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Unread 15-01-2014, 12:37
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AKA: Craig Rochester
FTC #8470 (Team Technado)
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Re: Ball Flight Model

Quote:
Originally Posted by Ether View Post
... except I can't tell from your video if your piston is over-center in the loaded position. If not, how are you holding (and releasing) it?
Hi Ether,

Not over-centered, hadn't thought of it; great idea for "cocking" mechanism. Thanks for that!

In the sketch, the loaded position would be determined by hard stops and/or rod fully retracted. I was trying to evaluate the feasibility of shooting the ball with cylinder stroke only (no spring storage, no trigger release).

After seeing the video of the team 1726 catapult prototype, I'm thinking I have missed an important pneumatic dynamic: the inertia of the ball/launcher and the pressurization of the cylinder during the initial acceleration. We struggled with the Cv limitations of the solenoid valve when working on Rebound Rumble ball shooter prototypes. Your over-centered system looks like an even better way to deal with CA flow restrictions.

Your feedback, as always, is much appreciated.

NOTE: fixed error in previous post re "increased moment"