Programmable Magnets

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.)"

Re:One small step...

[Haedrian]

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.

Super useful

[captainpanic]

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...

Critical analysis

[Aphoxema]

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:Like folding proteins

[EdZ]

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!

Re:One small step...

[HertzaHaeon]

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.

Re:Obligatory:

[blueg3]

Magnetic fields do no work.

Re:One small step...

[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 direction (away from the Earth).