The PODS would be ejected on command from the GEO satellite and collected by the servicer, which would store the satlets and tools on its tool belt before heading to graveyard orbit to rendezvous with the donor spacecraft. There the servicer would attach the satlets to the antenna, which would then be severed from its satellite and towed to GEO, where it would take up position as a reconstituted communications satellite. The robot “mechanic” would then stay on orbit, and be sent additional tools and satlets to amortize its cost over several repurposing or servicing operations.
The Phoenix demonstration will test key aspects of the concept, but not a complete operational system. “In the first demonstration we will attempt to bring up the functions to repurpose an antenna,” Barnhart says. “For the demo, we will take the satlets up with us [on the servicer/tender launch.”
The demonstration aims to repurpose a small 1-5-meter antenna and validate that radio-frequency communications can be restored via the rebuilt aperture in graveyard orbit. “For the demo, we will not bring the aperture to GEO,” he says. Darpa has yet to select a donor satellite. “There are 1,300 space objects [in] GEO, of which about 500 are retired and 500 active satellites,” says Barnhart. “Of the 500 retired spacecraft, 140 have been identified with apertures that would be useful for the demonstration. We are continuing to work through a number of identified candidate assets.”