Getting large structures, such as solar or antenna arrays, into space is a tricky proposition, as they need to be able to fold up or contract to fit into a delivery vehicle, and then expand or be deployed in orbit. This constraint has traditionally limited the size and design of these structures, but a new type of fabrication technology may change all of that.
Instead of sending a finished structure (or parts of one) into space, sending the raw materials into orbit and then constructing it there with robotic "spiders" and 3D printing technologies may be the future of large spacecraft and their components.
Tethers Unlimited's SpiderFab technologies is said to allow for automated construction of large space structures, which would begin with a compact "embryonic" form sent up from Earth, and then the other components would be fabricated and integrated into the structure by robotic assembly systems. The company was just awarded a $500,000 contract from NASA to continue with the development of their technologies, which could radically change how large spacecraft are designed and built:
"On-orbit fabrication allows the material for these critical components to be launched in a very compact and durable form, such as spools of fiber or blocks of polymer, so they can fit into a smaller, less expensive launch vehicle. Once on orbit, the SpiderFab robotic fabrication systems will process the material to create extremely large structures that are optimized for the space environment. This radically different approach to building space systems will enable us to create antennas and arrays that are tens to hundreds of times larger than are possible now, providing higher power, higher bandwidth, higher resolution, and higher sensitivity for a wide range of space." - Dr. Rob Hoyt, TUI’s CEO and Chief Scientist
Tethers Unlimited is also working with NASA to develop what they call a "Trusselator" apparatus that can fabricate large truss structures in space, in order to construct large solar arrays and antennas while in orbit.
"The Trusselator is the key first step in implementing the SpiderFab architecture. Once we’ve demonstrated that it works, we will be well on our way towards creating football field sized antennas and telescopes to help search for Earth like exoplanets and evidence of extraterrestrial life." - Dr. Hoyt