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Unread 10-01-2012, 19:53
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Re: "Pitching Machine" motors

Quote:
Originally Posted by Mr_I View Post
As a side note: Back in the day ('07 to be precise), when we were trying to throw Poof balls, we were getting an amazing lack of distance, sometimes maybe reaching 6'. This would have been pitiful in competition.

On a whim we decreased the space between the spinning wheels, thus "squeezing" the balls more. Suddenly, we were exceeding 30' on a regular basis, without any other changes to the thrower.

Photo of work in progress. Can't find one "proving" the distance, but the turned faces are an indication.
Decreasing the space increases the linear momentum and decreases the angular momentum imparted to the ball. I think that squeezing this year's ball by ~3 inches total (i.e. 5" between wheels at their closest point) is a good starting point for experimentation to determine how to impart less spin to the ball (spin from each side cancels out, so that energy is wasted) and impart more linear speed (which does not cancel out).
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