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View Full Version : A magnetic alternative to ice skating?


whyiseveryonestupid!
05-02-2006, 02:15 PM
Had a mad idea and I'm not too good with physics so I'm not sure if it could work or not. The same pole on different magnets will repel each other so what if you had a very large magnet/electromagnet as a floor and had magnets of the same pole as soles on special boots. Then people could enter the room wearing the boots and float/skate on the floor because they would be repelled so wouldn't be able to stand on the floor. Then they could do ice skating/ roller blading moves with very little friction. You could even have body pads made with the same magnets so you couldn't actually fall over and hurt yourself, you'd just float some inches off the ground.

Is this an interesting but expensive idea for a new sport or is there some major flaw I'm missing?

groman
05-02-2006, 02:18 PM
Well diregarding all other problems there's no way to restrict friction in specific directions with such a setup. You wouldn't be able to skate or even keep balance without some sort of an elaborate arrangement of fans and jets.

UncleRojelio
05-02-2006, 02:19 PM
My first thought would be at it would be much, much more difficult. The moment you start to lose your balance, the magentic force would be actively pushing you further off balance, effectively working against you. But, other than that, sounds like fun. Hope you make a fortune with it.

whyiseveryonestupid!
05-02-2006, 02:25 PM
Ah, thought there would be some basic flaw in the idea. I imagined you'd just glide at a reasonable speed to the edge of the floor then have to turn round a glide to the other side but as I said, I'm not too good with physics so thanks for explaining.

Mangetout
05-02-2006, 02:43 PM
Setting up magentic levitation is really tricky Mag_lev trains do it by the use of all sorts of sophisticated control electronics (and superconducting magnets IIRC) that would be too bulky for the skater to carry.

Another reason Mag-Levs work is the rigidity of structure; magnets set up to repel each other are inherently unstable and would prefer to flip over and stick together by attracting poles; if the skater's boot sole repels the floor, the tendency would be for the sole to flip over and attract the floor by its inner surface - given the field strength required to levitate a human, the flipping over action would probably break the ankles of the skater and crush his feet between the floor and the inner surface of the sole.

whyiseveryonestupid!
05-02-2006, 02:52 PM
Hmm, breaking ankles doesn't sound like the best way to start a leisure attraction, it'll have to stay as a nice idea.

some white dude
05-02-2006, 02:58 PM
The same pole on different magnets will repel each other so what if you had a very large magnet/electromagnet as a floor and had magnets of the same pole as soles on special boots.This is the problem. All magnets are dipoles. Even if you cut the magnet in half, you'll just be left with a smaller, weaker dipole. As Mangetout said, the opposite side of the magnetboot would likely be attracted to the floor after a fall.

some white dude
05-02-2006, 02:59 PM
Er, not to beat a dead horse or anything. :smack:

CC
05-02-2006, 03:02 PM
If I understand your set-up correctly, you'd have everyone on the "ice" levitating above the surface, but there'd be no way for them to initiate any forward motion. I visualize a bunch of people with magnets on their shoes, sort of bouncing around on the field, pushing each other around like a bunch of bumper cars. Something's missing.

scr4
05-02-2006, 03:02 PM
Setting up magentic levitation is really tricky Mag_lev trains do it by the use of all sorts of sophisticated control electronics...
That's only true if you use attraction between magnets, like the Transrapid maglev system. The Japanese design uses repulsive force between a superconducting magnet on the train and passive coils on the rail; I believe this requires no control electronics. Repulsion is inherently self-correcting (as magnets get closer, repulsion gets stronger and push them apart).

The issue groman pointed out is the most serious. Skating involves pushing on the ice.

Green Bean
05-02-2006, 03:14 PM
Well, even if the ice skating thing wouldn't work, maybe the technology could be used for other leisure activities. Like what about a waterslide that uses a magnetic force instead of water to reduce friction?

Lightnin'
05-02-2006, 03:37 PM
How about this?

The surface of the floor is studded with lots of small magnets, all pointing the same direction (up). Very strong magnets, of course.

The boots you wear use electromagnets, instead of permanent magnets. A microprocessor turns them on and off, actively, to keep you balanced. They also provide the motive force- they pull you forward by interacting with the floor ahead of you.

Might work better as a Segway-type device. Where's the fun in that, though?

Jake
05-02-2006, 03:49 PM
Possible if you are going around in a circle all the time. But how would you do a figure eight? A figure skater doing an axel? How would he/she get her feet off the ice? Or whatever surface.

jjimm
05-02-2006, 03:54 PM
How about using Lightnin's idea, but covering yourself completely in electromagnets on a body suit, and just throwing yourself around the floor in any orientation, without fear of hurting yourself. I'd pay good money to do that.

whyiseveryonestupid!
05-03-2006, 03:20 PM
Throwing yourself around without risk of getting hurt sounds like fun, wouldn't you have to do it pretty slowly though so you didn't get whiplash or sprain something? Still sounds like a great idea, like a strange version of zero gravity.

Sal Ammoniac
05-03-2006, 03:25 PM
I don't know, to me it sounds like there's potential in this. It wouldn't be skating, but it'd be something equally cool. Maybe a harness hooked to a pulley contraption on the ceiling could keep you from falling, and some form of electric controls could whiz you madly over the surface.

I see cost as being a issue, unfortunately.

Hampshire
05-03-2006, 03:28 PM
The downside I immediately saw was the was no way to steer or push yourself. Rollerskates and iceskates do use friction for you to push, stop, and steer.
Otherwise it would be like putting everyone on fresh ice with bowling shoes, very little friction but no way to get around.

panamajack
05-03-2006, 05:37 PM
The friction part wouldn't be too difficult to overcome. Simply put a plastic (or hard rubber, or what have you) tip on the front of the shoe. It'd be altogether different from skating now, but I think it'd be possible to learn.

The balance issue, however, is probably too much. It'd be too difficult for the average person. I think it'd be better implemented as 'mag-lev bumper cars' or something like that.

scotandrsn
05-03-2006, 05:51 PM
Well, I understand the vision that whyiseveryonestupid! is going for, it's just that it can't be achieved by simply sticking the magnets in proximity to each other and hoping for the best. To create a maglev analog of ice skating, you'd need a more sohpisticated "rink" and special electronics that responded to the skater's movements, perhaps in the skates or in some sort of body suit.

When the skater made the motion an ice skater would to push themselves off, the skates would increase their repulsion in the appropriate direction. A system of alternating polarities such as maglev trains have been known to use could continue the motion,etc.

I recall experiments done in the 1980s using RF to sense the distance between two sensors worn on the body, which might be of use here. I think all the technlogy you'd need is either extant, or more than probably available within the next one or two decades.

Mangetout
05-04-2006, 02:44 AM
How about this?

The surface of the floor is studded with lots of small magnets, all pointing the same direction (up). Very strong magnets, of course.The problem with this part is that when you put a bunch of magnets together, all facing the same way, their magnetic fields interact; I don't think there's any easy way to get a large, flat, uniformly monopolar area using permanent magnets.

The boots you wear use electromagnets, instead of permanent magnets. A microprocessor turns them on and off, actively, to keep you balanced. They also provide the motive force- they pull you forward by interacting with the floor ahead of you.And I suspect this is going to be one of those problems where it simply can't be easily done at human-portable scale; your electromagnets need to be hellish powerful, which means you need a whopping great power source for them, both of which factors add lots of weight to the system, meaning that your magnets need to be even more powerful. Of course, you eventually reach a break-even point where the magnets can be made sufficiently powerful to lift themselves and their power source, but in doing so, you just built a magnet suit (probably)the size and weight of a mag-lev train carriage.