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Unread 11-05-2015, 09:36 PM
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Re: 110ft/s (75mph) robot design

Picture!

Caveat - doesn't account for battery & wiring resistance, which affects available power. Also doesn't account for wind resistance, which would be a big deal at higher speeds. Also, you'll want ROUND SHAFTS so your bearings can be ABEC rated for maximum efficiency.

Edit - added the 2nd picture, but it doesn't take into account a 2nd gear. 'Current from friction' is 38 amps and is total, with the above caveats and is after full acceleration is reached. So you're well above 38 amps for 16 seconds. Because physics will most definitely account for what I don't account for, I don't know if it's totally plausible.

On the surface, if you could shave another 10lbs off of it (no shifting, carbon fiber frame, only 4 wheels so it's a straight line, belts) then your time & current are MUCH lower.

(Not sure why we want to combine MPH with meters as metrics for a design ... but ok...)
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Last edited by JesseK : 11-05-2015 at 09:51 PM.