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Unread 03-12-2015, 10:49
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AKA: Allen "JAG" Gregory
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Re: [Behind the Lines] Ep. 5 Mechanism Design with 118, 3847, and 973!

Quote:
Originally Posted by JesseK View Post
The only thing I feel is missing from the shooter portion is a tip about design of experiments: if we're trying to figure out the "best" wheel, account for larger wheel edge speeds by slowing the motor down. Of course the 8" wheel will do better at the non-adjusted speed, even if the grip/wear is a quite a bit worse than its 4" counterpart.
We were pretty short on time so I couldn't really do any of the simple math required for figuring out your ideal exit velocity, etc. Larger wheels may not perform better if you don't have enough torque to keep them going. Direct driving a larger wheel at to high an rpm will have much worse results than with a smaller wheel especially if the wheel slips on the game object instead of transferring energy. This is why linear shooters in 2013 had to start with slower spinning wheels and increase the rpm of subsequent wheels/motos. Also your overall strategy and packaging goals (how much room you have for your shooter) will play a role in wheel diameter selection as well.
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