"Somsky gears" are an apparently intriguing combination of number theory and geometry: https://www.youtube.com/watch?v=M_BUn4TDns8 WFL On 7/8/15, Fred Lunnon <fred.lunnon@gmail.com> wrote:
Dangerous stuff ... big kids only! WFL
On 7/8/15, rwg <rwg@sdf.org> wrote:
On 2015-07-07 06:04, Henry Baker wrote:
FYI -- Modern day antikythera device?
https://en.wikipedia.org/wiki/Antikythera_mechanism
http://3dprint.com/79049/3d-printed-extreme-reduction/
3D Printed Extreme Reduction Gearing Device Offers Exponential Force of 1 by 11 Million
"The multi-colored, 3D printed device is compact, with separate gears designated by the multi-colored design skipping a ‘tooth’ with each turn. With a crank and planetary gears built into the first gear or ring, it works to drive the next ring, which moves in the opposite direction. This means that the green ring is moving forward, and the red ring is moving backward, almost at the exactly the same speed, with the net effect being a one to eleven million gearing ratio due to an algorithm developed by van Deventer."
Good grief, van Deventer has just come up with a golden gear ratio: https://www.youtube.com/watch?v=e6epepGdnmg Caution: You can disappear for days watching van Deventer videos. --rwg
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