Levitation

[Lasthitlarry]

Seeing all these highly technical posts, I decided we should discuss levitation.

(shoot me if this has been discussed)

The ultimate lazy boy it would be, you just float around on a seat, or just a butt pad

I got the idea from the topic about free energy, how magnetic fields were a property of space, or something like that.

That is the only thing I can think of that woul work for this invention.

Manipulating magnetic fields to change direction, or maybe the earlier prototypes will simply have a big engine for a chair, highly technical and very dangerous.

Don't know, feel free to discuss or flame.

 

[CycloWizard]

Would the chair hover off the ground, or would you hover off the chair? The chair hovering off the ground wouldn't really accomplish anything except it would slide all the way across the room if you shifted your weight. Trying to get yourself to float above the chair really isn't feasible.

Hovercraft vehicles actually exist. Quite a bit of online information is available on their basic design principles. I built a little RC one a while back, but screwed up something pretty fundamental so it never really got airborne.

 

[f95toli]

If you cover the floor of you appartment with magnets and then use a chair which has a superconductor in it you could easily "float around" on the floor.
I am quite sure this could be done, if you use a high-temperature superconductor such as YBCO you can cool it by liquid nitrogen or even by a cryo-cooler; expensive (the superconductor is quite expensive) but possible.


In fact a popular demonstrator of the Meisner effect is to have someone stand on a magnet (the other way around) and then let them levitate over a superconductor, you should be able to find a photo of a sumo-wrestler levitating a couple of cm above the floor if you google it.

 

[Atomicus]

graviton repelling process = levitation?

 

[dkozloski]

There used to be refridgerators that you moved around by hooking up the exhaust side of a vacuum cleaner to the skirt. In fact GM Frigidaire had a basic hovercraft patent in this area.

 

[DrPizza]

IIRC, water is diamagnetic (repelled by magnetic fields)
Theoretically, if you make a strong enough magnet, the force of repulsion will be greater than your weight.
Then again, since you are more than just water...
Anyway,
I'm not going to go anywhere near attempting to figure out any numbers.

An alternate solution is to freeze your body to near absolute zero. Hopefully some of the materials in your body become super-conducting... super conductors are strongly diamagnetic

 

[f95toli]

I found a link to a page with the levitating sumo-wrestler
http://ffden-2.phys.uaf.edu/212_fall2003.web.dir/Rodney_Guritz20Folder/magnetism.htm

DrPizza: I don' think there is much in your body that can become superconding at normal pressure (most substances become superconducting only under extreme preassure; many GPa); whatever small amounts of lead, aluminium and niobium we have in our body are the only exceptions.

Since superconductors are PERFECT (not just strongly) diamagnets (if they are thick enough) it is actually pretty straightforward to calcultate what field you need.

 

[bobsmith1492]

Water can be "levitated" by strong enough magnetic fields. There is a picture in my physics book of a frog floating in mid-air, perfectly comfortable because the force is distributed so evenly it is like floating in water.

 

[imported_jb]

those frog-floating magnets are HUGE tho, aren't they ?
a magnet floor and magnet chair seems more likely. no good way to keep it in one place tho. sneezing could be difficult.
i guess you could have the magnetic floor tiles 'dent' into the floor. but to have that work nicely, you'd have to have the entire floor 'dentable'. with a remote or something. recessed flooring..

 

[novon]

Electromagnetic force at a microscopic level already levitates you.

 

[DrPizza]

Originally posted by: f95toli
I found a link to a page with the levitating sumo-wrestler
http://ffden-2.phys.uaf.edu/212_fall2003.web.dir/Rodney_Guritz20Folder/magnetism.htm

DrPizza: I don' think there is much in your body that can become superconding at normal pressure (most substances become superconducting only under extreme preassure; many GPa); whatever small amounts of lead, aluminium and niobium we have in our body are the only exceptions.

Since superconductors are PERFECT (not just strongly) diamagnets (if they are thick enough) it is actually pretty straightforward to calcultate what field you need.

I actually haven't a clue of what substances become super-conducting at near absolute zero temperatures. The only super-conductors I ever really spent any time working with were some ceramic compounds in the mid 80's at Alfred University.
Yttrium Barium Copper Oxide, IIRC. We had to make the stuff in lab. They were among the first high temperature super-conductors (high temperature meaning liquid nitrogen temperatures, as opposed to liquid Helium)

At the time, there were all sorts of pipe dreams about room temperature super-conductors. As a student at the time, I didn't think there would ever be room temp super-conductors. I also thought that 90% of the applications they proposed were pipe dreams as well. I was wrong. About 95% of the applications were unrealistic. (utility lines made out of super-conductors)

 

[f95toli]

YBCO is actually the superconductor I use in my research. Currently I am mainly interested in the dynamics of YBCO Josephson junctions and SQUIDs, especially how the d-wave symmetry of the wavefunction affects the transport properties.

There are acutally a few "real" applications of high-temperatures superconductors nowadays such as cables. microwave filters and various applications of SQUIDs.
However NbTi (a conventional superconductor which becomes superconducting at around 14K) is still dominating the commercial market; it is used in superconducting magnets used in e.g MRI-machines which means you can find a NbTi magnet in almost every major hospital in the world (I think General Electric is the biggest supplier); they are also used in research NMR and particle accelerators.

Room temperature superconductivity is still a dream, but nowadays you can buy a single-stage cryo-cooler for $3000 which will cool your device down to about 25K without any helium or nitrogen, this means that there are potentially plenty of applications for high-Tc superconductors.

 

[DrPizza]

oh, I didn't mean to imply that there aren't plenty of applications for high temperature super-conductors.. You just had to be there in ('87 was it?) when the first real high temp super-conductor was discovered. Suddenly, there wasn't a prof in sight on campus. They all vanished to the labs. Before long, some of our experiments were in making super-conductors.

But, the vast majority of the predictions I recall from class never materialized, because there are no room temp super-conductors (at least none at normal atmospheric pressures) I don't recall what the highest temp record is, but if I do recall correctly, it was at 300,000 atmospheres of pressure, and still quite cold.

 

[pm]

Lifters use an interesting levitation technique. It's thought that they employ the Biefeld-Brown effect to generate lift.

http://members.iinet.net.au/~pterren/Lifters.htm
http://members.fortunecity.com/jlnaudin/html/lifters.htm

Ebay has some good prices on high voltage supplies.

For more links, some with videos, do a Google on "high voltage lifter".

 

[AbAbber2k]

Originally posted by: bobsmith1492
Water can be "levitated" by strong enough magnetic fields. There is a picture in my physics book of a frog floating in mid-air, perfectly comfortable because the force is distributed so evenly it is like floating in water.

I've seen the video of this experiment. It's very cool, the frog just kind of slowly spins around. And as for the following poster, yes the magnets were huge I believe... course this was like a decade ago that I saw this.