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Unread 12-01-2012, 14:15
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JamesCH95 JamesCH95 is offline
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Re: Team 3489's Catapult Prototype

Quote:
Originally Posted by JesseK View Post
You can use a lead screw with 80/20 linear slides to effectively shorten the arm when you want, thus lowering the ball speed at launch. You can also just sit at the slot and launch the balls 50 feet. However, IF YOU DO THIS, make sure your arm never extends up over 60 inches.

You may also be able to put 2 solenoid valves on the cylinder such that you can have 2 different working PSI's, giving you a high-pressure normal range and low pressure ultra-short range (for when you're right next to the thing). Double check the rules though; I know after 2008 they changed the pneumatic rules up a bit to prevent specific instances of multi-valve issues from occurring. You may also be able to hook a servo up to flow-control valves to limit the speed at which the cylinder fills if the multi-valve thing doesn't work.

The hardest part of this will be side-side accuracy, IMO.
I was just made aware of this rule by SIRI (CD user):

<R78> The outputs from multiple valves may not be plumbed together into the same input on a pneumatic cylinder.

Just FYI.
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