Rapid Assemblers
Imagine a fundamentally new desktop fabrication process capable of making perfectly repeatable multi-material 3D objects with microscale precision - where the physical material itself is digital!
Traditional analog (continuous) materials have error associated with every dimension (left). Digital (discrete) materials are a fundamentally different concept in which a 3D object is defined by the presence or absence of a 3D pixel at each location within a lattice.
In the digital domain, a 3D object is composed of repeating, fundamental building blocks known as voxels. A digital (discrete) object is described perfectly by the presence or absence of a voxel at each location within the lattice, in contrast to traditional analog materials where each dimension has an inherent error. All current manufacturing processes (even digitally controlled CNC machines) are fundamentally analog. Over the past several decades, the transition from analog to digital has revolutionized many fields, most notably computing and communication. Many of the advantages gained here translate to digital matter, such as perfect repeatability with no noise and better precision than the assembly machine. However, a finite resolution must be chosen, and processing time increases.
This concept video illustrates the basic idea of a physical voxel printer capable of combining otherwise incompatible materials in a 3D printed object.
The modular sphere deposition modules can deposit spheres on demand up to about 10Hz.
VoxJet
Just like inkjet printers scan continuously and deposit drops of ink into paper, the VoxJet is a rapid assembler that deposits physical voxels (or 3D pixels) to create 3D digital matter. This research platform is capable of depositing a 3D lattice of small spheres at a continuous deposition rate of ten spheres per second. Up to three materials may be combined in any configuration. An integrated binder deposition system and non-contact laser feedback system enable robust, repeatable results.
The voxjet has been used to demonstrate fully recyclable multi-material 3D printing. In this process, voxels of multiple materials are printed and bound together by a reversible binder. When it's no longer wanted, the bonds holding the spheres together are reversed (in this case using water-soluble glue), and the individual spheres are reclaimed and fed back into the machine.
VoxLayer
Voxlayer addresses some scaling concerns of VoxJet by placing an entire layer (O(n) build time vs. O(n²)) at once.
Further reading:
Hiller, J., Lipson, H. (2009) "Fully Recyclable Multi-Material Printing" Solid Freeform Fabrication Symposium (SFF'09), Aug 3-5 2009, Austin, TX, USA.
Hiller J., Lipson H., (2007) “Methods of Parallel Voxel Manipulation for 3D Digital Printing”, Proceedings of the 18th Solid Freeform Fabrication Symposium, Austin TX, Aug 2007, pp. 200-211.