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Unread 10-01-2013, 11:37
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Nuttyman54 Nuttyman54 is offline
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Re: pic: The Cow that Jumped over the moon!

Quote:
Originally Posted by dondanvm View Post
I used the calculation method from this website assuming that each CIM is just under 1/2hp and weight roughly 3 lbs. You could use all 6 cims or just 1. The math is complicated, but it walks your through pretty well. You certainly would not have a lot of weight room left but it is possible from my calculations.

http://www.heli-chair.com/aerodynamics_101.html


Still, not in the spirit of the game
Yes it does look technically feasible. My calculations show 6 CIMs running at peak power on a 4ft diameter rotor (just fits within the 54" cylinder with a bit of room to spare) can generate 140 lbs of thrust. With a superlight robot, you probably could make that work. This is the most efficient rotor configuration for area, but would be nearly impossible to control well. A hex-rotor configuration is more controllable, with 1 CIM each, but you'd lose a lot of rotor area, which starts to eat into your thrust capabilities.

That being said, if you run 6 CIMs at full power continuous a) your battery will probably drop to at least half-voltage within a minute and b) the motors will likely overheat and start losing power.

All of this ignores the safety aspect, which is that FIRST probably wouldn't allow a flying robot onto their field on safety grounds. The nets are designed to contain frisbees, not runaway helicopter bots.
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