Why won't this work??

[fritznien]

still can't see it.
is this it?
http://www.lhup.edu/~dsimanek/museum/themes/woodward.jpg
as for why it don't work.quote
This 19th century invention by F. G. Woodward suggests that since there's more weight of ring to the left of the two rollers, it must turn counterclockwise. Even naive students immediately recognize that there's no reason to expect it to turn. Does our center of gravity principle apply? It qualifies as a supposedly gravity-driven wheel. The ring's center of gravity never goes above its own rotation axis. The rollers' centers of gravity never go above their rotation axes either. This curious paperweight will just sit there, unmoving.

[magnetman12003]

still can't see it.
is this it?
http://www.lhup.edu/~dsimanek/museum/themes/woodward.jpg
as for why it don't work.quote
This 19th century invention by F. G. Woodward suggests that since there's more weight of ring to the left of the two rollers, it must turn counterclockwise. Even naive students immediately recognize that there's no reason to expect it to turn. Does our center of gravity principle apply? It qualifies as a supposedly gravity-driven wheel. The ring's center of gravity never goes above its own rotation axis. The rollers' centers of gravity never go above their rotation axes either. This curious paperweight will just sit there, unmoving.

  That's the one!!!    It might work but only if the roller on the top was perfectly in line with the center plane of the hoop.  The hoop has to be heavy and the rollers friction free like modern skate bearings are.  That was made many years ago when roller bearings were not that great.  Any one for trying it out?  All that's needed is a  long 2x4 with roller bolt holes drilled through it. A heavy flat  hoop, two 5/16 inch diameter bolts and skate bearings.  Simple setup. .  Like a SEE-SAW  without the saw part.

http://englishclassperpetualmotion.blogspot.co.uk/2013/03/fg-woodward-machine.html

[MarkE]

Timken got very very rich making high quality roller bearings.  Better bearings won't make this unworkable idea fly.

[Farmhand]

I'm a boilermaker and I have used setups like that to hold the pipe/cylinder work piece so it can be welded.
There are lever forces on the rollers but there is no reason for the cylinder to rotate, none at all. You put a cylinder in a "jig" like
that so you can turn the cylinder while its welded around the circumference. If a weight is added to the far left of the hanging
cylinder then the weight will want to go to the bottom of the cylinder and hold it there. Can't you see that ? Looks obvious to me.
if the rollers are good then the cylinder can be turned with not much effort. There is a use for that.

very easy to test, if you think it should work now in modern times for some reason. 

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