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Space ISS Transportation Technology

New System Propels Satellites Without Propellants 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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New System Propels Satellites Without Propellants

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  • So these work like magnetic torquer bars?

    • Re:MTBs (Score:5, Informative)

      by Yoda222 ( 943886 ) on Monday August 19, 2013 @09:33AM (#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

  • Phew! (Score:5, Funny)

    by pr0nbot ( 313417 ) on Monday August 19, 2013 @08:56AM (#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! (Score:5, Funny)

      by bondsbw ( 888959 ) on Monday August 19, 2013 @09:09AM (#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! (Score:5, Funny)

        by gman003 ( 1693318 ) on Monday August 19, 2013 @09:22AM (#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.

        • by Nimey ( 114278 )
          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.
          • by tibit ( 1762298 )

            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.

            • by Nimey ( 114278 )
              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
              • by tibit ( 1762298 )

                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.

            • 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...

              • 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 youtub
                • 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.
                • by pagej97 ( 908732 )
                  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).
                  • 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.
              • 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 ma

          • by GNious ( 953874 )

            Struts - they are what makes Space Flight possible!

        • More strutz!

        • by Yvanhoe ( 564877 )
          Which is just hilarious.
    • 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 conve

    • "Yeah, bitch! Magnets!" - Jesse Pinkman
  • Old news (Score:5, Funny)

    by oodaloop ( 1229816 ) on Monday August 19, 2013 @09:01AM (#44606495)
    This technology has been used in hoverboards since at least 2015.
  • Magsails? (Score:4, Interesting)

    by shawnhcorey ( 1315781 ) on Monday August 19, 2013 @09:08AM (#44606521) Homepage
    Why don't they just use magsails []?
    • Re:Magsails? (Score:4, Interesting)

      by interkin3tic ( 1469267 ) on Monday August 19, 2013 @10:23AM (#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.

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

          • by HiThere ( 15173 )

            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.

        • 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.

          • 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] [] on it, so yes, NASA thinks it may work.
    • Or mainsails. 1500 kN, baby!
  • From the article (Score:5, Informative)

    by Grantbridge ( 1377621 ) on Monday August 19, 2013 @09:17AM (#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.
    • by mcrbids ( 148650 )

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

  • by Karmashock ( 2415832 ) on Monday August 19, 2013 @09:20AM (#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!

    • by Urkki ( 668283 ) on Monday August 19, 2013 @09:31AM (#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?

      • 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.

  • by vadim_t ( 324782 ) on Monday August 19, 2013 @09:20AM (#44606583) Homepage

    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.

    • 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?

    • You can maneuver with reaction wheels and a charged tether []. 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: (Score:3, Interesting)

      by ninjabus ( 3024459 )
      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.
  • 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!

  • 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

  • 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

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

  • Tank Farm Dynamo [] by David Brin (1983)

  • 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.
  • I was immediately taken by how RINGS [] resembles a fictional spaceship [].

  • Isn't something that PROPELS an object, by definition, a PROPELLANT?

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