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Unread 17-05-2016, 13:13
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Re: what was the best shooting mechanism for 2016?

Quote:
Originally Posted by jijiglobe View Post
I would also argue that the main reason that the two wheeled shooter is faster is because it has twice as many motors.
It's not an argument or random postulation, it's physics. It's the difference between a ball being "rolled" or "tossed" out of a shooter. Let's make some assumptions - zero slip between the wheel and the ball, zero slip between the ball and the hood of the shooter, perfect energy transfer, wheels don't even slow down, whatever.

A two wheeled shooter contacts both sides of the ball at a certain tip speed, V. Both edges of the ball are being moved at the same speed, so the ball does not rotate at all, it is fired straight out of the shooter. The center of the ball therefore also moves at V.

Now consider a hooded shooter. The flywheel rolls one edge of the ball forward at V, and the other side of the ball is rolling along the flywheel. Instantaneously, the tip velocity of the other side of the rolling ball is zero (or is it the other way around...) - so the velocity of the center of the ball is V/2. When the ball exits the shooter (is released from the constraints placed on each end of the ball) it'll travel at the speed the center of the ball is moving.

Real world factors will make your result vary, but in general, all other things equal, hooded shooters do move balls half as fast (and half as far) as two wheeled shooters. This is not due to having fewer motors - tons of teams put more than one motor on a ball. This is just due to the dynamics of a ball rolling through a shooter.

A 775pro's power is greater than a mini-CIM, yes, but there are also good reasons not to spin your flywheel at 19,000 RPM, and tip speed is far from the only factor that determines how far your ball will fly. You probably end up gearing the 775 down to a speed closer to the mini-CIM, but with more power, which would probably reach a greater distance yeah. Too bad you can't buy those right now...
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