Storing Cookies (See : http://ec.europa.eu/ipg/basics/legal/cookies/index_en.htm ) help us to bring you our services at overunity.com . If you use this website and our services you declare yourself okay with using cookies .More Infos here:
https://overunity.com/5553/privacy-policy/
If you do not agree with storing cookies, please LEAVE this website now. From the 25th of May 2018, every existing user has to accept the GDPR agreement at first login. If a user is unwilling to accept the GDPR, he should email us and request to erase his account. Many thanks for your understanding

User Menu

Custom Search

Author Topic: This magnet motor idea should be easy to build and test  (Read 6046 times)

Low-Q

  • Hero Member
  • *****
  • Posts: 2847
This magnet motor idea should be easy to build and test
« on: November 23, 2018, 06:57:17 PM »
A while ago I did a test with a rod controlled rotormagnet, and posted a video about how and why magnet motors cannot work. As a control rod, I used a short one that was acivated very close to the magnet, which resulted in a magnet motor demonstration that did not work (As already suspected). Short distance influence might increase counter torque unnecessarily much, so I guess a longer control rod further from the rotor might reduce counter torque. I guess not, but need to test in this particular motor.


Now, I want to print out some parts, and build a new motor that is based on this principle, but instead of using a short control rod, I want to use a long one that is put through a stationary hole far away from the rotor.


What this control rod is all about, is shown in this video as a white rod that is connected to a rotormagnet which is allowed to turn around inside the rotor: https://youtu.be/7ojxtlM9D04


I suspect that the outcome is negative, but I need to be sure - mostly to learn even more in detail how magnetism works.
Look at the video, and comment your thoughts or questions if anything is unclear.


Vidar

MagnaProp

  • Sr. Member
  • ****
  • Posts: 431
Re: This magnet motor idea should be easy to build and test
« Reply #1 on: November 24, 2018, 09:46:11 AM »
Hi. I like the idea but don't think it can power my spaceships.

Green arrow looks like it's the point of most attraction, so it won't want to move CCW anymore.

The orange arrow looks like a point of resistance. The blue part of the rotor and stator won't want to get any closer than that, preventing the rotor from moving CCW anymore.

Low-Q

  • Hero Member
  • *****
  • Posts: 2847
Re: This magnet motor idea should be easy to build and test
« Reply #2 on: November 24, 2018, 02:11:30 PM »
Hi. I like the idea but don't think it can power my spaceships.

Green arrow looks like it's the point of most attraction, so it won't want to move CCW anymore.

The orange arrow looks like a point of resistance. The blue part of the rotor and stator won't want to get any closer than that, preventing the rotor from moving CCW anymore.
Interesting. What I found, is that the magnetic field must be parallell (or in the vicinity of parallell) to the field of another magnet in order to achieve attraction or repulsion. What I mean is, if you have two very long magnets, lets say 1 meter by 1x1cm, that is polarized through thickness, and align these magnets 90° on eachother like a cross, and put them together, you will have an impact area that is 1x1cm^2, but the attraction or repulsion force is almost not there. However, if you put two 1x1x1cm cube magnets next to eachother, the same impact area, they attract or repel very well. that is because all the magnetic lines are parallell to eachother.


As the rotor magnet approach 90° rotation, the field around the rotor magnet is 90° on the field from the stator magnet. So the forces between those fields are weak. However, at 0°, right at the polarity swap in the stator magnet, the magnetic lines are parallell to the rotor magnet, and have great influence.


I can agree with you, that the rotor magnet could stop there, and not go further, but rather go further than backwards. Not 100% sure if the torque between 45° prior to and after the initial point (90° in total. see picture) builds up enough momentum to overcome the equilibrium as you pointed out, and enough to pushi it into the next torque phase


Vidar.




Low-Q

  • Hero Member
  • *****
  • Posts: 2847
Re: This magnet motor idea should be easy to build and test
« Reply #3 on: November 26, 2018, 07:56:25 AM »
I have decided to build this, but not using a rod to controll the magnets orientation.
Like a wrench on wheel bolts, the rod will cause countertorque to the wheel, because the magnet want to turn the same way as the whole wheel. So I want to make a system that does not do this.
I will use slides that runs on parallell tracks which can move i both X and Y axis. When fasten on the magnet, the sledge will follow the magnet around while keeping the magnetic orientation correct.
This way, the control does not provide torque around the magnets own axis. I think.
The stator magnet will "feel" a torque in the opposite direction no matter where the rotor magnet is, so there must be a reaction force that push the rotor magnet around too.
That is what the simulations shows.


Vidar.

MagnaProp

  • Sr. Member
  • ****
  • Posts: 431
Re: This magnet motor idea should be easy to build and test
« Reply #4 on: November 26, 2018, 09:29:28 AM »
Not sure I fully understand the cross analogy. If the end are meters apart but the two can still come together at the center, it sounds like that might be due to the distance instead of flux not being parallel.

I'm glad you are building your design. There is much to be learned about magnetism that I don't think we yet know.

Low-Q

  • Hero Member
  • *****
  • Posts: 2847
Re: This magnet motor idea should be easy to build and test
« Reply #5 on: November 26, 2018, 10:09:56 AM »
Not sure I fully understand the cross analogy. If the end are meters apart but the two can still come together at the center, it sounds like that might be due to the distance instead of flux not being parallel.

I'm glad you are building your design. There is much to be learned about magnetism that I don't think we yet know.
What I mean, is the same system that controls the print head on a 3D printer. See attached picture.
This mechanism has two parallell rods in the X axis and the Y axis. The print head is slinding along these rods in any possible directions in the XY plane, but keeps the orientation of the print head fixed.
If I try to turn the head, nothing happens. The head does not move in any direction. However, if I had a long rod, like I first suggested, the print head would move in the direction I want to push.


This means I apply "countertorque" in the center of the magnet, and not outside it. What happens to a wheel if tou apply force in the very center at a hub? Absolutely nothing. You must apply force off center to make it spin, and that is exactly what I don't want to.


The rod is therfor causing countertorque in the magnet, just like a socket wrench cause a wheel to turn when you loosen or tighten the wheel bolts.
I must find another way to lock the orientation of that magnet. A system that does not push the magnet in the wrong direction. Torque exist in the stator magnet all the time, I just need the rotor to to "feel" the same way.
For example, if you use a socket wrench, and point the shaft towards center of the wheel, and push on the wrench shaft at the same location as the wheel hub, you can use as much force you want on the wrench without causing the wheel to turn. This method must be adapted in a way that can follow the magnet, and still not cause countertorque.
I think (hope) that the method described above and in the picture do exactly this.


Vidar

Low-Q

  • Hero Member
  • *****
  • Posts: 2847
Re: This magnet motor idea should be easy to build and test
« Reply #6 on: November 27, 2018, 09:49:03 PM »
I realized that torque measurements/simulations is useless. With reference to the first image, the rotor magnet provide torque mainly because itself want to turn around its own axis. This will in turn provide torque to the whole rotor.
However, when that magnet is fixed in one orientation, this torque is gone., but there is one-way torque in the stator (if that could spin freely). So I bumped into a misinterpreting there.
So instead, I calculated forces in X and Y axis for every 7.5 degree rotation, used Cos and Sin calculations to see what torque I got left. Yes, lots of torque, but the positive torque between 330 and 30 degrees, and between 150 and 210 degrees, is zeroed out by the negative torque between 30 and 150 degrees and between 210 and 330 degrees. So the total torque ends up in zero.


So I need to wrap my head around again. However, no bad feelings. Good to learn how magnetic forces behave, and avoid those mistakes again. Plenty of ideas left that I can start working on.


Vidar

MagnaProp

  • Sr. Member
  • ****
  • Posts: 431
Re: This magnet motor idea should be easy to build and test
« Reply #7 on: December 01, 2018, 01:31:52 PM »
Good info and good conclusions. Thanks for the sharing the info.

With each test, we get that much closer to our end goal so keep up the great work.

Low-Q

  • Hero Member
  • *****
  • Posts: 2847
Re: This magnet motor idea should be easy to build and test
« Reply #8 on: December 02, 2018, 12:02:57 AM »
Good info and good conclusions. Thanks for the sharing the info.

With each test, we get that much closer to our end goal so keep up the great work.
Thanks! I'm working on it even if I feel that the learning curve starts to flatten out, LOL  :D


Vidar