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Unread 09-01-2006, 13:32
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Re: Calculating Angle to fire at

Quote:
Originally Posted by Kevin Watson
Air resistance at these velocities can be effectively considered to be zero. Spin stabilization of projectiles is done to decrease the effect of orthogonal forces like wind. I would just stick with the projectile motion equations, which should work just fine at these velocities and distances.

BTW, I've seen a 'bot that can use the camera to position itself and fire ball after ball into the target, so I know that teams can do it if they put the effort into it.

-Kevin
Using your standard Fd=1/2*Cd*rho*A*v^2, I get a drag force of over 1N. On a 183 gram ball, it works out to an additional 6 m/s^2 deceleration. Is that really negligible?

Assumptions: Cd=0.5, rho=1.29 kg/m^3, A = (7/2)^2*pi in^2 = 0.025 m^2, v=12 m/s

I know it's not as significant as if we were firing ping-pong balls, but I don't think standard ballistics will give much accuracy without a large fudge factor.
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