Coupled rotors and "spinning magnetic fields"

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PhysicsProf

Coupled rotors and "spinning magnetic fields" « on: 2013-06-07, 19:13:58 »

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There is something about rotating magnets that is attractive to me

Slider showed how to take a second rotor (4 magnets on a plastic lid) and drive it with a first similar rotor. Great work slider! here as it functions on my bench:

http://www.youtube.com/watch?v=oeACDx6Ne1w&feature=youtu.be

I got the second rotor, magnetic coupling, rotating at about twice the RPM's of the first. Just looking from above and simple counting/timing.

I'm having some trouble getting the laser-tachometer to work on this, with 4 shiny magnets -- any ideas?

I've worked with Faraday motors before. Had some surprises there...

PhysicsProf	Re: Coupled rotors and "spinning magnetic fields" « Reply #1 on: 2013-06-07, 19:35:28 »
Group: Professor Hero Member Posts: 3215	Second vid - interrupting the rotation of the second rotor with a sheet of mu-metal. http://www.youtube.com/watch?v=YWEbe5p1wso&feature=youtu.be

Slider2732

Re: Coupled rotors and "spinning magnetic fields" « Reply #2 on: 2013-06-07, 21:11:18 »

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Here's the tip for RPM measuring...place a small piece of silvered foil on the rotor and measure from above.
Most RPM units have such foil included and its already sticky on one side. It'll work if it's the minimum size needed for measuring. Just need to be dramatically different to the other surface colour for the laser to see it.
It's similar to Berdini wheels etc and will work, because the magnets are on the Y plane as opposed to the X plane.
(Sorry, got Thermat's Last Theorem on the brain today lol).

Will come back to this message shortly, off to view your videos now, but wanted to post before I forgot

I liked the Mu metal experiment. It would be interesting to find out at what point the field is stopped from interacting. Would it be 1%, 49% or somewhere else. Also, would direction of rotor travel affect the point at which the Mu metal stopped the other rotor. Very interesting indeed.
I'm just glad that all arrived safely, envisaged magnets flying around in the box.

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PhysicsProf	Re: Coupled rotors and "spinning magnetic fields" « Reply #3 on: 2013-06-07, 21:29:58 »
Group: Professor Hero Member Posts: 3215	Thanks, Slider! Having lots of fun with this, Slider -- I really think you should consider going into production of "kits"! 3rd vid: http://www.youtube.com/watch?v=VRL3AvQYDfg&feature=youtu.be 22seconds.

Slider2732

Re: Coupled rotors and "spinning magnetic fields" « Reply #4 on: 2013-06-07, 21:38:32 »

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Oh now that was cool...the height difference was quite surprising.
With proper coupling like that, it can be imagined that aircore coils for pickup around the outside of 1 rotor wouldn't impact the function of a lower rotor to the same extent.
For example, placing the Mu metal at the side of the upper rotor may still allow the interaction to occur.
It then would become a Y axis situation, rather than the X axis of the previous video

About the kits, yeah would be a good idea. I've got plenty of everything except the little magnets. 1 of the correct type can be found in dancing flowers, but that would be a weird route to take...though my local Dollar tree would do some smiling shifting a case of them lol

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PhysicsProf	Re: Coupled rotors and "spinning magnetic fields" « Reply #5 on: 2013-06-07, 22:08:50 »
Group: Professor Hero Member Posts: 3215	OK, good ideas. There must be a good supplier for approx 4mm-square neos. Fourth vid -- using a DC PS, measuring input V and I(which varies!) - http://www.youtube.com/watch?v=l9Z55664QWw&feature=youtu.be So driving the two rotors at very roughly 100uW.

TinMan

Re: Coupled rotors and "spinning magnetic fields" « Reply #6 on: 2013-06-08, 02:48:32 »

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I have seen many video's of magnetic coupling drive's,and wondered if the drag would be reflected onto the prime mover. I would think that it would be,as the force would be equal in both directions of the magnetic fields. This is basicly using the magnetic fields like teeth on gear;s,where you can gear it up or down depending on the amount of magnets on each rotor.
Here is one of the video's i found.
http://www.youtube.com/watch?v=fldu5l8_Ips

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PhysicsProf

Re: Coupled rotors and "spinning magnetic fields" « Reply #7 on: 2013-06-08, 14:59:05 »

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Interesting vid, thanks, Tinman.

Expt 5: http://www.youtube.com/watch?v=iusp30ERhvo

I've been moving the mu-metal shield further and further, between the Slider motor and independent rotor. This short vid shows how the coupling between the two persists even with so much shielding between them.

To further understand why coupling with a rotating magnetic field is curious, pls see this video, where coupling is NOT seen: http://www.youtube.com/watch?v=IlUY3snoWI8

So, what is the difference? why do magnetic fields couple in one case and not the other?

Slider2732

Re: Coupled rotors and "spinning magnetic fields" « Reply #8 on: 2013-06-08, 18:39:22 »

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Good to see you on this thread Brad...that video has 261 Dislikes, but i'm sure 260 of them have never tried such couplings.

The drag is only reflected upon the prime mover, if the coupling isn't tuned. It's a lot like the Primary and Secondary of a Tesla tower (and just about the only reason I can think of as to why Tesla got magnet strength named after him

).
Slightly too near = better cogging and easier starting, but a slow down of the powered rotor.
Slightly too far away = rotation coupling may drop out.
There can be a loss, something like 10RPM from 300RPM, but the distant rotor will now be spinning at 300RPMN or 600RPM, as Steve showed.
If the powered rotor is doing 300RPM and the same weight mass distant rotor is doing 600RPM, that doesn't make a lot of sense does it ! Torque would presumably have to be half of the powered rotor, minus natural losses from not being powered - which wouldn't even feature if aircore coils picked off the energy of the spinning rotors.

The Faraday Paradox proves the need to think of magnets as gears. Whichever way they link is just the same as teeth on a cog.
In the video above, the magnet didn't spin when under the other one, same as a cog won't turn if above another.
I believe the lines of force are cone shaped, giving Steve's ability to put the distant rotor on books (enjoyed that vid as i'd never tried it).

Here's my best ever run so far: http://www.youtube.com/watch?v=D9V8BEtqRbg
4 rotors, only 1 powered.
Feasibly, rotor after rotor could link from each other and have collector coils tapping the energy from each!
In such a way, the 261 Dislikes video doesn't strike the mind as impossible for what the guy claims.

Here's a fun thought - consider a large circle, with say a dozen rotors spinning.
What happens if the 12th rotor is placed to interact with the first rotor ?

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PhysicsProf

Re: Coupled rotors and "spinning magnetic fields" « Reply #9 on: 2013-06-08, 21:06:00 »

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Slider:

Quote

"The Faraday Paradox proves the need to think of magnets as gears. Whichever way they link is just the same as teeth on a cog.
In the video above, the magnet didn't spin when under the other one, same as a cog won't turn if above another."

Yes, that fits the data I've seen so far. Still lots to understand here for me.

Your twelfth rotor will certain interact with the other, Mark, and probably keep both from turning (I think) -- following the teeth on a cog model.

The power draw at 0.67 V is about 30 uW for this motor -- which is pretty good!
Now Lasersaber has his Pin down to about 1uW for his motor, which is remarkable... see vid with the 1000uF cap running the motor (and following vids).

PhysicsProf

Re: Coupled rotors and "spinning magnetic fields" « Reply #10 on: 2013-06-08, 21:23:27 »

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Mark, would you care to share how you built the "Slider motor" from the $1 dancing flower parts? I can understand if you'd rather keep that to yourself-- if you're going to build these puppies! I think you'd find some willing buyers if you did...

Also, I'm wondering about a pick-up coil, to feed power back into the system.. any thoughts on that?

Finally, take a look at this - a sweet spot/levitation or magnetic trap using multiple neos:

http://www.youtube.com/watch?v=icpGonZljvA pretty cool

http://www.boreme.com/posting.php?id=35811 so a company turns it horizontal, sells it as a magnetic toy...

Slider2732

Re: Coupled rotors and "spinning magnetic fields" « Reply #11 on: 2013-06-09, 02:18:14 »

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There's nothing to be hidden with the dancing flower type motor

It's just the circuit board, with coil, then put with the semi-levitated rotor.
In a dancing flower, the coil sits on a base and is glued to it. To remove the coil, it's safest and easiest to bend the plastics down either side of it with pliers, such that the glue breaks and the coil can be lifted away. The 'petals' are on a hinge, with a dangling piece of plastic that has some weight and a small neo mounted inside. The neo is pushed each time the coil fires and produces a pendulum type swing to and fro.
All i've done, is to convert each firing to 360 degree rotation, by having the 4 magnets on the rotor.
2 magnets on opposites sides work, but it doesn't always self start.
It's well worth grabbing a couple of them and taking them apart, for the solar panel too.

I think I have to renew my work permit, it was a year not long ago that it came through and I have no idea if it's all still valid...indeed what would constitute work. In light of which, i've not updated my website in quite a while...who knows what the data collectors will use these days. These would make a good addition to the Thortz Energy range though, so will sort it out

For a pick up coil, it has to be air cored. Dancing flower coils seem too weak in that regard and there will be better methods i'm sure. For one thing, those coils are 48 gauge wire or something, current is highly limited.

The way the magnet stuck in the one spot was good in that first video - thoughts were for for a mendocino type bearing assembly. It could race up to mad speeds and be completely stable.
The second video is a classic. I built a version of that after seeing his video a short while ago, using the 5 LED flashlight from (once again) Dollar Tree. The metallic looking mirror plastic has holes that fit the dancing flower magnets perfectly. But it wouldn't do the tricks of his setup as I had it arranged....must return to that one !

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PhysicsProf	Re: Coupled rotors and "spinning magnetic fields" « Reply #12 on: 2013-06-09, 14:18:05 »
Group: Professor Hero Member Posts: 3215	Thanks for that explanation, Slider - great little motor you've got there! Latest motor by Lidmotor uses the DadHav circuit. http://youtu.be/XHGQZucIMl8

Slider2732

Re: Coupled rotors and "spinning magnetic fields" « Reply #13 on: 2013-06-11, 17:01:33 »

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Say, just as a little tidbit of weirdness.

I decided to get some updates done on the website and found that I couldn't log in via the file transfer program.
So logged into the Thortz Energy account at the webhost's website.
Here was what greeted me:
That the Thortz Energy website was Inactive due to Abuse !
'Automatically generated website or malicious script / software was uploaded to thortzenergy.t15.org '

I immediately sent a support ticket and enquired as to what had happened.
They responded quickly with:

2013-06-11 00:10:27
Support
re-activated
was fail of our abuse check software, sorry

Thank you for using our services.

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PhysicsProf	Re: Coupled rotors and "spinning magnetic fields" « Reply #14 on: 2013-06-12, 02:06:50 »
Group: Professor Hero Member Posts: 3215	"Thank you for using our services." That means they could shut down sites whenever they wished, evidently. First NSA spying, next... http://www.youtube.com/watch?v=5hfEBupAeo4&feature=player_embedded

PhysicsProf	Re: Coupled rotors and "spinning magnetic fields" « Reply #15 on: 2013-06-15, 19:16:48 »
Group: Professor Hero Member Posts: 3215	Lidmotor shows coupled magnetic rotors also -- these two at 90 degrees... http://www.youtube.com/watch?v=9bS73BE1oJo&feature=em-uploademail fun stuff.

Slider2732

Re: Coupled rotors and "spinning magnetic fields" « Reply #16 on: 2013-06-19, 18:12:09 »

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Doing some experiments here.
Here's my latest vid, showing 3 rotors all turning, plus a coil based meter being 'wobbled' by the magnetics.
http://www.youtube.com/watch?v=xZYHjniV5VY

What's interesting, is that rotation of the unpowered ones is in the same direction and, that the outer furthest away rotor is spinning at twice the speed of the other two.

A 4th rotor hasn't worked out, because it uses curved magnets and their poles are all messed up. Am looking for any 'real' small magnets now to redo that rotor.

« Last Edit: 2013-06-19, 19:22:32 by Slider2732 »

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PhysicsProf	Re: Coupled rotors and "spinning magnetic fields" « Reply #17 on: 2013-06-20, 05:42:50 »
Group: Professor Hero Member Posts: 3215	Another awesome vid, slider. Thanks.

TinMan

Re: Coupled rotors and "spinning magnetic fields" « Reply #18 on: 2013-06-20, 15:29:10 »

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I'm guessing the third rotor had the same amount of magnets on it?-and I'm sure it has already been stated as such(i must have missed it lol)
I found it quite interesting that the third rotor is spinning at twice the speed,and I'm guessing it must be like jumping a gear every two-if they were gears. A magnetic non contact gearbox-now that's cool-no loss to friction between meshing gears,and no oil needed. Could you place an air core coil near the last rotor,and place an LED as a load across the coil to see if it reflects on the prime mover?-i suspect it will,just like any other gear set would.

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PhysicsProf

Re: Coupled rotors and "spinning magnetic fields" « Reply #19 on: 2013-06-20, 16:02:30 »

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What's wild IMO is that the third rotor spins in the SAME direction as the one nearest to it -- not "gear-like" -- unless somehow this rotor is "geared" to the initial blue rotor, much further away. Strange.

Here's another strange one IMO -- an experiment I came up with, charging up a cap through a Schottky diode by SPINNING a ring magnet over a bpc... enjoy "Faraday's Paradox Revisited" --

http://www.youtube.com/watch?v=I3hXYSKxsX0&feature=youtu.be