Github as well: https://github.com/platsch/RepRapPNP. The repository Contains a branch for components to be mounted at a cnc-device as well as parts to extend the IndustrialRepRap printer platform.”