easiest magnetic pendulum

[dxer_87]

Pendulum works by gravitational energy only by half of each cycle. If you want to make an eternal pendulum first thing is to compense this amount of energy giving the right mechanical force at the right time. This could be done by magnets (magnetic potential energy) moved in synchronised way.

Simply image. Should work properly with right dimensions and the side magnets must be stable (not mentioned in the picture). The magnetic field must work on the whole half of the movement to cover gravitational loses on the second half. (when arm go upward).

Enjoy & try!

[TinselKoala]

Sounds easy enough, doesn't it? I'll be looking forward to seeing _your_ build of the design.  You can get magnets of about any shape and polarization from K&J Magnetics.  http://www.kjmagnetics.com/
My favorite source for non-magnetic bearings, Small Parts Company, seems to have been absorbed.. and ruined.. by Amazon. So I don't  know a good source for them any more.

But if you want to see something that actually works (but isn't OU, only it is just very efficient, running only on room light or diffuse daylight) you can take a look at this magnetic pendulum:

http://www.youtube.com/watch?v=0dMPQs5vpek

[dxer_87]

Yes, the reasoning is ok. Everything depends on the simulating it. Because I will probably build 50 different models, and none of them will be compensed enough, simply because of the details. But the theory behind it gives you in equation how strong magnet must be for its weight - this will be a factor in such system. May be I could make right equations for these if i have mind to do so.

In the picture I didn't show the limiter of movement, made of tin, but it may be necessary if the magnet may contact in the beginning.

I am a poor constructor, I am better in theory which I learn by constructing <looking greedy at hdd>

We have good shops with magnets already in Poland, but the rest is to be equiped (for motor constructors like cords pwm controllers and so forth)

[shylo]

Hi dxer, I already tried that, the center magnet will find its' resting spot.
TK , Very cool demo, did you ever add more to complete a circumference?
artv

[TinselKoala]

Hi dxer, I already tried that, the center magnet will find its' resting spot.
TK , Very cool demo, did you ever add more to complete a circumference?
artv

Thx...no I haven't made a rotor-motor out of it, if that's what you mean, but the pulsemotor-master Lidmotor has done so:

http://www.youtube.com/watch?v=Kij6dtkhhbE

and I'll probably make one soon, just for completeness sake, but I have to make the coil bobbins first and for me, that's a totally manual process, I have no 3d printer.