Flywheel Shooter Speed

[Ekcrbe]

68's shooter in 2012 used an 8-inch diameter wheel (on an 8-inch ball) and ran at 2000 RPM. That was good for shooting from the front of the key (~12 feet away if I remember correctly) into the top hoop (8' 2" high) with a release angle of ~50 deg above the horizontal. Unfortunately I can't quote an empirical exit velocity.

Side notes on shooter design: we determined that there were two main reasons for that shooter's success (and I believe this will carry over to this year given the similar balls). One was the fact that it had a lot of compression as the ball entered (about 2.5" or 30%) but the compression decreased as the ball moved upward and ended with the ball leaving the wheel and rolling only against the hood, which was by that point straight rather than arced. The other was that the ball had a lot of wrap around the wheel—about 135 deg, or 9.5" of surface. The high compression and long distance allowed the shooter to impart a lot of energy into the ball with a relatively low wheel speed, and the tangential extension on the hood allowed the ball to decompress gently and guided the ball out of the shooter, eliminating any inconsistency due to the "pop" as the ball rapidly returned to its normal size upon exit from the wheels, which had been a problem in our earlier designs.