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Programmable Magnets 120

Martin Hellman writes "A few weeks ago Popular Mechanics awarded one of its Breakthrough Awards for the invention of 'programmable magnets.' Instead of having a single North or South pole, these clever devices have an array of North and South poles. If a matching device with exactly the same array is aligned with the first one, they will experience strong repulsion, just like two single North poles do when brought near one another. If the matching device has the complementary array (North and South interchanged), with correct alignment the two devices will attract. But a slight misalignment will cancel most of the force. Other configurations are possible as well, allowing frictionless magnetic gears and exploding toys. The inventor, Larry Fullerton, used techniques similar to those from CDMA modulation. (Watch the intro video for a brief explanation. While I don't understand magnetism that well, I do understand CDMA and carrying over those ideas to magnetic arrays does make sense to me.)"
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Programmable Magnets

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  • Obligatory: (Score:5, Funny)

    by Even on Slashdot FOE ( 1870208 ) on Friday October 22, 2010 @09:16AM (#33984530)

    Effing magnets - how do they work?

    • Re:Obligatory: (Score:5, Informative)

      by Myopic ( 18616 ) on Friday October 22, 2010 @09:24AM (#33984570)

      Some people will need to be told about the joke [].

    • Re: (Score:2, Funny)

      Magnetism is a gift from God. Do not believe the filthy scientists who wish to destroy your faith in God by "explaining" magnetism by science. It is a trick.

      Every time you experience magnetism, smile, and know that you are feeling the gifts of the Holy One. And never forget: to use your mind is to go against the will of God.

      • If using our mind is going against the will of God then why did God give us a mind in the first place?

        • You're doing it!

        • Because he is a narcissistic bastard who wants us to worship him through our own decision. Not much fun in being adored by a puppet.

        • Re: (Score:1, Troll)

          Because there is no god. Also, wooosh.

        • Don't you know? It's all a test. He also planted fossils and arranged the laws of nature to simulate an approximately 14 billion year old Universe and approximately 4.5 billion year old Earth. In short, everything you see, hear, smell, touch, taste, and think is a lie. Only if you ignore all evidence that comes your way and believe everything that some guy tells you about a book that has been re-translated and re-interpreted a million times over the past two thousand or so years can you find the real tru

      • s/"gifts of the Holy One"/"touch of the noodly appendage"/ FTFY
    • Re: (Score:3, Insightful)

      by blueg3 ( 192743 )

      Magnetic fields do no work.

    • Effing magnets - how do they work?

      They don't. It's actually all a giant conspiracy to make people believe that Earth has a magnetic field so Electromagnetistists can get funding. Global Warming Conspiracy is an offshoot of it.

    • FROM CORRELATED MAGNETICS RESEARCH LLC: The volume of interest generated by this post and the Popular Mechanics Breakthrough Award has temporarily shut down our web server. Upgrading the server today to bring it back online. Please check website later today for more information on programmable magnets. "The nation that controls magnetism, will control the universe!" -Diet Smith 1947
  • If my theories are ultimately correct, this is but one small step toward realizing long-distance space travel. Using huge magnets to repel a craft long distances is the answer. It's crazy, I know.

    • by Haedrian ( 1676506 ) on Friday October 22, 2010 @09:27AM (#33984588)
      I don't think so. I think huge magnets will increase the mass of the spacecraft needlessly - and you'll still be using around the same amount of energy which you could use if you use fuel or whatever. Unless of course we put a ton of magnets around the solar system and we launch spacecraft in a manner similar to railguns.
      • Re: (Score:3, Interesting)

        by Tildedot ( 137711 )

        Railguns are nice, and would work for materials that could stand the strain of a Super-G acceleration.
        Sadly, most people don't fit into that category.

        I know! How about a maglev loop and a high mountain?

        Evacuate most of the atmosphere from a track built as giant loop of pipe with a tail, something like the figure 6 (or 9, in Australia :^), except very, very large. Point the tail up the side of a tall mountain. Magnetically suspend the craft in the pipe, accelerate past escape velocity at a rate of 1-2Gs,

        • Re: (Score:3, Insightful)

          The acceleration from speeding up in the loop wouldn't be the only acceleration in the system. A circular track would create centripetal acceleration as well. If I remember physics correctly, the radius of the loop is given by R = v^2 / a. If v is the escape velocity (11.2 km/s) and a is 20 m/s^2 (about 2G), we get a loop with a radius of 6272 kilometers.

          Then again, I'm no physicist, so feel free to correct me.

          • by Amouth ( 879122 )
            while that is correct for the surface - escape velocity is a lot lower the higher you get - if you could use something like this to get into LEO then burn your way to an escape velocity.. think of sling-shotting a bottle rocket.

            my big question would if you are going to accelerate it in a vacuum - somehow you have to avoid the bug on a windshield effect once you let go and put it in the air..
            • If you're going to build a tube thousands of kilometers in radius, why not just keep going and extend it towards orbit while you're at it? We're only talking another few hundreds of kilometers of tubing.
              • by shish ( 588640 )
                And then if you're going to build a structure where the end of the pipe is outside the atmosphere, why not just build an elevator?
          • Re: (Score:1, Insightful)

            by Anonymous Coward

            The radius of earth is about 6300 km. What a cool coincidence! No, wait, it's not. If you orbit mother Earth just above the equator, what's your velocity? 11.2 km/s. Right, it's escape velocity, by the very definition of it. Your centripetal acceleration exactly cancels gravity, so you experience weightlessness in orbit. If you can double your velocity while staying on the same orbit, you will have twice as much centripetal acceleration, and experience acceleration of precisely 1G, only in the opposite dire

        • Re: (Score:3, Interesting)

          by AaxelB ( 1034884 )
          Or, combining the two ideas (and having more fun with the less realistic scale), have a ton of magnets around the solar system to form a maglev loop! You can start near the sun, then spiral out as you get faster, and then you have essentially a railgun (as the tail of the 6) to aim you out of the solar system.

          Of course, we could probably just do the railgun the size of the solar system... when it's that large, you don't need to accelerate very quickly, since you have plenty of time to get to top speed. Als
          • First - we should use some sneaky diplomacy to convince them to build a rail-decelerator - otherwise we might be able to shoot them hard, but our invasion force will be part of the kinetic payload.
            • by AaxelB ( 1034884 )
              I was assuming we'd just bombard them at range... you know, use the railgun as a railgun. I have to imagine it wouldn't be *that* hard to destroy a star (I have to imagine it because it would just be so awesome).
              • by Yvan256 ( 722131 )

                It's not that hard to destroy a star if you have two stargates and the known coordinates of a black hole.

      • by geekoid ( 135745 )

        Don't be stupid. That's why you would use a lot of a little magnets. Moron~

    • by Wireless Joe ( 604314 ) on Friday October 22, 2010 @09:48AM (#33984720) Homepage
      I've already created this, but in reverse; I have a spaceship with two magnets; one weaker one in the nose cone, and one stronger one that hangs out in front of the ship on a pole and a string. The stronger magnet pulls the weaker one up toward it, generating lift, which moves the rocket through space. Limitless free propulsion!
    • Hopefully someone with deeper knowledge can answer.

      I don't believe it has good application for space travel, in of itself. But doesn't this open the door for dramatic electric motor efficiency improvements? With many traditional motor designs, you wind up with a stagged NSNSNS design. And when the stator is half way between poles, resistance is naturally introduced, requiring an electrical impulse to offset the natural repulsion imposed by like poles. With these magnets, can you minimize the repulsion as th

      • by Simon80 ( 874052 )
        I don't think you can change or fix any of that stuff with a special spatial arrangement, but the different force/distance curve exhibited by these arrangements probably has implications for efficiency.
      • by Thing 1 ( 178996 )

        in of itself

        Missing an "and"

      • by Thing 1 ( 178996 )

        and a complimentary impulse controller

        "That's a very nice impulse you have there!"

  • by AttillaTheNun ( 618721 ) on Friday October 22, 2010 @09:27AM (#33984592)
    I can finally complete my perpetual motion machine!
  • Super useful (Score:3, Insightful)

    by captainpanic ( 1173915 ) on Friday October 22, 2010 @09:29AM (#33984606)

    Before becoming the standard critical slashdotter, I'd like to start positive: I think it's really cool - I believe that, as the video says, there are many applications for these magnets.
    The youtube video is worth the time too...

    That said, I wonder if the magnets are stable in time. some of the applications described do not allow for failures after a few months/years.
    Hope that the costs of the magnets will drop soon too...

    • by skids ( 119237 )

      These materials tend to be stable as long as their temperature is controlled and they are not subjected to an external (extremely) intense magnetic field. They aren't strong enough to demagnetize another smaller magnet of the same type (which is a reason why you have to heat them to program them).

      It's nice to see some smarter applications for magnets being thought about. It's hardly ground-breaking research, but so many times there is such a deep chasm between the throbbing brains of research laboratories

    • by geekoid ( 135745 )

      I can answer that for you:

      Yes, they are stable in time, so NO, you can't use them for your time travel machine.

  • by Ryanrule ( 1657199 ) on Friday October 22, 2010 @09:30AM (#33984612)
    Sounds like a research goal in Alpha Centauri. I am pleased.
  • by denzacar ( 181829 ) on Friday October 22, 2010 @09:31AM (#33984618) Journal

    Weren't those called firecrackers and fireworks?

    Or are we talking more like filling a bag with hydrogen and throwing matches at it?

    • I think we're talking more like "Buckaroo" and "Pop Up Pirate" level of violence rather than incendiaries, ie this would be like spring loaded toys but without the springs.

    • Re:Exploding toys? (Score:4, Informative)

      by camperdave ( 969942 ) on Friday October 22, 2010 @09:53AM (#33984752) Journal
      It's more of a spring loaded type of effect. The "correlated" magnetic field, instead of being completely attractive, or completely repulsive, is repulsive up to a certain distance, at which point it becomes attractive. So to arm the toy, you press the magnets together until they reach the attractive distance. This holds them together. To "explode" the toy, you separate the magnets (either by physical means, or by another magnet that cancels the attractive field), and the repulsive fields cause the parts to "explode".

      Imagine a magnetic bowl with the rim being the north pole, and the bottom being the south. Now, imagine lowering the north end of a bar magnet down into the center of the bowl. At first, it will be repulsed by the north field along the rim of the bowl. However, once the end of the bar magnet is lower than the rim of the bowl, the field will force the bar magnet down, and it will be attracted to the bottom of the bowl. At this point, an upward blow large enough to knock the bar magnet loose, and past the lip of the bowl, will cause it to enter the repulsive area of the field, and it will "explode".
      • Unless it explodes it is neither fun nor scientific.

        Mythbusters taught me that.

        • by dwye ( 1127395 )

          Unless it explodes it is neither fun nor scientific.

          Mythbusters taught me that.

          Unless it explodes, it is not fun for the numbers of viewers necessary to charge for enough for their commercials to pay for the show. There is a reason that the Discovery Channels have Shark Week, and do not have Physics PhD Dissertations Defense Week.

  • "The applications appear limitless and include a diverse array of fields: from pick-proof locks and easy on/off snowboard bindings to frictionless gears and robots that can scale walls without touching them."

    These programmable magnest will be great for making robots that clean windows and do repairs in highly-dangerous altitudes and situations. Plus, we can finally build a suit with magnets in it to let us climb like Spider-Man!
  • by Twinbee ( 767046 ) on Friday October 22, 2010 @09:40AM (#33984676) Homepage
    A decade or so back, I created something called "Super Magnet", and the whole idea was to create a system of atoms/magnets with completely customizable forces - a bit like an infinitely extendable version of what Nature does.

    Yes, I know this is in software, but the results can be pretty cool: [] [] []

    Bear in mind these animations are about 10 years old - modern hardware and algorithms would use many more magnets (though creativity counts for quite a bit too).
    • by DrSkwid ( 118965 )

      I like those, nice work. I wouldn't be so quick to downplay the quality :)

      • by Twinbee ( 767046 )
        Thanks! Always wanted to make a program out of it with a full GUI - be pretty complex though. There are other programs out there, but the math you can use on each 'atom' isn't as flexible as far as I know.
  • by tchdab1 ( 164848 ) on Friday October 22, 2010 @09:41AM (#33984688) Homepage

    Having objects, linear or otherwise, with a differing array of N/S, or plusses and minusses, that can attract or repel allows one to create objects that can interact in ways similar to proteins that fold - objects will be able to configure or reconfigure in very interesting ways.
    And we can see it in our space, without microscopes, and play with them.

    • Re: (Score:3, Insightful)

      by EdZ ( 755139 )
      And more importantly, use them to create self-assembling flat packed furniture. No more will people be confused by blindingly simply diagrammatic instructions in their attempts to assemble a shelf!
  • Critical analysis (Score:3, Insightful)

    by Aphoxema ( 1088507 ) on Friday October 22, 2010 @09:50AM (#33984738) Homepage Journal

    Impressive, but how do the modified magnets handle the constant stress of other magnetic fields? Magnets naturally have a general north/south pole because that's the tendency of magnetism. Aren't these magnets likely to "wear off" sooner? Used as gears, wouldn't the exertion of magnetic-kinetic force tear up the "programmed" array of magnetic fields? As gears I'm skeptical they could even be reliable without being staggeringly large. You'd never have to worry about stripped teeth but the weight of the gears is an important factor in energy transference.

    • Re: (Score:3, Interesting)

      by Anonymous Coward

      The concept that wearing off or charging of magnets isn't a correct concept. Unless a magnet is driven past a certian energy level it simply remains. The problem of AlNiCo magnets and similar early on was that they were not of a stable crystal design. They were pretty stable but not completely. The NiB magnets are extremely stable.

      I really appreciate a good question person. Good science is so rare today. We see on /. so many people who chose to heckle rather than to see. I have handled and seen in pe

      • The concept that wearing off or charging of magnets isn't a correct concept. Unless a magnet is driven past a certian energy level it simply remains. The problem of AlNiCo magnets and similar early on was that they were not of a stable crystal design. They were pretty stable but not completely. The NiB magnets are extremely stable.

        I really appreciate a good question person. Good science is so rare today. We see on /. so many people who chose to heckle rather than to see. I have handled and seen in person the CMR demos. Their stuff works. The fundamental understanding here is that a magnetic field is (Shockingly) a magnetic field. Their lead guy noticed that magnetic fields worked exactly like EM Fields from RF. I know it is obvious once said but the discovery is that an EM Field (Electromagnetic Field) is well an EM Field. This allows all of the mix and match you see in standard RF stuff. The principal difference here is that a magnetic field operates like DC rather than RF as AC. Both the same otherwise.

        One demo device they showed me (No disclosure of details because I am under NDA) would slide to attract just as if it were a standard magnet and then it would break away just upon being pushed past the lock point. Think of this one. Ponder it for a while. You mean I could have a motor pole that attracted in just like normal and then actually got repelled away as soon as it passed without any added energy? (no coils or electricity????) Thought you might like to think a long time on this one. This is much more of a discovery set than you might think. No CMR isn't publically proposing to use it for this. Just study on this for a while.

        I appreciate your comments, I was in the belief that magnets in general could be very strong yet their fields were somewhat malleable to the stress of ferrous metals and other magnets.

        In that case, I'm excited about the applications of these modified magnets and hope to see incredible uses for them. Magnetism is a natural force that is used often but poorly understood and it seems little imagination was put into them until this.

        Few new ideas are genuinely patentable anymore... maybe this one is.

      • i assumed there was electricity or coils to change the poles of the magnets according to the 'code' of the cdma signal.

      • by ccool ( 628215 )
        Just to point out that most likely, these magnets will probably be less tolerant to high temperature. If you look at the B/H curve of Neo Magnets, when they are under the influence of strong magnetic field, their demagnetization temperature point gets lower.
      • by Tsaot ( 859424 )

        One demo device they showed me (No disclosure of details because I am under NDA) would slide to attract just as if it were a standard magnet and then it would break away just upon being pushed past the lock point. Think of this one. Ponder it for a while. You mean I could have a motor pole that attracted in just like normal and then actually got repelled away as soon as it passed without any added energy? (no coils or electricity????) Thought you might like to think a long time on this one. This is much more of a discovery set than you might think. No CMR isn't publically proposing to use it for this. Just study on this for a while.

        So they created a magnetic spring that will pull as well as push. I can see how that would be an improvement over metal springs that will break over time, but I can see a whole slew of other problems arising from the need to properly shield the darn things to keep particulates from sticking and creating friction.

      • by cynyr ( 703126 )

        did you just propose a perpetual motion machine? i mean in a vacuum, with magnetic bearings of course.

  • How small can you make these thingys and how fast can you make them flip?

  • Yawn. (Score:5, Funny)

    by lxs ( 131946 ) on Friday October 22, 2010 @09:51AM (#33984744)

    Wake me up when they invent magnets with east and west poles.

  • Magnetic gears? (Score:5, Informative)

    by reg106 ( 256893 ) on Friday October 22, 2010 @09:55AM (#33984770)
    The "frictionless" magnetic gear shown will still have friction in the bearing. The magnetic "teeth" will introduce a huge amount of backlash into the gear system. And you would run into problems if you tried to stack gears beside each other in a gearbox. The high pull-off force/low twist-and-pull force application is neat though. One limitation is that rare earth magnets tend to be brittle, and make a mess when they break.

    To be clear though, magnets have been made with multiple poles for a long time, for example those flexible fridge magnets will often have alternating poles across their surface. Also, the pull off application is in many ways similar to the "switchable magnetic bases" []. In these devices, the orientation of the magnetic is changed to force the field lines to go through the surface underneath, or to be contained within the base. The innovation in the present work is the use of coding theory to design the patterns.
    • They won't have backlash but they will have a certain amount of compliance. High speed low torque situation would be perfect for magnetic gears but traction situations? not so much. I think dozens of people have had the idea of magnetic gears - I know I did. Isn't it a children's toy already?

      I hope this isn't worthy of a patent b/c anyone who has seen a Halbach array will immediately appreciate patterns of poles can generate interesting fields. Halbach arrays Manufacturing of the magnets is non-trivi

    • by Timmmm ( 636430 )

      The huge problem with their magnetic gears is that above a certain torque they will lose all grip. It's the same with stepper motors.

      Cool as this is, what they are basically doing is embedding a set of small magnets into one piece of magnet. For example, the same "frictionless magnetic gear" could be easily created by sticking a lot of alternating N/S magnets on the outside of some wheels. It's pretty much exactly the same thing.

      Still cool though.

    • by mark-t ( 151149 )
      You are correct, magnets with multiple poles have been around for a long time. What may be new here, however, is the ability to do have multiple poles on NdFeB magnets, which traditionally, by my understanding, have only ever been able to be magnetized in a single direction.
    • by cynyr ( 703126 ) [] already uses a "magnetic gear" more of a magnetic coupler, but same idea...

  • by Tacvek ( 948259 ) on Friday October 22, 2010 @10:00AM (#33984808) Journal

    The main pattern shown in the video is stronger than standard NIB magnets at close range. But die out quickly with distance. That makes them much safer to handle. The strongest NIB magnets could seriously injure you.

    I'm curious though about how the pattern used affects how they attract ferrous objects. My hope would be that it has a very similar effect with ferrous objects as with the corresponding magnet, namely that it has greater attraction at short range, but dies out quickly with distance. That also seems logical based on my understanding of induced magnetic dipoles, but I'm no magnetism expert. If so, this also helps to mitigate the other main danger of powerful magnets. (Flying paperclips, etc)

    The pattern they show also has minimal net force if one of the magnets is rotated out of alignment, and provides relatively small resistance to such rotation. That has lots of obvious uses for quick- connect quick-disconnect cables, especially those that need to need to withstand high normal forces, but not rotational forces. I'm not clear how the magnets they show handle shearing forces, but either way would have uses for various connectors.

    • Its a halbach array thats been set to be unidirectional. not exactly rocket science but interesting.

  • I believe indeed he was - about 50 years earlier.
    • by Thud457 ( 234763 )
      I can't decide between funny and troll, and there's no mod for kook, so no points for you!
      • Re: (Score:1, Interesting)

        by Anonymous Coward

        Maybe you should have studied this before opening your mouth by just citing a DAMNED WIKIPEDIA ARTICLE. I wish I could mod you as "moron". The link below contains further reading related to various other organizations who have reviewed and sponsored his projects, incl. GE who appears to have placed his research within their top 100 candidates for projects being worthwhile their time. Do you often get yourself into awkward situations after saying stupid things about topics you have no idea about?


  • What the heck was that green plastic that showed the fields/domains?


  • I'm picturing a train with the 'track' being rails of these magnetic gears, and the underside of the train itself being likewise. It floats above the track, and to cause it to move, you turn the gears on the rails. Seems like not requiring the propulsion on the train itself would make it considerably lighter, would it not?

  • I sincerely enjoy reading about new technologies and techniques as presented by the free-energy charlatans.
    Good entertainment and exercise.

    Run your car on water!
    Generate free electricity; get off the grid!

    • by geekoid ( 135745 )

      Ironically both things you list are possbile.

      The car oner isn't practical, and the 'off the grid' requires a certain amount of space to use. But they are possible.

      • I understand that people doing those ads are selling things that aren't really practical. I also understand for all internets and porpoises, it's a scam.

        I don't recommend any of them.

  • two interacting magnets still have energy lost and converted to heat.

    all frictions are electromagnetic on microscopic level anyway.

  • I've watched the video of "exploding" toys [].
    Quite often, if you look closely, you will see a strange glow on one side when magnets jumps. The glow is slightly purple and lasts something like 0.3s .
    Does anyone know what's happening ? Where does this light comes from ?
  • Owing to their slowness to respond to what ought to be very straightforward queries, I find myself suspecting that they haven't invented everything that they claim.

Exceptions prove the rule, and wreck the budget. -- Miller