Using a Plunger System to Launch Balls

[JamesCH95]

Good catch on the rule. IIRC it was legal up through 2010 when I last looked. Always pays to double check

[HFCHS-NASA]

We are trying to avoid pneumatics because we want to have the precise control of electric motors. How does a spring and cam system work? That sounds what we want to do.

[EricH]

Originally Posted by HFCHS-NASA

We are trying to avoid pneumatics because we want to have the precise control of electric motors. How does a spring and cam system work? That sounds what we want to do.

http://www.chiefdelphi.com/media/photos/31538
http://www.chiefdelphi.com/media/photos/31539

That should get you started on some things of that nature.

[pfreivald]

Originally Posted by HFCHS-NASA

How does a spring and cam system work? That sounds what we want to do.

A cam is just a plate or something of the sort with an irregular shape. You attach it to an output shaft (geared up/down as necessary) and use it to stretch a spring or other elastic material (surgical tubing, for example). As it goes around, the object slips off of the cam and slams to equilibrium position. You can stop the cam each revolution using a sensor of some kind, so it doesn't fire continuously.

This video, http://www.youtube.com/watch?v=_hTyXQUgYLE at 1:49 shows a cam-powered kicker running.

[Brandon Zalinsky]

we messed with a pneumatic/spring plunger mechanism and we couldn't figure out how to make the ball fly farther than 10 feet without dumping our entire tank. If you find a way to do it well, please share!