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Unread 06-02-2017, 14:00
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Re: Poll: Reasonable and achievable, or shooting for the stars?

Quote:
Originally Posted by Kevin Sevcik View Post
18 Ah @ 12V = 12*18 Watt-hours * 60 min/hr * 60 s/min = 777600 Watt-s or Joules. Escape velocity is 11186 m/s. So 777600 = 1/2 * m * (11186)^2 = 12.4g. Balls weigh 70g, so you'd need 6 batteries charging your ball launching system to reach escape velocity. Not counting drag, etc. A properly designed charging system could probably send a penny into solar orbit, though.
According to JVN's Spreadsheet, if we can get the load on the motors down to 0.04 lbs of resistance using some space-age materials on the wheel it is theoretically possible to power a ball to terminal velocity using just 8 775PROs and a wheel that is 30' in diameter.

So 6 batteries it is! If we stick a bank of capacitors in there, maybe that will prevent RoboRIO brownout?
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