Multi-Material Freeform Fabrication of Active Systems

Current Solid Freeform Fabrication (SFF) technologies can manufacture, directly from digital data, end-use mechanical parts in an increasingly wide variety of engineering materials. However, commercial SFF systems remain costly, complex, proprietary, and are limited to working with one or two proprietary materials during the course of building a part, hindering their broader application and the impact of the technology. The work we present here demonstrates (1) that SFF systems can employ many materials and multiple processes during the course of building a single object, (2) that such systems can produce complete, active, electromechanical devices, rather than only mechanical parts, and (3) that such multi-material SFF systems can be made accessible to, and are of interest to the general public. We have developed a research-oriented, multi-material SFF system and employed it to produce not only mechanical parts, but complete and functional Zn-air batteries, electrical wiring, flexible circuit boards, strain-gages, electromagnets, electroactive polymer actuators, organic-polymer transistors, and electromechanical relays. We have also developed and published the Fab@Home Model 1 open-source, multi-material, freeform fabrication system design. The Fab@Home project has received broad public and media attention, and more than 100 Model 1 machines have been built by individuals around the world.