DARPA Proposes Ripping Up Dead Satellites To Make New Ones 186
Hugh Pickens writes "DARPA reports that more than $300 billion worth of satellites are in the geosynchronous orbit, many retired due to failure of one component even if 90% of the satellite works just as well as the day it was launched. DARPA's Phoenix program seeks to develop technologies to cooperatively harvest and re-use valuable components such as antennas or solar arrays from retired, nonworking satellites in GEO and demonstrate the ability to create new space systems at greatly reduced cost. However, satellites in GEO are not designed to be disassembled or repaired, so it's not a matter of simply removing some nuts and bolts, says David Barnhart. 'This requires new remote imaging and robotics technology and special tools to grip, cut, and modify complex systems.' For a person operating such robotics, the complexity is similar to trying to assemble via remote control multiple Legos at the same time while looking through a telescope."
Makes sense (Score:2)
This sounds like one of those brilliant ideas on paper, but one that will prove infinitely harder in reality. Re-use satelites, great idea, good luck doing it though.
Re:Makes sense (Score:4, Interesting)
I think it would come down to a cost-benefit sort of thing.
I'm just working my way through my coffee and I haven't had my breakfast yet, so excuse any insanity in the following.
The best way I could figure one could do this would be to have a robotic "scrap yard" in space - a space station of sorts with storage bays and robotic arms and/or drones that would pull in satellites and have them be disassembled through fly-by-wire. The parts would then be stored in bays and re-assembled.
I can see a few problems with this, of course. One way or another you're going to have to get the drones/station to the satellites. You're going to have to have *something* pull up next to the satellite and either drag it into a reclamation bay or have the whole reprocessing unit go up right next to it. Moreover you'd have to fuel the reclamation station somehow, meaning the satellite that scraps other satellites would eventually need to be scrapped or refueled itself.
It might be pretty difficult to actually re-build the stuff in space, too... so another option would be to just collect the junk and return it to earth. But I'd say it takes way more effort to get something back down from orbit than it does to get it back up there. You don't need to give satellites heat shielding because they're not really supposed to return. So if you were to go the "collect parts and bring them back down" route, you'd have to heat-shield everything, not to mention things like parachutes or retro-rockets that would permit to land without smashing into the ground at terminal velocity.
So... I don't know, this idea seems pretty nuts. I don't think we could do it until we have electrically-powered engines that can be recharged with solar power and a rather large, permanently-manned space station.
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Except that moving the birds from their widely differing orbits is a major expense.
Ion drive
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Except that moving the birds from their widely differing orbits is a major expense.
Not really. A lot of the valuable satellites will be in GEO or the geostationary graveyard orbits. Moving them around takes very little energy.
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Getting from one end of geostationary orbit to the other end and then slowing down to match geostationary orbit again is not trivial in terms of fuel costs.
Orbits have ends now?
Seriously though, the energy costs are trivial, and pretty much proportional to how fast you want to move around. Move into a slightly lower orbit (maybe a few m/sec delta-v for a Hohmann transfer), then wait for a while, then move back out. The shift around the orbit is dependant on how long you wait, not on how much fuel you expend. Drop down to an orbit around 1000km lower, and you can move around the whole of the GEO track in less than a month.
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Not a one dimensional problem (Score:2)
I'll try to put things more clearly. If you are going to change your path of movement to that of another object you not only have to get there but also match speed and direction with the other object. That means at least two changes.
Your "just drop down to a lower orbit" means a change in speed so an expenditure of fuel. Once you have the right position "below" as you suggest (which it won't be because it's not a stable orbit, in fact the altitude would still be around geostationary)
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You'd probably be going up at a reduced forward speed to act against gravity bringing you down over time.
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(which it won't be because it's not a stable orbit, in fact the altitude would still be around geostationary)
What are you smoking? Here, read this. [wikipedia.org]
it's then another burn to get to the object you want to match orbits with
Do you honestly think it takes the same amount of time to make an orbit regardless of altitude? I'll give you a hint: the ISS orbits the earth in 91 minutes.
That's not going to be a trivial expenditure of fuel unless the distances are trivial.
Distance? Who carers about distance? If you're moving, you'll get there.
gravity is making it harder to get back into geostationary orbit with every passing second.
What is this I don't even.
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You mean start thinking :)
That link is about something completely and utterly different because it's about shifting into different orbits and not another location in the same orbit - and it's a bit much that you both misunderstood that and implied that I'm on drugs because I didn't misunderstand that. Look at my other post for an idea of what velocity (both speed and direction) to start with.
Maybe this will help (Score:2)
(Ignore the underscores, spaces get formatted out and the junk filter hated my version with dots showing the arc.)
Once
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shifting into different orbits and not another location in the same orbit
That's how it's done. You move to a different orbit, wait a while and then move back. I thought you were on drugs because you keep talking about unstable orbits. The only way an orbit is unstable is if you intercept the body you're orbiting, reach escape velocity or a third body causes you to eventually do one of those things.
Here's how it works: you decelerate from GEO into an elliptical orbit with a perigee about 100km less than GEO. when you reach perigee, you decelerate again to reach a circular orbit
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The irony is your suggestion that is supposed to save fuel would cost
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Yes! I like the wheel analogy. OK: you don't get off the wheel, you move to a different wheel which is slightly smaller and slightly faster. Understand that?
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Note that the change in that example is not really an orbit because if you go all the way around you won't quite make it back to the high point on the next time around. Going lower costs because gravity increases the lower you go.
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No! Rotational speed is not the whole thing - 2D! (Score:2)
No you don't - with respect you are not even grasping the concept of rotation and are only thinking of fixed circles which is why I'm trying to describe it to you in a more familiar set of 2D co-ordinates. It's not a silly single dimension idea of concentric rings of wheels, there is a second dimension. You don't just step from one orbit to another without passing through intervening space and in fact you would never want to if you just want to shift to a different a
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What you appear to be describing is to thrust semiballaistically 'above' the orbi
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Except that moving the birds from their widely differing orbits is a major expense.
Not really. A lot of the valuable satellites will be in GEO or the geostationary graveyard orbits. Moving them around takes very little energy.
Don't forget the insurance recovery fees, 10%, I believe.
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Thrust is only critical when you're trying to get off a planet. If you're already in orbit, you don't care about thrust as much as Isp, which translates to your delta-v budget...
That said, this sounds like a pretty stupid idea. The expense of getting the robot miner/factory to the retired satellite is as much as putting a whole new satellite in place, one produced using the full resources of planet-bound manufacturing, not some ad-hock remote-controlled business, and I strongly suspect that each robot wo
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The most valuable resource a retired GEO satellite has is not the stuff in the satellite, but the position it occupies. The best solution is to build an attachable thruster as a secondary payload, and use it to nudge the satellite into interplanetary orbit so the new satellite can take it's place....
Exactly. Where are my mod points when I need them!!
The physical material in the satellite costs a few dollars. The rest of the cost is the cost of employment of large numbers of highly paid technicians on earth. As such any savings in trying to repair these things is elusive at best, and, given the nature of government programs probably impossible.
Better DARPA should invent cheap technology packages that can be launched by the hundreds latch onto or snag these dead birds and de-orbit them freeing their sl
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The physical materials are cheap, but the fuel required to orbit them is not. There is some value in the "real estate" as you say, but if you just move the existing satellites out of the way to make room for new ones launched from Earth, you still have to pay to get all that mass into orbit. If you can reuse some of that mass, then you can save a lot of fuel.
The whole satellite is greater than the sum of its parts. Yet, when a $150 circuit board screws up a 200 million dollar satellite network the cost of recovery and repair is less expensive due to re-usability factors.
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Why would they be in a hurry?
If it goes a little faster, it will move to a slightly higher orbit, and rotate more slowly. Wait for the place you're aiming for to catch up. Slow down, to move as fast as it does. You'll probably need tethers to do the final orbital adjustment, but by then your speed difference should be in the inches/minute range. (The tether is because it's quite difficult to exactly align in position and velocity in all three dimensions. But you want to get really close before you touc
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The Readers Digest of all things told me about that as a kid.
I wouldn't be too worried, the sheer kinetic energy of those things falling out of the sky is more dangerous than their radioactive properties. Once they've crashed the radioactive materials are so active that they are trivial to find (eg. fragments from a Kosmos impact in Canada were found from the air) but small enough that accidental exposure is likely to be minor. Those reactors are not the big steam
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Would people really panic so much anyway? (Score:2)
Take a look at wikipedia or elsewhere for these devices.
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You are describing having two satellites traveling at different velocity impact each other without utterly destroying either fragile device. Just because two satellites are in the same location at the same time does not mean one can realistically "grab" the other.
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For a person operating such robotics, the complexity is similar to trying to assemble via remote control multiple Lego at the same time while looking through a telescope
Sounds like brain surgery to me, not quite rocket science then. Shouldn't be too hard.
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Well, If I had to decide between flying with a rocket built by a self-taught rocket scientist and having my brain operated on by a self-taught brain surgeon, I think I'd take the rocket flight.
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I think the lego analogy is oversimplified. They should have said it would be like building your own telvision via remote control while looking through a telescope. Legos "just fit". Diodes, resistors, etc, don't just snap together - and neither will all those parts form satellites launched by different companies, for different purposes, over the span of a few decades. Almost nothing is going to "just fit".
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That was in line with my thoughts. If the devices were designed to snap out the fuel cells and reprogram the onboard logic, it could probably be made to work, at least for satellites of a similar type, but going much further than that would require technology which we don't yet have.
There's also the issue of these satellites being owned by somebody, even though they are still in orbit and unusable at the moment.
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Presumably a lot of military hardware uses a couple common satellite buses, so the parts could perhaps be interchangeable. I think that reusing across dissimilar craft is a pipe dream for now.
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Ownership can be easily resolved.
Start charging 'rent' for satellite positions in orbit. You can bet companies will start begging people to take their broken hardware.
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For a person operating such robotics, the complexity is similar to trying to assemble via remote control multiple Lego at the same time while looking through a telescope
Sounds like brain surgery to me, not quite rocket science then. Shouldn't be too hard.
The round-trip signal delay might also prove a problem for someone operating a remote gripper or performing some delicate real-time operation. You're going to need some serious AI on-board to handle most things, I think: the human operator would just issue directives and the local intelligence would get the job done. Eventually, as the software develops, you won't need the human.
This isn't exactly a trivial proposition: they'd probably have to spend a good chunk of that $300 billion getting this to work.
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I was just thinking it sounds like a really great game. It would make a dandy mod for some FPS engine that can handle rotating the player.
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I don't know... as soon as I heard about this, my immediate thoughts jumped to, "WE COME IN PEACE... PRIORITY OVERRIDE. NEW BEHAVIOR DICTATED. MUST BREAK TARGET INTO COMPONENT MATERIALS." ;)
annoying... "filter error: Don't use so many caps. It's like yelling".
Makes no sense (Score:3)
V'Ger (Score:2)
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It's a good idea to make mandates for the GEO orbit, but it's going to add weight and cost to the next round of birds. That makes them even more expensive, and you'd better be able to demonstrate that you will in fact be able to take advantage of it, or that will be added cost to no benefit.
It sounds like they're faced with the same situation software developers often are: reuse would be great, but much of the time it really is cheaper just to re-build another custom solution. And even if we do explicitly
Re:Makes sense (Score:5, Insightful)
This sounds like one of those brilliant ideas on paper, but one that will prove infinitely harder in reality.
Remember that "R" in DARPA's name? It doesn't have to work. It just has to be something interesting from which one could learn something new. And I could see a whole lot of useful/interesting stuff coming out of even trying to do something like this.
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Parent is exactly right. In the defense-sciencey world, there is a whole class of problems often called DARPA-hard. I think the term is one DARPA itself uses. My company recently missed out on an opportunity to bid a project for DARPA because we had an approach based on current technology which could be fielded very quickly. DARPA doesn't do that. DARPA does crazy, hard projects with the goal of advancing technology. This is definitely an area ripe for DARPA - it is a high risk, high payoff applicatio
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This sounds like one of those brilliant ideas on paper, but one that will prove infinitely harder in reality. Re-use satelites, great idea, good luck doing it though.
I have a closet full of old PC components and will never use most of them -- and those were designed to be interchangeable commodity parts. What are the chances that you can take a solar panel off an old satellite and use it for something? Did they standardize on micro-USB connectors? nope. Common voltage? nope. Standard mounting bracket? nope.
What other heavy items might be useful? batteries, telescopes, radios. Still less likely than my old PC parts.
The only chance this has is taking new parts up an
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I don't think a robot would be able to pull out a cell phone.
True, but what would happen is that the human operator would receive a message on his screen saying, "operation halted, programmed torque limit exceeded." The operator could then decided to override the limit and see if he can't work it loose. If that doesn't work, then he or she can call up the Car Talk guys.
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This sounds like one of those brilliant ideas on paper, but one that will prove infinitely harder in reality. Re-use satelites, great idea, good luck doing it though.
Odd thing is, my decades long study of the debris in orbit focuses one aspect on this very issue. Am I an engineer? No. Have I published any papers on this subject? No. Are my ideas valid? As valid as anybody elses.
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One question (Score:4, Interesting)
Would the whole process and those dated components even warrant all those expenses?
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Well, let's see. On the one side, we have DARPA's well-funded program, presumably chock full of experts in the field, who seem to think it is.
But then a guy on Slashdot isn't sure.
What to think, what to think...
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If nothing else, all the crap up there could be useful as reaction mass :)
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I agree we need to collect the space junk we've scattered in orbit. It's a hazard to future flights.
But I can't imagine that the hardware left up there is worth the expense of salvage. Most of the expense of a satellite is not the hardware itself, but the R&D that goes into them, the testing, the prototypes, the huge staff involved in the overall process of design and construction. The hardware itself is as disposable and unimportant as your PC.
Not components, but the travel... (Score:5, Insightful)
one of the primary drivers of the high cost is the launch costs,
It's interesting todo because the antennas and solar panels makes up quite a lot of the launch costs... they're not talking about reusing everything, just the heavy parts :)
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Heavy parts being optics, benches, batteries, flywheels, gyroscopes.... basically everything that is not reusable.
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Guess it is time to standaradize (Score:3)
if they can prove reassembly in orbit is viable then it suggests that the space industry needs to standardize to facilitate this.
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Or make the Chinese do it seeing as that stunt they pulled with that anti-satellite weapon contributed so substantially to the problem in the first place.The only other cases where the US in 1985 and again in 2008. Neither event contributed significantly to the problem and the latter debris is almost certainly already out of orbit.
Orbital Junkyards (Score:2)
Earthbound junkyards work, because there's lots of interchangeable parts that can be harvested from old cars. Can the same be said of satellites, or are they made of one-time built to order parts? Also, it's one thing for a junkyard part in your car to crap out on the road. Do you want to trust satellites in orbit with used parts? Oh, just stop by the orbital junkyard, for a new used part . . .
Re:Orbital Junkyards (Score:5, Interesting)
Some satellites are one-offs, but things like the GPS and NOAA constellations have dozens of virtually identical models. And speaking from experience, the space industry is moving (although ever so slowly) toward interchangeable parts to reduce costs. If they knew there were five or ten usable solar arrays for the taking, they could design the interface to accept them as well as a new parts.
The other interesting thing is that being able to salvage satellite parts would mean they would be less of a sunk cost and more of an investment. If they have a resale value after they are retired, that adds profit motive to the launching company.
Re:Orbital Junkyards (Score:4, Interesting)
Beat me to it...
There's a tendency now to try to use more common components in new satellites, especially for meteorology birds, while there's always new science, adapting existing hardware to do the work means you might get a couple of instruments on different spaceframes, and not cost as much as the gee-whiz one-offs. Someone already mentioned that R&D, testing, SRM&QA and launch services cost a bunch. If we COULD accomplish this, then restoring capabilities on-orbit would be great.
NASA had a "Flight Telerobotic Servicer" project in the early 90's. Don't know where it went but it did get a fair bit of support and a lot of good engineering talent was pointed at it. From my interactions with DARPA projects in the past, there's a fair chance that something useful will come out of this, even if the whole program is over-ambitious.
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NASA had a "Flight Telerobotic Servicer" project in the early 90's. Don't know where it went...
Not very far. After some study contracts, a $233 million dollar contract was awarded, but not much resulted. A prototype arm [roperresources.com] was built and is for sale for $42,000. Early planning proposed a test flight in 1991 [archive.org], with a rather easy set of tests. ("Peg in hole". With a human remote operator. Really. )
Ownership (Score:3)
Who does an old defunct satellite belong to? I suspect that it still belongs to whoever put it up there, or their executors, whoever bought the company etc.
And who is authorised to say that something is defunct anyway? Imagine such phrases as "We left it dormant for future needs." and "We were keeping it until we could go up ourselves, collect it, bring it back and repair it."
Scientists and engineers may have worked out the economics of doing this, but have they included that nasty concept of Corporate Lawyers?
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I'd expect that a satellite in a retirement orbit would still belong to the original owner, but the Corporate Lawyers aren't necessarily a large bar. If it's the original owner doing or benefiting from the salvaging, or if they get a sufficient cut of the savings, the lawyers can stick to writing contracts rather than getting in the way.
A larger problem seems to be that f
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If the original owners own the satellite, then would they be liable for the space junk they leave behind? Company A's space junk takes out Company B's working satellite. Let the corporate lawyer death-match commence! If there was real punching, then I would buy a ticket.
Lego, Lego Lego !!! (Score:2, Informative)
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there is no such thing as Logo's
Oh yes there is [wikipedia.org].
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It depends (Score:2)
A lot of reactions talk about the cost of fuel... seemingly these people forget that the satellite in question might still have fuel available that is going unused. What if out of this research it becomes clear that any new satellite needs the requirement to have enough fuel left for one last journey to the collector satellite orbit where it will be dismantled.
I wonder how a slashdot story about Darpa seeking input on a research project for some kind of network that can route around damage would be received
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that the satellite in question might still have fuel available that is going unused.
Considering the trivial amount of delta-v required to keep a satellite in GEO, that amount of fuel is likely to be tiny per satellite - ie not worth the fuel cost of boosting specialized fuel extraction/recycling equipment up to GEO and into specific orbits. Add this to the fact that fuel is usually pressurized, and that different satellites are probably using different fuel types - it's not the easiest component to deal with.
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Junkyards in Space (Score:2)
This sort of thing could really put a space station and its inhabitants to easy to understand use, fix and repair stuff in orbit. Keep most of the kinetic energy, get unobstructed sunshine, and catch some space junk - campy. Running a solar sailing race on the side as a hobby could be entertaining.
I remember that there existed a TV show about junkyard people in the past. Maybe one could come up with a space comedy around it. Some cross between Alien and Space Cowboys maybe.
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What we really need are some Jawas. [wikia.com]
I remember! (Score:2)
I made some comment about the topic in the past. Nice, DARPA listened, or to be more modest, had a similar idea.
Darn sad I can't find it now. Thinking about it, it really isn't that hard to come up with the idea, somebody like Oberth or Ziolkovsky probably already thought about it.
Why not a Service Station (Score:3)
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Remember when you were a kid... (Score:2)
Now - under the expert leadership that contaminating politics with money yields - the space program of the United States of America is going to wear patched satellites in outer space...that's progress.
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the space program of the United States of America is going to manufacture satellites in outer space
Now that's progress.
Orbiting (Score:2)
".. the complexity is similar to trying to assemble via remote control multiple orbiting Legos at the same time while looking through a telescope."
Fixed that for you.
What I would like to see (Score:2)
Why not fix the existing ones? (Score:2)
If one component is failed, why not replace it? The reason we don't do that now is that it's a complicated operation to do in space but if the point is to develop the technologies to make this kind of salvage possible, wouldn't it be just as easy to replace the broken part in some cases?
Reducing fuel needs (Score:2)
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Good thing the Chinese are currently developing something based on that novel idea.
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X-37 (Score:2)
We sorta have one in the X-37. No idea if it is big enough to haul a satellite, or if it even has a robotic arm capable of catching one.
I believe they are looking for new missions for this spacecraft to justify continue development. Perhaps the reason for the suggestion? They are currently proposing a "C" model that is 20% larger to provide the capability to haul astronauts in the cargo bay.
http://en.wikipedia.org/wiki/Boeing_X-37 [wikipedia.org]
And doesn't cost $1.5bn per flight (Score:2)
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I'd say only by the people that thought the entire idea of having an orbiting research platform was a bad idea in the first place. The thing's barely been built and people want to get rid of it before it's had a chance to be used for more than a handful of projects.
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Actually, a reusable space plane would be...
considerably more expensive than simply launching a new satellite, completely defeating the purpose.
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We need some kind of agreement for space like the one we have about Antarctica.
The Outer Space Treaty [wikipedia.org] is almost exactly that.
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