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control metallic ball coordinates by magnet

control metallic ball coordinates by magnet

control metallic ball coordinates by magnet


I have zero knowledge in the electromagnetic engineering field, and I would like to know if you can help me in the following question :

Is there a device or a method that allows us to control the position of a small metallic ball ?
For example, the ball initial position is at x=0 y=0 z=0. I would like to control it with a device , and place it in x=1 y=1 z=0 (and keep it fixed in place).

Is there some reference of such work that I can look into or some principles that are in that direction?

Thank you .

RE: control metallic ball coordinates by magnet

Toy magnetically-suspended globes reportedly employ a closed loop, actively controlled magnetic suspension. If they have batteries or an AC adapter, then that's why.

Suspended Globe Image Search (many examples)


RE: control metallic ball coordinates by magnet

I have one of those globes.

There are permanent magnets top and bottom (in the ball or the stand, I don't know), so the ball will not roll away when the active suspension fails. Mine is AC powered.

To get it started, you have to plug it in, then lift the ball carefully toward the suspended position.
As you get within a mm or two of the right position, you can feel the control system start to take over.
Then you gently release the ball, and it stays suspended. Actually, it either snaps up to the top or the bottom for the first hundred times, until you get a feel for it.

If you didn't already know, magnetic attraction is highly nonlinear, so the control system has to work hard to do its job. ... and that's only in one axis, and its working range is pretty small.

As noted, it should be easy to roll a passive but magnetic ball on a thin nonmagnetic plate with an XY translator hidden below, using magnets on the translator carriage, with current technology, but your goal seems more ambitious, and farther away. Perhaps you have time to learn about it before it happens.

Mike Halloran
Pembroke Pines, FL, USA

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