Magnetic levitation with permanent magnets

  • #1
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Main Question or Discussion Point

so i am literally one step away from producing a floating skateboard powered by permanent magnets, so here's what i wanted to check, to make sure I haven't missed anything obvious

vertical lift achieved by using vertical repelling fields
rotational motion is controlled by counterbalancing the magnets desire to flip over and attract
Lateral motion controlled by radial magnets
essentially the magnets cant move down, cant flip over and cant move sideways or backwards or forwards, thus leaving the magnet array stationary and suspended.
 

Answers and Replies

  • #2
sophiecentaur
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to make sure I haven't missed anything obvious
You have missed the other degrees of freedom. Try the same thing on a glass plate, at various heights above the plane of the ring of magnets. Try it without restraining the test magnet's orientation. A hover board hovers. Any magnet will repel upwards is you stop it flipping.
 
  • #3
Vanadium 50
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so i am literally one step away from producing a floating skateboard powered by permanent magnets
And you'll be one step away forever, I'm afraid. I know you don't believe in Earnshaw's theorem, but it's still a theorem.
 
  • #5
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You have missed the other degrees of freedom. Try the same thing on a glass plate, at various heights above the plane of the ring of magnets. Try it without restraining the test magnet's orientation. A hover board hovers. Any magnet will repel upwards is you stop it flipping.
thats what the one step away is, getting quotes to have the magnets needed engineered, the requirements are proving costly
 
  • #6
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  • #7
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And you'll be one step away forever, I'm afraid. I know you don't believe in Earnshaw's theorem, but it's still a theorem.
if and only if this last part doesnt work, with the dimensions it requires to work, then i will give up and move onto electromagnets :)
 
  • #8
berkeman
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yeah ive seen that, but what i figured, especially with magnets is, that if you purposely introduce newtons third law into the equation, then it lets you approach the problem from a whole new angle
One of the most important lessons I've learned in my very creative and productive engineering career is to look for "non-existence proofs" that can help to keep me from going down an unproductive rabbit hole for way too long in trying to invent something or solve a problem.

I guess a part of that is having enough of a technical background to understand the counterarguments and non-existence proofs. What is your technical background? Do you understand the calculus in the link that I posted? One of the most important reasons that I have the great patents that I have is because I cut short the paths that I was investigating that I found out early-on had valid non-existence proofs, and concentrated my work on the other possible paths.

And BTW, the whole "hoverboard" thing requires a surface to generate a repelling force against, so unless you plan on coating bikepaths with diamagnetic materials, that will probably not be practical, IMO.

Keep on being creative and working on good stuff, but think about more education and more emphasis on early non-existence proof detection. :smile:
 
  • #9
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And BTW, the whole "hoverboard" thing requires a surface to generate a repelling force against, so unless you plan on coating bikepaths with diamagnetic materials, that will probably not be practical, IMO.
your thinking is a little too literal for me, i would have to be an absolute idiot to think i could make something repel away from the earth, but to have something repel away from a different kind of surface such as a skateboard that can have a means of repulsion attached to it isnt the thinking of an absolute idiot, why coat bike paths when skateboards can quite happily go along them.
 
  • #10
sophiecentaur
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your thinking is a little too literal for me, i would have to be an absolute idiot to think i could make something repel away from the earth, but to have something repel away from a different kind of surface such as a skateboard that can have a means of repulsion attached to it isnt the thinking of an absolute idiot, why coat bike paths when skateboards can quite happily go along them.
So you wold suspend a overboard over a skateboard? To what end
 
  • #11
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So you wold suspend a overboard over a skateboard? To what end
well, for a start once the lift to weight ratio has been solved the board could support somones weight, with the lateral motion being controlled the person could propel themselves forward in the same way as a conventional board is used, and lastly magnetic fields move in a very similar way to water, this would create a feeling of riding on a liquid. but mainly cause it would be fun
 
  • #12
sophiecentaur
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well, for a start once the lift to weight ratio has been solved the board could support somones weight, with the lateral motion being controlled the person could propel themselves forward in the same way as a conventional board is used, and lastly magnetic fields move in a very similar way to water, this would create a feeling of riding on a liquid. but mainly cause it would be fun
Ahh. :smile:
 
  • #13
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Do you have a sketch of the proposed setup?

If your arrangement has only permanent magnets, then your levitating magnet has to be supported in at least one degree of freedom, it has to move constantly, or it has to rotate. Otherwise it cannot be stable. This is a very fundamental theorem and it applies to all possible magnet configurations.
 
  • #14
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Do you have a sketch of the proposed setup?

If your arrangement has only permanent magnets, then your levitating magnet has to be supported in at least one degree of freedom, it has to move constantly, or it has to rotate. Otherwise it cannot be stable. This is a very fundamental theorem and it applies to all possible magnet configurations.
Do you have a sketch of the proposed setup?

If your arrangement has only permanent magnets, then your levitating magnet has to be supported in at least one degree of freedom, it has to move constantly, or it has to rotate. Otherwise it cannot be stable. This is a very fundamental theorem and it applies to all possible magnet configurations.
the only thing i have at the moment are renders of the concept, which i have included in this reply, , as far as the stability of the floating board, i have the vertical lift sorted, i have the rotational aspect sorted and i have the lateral control sorted, as i said in an earlier post, i am talking to companies about getting the final magnets engineered, their height is causing major issues, but all potential problems as far as preventing the magnets from attracting has been taken into account
full board 2.jpg
Full Board 03.jpg
full board.jpg
halbach array to surround Vert Post.jpg
RENDER 1 OF MAGBOARD.jpg
RENDER 2 OF MAGBOARD.jpg
 
  • #15
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Ah, it is supported at both ends.

I would expect that there are easier ways to make a "soft" board, but it looks like an interesting concept.
 
  • #16
sophiecentaur
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Ah, it is supported at both ends.

I would expect that there are easier ways to make a "soft" board, but it looks like an interesting concept.
Spring suspension, comes to mind. I would expect a skateboarder to want a better feel of contact with the ground than a soggy suspension, though. Certainly for tricks.
 
  • #17
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Ah, it is supported at both ends.
So what exactly is levitating?
 
  • #18
berkeman
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I was thinking springs as well.

@Mack7963 -- Beautiful work. You could win an Industrial Design award with that kind of work. I don't think the magnet thing will work out for you, but you have a lot of talent in Industrial Design. :smile:
 
  • #19
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  • #20
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I was thinking springs as well.

@Mack7963 -- Beautiful work. You could win an Industrial Design award with that kind of work. I don't think the magnet thing will work out for you, but you have a lot of talent in Industrial Design. :smile:
i will take that complement about the design and pay for it with thanks, at this stage its no longer about if it will work or not, now its about getting it to that point where my own eyes see the end result, and above all else its been a learning experience, i know more about magnets now than i did 6 years ago, so even IF it fails, i still walk away from this as a winner......just not a rich one :)
 
  • #21
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Spring suspension, comes to mind. I would expect a skateboarder to want a better feel of contact with the ground than a soggy suspension, though. Certainly for tricks.
as would i if this were designed to be a trick board, taking into account the downward forces generated on landing and the weight of the rider, the magnets would never last past one trick, this is primarily a cruising board, the sogginess of t supportive magnetic field will give a feeling of riding on a liquid, which is where skateboarding came from, surfers, after seeing the 13 second bounce the top board did when pushed down and released was incredibly similar to the motion of a liquid, it will take some relearning as far as control, but i suspect that will be minimal.
one interesting thing i did discover is that the magnets i was using in the live vertical support test, on the bottom board were able to repel the top board far enough upwards so the board cleared the 12" bolts that were keeping the top board in place, thats the weight of the board and the magnets all being propelled upward, add to that the bolts that were acting as lateral anchors, were threaded, and there were 4 of them. which does open up the possibility of tricks still being able to be done, except the board doesn't spin in mid air......the rider does.
 
  • #22
berkeman
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will take that complement about the design
Do you have a background in Industrial Design or in Art? Seriously, that is beautiful work. :smile:
 
  • #23
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Do you have a background in Industrial Design or in Art? Seriously, that is beautiful work. :smile:
i dont, i didnt design the trucks by the way, they were the closest thing to what i wanted i could find in the time i had, i have a very basic working knowledge of a lot of 3d software but no real skill in any of them, the top board and the bottom bar are the only things i designed from scratch.
 
  • #24
berkeman
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i dont, i didnt design the trucks by the way, they were the closest thing to what i wanted i could find in the time i had, i have a very basic working knowledge of a lot of 3d software but no real skill in any of them, the top board and the bottom bar are the only things i designed from scratch.
The trucks are not the beauty in that design. Nice work. :smile:
 
  • #25
berkeman
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I wonder if there is a longboard design in your work that you could sell without the magnets part. The transparent board and 2-story deign work so well, and with longboards, you don't have to worry about scratches from tricks. Have you considered making some longboards for general sale without the magnetic floating effect?


EDIT/ADD -- I would probably buy one for my son as a gift (he's a longboarder at 22 y/o)
 

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