3D printing for large space structures has gotten considerable press recently, following a press conference by startup company Deep Space Industries. Unnoticed by the press is Tethers Unlimited, a small company in Bothell, Washington that’s already working on a 3D printer for large space structures.
Tethers Unlimited has received a $100,000 grant from the NASA Institute of Advanced Concepts to begin development of the technology, which the company calls Spiderfab.
Spiderfab combines the techniques of fused deposition modeling (FDM) with methods derived from automated composite layup to enable rapid construction of very large, lightweight, high-strength, lattice-like structures with both compressive and tensile elements. SpiderFab would enable structures to be launched in extremely compact form as raw feedstock, which would be used to create structures optimized for the microgravity environment rather than the launch environment. The technology could also evolve to use orbital debris and extraterrestrial materials as feedstock.
Spiderfab could create structures with higher-order hierarchies, such as a truss-of-trusses, which can achieve 30-fold mass reductions compared to first-order structures. This approach could enable deployment of antenna reflectors, phased-array antennas, solar panels, and radiators 10-100 times larger than current state-of-the-art deployable structures.
Potential Spiderfab applications include multiple high-gain antennas in Earth and solar orbit to support a deep-space communications network, long-baseline interferometry systems for terrestrial planet-finder programs, and submillimeter astronomy of cosmic structure.
Spiderfab structures would re-configurable and repairable on orbit. The technology could also evolve to use orbital debris and extraterrestrial materials as feedstock.