Pneumatic Ball Puncher

[jacqlecl772]

well my team original idea was to use pneumatic but we simply could not get the piston to extend fast enough to push the ball far enough. We even called are pneumatic guy to ask him if he had any cylinders that could open with such speed and force but he told us that he could not think of any way to do it. So i would say that to my knowledge there is no way of using pneumatic to shoot the ball in to the high goal, however it may be possible in the low goal.

Your best bet is to prototype some different shooters and pick the best one !

[PVCMike]

I am continuously surprised by the discouraging comments, especially by adults and mentors on this forum. FIRST is about encouraging these students to TRY things, think outside the box, see whats possible, yet this thread is full of the opposite.

There is a big difference between "we have not been able to figure out how to do it." and "it's impossible" or "don't even bother." Let's be constructive not discouraging.

[themccannman]

Originally Posted by PVCMike

I am continuously surprised by the discouraging comments, especially by adults and mentors on this forum. FIRST is about encouraging these students to TRY things, think outside the box, see whats possible, yet this thread is full of the opposite.

There is a big difference between "we have not been able to figure out how to do it." and "it's impossible" or "don't even bother." Let's be constructive not discouraging.

Most of us aren't trying to discourage students, were trying to save you from wasting your build season. 6 weeks is not enough time to try every possible method and pick your favorite. A large portion of the design process is brainstorming what is feasible and what isn't so you don't waste your time. We will be ready by week 1, and I hope we can get as many other teams as possible ready by then too.

[LH Machinist]

One method of shooting using pneumatics.

[yara92]

Originally Posted by LH Machinist

One method of shooting using pneumatics.

can you Explane how this works

[cmrnpizzo14]

Originally Posted by yara92

can you Explane how this works

Essentially what you do is actuate the larger piston so that the air travels through the solenoid into the cylinder. The smaller cylinder is acting like a latch and is blocking the large cylinder from extending. Once the air is in the cylinder and the cylinder is supposed to be extended you retract the smaller cylinder out of the way ("unlatching" the large cylinder. Then the large cylinder will extend much more rapidly than it would have without the latch because the extension speed will not be dependent upon the air flow through the solenoid. It is basically a way to get around the air flow problem that many people experience with the solenoid.

If you want a more detailed explanation we did something like this on our 2010 bot. PM me and I can try to explain it better.

[Al Skierkiewicz]

Originally Posted by cmrnpizzo14

Essentially what you do is actuate the larger piston so that the air travels through the solenoid into the cylinder. The smaller cylinder is acting like a latch and is blocking the large cylinder from extending. Once the air is in the cylinder and the cylinder is supposed to be extended you retract the smaller cylinder out of the way ("unlatching" the large cylinder. Then the large cylinder will extend much more rapidly than it would have without the latch because the extension speed will not be dependent upon the air flow through the solenoid. It is basically a way to get around the air flow problem that many people experience with the solenoid.

If you want a more detailed explanation we did something like this on our 2010 bot. PM me and I can try to explain it better.

Cam,
The cylinder moves out to the machanical stop but it doesn't have any higher pressure air or greater volume. When the mechanical stop is removed, air still needs to flow behind the piston and that air passes through the fittings as if the primary valve was opened. Or am I missing something?

[jijiglobe]

Someone on my team talked about using multiple solenoids to actuate a single piston. This would bypass the problems of solenoids not letting enough air through in enough time. Does anyone know if this is a thing you can do? It seems a little sketchy.

[MechEng83]

Originally Posted by jijiglobe

Someone on my team talked about using multiple solenoids to actuate a single piston. This would bypass the problems of solenoids not letting enough air through in enough time. Does anyone know if this is a thing you can do? It seems a little sketchy.

R90: The outputs from multiple valves may not be plumbed together.

[martin417]

Originally Posted by jacqlecl772

well my team original idea was to use pneumatic but we simply could not get the piston to extend fast enough to push the ball far enough. We even called are pneumatic guy to ask him if he had any cylinders that could open with such speed and force but he told us that he could not think of any way to do it. So i would say that to my knowledge there is no way of using pneumatic to shoot the ball in to the high goal, however it may be possible in the low goal.

Your best bet is to prototype some different shooters and pick the best one !

I can guarantee that it is possible to launch the ball into the high goal using only unassisted pneumatic cylinders. In 2008 we were able to fire the ~8 pound, 40" diameter trackball way farther than would be required for this 2 1/2 pound 24" diameter version