Pentagon's In-Orbit Satellite Recycling Program Moving Forward

An anonymous reader writes with an update on DARPA's plans to rebuild satellites in orbit. "A year old DARPA program which aims to recycle satellites in orbit has started its next phase by looking for a guinea pig defunct satellite to use for evaluating the technology required. The program involves a Dr Frankensat 'complete with mechanical arms and other "unique tools"' and blank "satlets" to build upon.' Need parts! Kill the little one!" If we're ever going to build space craft and other things in orbit, this seems like a great first step.

Comments

Re:Pentagon work

[bughunter]

You're quite unfamiliar with how DARPA works, aren't you?

Wait. That's not a question. You obviously are.

If it works...

[Oxford_Comma_Lover]

If it works, great. If it doesn't, one collision can set us back *decades* in terms of the Kessler effect (i.e. space junk that makes it harder to launch/maintain orbit without more collisions).

Re:If it works...

[dasunt]

If it works, great. If it doesn't, one collision can set us back *decades* in terms of the Kessler effect (i.e. space junk that makes it harder to launch/maintain orbit without more collisions).

If one collision is anywhere near likely to trigger the Kessler effect, wouldn't it have most likely happened by now?

After all, several nations have blown up satellites in orbit. That is far more likely to have caused the Kessler effect than a collision between two satellites resulting in an unknown, uncontrolled orbit. We already have satellites up there that are uncontrolled.

Re:If it works...

[DanielRavenNest]

I have a solution for that. Combine scoop mining of the Earth's atmosphere and mining the debris belt for raw materials/working parts/satellite refuel and repair station:

* http://en.wikibooks.org/wiki/Space_Transport_and_Engineering_Methods/Resource_Extraction#Scoop_Mining

* http://en.wikibooks.org/wiki/Space_Transport_and_Engineering_Methods/Orbital_Mining2

The first gives you a relatively cheap source of fuel for your electric thruster to putter around orbit, the second makes use of that fuel to do something useful. Depending on the state of the dead satellite or debris you can either:

- Lower it's orbit enough to re-enter quickly if you can't make any other use of it
- Feed it into a processing unit as raw materials
- Salvage it for working parts
- Repair broken parts to return satellite to operation
- Refuel satellites that are otherwise functional and just ran out of fuel.

It's basically the same service a tow truck and garage provides on Earth, except in space. If we never picked up road debris on Earth, it would be a mess too. What we were lacking is an efficient way to pick up space debris, and the combination of mining air from low orbit + electric thrusters is around a 100 times improvement in propulsion efficiency.

Re:If it works...

[mk1004]

It's basically the same service a tow truck and garage provides on Earth, except in space.

Except when we don't, it ends up in somebody's front yard, on blocks.

Re:If it works...

[Oxford_Comma_Lover]

The issue is that when two satellites collide, they tend to create more junk--it's not just unplanned orbits, it's stuff breaking apart and going in lots of different directions.

"Several Nations" pretty much means China, at least in recent history. But their test of their anti-satellite weapon actually did set us back decades.

Basically, a lot of stuff falls to earth slowly, so lower orbits empty of old junk over time. When stuff collides and shatters into lots of pieces, all going every which way, it undoes a huge amount of the clearer orbits we gain from stuff falling.

DARPA Hard

[bughunter]

DARPA doesn't do anything little, or incremental, or obvious. In the jargon it's gotta be "DARPA Hard."

The obvious, incremental technology would be to build satellites so that they could be refueled on orbit by something like this Pheonix spacecraft.

But no! That's too easy. It's gotta be a McGuyver. Anything else is aiming too low.

Something useful will come of this program, it typically does. And, as usual, it may not be what they expected nor will it necessarily be immediately practical.

However, that's exactly what DARPA is paying for.

Re:DARPA Hard

[tokul]

The obvious, incremental technology would be to build satellites so that they could be refueled on orbit

Launching craft into orbit costs a lot more than maintaining it in orbit or building new more advanced satellite. Your satellite refueling is ecofriendly, but burning old sats in atmosphere is more cost effective solution.

Oh crap

[Anonymous Coward]

Isn't this the same agency that funded the corpse-eating robot? It all makes sense now. It will kill and eat astronauts and cosmonauts for power. Then it will make copies of itself from various satellites. Finally, it's clone army will come to Earth and devour us all.

Re:Oh crap

[swv3752]

Skynet has to come into being somehow.

Roger Wilco

[Russ1642]

Maybe this will spur enough public interest to bring back the Space Quest series.

Re:Roger Wilco

[Anonymous Coward]

FYI:
SpaceVenture, a KickStarter project by the creators of Space Quest (successfully funded but still accepting PayPal donations)

Re:Roger Wilco

[crazyjj]

Sounds more like Salvage 1.

Another (small) step

[k(wi)r(kipedia)]

If we're ever going to build space craft and other things in orbit, this seems like a great first step.

It's another small step, but definitely not the first step. Unless you don't consider the ISS as space craft and a fairly big thing in orbit.

Re:Another (small) step

[camperdave]

Unless you don't consider the ISS as space craft and a fairly big thing in orbit.

Fairly big thing in orbit: Yes. Spacecraft: No.

The ISS is a space station... says so right in the name.

Re:Another (small) step

[bluefoxlucid]

It's ridiculous is what it is. Tons of fuel and energy to course correct in 3D and do computer calculations without a fixed anchor point. Gravity is excellent for making sure things hold together the way you want; weightlessness is excellent for making things move in a slow, controlled manner. Too bad weight and mass are two different things.

We can't absolute match speeds, stuff drifts and pushing against something causes lots of shifting with nothing to reset the momentum. Leveraging against gravity is a fantastic tool: you don't have to worry about nudging something and then pulling it back to stop it in place (along with anything it touches/pushes against). In space, you'll need to push as hard to move something in any direction as you would to push it sideways on earth; you'll have to push a lot harder (in fact, as hard to move it in any direction) to move it "down"; and you gain the advantage of not having to push so hard to move things "up". Seems like a minimal gain for all the hassle and energy expenditure needed to manage shit flying all over the place.

Assembly in minor gravity--such as on the moon--makes more sense.

Re:Another (small) step

[k(wi)r(kipedia)]

Assembly in minor gravity--such as on the moon--makes more sense.

It probably won't waste that much more fuel to get from LEO to the moon, the one place with any significant gravity consistently nearest the Earth. But the equation changes greatly when you have to land stuff then hurl it back into space (the reason perhaps why the Russians are bold enough to offer cow jumps over the moon but not visits to the Apollo landing site). A cost-effective moon-based manufacturing requires the development of a mining industry or in situ resource utilization. Magnets and robotic arms can solve much of the floating all over the place problem.

Re:Another (small) step

[CrimsonAvenger]

Fairly big thing in orbit: Yes. Spacecraft: No.

The ISS is a space station... says so right in the name.

So, what's the functional difference between the two, now?

Re:Another (small) step

[dpilot]

Most spacecraft can do something significant to change their orbits. While the ISS does have a thruster system, it's just for maintaining the existing orbit and making minor changes to avoid junk.

If you really want to blur the line, try a Cycler.

Re:Another (small) step

[nitehawk214]

Fairly big thing in orbit: Yes. Spacecraft: No.

The ISS is a space station... says so right in the name.

So, what's the functional difference between the two, now?

Strapping on a nice big engine

Such as the one that is a part of the Zvezda module?

Unlike space stations in science fiction, ISS is actually flying at 7km/s.

Re:Another (small) step

[camperdave]

If we're ever going to build space craft and other things in orbit, this seems like a great first step.

It's another small step, but definitely not the first step. Unless you don't consider the ISS as space craft and a fairly big thing in orbit.

Exactly! We all know that it was Neil Armstrong who took the first step.

how to be a billionnaire in this department

[fluffythedestroyer]

1. make a company 2. find investors & show your plans 3. launch craft to space around earth 4. clean everyone's crap and make them pay 5. profit 6. huge profit 7. fuck load of profit (optional) 8. buy Nasa 9. change how they work since it's needs lots of changes (look at history and you'll know what mistakes they've done) 10. profit again

Re:how to be a billionnaire in this department

[fluffythedestroyer]

crap... the format...damn it

Re:how to be a billionnaire in this department

[ColdWetDog]

10. Fix Slashcode
11. Adulation and Adoration from geeks in basements everywhere!

Best idea from the Pentagon in a while

[Anonymous Coward]

It seems fairly obvious to me - Satellites become useless if just a few key parts fail, leaving the rest of the equipment in perfect working order.

If just one of the radio receiver, radio transmitter fails, the solar panel fails, the engine (gyroscope or whatever) fails, it is worthless, even if everything else still works.

The trick of course will be to standardize the parts to make it easier to mix and match.

Re:Best idea from the Pentagon in a while

[vlm]

It seems fairly obvious to me - Satellites become useless if just a few key parts fail, leaving the rest of the equipment in perfect working order.

The problem is if you gathered 200 old satellites you'd probably have 190 marginal to outright dead batteries, 200 mostly empty maneuvering/positioning fuel tanks, and 200 radiation damaged solar panel arrays.

You pretty much get to keep the perhaps decades obsolete electronics and the chassis, and those don't weigh much. So if you have to launch 80% of the mass of a new satellite to get a remanufactured old satellite, you're better off launching 100% of the mass for a completely new satellite that was integrated and checked out on the ground.

You can also imagine the agony if after rebuilding a week later the 25 year old battery charger fried wasting all the work.

There's a reason why old cars are scrapped instead of merely replacing the rusty chassis, worn engine, worn transmission, worn tires, worn suspension, rusted dinged body panels, worn carpet, ancient/obsolete cassette player radio... If the only thing you're keeping is the comfy drivers seat, just remove it and place it in a new car, if you must, because it makes no financial sense to replace "everything else" on the old car.

Re:Best idea from the Pentagon in a while

[tmosley]

Tell that to Cuba. They don't seem to have gotten the memo.

I suspect it would be easier to get new cars to Cuba than it is to launch a satellite. But what do I know?

Re:Best idea from the Pentagon in a while

[h4rr4r]

The far bigger trick will be matchin orbit grabbing the satellite and then moving onto the next one without spending more than the cost of satellites getting all that fuel up there.

Re:Best idea from the Pentagon in a while

[Muad'Dave]

Are you kidding??? Do you have any idea how abjectly destitute the average Cuban is, thanks to Castro? They may have great health care and education, but that's about it. I talk to Cubans regularly via amateur radio, and I'm constantly amazed at how well they manage to keep their radios going with nothing more than spit and bailing wire.

The only reason they drive 50's vintage cars is because that's all that were on the island at the time of Castro's takeover - no one can afford a new car, even if they were allowed to import one!

From wikipedia:
"Typical wages range from factory worker's 400 non-convertible Cuban pesos a month to doctor's 700. That is around 17-30 U.S. dollars a month."
"After Cuba lost subsidies in 1991, malnutrition resulted in an outbreak of diseases and general hunger."
"Pensions are among the smallest in the Western hemisphere at $9.50. In 2009, Raul Castro increased minimum pensions by 2 dollars, which he said was to recompense for those who have "dedicated a great part of their lives to working... and who remain firm in defense of socialism"."

Re:Best idea from the Pentagon in a while

[tmosley]

WHAT? You have literally no idea what you are talking about.

Some ridiculous number of cars on the road in Cuba have been on the road since before the embargo started. You think 33+% of all car owners on that island do that?

http://en.wikipedia.org/wiki/Yank_tank

Re:Best idea from the Pentagon in a while

[Patch86]

Do you have any idea how abjectly destitute the average Cuban is, thanks to Castro?

And definitely not to do with the US-led economic embargo, right?

Sarcasm aside, seriously- it's the embargo. Whether you're pro-Castro or pro-USA, everyone admits it's the embargo that's done the economic harm. The Cubans admit it because it's evidence that their problems are not of their own making, and the Americans admit it because it justifies their action (economic harm is exactly what the embargo was designed to do).

There's a reason they went further down the pan after the collapse of the Soviet Union- they lost their biggest non-embargoing trading partner.

Re:Best idea from the Pentagon in a while

[vlm]

I think you're missing that the embargo is pretty much a US only thing and only the elite can afford the car and the gasoline... the average cuban dude doesn't have a personal american made car from 1950.

The Russians had decades to flood the island with their cars, eighty zillion european and asian countries have normal relations with Cuba.

I stick by my argument, they are just showing off by driving old cars. Plus or minus some confiscatory tax avoidance (like maybe a 100% sales tax, or a 50% annual prop tax on a new import, who knows). If they really wanted to drive something new it would be trivial to drive a fiat or a toyota or "something with a russian name".

Re:Best idea from the Pentagon in a while

[triffid_98]

There's a reason why old cars are scrapped instead of merely replacing the rusty chassis, worn engine, worn transmission, worn tires, worn suspension, rusted dinged body panels, worn carpet, ancient/obsolete cassette player radio... I

Most people can't do their own work. Therefore cars reach a point where repairs cost more than the car is worth. If they could, then scrapping it makes far less financial sense than refurbishing the worn parts.

That said, this is kind of the same situation, at least until the ISS gets it's own Autozone/PepBoys module.

Re:Best idea from the Pentagon in a while

[Muad'Dave]

A little googling refutes your position:

Under current law, they [Cuban citizens] can only freely buy and sell cars that were on the road in Cuba before Fidel Castro's 1959 Revolution. Russian Ladas and modern Peugeots and Kias now outnumber the 1950s classics, but, for the most part, they are owned by the state and cannot be sold on the free market.

Re:Pentagon work

[crazyjj]

Oh, it's DARPA? Well in that case let me revise it:

It will never materialize at all.

Re:Pentagon work

[ganjadude]

yeah, like that crazy internet thing, no body uses it

First step in building things in orbit?

[NoNeeeed]

"If we're ever going to build space craft and other things in orbit, this seems like a great first step."

What, you mean like the ISS (over 100m long and 70m wide)?

I think we took the first steps in building things in orbit quite a long time ago.

I still think this is a very cool idea though, and the more practice we get at building stuff in space the better.

Re:First step in building things in orbit?

[Lumpy]

And spacelab before it. http://en.wikipedia.org/wiki/Spacelab

OR Mir? http://en.wikipedia.org/wiki/Mir

ISS is just the latest beta test. we really need to get serious and build a real space station.

Not going to work...

[bobbied]

Building reliable satellites is a long and expensive process, even in the best of situations here on earth. Re purposing an already built and flying one in space is surely going to be even worse, producing really expensive and unreliable satellites in the process.

This is like trying to do an overhaul of a fighter jet avionics while the thing is in flight. Yea, you could possibly do it, but why would you want too try?

Now if they want to start designing into satellites a way to make re-provisioning of satellites while in orbit possible, like adding ways to easily attach more fuel or replace payload modules, I'd find it worthwhile. Perhaps even standardizing a way to build satellites out of modular components that share a base interface so it is possible to just assemble them like tinker toys in space would be workable. But simply trying to rebuild something not designed to be worked on from the mounds of junk already in orbit is not going to have much success, is going to be very expensive, and is likely going to require manned spaceflight (something we don't do here in the USA right now) and the likelihood of success is pretty low.

Efforts like the refurbishment of Hubble aside, this effort seems doomed for failure, unless the components they are trying to use are designed for reuse and happen to be in the correct orbit.

Re:Not going to work...

[tmosley]

In flight? No, it's more like repairing a ship while at sea (because the satellite doesn't have to maneuver itself while it is being repaired). Ships are repaired at sea on a fairly regular basis, at least enough for them to limp back to port. If there were no ports available, it wouldn't be that much of a stretch to fully repair and resupply them with floating drydocks. It would help if there were humans there, of course.

Re:Not going to work...

[bobbied]

In flight? No, it's more like repairing a ship while at sea (because the satellite doesn't have to maneuver itself while it is being repaired). Ships are repaired at sea on a fairly regular basis, at least enough for them to limp back to port. If there were no ports available, it wouldn't be that much of a stretch to fully repair and resupply them with floating drydocks. It would help if there were humans there, of course.

So all this just begs the question, what kind of efficiency are they expecting to gain? Are we trying to lower launch costs by not having to lift heavy components into space? Well launching the equivalent of a dry dock is *not* going to be cheap.

Re:Not going to work...

[swv3752]

Sure it will if we go Nuclear. Project Orion or Nuclear Thermal (ie Nuclear Light Bub). The Lightbulb gives you both a rocket engine and a power station.

Maytag Repairman

[OldGunner]

Why not just launch the woefully underutilized Maytag Repairman (and his dog) into space?

Sure, it's to 'recycle' them

[argStyopa]

I'm sure that this has NOTHING to do with the X37, and any conceivable plan to disable/grab/dissect/plunder Chinese/Russian satellites in orbit.

No, no, we're going to send a multimillion-dollar mission aloft to repair and enable broken space junk that even if restored to functional within a year or three is grossly outdated by new advances in hardware.

Re:Sure, it's to 'recycle' them

[SuricouRaven]

Sounds plausible, actually. It's a handy repair tool, plus it can open up the enemy spy and communications sats and jack in directly to get at precious unencrypted data. Spy on the spies, intercept communications, maybe even discover their keys.

Re:Sure, it's to 'recycle' them

[Jeng]

It is rather hard to hide in space, you grab someones satellite and they will know who did it.

If it is to be done, it would only be done during war otherwise it would start one.

Re:Sure, it's to 'recycle' them

[h4rr4r]

So what magic material is this satellite made out of that will not just be cooked to death?

Shedding heat in a vacuum is a real problem.

Re:Sure, it's to 'recycle' them

[Jeng]

To be "stealthy" in space you need to be the same temperature as what is behind you, and that varies with where you are in your orbit.

Re:Sure, it's to 'recycle' them

[networkBoy]

Painting it black is pretty effective at shedding heat. Most radar absorptive coatings are black / dark already...

Re:Sure, it's to 'recycle' them

[h4rr4r]

Not in space it won't be. Why do you think even spy sats are so shiny?

Paint it black and the next time it hits the sun light it is dead.

Why not just de-orbit them?

[Lumpy]

small "microsats" with a single use booster. Release one that attaches to the target and then fires it's booster to deorbit the target. IF you used a solid fuel rocket you could make it very small and highly effective.

Re:Pentagon work

[SuricouRaven]

DARPA runs high-risk high-payoff research. Ninety-nine out of a hundred things they try fail - but the one that actually works is revolutionary.

Re:Pentagon work

[MyLongNickName]

DARPA sure gave an enormous boost to computer-driven cars. In my opinion, DARPA has done a lot to advance science... it is a shame that so much science seems to depend on military whims, however.

Re:Pentagon work

[crazyjj]

I hope you can do better than one success 40 years ago.

Re:Pentagon work

[Cryacin]

Then again, this project sounds like the scenes in all those hollywood movies where they throw a crapload of junk on a table and say, "We need to build a working relay station from only these parts!" Except in this case, it's using robots... in space!

Anyone got McGuyver's phone number? I'm sure he can get the robot to do *something* with the duct tape and swizzle stick.

Re:Pentagon work

[Cryacin]

98 to go then.

Re:Pentagon work

[crazyjj]

Companies have been working on computer-driven cars for as long as I can remember. I can remember experiments on this similar to what Google is doing now even back in the 70's and 80's. Hell, they were talking about the idea even back before DARPA existed (anyone ever seen those old "What life will be like the future" shorts from the 50's?). They even made a TV show about it.

Re:Can we *not* do this???

[crazyjj]

Considering I got modded into Troll oblivion above for saying it, I'm glad to know that there is at least one other sane person here.

If this is like ....

[PPH]

... Seattle's recycling program, were going to have to separate the navigation, communications and orbiting thermonuclear weapons platforms. And we will have to remove and fold the solar panels. Then we'll have to have them in the correctly marked bin, ready for pickup on Wednesdays.

Too much trouble. I'm just going to dump them on the nearest passing asteroid.

Re:Pentagon work

[Anonymous Coward]

Yeah, which is why I said "boost" not "they invented it". They made a lot of people aware of it through their high profile challenges and have dumped a lot of money into making it a reality. The prize money freed up a lot of university funding and the Stanford team in particular benefited. Your Knight Rider argument is so silly as to not being worth rebutting.

--MylongNickName

Strange idea

[vlm]

Dr Frankensat

I have a strange idea. What if its not Frankenstein like but more "siamese twin" like?

So the batteries fail on this sat and the charger on another sat, duct tape them together, run an extension cord... Yes I realize its not always going to be simple and there are no world wide standards. But its interesting to think about "siamese twin" sat work instead of the provided assumption/example of Frankenstein work.

Imagine a comsat with nearly full positioning fuel tanks and good thrusters and dead traveling wave tubes in the transmitter section or the antenna failed on deployment or whatever, duct taped to a perfectly working comsat with nearly empty positioning tanks...You may not even have to do wiring, some weird scenarios might require nothing other than two arms and a roll of duct tape, or aerospace grade kapton tape or whatever they use. I imagine just mushing them together might have some interesting thermal issues, those could be worked around, probably.

To do ANYTHING yes you'd need a full orbiting machine shop, and a full SMD rework station, and probably a solar powered foundry to make castings. But as decades (centuries?) of high tech redneck engineering proves, you can none the less do a hell of a lot with just duct tape, jb weld, and bailing wire. You can imagine this looking all liquid metal terminator 3 or whatever, but I'm thinking its gonna look a lot more "hold my beer and watch this"

Re:Strange idea

[dbIII]

So the batteries fail on this sat and the charger on another sat, duct tape them together, run an extension cord

Mir!
OK, that's not very fair to a very successful long running project, but they did have a few quick fixes along those lines that worked well.

probably a solar powered foundry to make castings

There's been a push to get casting experiments going on the ISS since before it's proposed name was settled. Maybe there is something very small along those lines already.

Re:Strange idea

[garrettg84]

I would mod you up if I had any mod points. This is exactly what I had envisioned as well. Other than the potential of more debris from space junk if a crash occurs, what would prevent this from happening?

Re:Strange idea

[Solandri]

You can't just duct tape and weld parts together to make a functioning satellite. Whenever a satellite (or spacecraft for that matter) is designed, it's one person's job to track the weight, inertia tensor, and location of every part which goes into the satellite. Yes, even the duct tape. The reason is that the overall inertia tensor of the satellite (a 3x3 matrix) has to be symmetric and oriented properly to be able to control the satellite when spinning or rotating it. If it's not, its angular momentum vector will oscillate between the axes of the minimum and maximum moments of inertia when you try to rotate or spin stabilize it, kinda like an unbalanced tire on your car, or (for a non-rotational analogy) how a marble dropped in a bowl does not automatically rest at the bottom but instead goes back and forth up the sides. The maneuvering thrusters also have to be in line with the symmetric axes of the inertia tensor. Otherwise firing them will result in a similar wobble instead of a spin (the U.S. submarines with dive planes on the conning tower are a major PITA to maneuver because the up/down force isn't in line with an inertial axis nor the center of gravity of the ship)..

To see this for yourself, take a rectangular hardcover book and hold it closed with a rubber band. Note the three possible major axes of rotation (axis goes from top to bottom, from left to right, or front to back).

If you throw it in the air spinning so it remains flat (rotational axis goes from front to back), it's stable. This is this is the axis of maximum inertia.

If you throw it in the air spinning side-to-side (rotational axis goes from top to bottom), it's also stable. This is the axis of minimum inertia.

But if you try to throw it in the air spinning top to bottom (rotational axis goes from left to right), you can't. It's unstable. Its direction of spin will oscillate between the minimum and maximum axes of inertia, like the marble going up and down the sides of the bowl. If your satellite's inertia tensor isn't preplanned and symmetric, any attempt to rotate it will cause an oscillation between its natural maximum and minimum inertia axes, essentially making it uncontrollable.

I suppose you could mount weights on your franken-satellite to symmetricize its inertia tensor, like they add weights to car wheels to balance them. But have fun weighing and measuring inertia remotely in zero g.

Re:Pentagon work

[craigminah]

So tell me where I can buy one of these cars you speak or? Still research / vaporware.

Re:Where does the money come from?

[tmosley]

Same way everyone else does it, we borrow freshly printed money from our central bank at interest.

Re:Pentagon work

[gv250]

Anyone got McGuyver's phone number? I'm sure he can get the robot to do *something* with the duct tape and swizzle stick.

Hmmm, duct tape.
Note to self: Pitch reality TV show to A&E hosted by Richard Dean Anderson and Steve Smith. Contestants must solve high-tech problems using only the household items that they are given. The items always include duct tape and empty beer cans.

Re:Pentagon work

[ZeroSumHappiness]

Hilariously, DARPA apparently created onion routing! I guess the NSA/CIA/TLA didn't realize what they were doing until it was too late.

Yes, but ...

[dbIII]

It's generally a stupid idea but there's a lot of stuff in similar orbits (eg. geostationary orbit over the US) that could mean doing it more than once with sane amounts of fuel. Of course getting to the far side of even the same orbit (eg. over Indonesia) is going to cost.

I just hope this doesn't turn into a long and pointless tranfer orbit thread populated with people that don't understand that ellipses exist (and that changing to a different location in the same orbit doesn't come for free) like the last time this came up :(

Leveraging against gravity is a fantastic tool: you don't have to worry about nudging something and then pulling it back to stop it in place

That's a very good point and reminds me of Lem's funny "Pirx the Pilot" story where the hero brought in a version of himself from the future to hold the nut while he turned the bolt in microgravity.

Re:Yes, but ...

[dbIII]

so I'm not at all sure what that's supposed to mean.

It refers to an extremely painfull earlier thread on this topic which consisted of trying to explain moving between orbits (and to different angles in the same orbit) to people that refused to consider anything other than circles so would not believe what you've written above :(
You've put it well, and you've got a point that changing phase isn't all that expensive given enough time in comparison to station keeping costs.

Re:Pentagon work

[spauldo]

DARPA promotes research. That's what it's for.

Products do not appear magically on the shelves at stores. Scientific advances do not immediately turn into things you can buy. They have to go through a research and design phase, which is what DARPA promotes. There's an engineering and application phase that follows, which DARPA isn't generally involved in. After that, there's marketing and commercialization, which is completely out of the realm of DARPA.

In the case of self-driving cars, you probably won't be able to buy one for personal use on the highway for a long, long time. In the shorter term, you may be able to ride in an automated taxi at a resort. You might see automated trucks that follow a human-driven truck on the interstate. You might see cars that can park themselves. It'll likely be a long time before you can buy a personal automated car for use on the public streets.

I've got the solution

[GodfatherofSoul]

What we need is a kind of "space truck" that can take astronauts up into space, let them live and work for weeks at a time while working on these satellites, and possibly bring them back from orbit. It would be great if this "space truck" was reusable as well. The added advantage is the government isn't beholden to foreign or private entities when we need to conduct repair or salvage operations in space.

Re:I've got the solution

[ColdWetDog]

Funny thing. The XB37 is about the size of a pickup truck.

Just sayin'.

Re:Pentagon work

[networkBoy]

Ya know... I might actually watch that. what kind of high tech problems are we talking about?

Start to worry when they build the stealth version

[petes_PoV]

This is essentially a satellite grabber. It can "dock" with a satellite, attach things to it (presumably drill holes in it, too) and make the satellite do things - either things it used to be able to do, or things you'd like it to be able to do.

One thing that would be nice to do would be to deorbit large, useless satellites that are occupying prime orbital slots. Or to add controlled destruction to satellites that failed and are out of control (though I'd be surprised if this thing could stop a tumbling satellite).

The trick is, that all of these maintenance operations are only "good" when performed with remedial intent, on your own hardware or hardware of a space-faring nation who's asked for your help. The same technology can also be used to wreck the satellites of nations you don't like. The trick is to make sure nobody sees you doing the dirty deed.

Since most satellites don't have proximity detectors, or security cameras build into them, they won't see an approaching wrecker. All that will happen is your spy-sat suddenly goes dead. If you're lucky a groundstation from an independent country might have tracked the approach of a satellite wrecker and get you some sympathy after the fact. However once the wrecker satellites become non-reflective, impose radio silence and become covered in radar absorbent material, there will be no way to tell if your "reconnaissance" bird fell silent for technical reasons or if someone else helped it die.

We're being actively misled about purpose of this

[Idarubicin]

Other posters have already observed some of the obvious flaws in this scheme.

Satellites fail, for the most part, when their rechargeable batteries quit and/or their consumable manoeuvring fuel runs out. These are among the heavier components aboard many satellites, so our hypothetical 'repair and resupply' launch is already going to be costly and heavy before you add all that unique and highly flexible hypothetical manipulator hardware. From any sort of rational economic standpoint, if you're going to launch a heavy, expensive satellite, you might as well launch a replacement (with all-new hardware, up-to-date electronics, incorporating the lessons learned from the previous iteration, etc.) instead of trying to fix or cannibalize the dodgy one in orbit.

Trying to service multiple satellites with one launch of our Swiss-Army-knife repair droid gets even worse, because manoeuvring between orbits tends to be very costly in terms of fuel (prohibitively so if a significant change in inclination is contemplated) and therefore weight.

And how user-serviceable are most satellites? Anything that's already in space now (or that is likely to be launched in the next decade) hasn't been designed to be repaired, modified, or scavenged after launch. Are we really solving the 'space junk' problem if our repair droid is inadvertently leaving behind a cloud of dropped screws and broken hardware? One satellite is easy to track and avoid. A haze of screws and plastic chips is not--and will still put a hole right through the ISS.

The folks at DARPA are sometimes crazy, but they're not usually idiots. Presumably they've been able to come up with the same objections as Slashdotters, and they probably realized them faster than we did. So what's really going on?

1) A stripped-down version of this tool could be used to attach de-orbiting or manoeuvring thrusters to disabled satellites that happened to be occupying (or threatening) particularly high-value orbital real estate. The ISS has to be periodically repositioned to avoid the occasional bit of space junk. Further up, there's a limited amount of space in geostationary orbit, and a malfunctioning satellite could be trouble as either a source of physical or radio clutter. If the program fails to produce its rather pie-in-the-sky 'dream' goal, it could still develop this useful sideline.

2) The military would love to have the capability to selectively damage, disable, and/or capture 'enemy' space hardware. This program would complete nearly all the steps required to develop such a capability, but under the shiny, happy patina of putative civilian applications.

summary wrong?

[BlackSnake112]

I thought the line was "Need parts! Kill the fat one." not kill the little one.

If they can reuse parts from older satellites or reuse the old satellites that would be a good thing. They may be able to get rid of some of the bigger "space junk" that is up there. I am not sure if anything can be done with the paint chips and other smaller parts zipping around up there. Making a space dragger like the fishing boat dragger would also "catch" useful satellites.

Re:Pentagon work

[ColdWetDog]

Self driving vehicles is probably a bad example. The tech is actually there - it's the infrastructure that's a bitch. Of course, that happens to be true for lots of tech things. Widespread adoption of a particular technology depends on much more than available hardware and software. The wetware has to be interested and available. Costs are a factor. Luck, the economy and perhaps moon phases as well.

But not to worry. The first widespread use of autonomous vehicles will likely be IED sweepers / screening patrols in a military operation. No freeways to worry about in *stan.

Re:Can we *not* do this???

[ColdWetDog]

Who the fuck modded this down?

DARPA

Exactly who do you think has unlimited mod points these days? Taco?

Re:Where does the money come from?

[ColdWetDog]

Or just export lots of expensive things. Aircraft. Giant construction machinery. Pharmaceuticals. Movies.

We are in the top three of exporting nations.

(Not to say we don't do dippy things like print money, but there are other mechanisms to generate capital. When all else fails, we start wars.)

Re:Where does the money come from?

[camperdave]

Freshly printed money? What are you, some kind of stone age, vacuum tube, hippie Mennonite or something? Some clerk at the central bank simply enters a number on a computer screen, and the funds are in your account as soon as they click OK. Paper money... Phhhft!

Re:We're being actively misled about purpose of th

[ColdWetDog]

1) A stripped-down version of this tool could be used to attach de-orbiting or manoeuvring thrusters to disabled satellites that happened to be occupying (or threatening) particularly high-value orbital real estate. The ISS has to be periodically repositioned to avoid the occasional bit of space junk. Further up, there's a limited amount of space in geostationary orbit, and a malfunctioning satellite could be trouble as either a source of physical or radio clutter. If the program fails to produce its rather pie-in-the-sky 'dream' goal, it could still develop this useful sideline.

I think this is the real reason, at least in the beginning. Prime orbital slots are getting scare and you can't make new ones. Getting RID of the junk by deorbiting the stuff makes sense, is technologically feasible and doesn't require the tool waving and silly economics of bringing duct tape to low earth orbit.

Of course, EVENTUALLY you need to learn how to fix things in orbit. The ISS and the Shuttle / Hubble repair missions have shown that we can do baby steps but we need to develop capabilities far in excess of what we have now. You're not going to make much progress if it takes you a year to choreograph a repair mission that very nearly got sidelined by an errant bolt.

Re:Pentagon work

[MyLongNickName]

Okay, let's try

* GPS
* Stealth Technology
* Materials that are currently used in electronics today
* Real-time voice to text translation
* Advances in certain types of lasers

Your argument is basically that spending on future tech has a high failure rate. To that I say "duh, of course it does".
 

Re:Pentagon work

[craigminah]

Insuring them and adjudicating accidents would both be huge concerns as well.

Re:Pentagon work - Junk Drawer Wars

[Webcommando]

Note to self: Pitch reality TV show to A&E hosted by Richard Dean Anderson and Steve Smith. Contestants must solve high-tech problems using only the household items that they are given. The items always include duct tape and empty beer cans.

Maybe they can call the show "Junk Drawer Wars"

Call the Cheyene Mountain Complex

[RobertLTux]

last i heard he retired to PT-593 or something so he might be a bit slow in responding

Re:We're being actively misled about purpose of th

[loners]

Number 1 already happened. Out of control comm satellite in Geosynchronous orbit.

Number 2 look up the orbital express darpa project. It was accused by a retired Russian general of being the cause the iridium crash a few years back.

Isnt it possible to just use their mass?

[Marrow]

If you send up a launch vehicle, and have it latch onto an existing orbiter, cant you use something to push the old satellite towards Earth. And push yourself into a higher orbit? It seems like it might be more efficient than hurling matter out of booster engines. You could use electromagnetic force.
Can you use pre-existing orbiters as "stepping stones"?

Re:Where does the money come from?

[AdamHaun]

Where do you guys get the money to pay for all this?

Taxes. The United States GDP is almost $15 trillion. This sort of exotic-sounding stuff is http://www.usgovernmentspending.com/budget_pie_gs.php, proportionately. The real expenses are proportional to the size of the population (and military).

It looks like the world's largest welfare state but I can't see how the money loop gets closed.

Same way it gets closed in the private sector. There's nothing magical about government revenue and spending vs. corporate or individual revenue and spending.

It's not worth it

[mk1004]

The electronics have a limited lifetime, the satellites probably have no maneuvering fuel, and aren't designed to be taken apart or refueled.

Use an ion-drive, solar powered 'tug' that goes from LEO to Geo-stationary orbit. Take a new satellite up, drop it off, find the nearest dead satellite, and use the tug to de-orbit the satellite as it returns to LEO. Using an ion-drive vehicle keeps refueling costs for multiple missions low.

Re:Pentagon work

[Apothem]

Hell, even the failures tend to produce valuable information when it comes to projects like these. Think of all the spin-off stuff that was created simply because of NASA research?