pic: 1251 Prototype v 1.2

[Andrew Blair]

The size of the wheel has nothing to do with the RPM of them (Unless you say that their mass slows down the system). If we know the output speed of the Kit gearbox, and we know the ratio to the the wheels, we can, with some error, find the RPM of the wheels. Now, if we were looking for the linear speed from a reference point on the wheel, then wheel size would matter.

[Tom Bottiglieri]

Originally Posted by Andrew Blair

The size of the wheel has nothing to do with the RPM of them (Unless you say that their mass slows down the system). If we know the output speed of the Kit gearbox, and we know the ratio to the the wheels, we can, with some error, find the RPM of the wheels. Now, if we were looking for the linear speed from a reference point on the wheel, then wheel size would matter.

Who says the trannies are running at full power?

[Andrew Blair]

Originally Posted by Tom Bottiglieri

Who says the trannies are running at full power?

Thats one of the easiest assumptions. They're running the motors straight off of the battery, so the speed of the output is defined only by the battery voltage. Its rather easy to say that they were running a fairly charged battery; most people don't run a battery to nothing and then use it to power a launcher. An easier assumption than the estimation of the size of those two sprockets.

[i_am_Doug]

EDIT: im now guessing your team number ;p 1251.

[cire]

Looks like 1269 RPM to me

gear ratio * free speed of kit transmisson
3:1 * 423 rpm = 1269 rpm

edit - I estimated that the larger sprocket was 36T and the smaller one was 12T by looking at the picture.

[Rick TYler]

I know I'm coming late to the party, but 1,250 rpm, plus or minus two weeks.

(Bonus if you recognized the obscure movie reference.)