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Unread 18-01-2012, 08:06
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JamesCH95 JamesCH95 is offline
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Re: Help with Launcher

You want seemingly insane roller speeds to get good shots.

Squirrel has posted some really good videos and specs on his team's shooter. They're rocking about 4,000rpm axle speed with a single 8" wheel. That's about 42 m/s surface speed on their shooter.

Our shooter is substantially slower, around 6.4m/s and we're getting around 2.3m range with a high-arc shot (65deg from horizontal) with no roller slippage. This is about 70% of 'ideal'. Our range is very limited even though we have over twice the motor power of Squirrel's shooter. We are rebuilding our prototype for a much faster roller speed and using smaller, lighter, less powerful motors.

TL;DR notes:

-go for very fast roller speed
-ball-park 70% free speed for ideal trajectory calcs
-power/torque matters, but rollers/wheels will store lots of energy
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