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Unread 17-02-2012, 08:17
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Re: Wheel shooter gearing

Quote:
Originally Posted by Ether View Post
Does this agree with your numbers?
69.8 feet/sec wheel tangential velocity,

34.9 feet/sec ball exit velocity,

38.1 feet theoretical* max range


* no drag, no magnus

Ha, I screwed up. When we cut the launch angle in the guide I measured it from the normal plane rather than the parallel plane. So it's inverted with a flatter trajectory than we want. Theoretical distance is the same, yet we need the extra height for the high goal. We also comepletely re-fabbed the shooter shaft since there was a slight wobble, and relocated one of its bearing blocks since it was slightly out of alignment. All told, I think we're back up to 30 feet-ish (ball barely peaked before it hit the wall at 15 feet) with the flat trajectory. Once we finish sensor wiring tonight I'll know more.

There would be significant magnus effect if the ball's trajectory went further or higher -- we hit the wall at probably > 70 degrees angle of incidence (20 degrees from parallel with the floor) and the ball came almost straight down due to the backspin. May make for some interesting layup shots.
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