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Electric Motor 2

by mattmoses Sep 1, 2011
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Please, if you would, what do the jumpers do and any info on bi-directionality?

Hi, I'm not quite sure which part you're referring to by "jumpers"... can you elaborate?

As for bi-directionality, the direction can be changed by swapping the order that the phototransistors are connected to the drive circuit. It's been a few years so I don't remember the specifics, but I think (I'm half-speculating here!) that, let's say the optosensors are labeled like this:


Then to reverse direction, you would connect them up like this:


where A,B have been swapped and C,D have been swapped. Practically, this could be done by adding some switches to the circuit, or it could be done in logic if you add some additional gates after the inverters in the existing schematic.

Ta, you the dude, this is going to help my project so mucho.

I should compliment two people, I see, Matthew Moses and Gregory S. Chirikjian, thank you both very much. In case you're curious, my project requires flat, large diameter motors and this design will scale well I think. Another feature I require is that the top an bottom rotors go in opposite directions. Any thoughts on that please? I am new to this but I will try to find your paper. I am curious as to how the magnetic fields, there are several, interact. Very original thinking you both did here!

Found and d/l, John Hopkins University, woohoo!!

Thank you for Note (11) in your paper. ron.

Hey, very nice job you did here. The schematic drawing gets clipped on the page, could you add it to thing files please? And which LED goes where please? TIA, ron.

Hi, so it turns out that the full image is on the site but the viewer clips it. If you open the image in the viewer, and then click the little "expand" button with the four arrows on it, and THEN if you click the "View Original" link, you should be able to see and download the full un-clipped image.

As for which LED goes where... it's been a few years since I looked at this design and I'm actually not sure. It can be figured out by looking at the order in which the little "ports" (the things the LEDs look through) become open as the rotor rotates.

Hey thanks so much, that gave it in hires to. The jumpers are between the ?transistors and labeled JP1 and JP2..

With further study of your drawing it looks like the jumpers are where you connect the coils.

Cool Thing! I've often thought about using this idea (albeit with ordinary, wound coils) to make a motorized bike/skate wheel. Some thoughts:

What about making a second coil plate (wired in parallel), sandwiching the rotor (sans washers) between them, and (directly) using both ends of the magnets?

If I made this, I would use a proper bearing (e.g. a 608 skate-type). Since magnets will likely not be printable before (proper, metal) bearings, I think its utility would outweigh it's "vitamin-ness" :)

Two words: Halbach array ;)

What is all of that grinding noise I hear in those videos? That shouldn't be making much to any sound with a nice set of bearings so I had to ask.

Considering the simplicity of the methods used to make the bearings in this motor, they work quite well.

The rollers are made from chunks of 3mm filament, the cage is free to rattle around, one of the flat rolling surfaces has standard 3D-printed surface finish, and radial alignment is plastic on plastic. It is natural that they make some noise when running at 2000 rpm.

Amazing work!

What is the coil trace spacing and width? Do you think a 0.5mm tip sharpie would be able to draw the traces? I guess worst case, it could be scaled up.

Also, does it work in reverse as a generator? :)

The minimum coil spacing is 0.254mm. The trace width is 0.381mm. The matlab/octave code "flatcoilwind" can be used to create patterns with different geometry. For example the trace width could be increased by reducing the number of turns, but this would also reduce performance of the motor.

It works as a generator, but produces AC current.

In important point I'd like to make with projects like these (proposed "over unity"). I have seen a lot of these projects over the years, both on-line and in person. There are some real nut-jobs out there with a feeble understanding of physics and more belief than they have common sense. I can say with confidence that the majority of these hobbyist (and semi-pro) "over unity" projects are flawed on a number of levels.

Now, that being said, there is also a fevered witch-hunt to burn any heathen who doth extol the heresy of "over-unity" in any way, shape or form and that can hurt the spirit of innovation and honest experimentation.

Why do I care? Well, I too have a project knocking around my shop that aims to m
ake similar claims. Once I get my 3d printer (or use/rent someone else's) I'll be putting to plastic some ideas and maybe it will turn into something. Maybe not.

But here's a couple things I'd like to say to clear the air.

  • Nobody (except nut-jobs) is claiming violation of physical laws.
  • Th
    e vernacular use of the term "over-unity" refers to a state where a device generates more output energy that is required to maintain its operating state.

The reality is that there are more kinds of energy at work in these flywheel magnetic motor designs than just electricity. There is the kineti
c energy of the magnets and the apparatus itself, there is the "kick-start" energy "investment" like a starter charge or even spun by hand, there is of course the magnetic potential of the magnets and often clever circuitry to load-balance, pulse, polarize, time and even boost with capacitors. All
of these elements work together to make the output energy which is electricity. But the "working" energy is more than electricity. That's where the surplus comes from. The basic idea is that with the right design and calibration, you can catalyze the kinetic and magnetic potential of the apparatu
s with an "investment" like electricity to the point where minimal electricity is needed to maintain the ideal running speed. The magnets will generate electricity through induction, and if the design is right and the operating conditions are good, there's a point where the magnets are generating m
ore ELECTRICAL energy than is needed to maintain the rotational speed of the armature.



Remember, there is more energy here than electricity. Just like a nuclear reactor converts radioactive material's potential energy to significant amounts of electrical energy with really no "investment energy" just reaction. The armature has weight from the material and magnets; spinning, there'
s angular momentum. The magnets have magnetic potential. That's energy. Without "more" energy, this system will spin down and come to a stop on it's own. But it will still spin for a while to reach the rest state. The permanent magnets will keep their potential for a reasonable amount of (geologic
) time. :) Add a small bit of extra energy at high speed and you satisfy the inertial resistance and you keep it moving. Depending on the design, there should be a point where the electricity generated by the magnets is greater than the amount needed to maintain the rotational speed of the devic
e. Take the extra off the top and there you go.

In all of this, design is key. Better materials, better magnets, better control circuits, optional cooling, better bearings... it all affects performance. But the bottom line is, there is no "free" energy here. Actually, I thought long and hard a
bout a more appropriate name for such a device and I am going with "Electro-kinetic Reactor." Because that's what is is.

A Reactor.

Anyhow. I hope to have a 3d printer soon and start an open-source project for this. None of us are smarter than all of us and if there is any practical use (or d
ebilitating flaw in theory) the community will be the ones to find it. Everyone is chomping at the bit to patent and profit from this and that puts them under intense scrutiny and pressure from society. This needs to be in everyone's hands and if it's a good idea, it will float to the top. If not
, it will disappear.

Sorry for the rant.

Oh, and awesome motor mattmoses! :)

Ooop and forgot, Andrew, I've seen a design very similar to this before. Even my design is based off the same concept. The one I saw in person and interacted with seemed to work okay, but devices of this size don't give off much power and the technology is hard to scale. This Trojan III claims 12v 4A which is respectable for a lot of small things. (Charge a laptop for example) But in the grand scheme of things, if you want to be "off the grid" you need a LOT more power and the bigger you go, the advantages of this design diminishes.

But like a said, we need an open-source version for us all to play with. I'm on it! ;)

Oh and mattmoses, that is exactly true. The machine will eventually stop. Aside from a mechanical failure like a bearing going out or an electronic component failure, neodymium magnets lose slightly less than 1% of their "flux density" every 100 years of so. That will make the device less efficient and require more electricity to keep going. Eventually, it will drop under "unity" and eventually sputter to a stop.

But I'm okay with that. ^__^

ErikJDurwoodII: That is not what I meant. In a purely magnetic "motor" it is precisely the rapid depletion of the magnet strength that allows the motor to "work". Were the magnets to maintain constant strength, the motor would not work. The slower the depletion of the magnets, the smaller is the power output. The more power output, the faster the depletion of the magnets. The folks that build these magnet motors often wonder why their magnets "degauss" so fast. They are missing the fact that the degaussing is what makes them work!

I see what you meant. In a purely magnetic "motor." I thought you were referring to these electromagnetic/permanent magnet devices. My mistake.

Degaussing is an issue for these devices as well. On the well designed versions, the coils are pulsed in patterns to deliberately oscillate the field and "re-shape" it as it goes but that only goes so far. Higher quality magnets kept cool(er) can go a long way.

Well, I don't believe that the electromagnetic/permanent magnet devices work either. I am extremely skeptical of anything related to "free energy", "over-unity", and so on.

But you are correct that free inquiry and open minds are essential to innovation. Best of luck with your research. :)

As you should be! I would expect no less. I'm not sold on it either, but half the fun is in the try! If anything I can keep it on power, print some blades for it and have a nice brush-less desk fan! ;)

This is physically impossible, unless he has some batteries hidden in there.


Yeah, he doesn't exactly spin around the whole entire thing in the videos...it possible he could be hiding something (like a battery) somewhere... He picks the thing up and moves it in the second video, but it's still possible that there might be something under the table and under the floor that keeps the thing spinning.

It is possible for a purely magnetic motor to operate, but only if the magnets lose strength with each cycle. The motor will not operate unless the magnets weaken over time, and of course once they are depleted the motor stops! I think honest people misinterpret this phenomenon and assume that with "better magnets" the motors would work indefinitely. On the other hand, dishonest fraudsters love free energy nonsense and the only thing they will ever perpetually generate is a perpetual stream of hoaxes.

I find it fascinating that youtubes of free energy bunk get so much more attention than youtubes of legitimate engineering projects. People really want to believe, I guess.

Love the LEGO bushings used as spacers. :)

Nice work Matt!

I always enjoy seeing what happens to the parts I make. It is not very often I get to see what happens with them once they go in the shipping box.

I'll be sure to post a link to the video on our Facebook page.