Levitating a metal ball

  • #1
Niall Hannon
Hi guys,
I am trying to produce a desktop feature for a client which consists of a 3d printed cube with a metal ball at its center. I can suspend the ball in the center of the cube using a support or piece of rod, but I would really like to try and make it levitate using an electromagnet. I would like it to be suspended in a similar fashion to the Levitron method, without any magnets above the sphere.
I have done some research into the area but cannot find the specific information I am looking for, i.e:
1: Can it be done with a metal ball bearing or does it need to be a magnet to work properly? And if so, would a spherical magnet work?
2: Can you guys recommend any links to suitable electromagnets that I could purchase?

Any help would be greatly appreciated,
Thanks!
Niall
 

Answers and Replies

  • #2
phinds
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I think you would need a (non-existent) magnetic monopole. A spherical magnet would do you no good since it would just rotate and slam into the fixed magnet. Even the Levitron only stay up as long as it rotates (it's unstable otherwise, as your would be all of the time). What I'm saying is no, it can't be done with a magnet and a ball bearing.
 
  • #3
rcgldr
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I'm wondering if it would be possible to get a small foil covered foam ball to hover in a charged field powered by a hidden battery.
 
  • #4
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I'm wondering if it would be possible to get a small foil covered foam ball to hover in a charged field powered by a hidden battery.
Doesn't matter if it is hidden or not,
A battery has two terminals and won't do anything useful unless both of them are part of a circuit.
 
  • #5
rcgldr
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Doesn't matter if it is hidden or not,
A battery has two terminals and won't do anything useful unless both of them are part of a circuit.
I meant using the battery as a power source to drive something like a mini Van Der Graaf generator, assuming it would be possible to mask the noise.
 
  • #6
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Maybe the easiest way to levitate is by a steady airflow from below, like they do with ping pong balls.
 
  • #7
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A spherical magnet would do you no good since it would just rotate and slam into the fixed magnet.
That would of course happen with a single fixed magnet. But how about several electromagnets with a suitable control to adapt to the rotation?
 
  • #8
sophiecentaur
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It is perfectly possible to arrange for a conducting metal ball to be suspended over an arrangement of 'electromagnets', driven by AC. Maglev trains use this principle. Unfortunately, the system requires complicated electronic circuitry and a controller system.
Also, you may have seen levitation of a superconducting object over a magnet. Problem is that you would need, at least, a constant supply of liquid nitrogen to keep it levitated!!
 
  • #9
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You would probably end up with a liquid ball as well, as inducing constant eddy currents to keep it levitated will cause it to heat.
 
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  • #10
Niall Hannon
Thanks for all the feedback guys, it helped clear up a lot of my grey areas. I am trying to keep this piece as simple as possible so complicated control systems and liquid nitrogen are out of the question, as fun as they would be! I am leaning towards using a spinning disc magnet fixed inside a table tennis ball, this would hopefully satisfy my levitation and magnet stability needs!
Any other ideas or suggestions are more than welcome!
 
  • #12
You would need two inductor coils (one inside the other) and run separate ac currents through each one. Then adjust the phase of the frequencies so that the field is flowing towards the center of the coils. Then you can levitate a non-magnetized aluminum sphere on it.
 
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  • #14
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It is perfectly possible to arrange for a conducting metal ball to be suspended over an arrangement of 'electromagnets', driven by AC. Maglev trains use this principle. Unfortunately, the system requires complicated electronic circuitry and a controller system.
Also, you may have seen levitation of a superconducting object over a magnet. Problem is that you would need, at least, a constant supply of liquid nitrogen to keep it levitated!!
Would it be possible to use this levitation system in reverse though (with the magnet floating and the superconductor as the base) with an electrical cooling system to maintain the low temperatures needed for the superconductor? Or would it be impossible to achieve such low temperatures? Can anyone advise on the temperature requirements for these materials to repel magnets?

I have experimented with levitating a small magnet between two bismuth plates, as bismuth exhibits some diamagnetic properties at room temperature. You need a magnet above to give some lift, and then the magnet floats between the two plates. It's not a spectacular display; the plates are 20mm thick, the gap circa 4mm and the magnet inside 2mm thick. but it does float.

The best bet is likely to be an electromagnet above the ball, which is switched on and off by a control system which measures & controls the height of the ball. But this won't achieve the base-only design you're after.
 
  • #15
DrClaude
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This is an old thread, but since it is being revived, I will add my 2 cents.

I am dismayed by all those who said it is not possible. Such things already exist. Check out for instance:
https://eu.flyte.se/pages/story
 
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