The military spends a lot of money on building communication satellites and sending them into space. Lots of them are still up there, long after they've failed or become obsolete.
Wouldn't it be neat to recapture and recycle the components, which are often still working, while also getting rid of all that space junk? The Defense Advanced Research Projects Agency (DARPA) thinks so, and it wants to use robots for the job.
The Phoenix program's goal is the development of technologies that can harvest the components of retired, nonworking geostationary earth orbit (GEO) communication satellites. Reusing those components, such as space apertures, solar arrays, and antennas, would slash the costs of building new ones. It might also speed their replacement, in the military's effort to maintain 24/7 global communication capability for soldiers on the ground.
In the proposed Phoenix program, robotic arms and end effectors can decouple an antenna from its retired military communication satellite and reuse it in a new satellite, saving money, maintaining global coverage, and cleaning up space junk. (Source: DARPA)
Very small satellites, or "satlets," would ride along during commercial satellite launches in a payload orbital delivery system (PODS). Separately, an on-orbit tender, or satellite servicing satellite, will be launched into GEO. When the tender arrives on orbit, the PODS will detach itself from the commercial satellite host and connect with the tender.
The tender will be equipped with robotic grasping arms that will remove a satlet and attach it to, for example, the antenna of a nonfunctioning or decommissioned satellite that it has harvested from the graveyard orbit. The result is a new satellite created in GEO that's ready to be deployed. The robotic arms could also replace parts on, and perform other service tasks for, satellites that are still functional. (Watch the video below showing an artist's depiction of the proposed tender salvaging a retired satellite's still usable antenna.)
Several different technologies are needed for the Phoenix program, and many are still in development. As part of the project's first phase, DARPA has selected Honeybee Robotics Spacecraft Mechanisms to develop two different types of new telerobotic end effector prototypes for satellite rendezvous and docking. End effectors function as the hands of a robot arm, or manipulator. The prototypes will be designed to enable a servicing satellite to dock with and manipulate communications satellites in GEO.
Other robotics-related technologies being developed for the program include industrial robotics and tool changeout mechanisms, as well as remotely operated surgical robotics tools and imaging systems.
Is it complete science fiction that in movies they wear magnetic boots or would it be reasonable to use electromagnets to make sure items don't bounce away from each other? Would it make sense to save parts in an orbit higher or lower than geosynchronous and count on the different angular velocities account for most of the positioning?
You're right about that motif, Ann. I remember one of the first space movies I saw as a kid in the 1950s. An astronaut was outside the spaceship doing some maintenance and bumped into something outside the ship and it sent him flying, tearing his tether and sending him out into space spinning with no oxygen. Probably pretty accurate.
The video, of course, is a simulation, so things may look a lot easier than in reality. OTOH, it's amazing how we've been doing accurate synchronization in 4D for decades, including when human lives are at stake.
I agree about the speed, Chuck. It all looks like it's in slow motion. And maybe in some sense it is. But it must be a technological wonder to match speeds and connect like that. Just a slight speed difference and you have crash.
You'd think that if you can track with any degree of precision where all this LEO junk is, you could use an intelligent satellite to catch up these items and give them a "tap", enough to destabilize them and cause re-entry. I know there's an initiative to require all satellites to be equipped with some de-orbit mechanism so that when they reach end of life they don't become just another piece of flotsam out there. I wonder how long it would take for this stuff to re-enter on it's own. Safe to assume that with all the stuff that's up there now, not anytime soon.
I do find that now with all the sats floating around dead and possible interference with GPS units and C3 sats that DARPA is looking at the junk. 25+ years ago some of us were looking at automated ways to do just this but found more roadblocks than a prison break. Even if we had eveything on the launch pad, NASA and the Govenrment were not going to let a private group launch. Things have changed some and hopefully enough that we can get the junk cleaned up.
I remember the program. It came out about 5 years after the design work had begun. My parents thought we were working on the show instead of the real thing.
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