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New System Propels Satellites Without Propellants

samzenpus posted about 8 months ago | from the gliding-into-the-future dept.

Space 85

cylonlover writes "Astronauts on the International Space Station (ISS) are testing a new propulsion system ... inside the station. While this might seem like the height of recklessness, this particular system doesn't use rockets or propellants. Developed in the University of Maryland's Space Power and Propulsion Laboratory, this new electromagnetic propulsion technology called the Resonant Inductive Near-field Generation System (RINGS) uses magnetic fields to move spacecraft as a way to increase service life and make satellite formation flying more practical."

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85 comments

MTBs (2)

nicholasjay (921044) | about 8 months ago | (#44606467)

So these work like magnetic torquer bars?

Re:MTBs (5, Informative)

Yoda222 (943886) | about 8 months ago | (#44606677)

MTB generate only torque. Here they speak of propulsion system. But if I understand correctly the article, it's more about changing the relative position/attitude of two (or more) spacecraft than "real" propulsion of one spacecraft alone. It's a technology for formation flying

Re:MTBs (2)

Electricity Likes Me (1098643) | about 8 months ago | (#44607411)

It can also work with planets though. Earth has a magnetic field, so by pumping current (or sinking it) you can increase and decrease orbital height relative to the planet.

Re:MTBs (1)

DerekLyons (302214) | about 8 months ago | (#44608605)

It can also work with planets though. Earth has a magnetic field, so by pumping current (or sinking it) you can increase and decrease orbital height relative to the planet.

Those are called electrodynamic tethers [wikipedia.org].

THat's nothing (3, Interesting)

goombah99 (560566) | about 8 months ago | (#44609555)

THis is just changing the orientation of subunits and spacing of subunits without changing the center of mass. It would not seem magical if theywere connected by gears. Here they are doing it with magnetic coupling. But there's no "propulsion" since that implies changing the center of mass.

the chinese have a method for massless propulsion however:

http://www.wired.com/dangerroom/2008/09/chinese-buildin/ [wired.com]

Re:THat's nothing (1)

SuricouRaven (1897204) | about 7 months ago | (#44612039)

Let them. If it doesn't work, they'll have wasted a few million dollars on testing. If it does, then the tech isn't hard to reproduce and everyone will be manufacturing them soon after.

Re:THat's nothing (0)

Anonymous Coward | about 8 months ago | (#44624649)

...and the US will be whining that they've copied Chinese technology without licencing it! Or does that only work when it's the Chinese copying US technology?

Re:MTBs (-1)

Anonymous Coward | about 8 months ago | (#44607213)

Hey I like the photo in the article. Complete with the Asian woman with small (of course) yet somehow saggy tits!

I mean she's Asian so of course she has small tits. Her man probably has a small penis. But no really they're down to her waist. You know you checked this out and you know I am right.

Phew! (4, Funny)

pr0nbot (313417) | about 8 months ago | (#44606469)

"While this might seem like the height of recklessness, this particular system doesn't use rockets or propellants" ... just magnetic fields, so that's ok then, good think there's no electronic equipment up there or anything!

(I'm sure they know what they're doing, it's just that the summary seemed retarded.)

Re:Phew! (5, Funny)

bondsbw (888959) | about 8 months ago | (#44606533)

As an expert at Kerbal Space Program, I can say for sure that using such a system will result in crashing into the nearest moon. As does everything.

Re:Phew! (4, Funny)

gman003 (1693318) | about 8 months ago | (#44606591)

As a KSP player, I'm impressed that you manage to get all of your craft out of the atmosphere without destroying themselves. Hell, some of mine collapse on the launch pad.

Re:Phew! (2)

Nimey (114278) | about 8 months ago | (#44606711)

You want the EAS-4 strut connector; use it to tie each stage's parts together and they're much less likely to collapse.

I did up a mock-Saturn V and had to to a crisscross (top outer tanks to next-lower central tank) with struts on the second stage between the central stack and the top tanks on the four side stacks, because otherwise the four top-outer tanks tended to break off around 3-5km altitude, which completely broke the second stage.

Re:Phew! (1)

tibit (1762298) | about 8 months ago | (#44606995)

You're probably reaching max-Q (maximal aerodynamic pressure) at that point. Pull back on the throttle and you should make it without the struts.

Re:Phew! (1)

Nimey (114278) | about 8 months ago | (#44607167)

I don't think it was that, because pre-crisscross strut those tanks were oscillating almost from launch, it was just at altitude when they overstressed. Besides, I told Mechjeb to keep it to terminal velocity. :P

Re:Phew! (1)

tibit (1762298) | about 7 months ago | (#44611327)

Turn mechjeb off and see what it does. Mechjeb's own control loops sometimes happen to oscillate at the frequency of one of the natural frequencies (modes) of the stack.

Re:Phew! (1)

bluefoxlucid (723572) | about 8 months ago | (#44607473)

So is this a game where you design and pilot rockets, and the simulator is good enough that you armchair engineers and armchair astronauts who don't know wtf you're doing predictably can't get off the ground?

Because there's also a game called Spice where you can build bitchin' guitar amps...

Re:Phew! (1)

chuckinator (2409512) | about 8 months ago | (#44607895)

I was ecstatic the first time I pulled off a successful Apollo-style moon landing and return home mission, but it took nearly 4 hours realtime for the rocket design and flight. Flying places isn't too bad, but docking is the most god awful difficult part of any game I've ever played. I've thought about doing gameplay videos, but I would need to brush up on my video editing to cut it for time and add voice overs. My typical gaming session has too many uttered profanities to leave the mic open for a youtube video.

Re:Phew! (1)

chuckinator (2409512) | about 8 months ago | (#44607919)

Should have got this in the first post...

While the article mentions formation flying, which is important, I imagine that the real world application of the magnetic repulsion/attraction tech is going to be more useful for docking together large spacecraft assemblies in orbit. It would have made it much easier to link up the ISS that way.

Re:Phew! (1)

pagej97 (908732) | about 7 months ago | (#44612079)

Docking's not bad once you get the hang of it. Use the navball to figure out relative velocity and position, and keep your two docking ports pointing at opposing normal vectors (using the ASAS system).

Re:Phew! (1)

chuckinator (2409512) | about 8 months ago | (#44618895)

My problem was more along the lines of not having the RCS thrusters placed well, and it took a few tries to figure that out. I was fine using the clusters for adjusting attitude for a while, but changing position relative to the other craft didn't work well until I fixed the design flaw.

Re:Phew! (1)

artfulshrapnel (1893096) | about 8 months ago | (#44620291)

It's at least good enough to teach some of us armchair astronauts a bit more about engineering and orbital mechanics!

And yeah, if you want to be reliably successful at it you have to go and learn at least some of the core concepts of the related fields of engineering and physics. There are some crib sheets and whatnot online (like delta-v charts and optimal orbital insertion guide tables) but they still require that you understand things like delta-v and design your ships in a way that puts the center of mass, aerodynamic resistance and control points in the right places.

If you want to do less orbital mechanics calculations you can get the MechJeb autopilot that does a lot of the basic work for you (as seems to be the preferred method lately among real-world satellite launches). It won't figure out things like orbital transfer sequences or slingshots or anything really complex. What it will do is get your orbit perfectly circularized (or properly elliptical), help you rendezvous with another orbital object, hold your orientation along some orbital axis (prograde, retrograde, etc) or help control a descent burn so you hit a given target location.

Re:Phew! (1)

bluefoxlucid (723572) | about 8 months ago | (#44607427)

It's too much exposure to American-style journalism. One day we'll all talk like this.

Speaking of talking, I saw your girlfriend at the mall talking to two boys the other day. Wait until you find out what was said! It seemed like the perfect setup, two tall, well-chiseled college boys with one smokin' hot blonde. This was the scene at the Sears, when Mary Beth needed to find a new iron. The girl's shopping trip was interrupted when the first possibly well-hung boy approached him, striking up a conversation. Before long, he offered to call a friend; and that's when the second steel-hewn adonis joined the conversation. The first saleman was so incompetent that he had to call another salesman to figure out how to close up an extendable ironing board.

Re:Phew! (0)

Anonymous Coward | about 8 months ago | (#44607733)

Speaking of talking, I saw your girlfriend at the mall talking to two boys the other day.

Sounds like she is giving your dads some parenting advice.

Re:Phew! (0)

Anonymous Coward | about 8 months ago | (#44607441)

You mean they weren't testing cryogenic engines in the tight confines of their oxygen rich environment!

Flying saucers are coming! (-1)

Anonymous Coward | about 8 months ago | (#44606475)

Now if only there were some earth, solar system, and galactic sized magnetic fields to tap we'll be able to make ugly assed flying saucers.

Magsails? (3, Interesting)

shawnhcorey (1315781) | about 8 months ago | (#44606521)

Why don't they just use magsails [wikipedia.org]?

Re:Magsails? (3, Interesting)

interkin3tic (1469267) | about 8 months ago | (#44607121)

The wiki article says those are merely proposed. This sounds closer to being a real thing. Why would they prefer a purely fictional technology?

Also, TFA mentions

According to an MIT study [PDF], when EMFF is perfected, it will have a wide number of applications including interferometers, space telescopes where each satellite carries a section of mirror, generating artificial gravity, creating a magnet shield against solar radiation storms, and clearing space debris by using their spin to toss the debris into a safer trajectory.

It sounds like this is useful for pushing stuff around in space at near distances, including non-autonomous propulsion such as junk, while magsails are (in theory) useful for moving only the cargo around over large distances, at slower accelerations.

Re:Magsails? (2)

shawnhcorey (1315781) | about 8 months ago | (#44607281)

They're the same thing but a magsail has way more power. And all technology was nothing but an idea at one time.

Re:Magsails? (1)

bluefoxlucid (723572) | about 8 months ago | (#44607507)

I have this idea where we use a twig cut from a white ash to locate water by holding it above the ground and walking.

We should use that to prospect for oil.

Re:Magsails? (1)

HiThere (15173) | about 8 months ago | (#44609329)

Don't know about that, but I used a similar idea a couple of times to locate broken pipes. It saved a BUNCH of digging, as I had no idea where the break was. (Yeah, the place it indicated was a reasonable place, but I hadn't figured that out until AFTER I dug up the pipe..)

My guess is that it taps unconscious estimations. This doesn't mean it doesn't work better than chance.

Re:Magsails? (1)

interkin3tic (1469267) | about 8 months ago | (#44608325)

They're the same thing but a magsail has way more power.

Again, I've only skimmed the wiki article, but it sounds like this can push other objects away, while a magsail can only move the cargo that it is on. In other words, if you had a sattelite and a bit of junk was moving towards it to destroy it, this thing could push the junk away while the magsail could only move the satellite out of the way of the junk. So, no, it doesn't sound at all like the same thing.

And all technology was nothing but an idea at one time.

Well yes, but this thing is MORE THAN AN IDEA RIGHT NOW, while the sail doesn't appear to be.

Re:Magsails? (1)

shawnhcorey (1315781) | about 8 months ago | (#44608475)

You could use a magsail to push items away, at least, any item you can induce a current in. And I do believe there were a few prototypes tested. Anyway, here's a NASA paper [PDF] [usra.edu] on it, so yes, NASA thinks it may work.

Re:Magsails? (0)

Anonymous Coward | about 7 months ago | (#44612153)

So they've invented a deflector shield from Star Trek?

Reliance on magnetic fields? (-1)

Anonymous Coward | about 8 months ago | (#44606529)

Sounds like this is basically only useful to help maintain a low-power consumption orbit of heavenly bodies with strong magnetic fields(aka just earth in our solar system).
As in it wont work at all, when removed from the earths magnetic field.

Re:Reliance on magnetic fields? (4, Informative)

Captain Hook (923766) | about 8 months ago | (#44606589)

Sounds like this is basically only useful to help maintain a low-power consumption orbit of heavenly bodies with strong magnetic fields(aka just earth in our solar system).

You are right, but there are currently about 6000 man made satellites in orbit (only about half of which are functional) and only 70 odd probes which go beyond earths magnetosphere so it's not like a huge number of vehicles couldn't use this technology. Especially since Satellite life times are normally limited by propellant they can carry

Also, just off the top of my head Jupiter and Saturn have magnetospheres.

Re:Reliance on magnetic fields? (1)

gsgriffin (1195771) | about 8 months ago | (#44607053)

Sounds like they'd be better off just figuring out how to put a gas station in space and have all the of the satellites simply stop for a fill up from time to time. Can you imagine the fuel prices at that pump?

Re:Reliance on magnetic fields? (1)

bluefoxlucid (723572) | about 8 months ago | (#44607523)

That's the idea, except the gas station is called Sol and it's supplying fuel to everywhere remotely.

You dufus.

Re:Reliance on magnetic fields? (0)

Anonymous Coward | about 8 months ago | (#44608193)

Because that requires satellites to leave their working orbit for refuelling.

Re:Reliance on magnetic fields? (1)

gsgriffin (1195771) | about 8 months ago | (#44616971)

Just getting harder and harder to say something with tongue in cheek on /. without people trying to take it literal. Geesh...my nerd friends really are lacking in any creative thought related to humor. I'll spell it out next time and put something at the end that says, "This is a joke. Please reserve your derogatory comments for those that are seriously stating something silly. This is meant to be silly and absurd. If you take it literally, you are a dufus.

Re:Reliance on magnetic fields? (1)

fuzzyfuzzyfungus (1223518) | about 8 months ago | (#44606607)

Sounds like this is basically only useful to help maintain a low-power consumption orbit of heavenly bodies with strong magnetic fields(aka just earth in our solar system). As in it wont work at all, when removed from the earths magnetic field.

It certainly isn't an unobtanium reactionless thruster, which would be nice; but given the economic importance of nearish-earth satellites, giving them a lifespan limited only by solar panel decay and/or technical problems, rather than propellant load, is a pretty nice little upgrade.

Re:Reliance on magnetic fields? (1)

bluefoxlucid (723572) | about 8 months ago | (#44607535)

There is no solar panel decay in space.

Re:Reliance on magnetic fields? (0)

Anonymous Coward | about 8 months ago | (#44609339)

Solar panel decay is much faster in space than on the ground, anywhere from a factor of 2 to an order of magnitude worse depending exactly where and what kind of solar panel you use. Radiation damage can reduce light transmission of any covering, and increases leakage currents. Thermal cycling and UV damage can at least be designed around to some degree, limiting your choice of what materials to use. Without other bottlenecks, and if limited on how much initial excess capacity you could build into an array, decay would limit operations to a time scale on the order of a decade.

Re:Reliance on magnetic fields? (2)

Yoda222 (943886) | about 8 months ago | (#44606695)

From what I understand in the article, it's a technology for formation flying. You can generate your own magnetic field anywhere, using one of the spacecraft, and use this "non-natural" magnetic field from one of the other spacecrafts.

Re:Reliance on magnetic fields? (2)

nedlohs (1335013) | about 8 months ago | (#44607561)

No, maybe you should try reading the article?

It has nothing to do with actual propulsion (despite the title) - just changing the relative positions of groups of satellites without changing the center of mass of the group. External (nonuniform) magnetic fields would cause problems (I suspect anyway) making the task more difficult and limiting just how far apart things can get while still using this system.

From the article (4, Informative)

Grantbridge (1377621) | about 8 months ago | (#44606565)

"Electromagnetic formation flight (EMFF) gets around this propellant problem by turning the satellites in a formation into electromagnets. By using a combination of magnets and reaction wheels, spacecraft in formation can move and change their attitude and even spin without propellant. Satellites can change their polarity to attract or repel one another, turn, or shift their relative positions in any manner that doesn't require changing the center of gravity for the entire formation." So its all about formation flying, the satellites will pull/push off each other to remain in the correct formation. They will still needs propellent to move the whole cluster, but they can stay in formation without using any fuel.

Re:From the article (1)

mcrbids (148650) | about 7 months ago | (#44611167)

I think most of us here thought this was something like using an Electrodynamic Tether [wikipedia.org] which allows for considerable maneuvering capability without the use of any propellant whatsoever. Maybe reading TFA before forming an opinion might be advisable?

Not as exciting as it sounds (3, Informative)

Karmashock (2415832) | about 8 months ago | (#44606581)

Very cool technology but its not a reactionless drive sadly. The magnets merely allow a swarm of sats to hold a formation in relation to each other.

Oh well... darned laws of physics getting in the way again!

Re:Not as exciting as it sounds (3, Interesting)

Urkki (668283) | about 8 months ago | (#44606649)

Very cool technology but its not a reactionless drive sadly. The magnets merely allow a swarm of sats to hold a formation in relation to each other.

Oh well... darned laws of physics getting in the way again!

Well, good thing it is not reactionless... I mean, if it were reactionless drive, then it would just move the Earth without moving the spacecraft, and what good would that be?

Re:Not as exciting as it sounds (1)

Karmashock (2415832) | about 8 months ago | (#44606731)

My understanding of the term, is that it would be a drive that functioned without propelling any matter away from the vector of thrust.

So far as I know, that is physically impossible which is why it remains in the realm of science fiction. But when I saw the title of the article, I got excited because that would be a hell of a discovery. Sadly it is not to be... still cool though.

Re:Not as exciting as it sounds (1)

MOSFET Explosion (2849381) | about 8 months ago | (#44610827)

Reaction-less thrust would appear to be not only possible, but something that's in active development!

Here's the site for the group that's working on it: http://www.emdrive.com/ [emdrive.com]
And here's the relevant research paper: http://www.newscientist.com/data/images/ns/av/shawyertheory.pdf [newscientist.com]

Re:Not as exciting as it sounds (1)

Karmashock (2415832) | about 7 months ago | (#44612463)

The drive in question appears to be a hoax. The tech was apparently "Developed" in 2006 and has not been submitted for international scientific scrutiny. It has also not been used. Every paper not submitted in chinese has been torn apart for errors.

Don't get me wrong. I want it to be real. But this doesn't appear to be real.

Cool, but not as awesome as the headline says (3, Informative)

vadim_t (324782) | about 8 months ago | (#44606583)

This is for positioning satellites relative to each other. The applications are things like telescopes made of several spacecraft to create a mirror larger than what is practical to launch in one piece.

But this isn't an engine that will allow a satellite to stay in orbit without fuel. They still need a traditional engine with propellant for everything besides adjusting the distance between nearby satellites.

Re:Cool, but not as awesome as the headline says (1)

captainpanic (1173915) | about 8 months ago | (#44607467)

Well, if they have a strong electromagnet, shouldn't that create a magnetic force within the earth's magnetic field (although perhaps quite small)? I mean, two magnets either attract, repel, right?

Re:Cool, but not as awesome as the headline says (1)

X0563511 (793323) | about 8 months ago | (#44607481)

You can maneuver with reaction wheels and a charged tether [wikipedia.org]. You likely could get away with the most massive (ideally central) satellite using this, and the rest can be "pulled" using this new system relative to it.

It sounds like this whole scheme would then be limited by the power storage capacity of the satellites. Lots of solar, good batteries, or maybe RTGs (though not sure how much that would be accepted, in orbit)

Re:Cool, but not as awesome as the headline says (1)

Richy_T (111409) | about 8 months ago | (#44608473)

I wonder if this could also be used to pass around power from the "mothership"

Re:Cool, but not as awesome as the headline says (3, Interesting)

ninjabus (3024459) | about 8 months ago | (#44607753)

It's actually extremely awesome. Lets say a group of satellites is falling out of position. We could launch a single 'anchor' satellite loaded to the brim with propellant which would be able to effectively stabilize the rest of the constellation. That means the rest of the satellites can be launched with less propellant, making the system simpler and costs lower for everyone.

Also generates power (1, Troll)

Gothmolly (148874) | about 8 months ago | (#44606597)

Either you use the magnetic field to move your ship, or you use the difference in potential across long wires to generate power.

This is robbing energy from the Earth to move the space station. Quick, someone call Al Gore!

Is it just me... (0)

Ronin Developer (67677) | about 8 months ago | (#44606601)

Or, does everybody else think the guy in the picture is scared to death of the terminator like spacecraft floating around the cabin?

Also...why has it (apparently) taken us almost 65 years to make our own working versions of the propulsion systems used by the alien spacecraft that crashed in Roswell and stored in Area 51? Huh?

Actually, this is pretty cool. Now, the bigger question is whether these devices will be able to maneuver in open space or will they require a magnetic field (Earth, stellar, etc) to function? What is the, theoretically, maximum "thrust" and velocity these craft will be capable of achieving?

Stargate Anyone? (1)

TFlan91 (2615727) | about 8 months ago | (#44606913)

Rings? Cmon? I can't be the only one who instantly makes this connection...

As with any technology, wait until the public gets its' hands on it. I can easily see this type of propellant being used in roads, elevators, in our shoes (fuck stairs - we Americans are lazy)... this will be fun

Re:Stargate Anyone? (0)

Anonymous Coward | about 8 months ago | (#44607183)

Yes! My first question was what single malt scotch were they drinking when
the guy in the corner, who was three sheet to the wind, arose from his stupor
and said "We should call it RINGS....."

So, explain to me again... (1)

gestalt_n_pepper (991155) | about 8 months ago | (#44607511)

Why we can't do this more simply with gyroscopes and an electrodynamic tether?

Re:So, explain to me again... (0)

Anonymous Coward | about 8 months ago | (#44608145)

Simple science, Ok, let's go over the design again, see... there's a rubber band with one end attached to the inside of the satellite. Tthe other end is tied to a piece of metal. An electromagnet gets energized as the satellite goes around the planet pulling on the piece of metal tied to the other end of the rubber band. This causes the rubber band to stretch. When the electromagnet is turned off it releases stored kinetic energy in the rubber band. For every action there's an equal but opposite reaction.

Propel Without Propellant? (0)

Anonymous Coward | about 8 months ago | (#44608371)

A propellant, by definition, it anything that propels.

So how the hell do you propel without a propellant?

Stretching definitions in the headline (0)

Anonymous Coward | about 8 months ago | (#44608779)

This is a "propulsion system" if you assume that other satellites are your reaction mass. Let's see how effective it would be to get to the Moon by flinging satellites out the back of the spacecraft.

Sounds like a light-saber training program (1)

AlphaBit (1244464) | about 8 months ago | (#44609759)

Propellant-less floating robot on a spaceship? There must already be footage of the thing floating around with a laser pointer attach and the astronauts swinging tools while making light-saber noises. At least that's what I would do.

New System Propels (0)

Anonymous Coward | about 8 months ago | (#44609855)

Interesting. Opens up the possibility of an orbital tug boat. The real satellite can be moved around the tug boat.

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