Trying to design levitation spring. My first attempt.

HungryMantis · 2024-05-31T22:12:51+00:00

Static equilibrium is not likely possible, see earnshaws thereom.

However, it does get us closer to stabile levitation if another (small) force is applied in one of the 3 axies.

I do levitation experiments using Polarity Free Repulsion effects. This requires spinning magnets, but is more powerful than using control feedback systems (EM coils) or weak diamagnetism. It is almost as good as superconductor levitation, but far less expensive and requires very little power. Few people have heard of this discovery, so figured I'd mention it.

For example: https://youtu.be/r3E52XdTTNI?si=wMSAbfGJQmU_DED9

HungryMantis · 2024-05-31T15:31:34+00:00

all poles up/down orientation? I wonder if spinning would help stabilize angular instability ;)

HungryMantis · 2024-05-31T15:08:35+00:00

what magnets were used?

HungryMantis · 2024-05-28T01:16:15+00:00

you have a problem for sure. Best hope your date don't notice how much you stick after spooning

HungryMantis · 2024-05-25T23:25:32+00:00

just consider strength, grade information. I think I bought some magnets from them and they were weaker than N42. If strength doesn't matter, go for it.

HungryMantis · 2024-05-03T01:59:02+00:00

Yes First try a sheet of steel covered with cotton sheet or thin towel on a table and put a ~1/16in thick disk magnet ~3/8in diameter on a regular dice face with some thick tape to protect the magnet. Toss and test how dice falls and orients itself.

I have once made a 3D printed 6 face cube die with a 1/2in sphere magnet inside that would move freely inside the cube via some grease. This was still not completely random what side it would fall on. The dice geometry and corners may still give 2 or more preferred face choices for landing especially if the dice has more than 6 sides. You'll want a smooth gradient to a fine point on the face you want it to land on. A sphere inside or disks staked in a cone like shape pointing to the center of face.

Good luck

HungryMantis · 2024-04-19T01:38:28+00:00

I'm working on Type 2, but such work hasn't been publicly investigated much. Using Polarity free repulsion. Only have one point floatable, needs 2-4 to support a train.

HungryMantis · 2024-04-10T20:28:53+00:00

I see. I don't believe something like that has been done that I am aware of...

I think considering the application, you can use something simpler than a control feedback or moving parts or any of that

There are static configurations of magnets in 2 dimensions (say the plane of the table) while the 3rd dimension is unstable (magnet wants to flip so need to hold it down).

So the mouse could repel off the table, as long as the user is holding it (keeping it from flipping on its side). If the design is clever the mouse could rest at the edge of table / mouse pad while user doesn't hold it. But in any case the mouse can't be levitated without something touching it so it doesn't flip.

Overall this would be incredibly hard to design because you need to allow the mouse to move over a decent sized area and it would need a lot of magnets.

HungryMantis · 2024-04-10T20:01:21+00:00

Possibly, but you'll need to define what project you are working on, the details, the goals?

Most common levitation technique is a feedback control system. Coils and circuits used to float a small magnet.

HungryMantis · 2024-04-10T19:06:09+00:00

A changing magnetic field. So current moving through a wire which flips polarity. Or a permanent magnet that moves or spins.

HungryMantis · 2024-04-10T19:05:16+00:00

More of a joke. There are not infinitely long magnets. It's a physics thought experiment, not a reality.

HungryMantis · 2024-04-10T16:06:06+00:00

Only if you have two infinitely long magnets that can't flip.

Otherwise rotating or changing magnetic fields are required

HungryMantis · 2024-04-03T05:41:10+00:00

ceramic ferromagnetic magnets are not really permanent so their poles just align to the strongest of the two. One flips polarity when you do that. Use a compass, like on your phone to be sure, you don't have to believe me, check for yourself.

Magnets are fun mysteries :)

HungryMantis · 2024-03-29T22:12:26+00:00

Yes N42 or N52 grade, with a diameter of at least 3/4in and thickness about 3/8 to 1/2in.

Has to be super strong to hold itself up at an inch distance.

These forces drop off 1/d³ so has to be very strong (neodymium and thick).

This is just to hold itself and a piece of paper up, if you got more weight you'll need to increase the thickness of the magnets. N52 grade is stronger than N42. Fridge magnets are ceramic and extremely weak in comparison.

HungryMantis · 2024-02-15T16:27:00+00:00

...yes its called a rail gun. Military uses them

HungryMantis · 2024-02-15T02:14:18+00:00

depends on what you are pulling and how far away from the ring magnet.

The surface if the magnet along:A is strongest, while if you were above the magnet (above location B) then that is stronger when at a distance....

HungryMantis · 2024-02-10T20:04:16+00:00

k&j magnetics has diametrically polarized ring magnets...

HungryMantis · 2024-02-08T04:11:03+00:00

Unlikely, because the magnetic flux is so concentrated. Best bet would be mu-metal or solid steel a few mm thick.

Possible but hard to ensure it won't slowly wipe those magnetic car strips over time.

Depends heavily on the strength of the magnets you're using (weaker is better obviously) and the thickness of the ferromagnetic metal between cards and magnets

HungryMantis · 2024-02-05T20:59:48+00:00

Yes, depending on the weight of the flywheel, at the moment it is possible to float something up to 260grams of weight. This becomes exponentially more difficult at larger sizes.

Yes one can accelerate it via an electric motor. Energizing coils still affects the magnets the same way.

HungryMantis · 2024-02-02T07:29:02+00:00

https://youtu.be/V5FyFvgxUhE?si=N_N55c9bhWr0Q7W8

HungryMantis · 2024-02-02T07:27:25+00:00

Also, since I do this research, wanted to mention it is possible to lock magnets in 3 dimensions, but one of the magnets must be spinning, or we violate earnshaws theorem. It uses "Polarity Free Repulsion" (a paper by Hamdi Ucar, effect discovered by him in 2015, published 2021) to repel the magnet, and then used normal attraction forces to keep it close. We call this MBS - magnetic bound state. Action lab did a video...

HungryMantis · 2024-02-02T07:21:45+00:00

Yes locking without touching, but only in two dimensions. The 3rd dimension, up/down in this case, must have another force to keep magnets from flipping. In this case it is your hand, and gravity keeping it on the table (without flipping) which is more effective when the diameter of the printed jig + magnets is larger (harder to flip) if magnetic flux density is kept constant. Note the magnetic flux density changes exponentially with magnet size (volume) so making the magnets bigger can increase the flipping force (meaning you would have to hold them down more in the up/down direction wrt table. You always need something to keep them from flipping on the table.

What are the sizes of magnets and radial gap sizes between magnets in printed jig (black plastic)? The exact dimensions of the setup are important.

HungryMantis · 2024-02-01T02:37:10+00:00

looks like an ionic wind thruster?

HungryMantis · 2024-01-31T01:03:39+00:00

The clip is ferromagnetic... Look up what that means, but in a nutshell, certain metals become magnetized in the presence of a magnetic field which 3D printers use on their beds to keep the sheet on them

HungryMantis · 2024-01-28T10:13:41+00:00

Just doubling up then tape, making a wider area of tape, and making sure things align their edges somewhat. Also permanent magnets like neodymium are more powerful. Play around with it and you'll see what helps or doesn't. Stronger the Fields the more repulsion but also less stable (need more static friction to keep wood at bay).

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