16:49 <Greys> anyall up for mathgineering time?

16:51 <Greys> so, say I have a circle of arbitrary size, and it is resting on two other circles of size R, who are then engaged with two other circles of size r, and the r circles have a belt going around them that encircles the arbitrary circle

16:51 <Greys> http://i.imgur.com/k4fnHHD.png

16:52 <Greys> white = r, green solid = R, green dashed = arbitrary

16:53 <Greys> what is the drive ratio between r and R that results in the belt travelling around the arbitrary circle at the same speed that the R circles rotate it

16:53 <Greys> 1:1?

16:54 <Iskierka> you don't have a drive ratio between the cirles as they're in contact at the surfaces and their surface velocity will always be the same

16:55 <Iskierka> the belt will always travel at that surface velocity

16:55 <Greys> there will need to be gearing between them, I abstracted that out

16:55 <Greys> so as long as the gearing is 1:1, the belt will travel at the correct speed

16:55 <Iskierka> yes, if the problem is described accurately

16:55 <Greys> I think it is

16:56 <Greys> and gearing ratios are based entirely on tooth count, not radius, right?

16:56 <Greys> (radius is a result of tooth geometry, but ignoring that)

16:58 <Greys> as long as the tooth count matches the radius doesn't need to match; because if there weren't teeth the radius wouldn't need to match

18:26 <egg> Greys: try asking your question in kspacademia, it may get more eyeballs

18:27 <egg> Greys: ah, I see Iskierka has answered already

18:27 <egg> !wpn UmbralRaptor

18:38 <Greys> egg, I'm satisfied with this answer, it makes sense