Sprinkler system valve as a pneumatics quick Release valve

[Tank2010]

We are playing with the idea of using a sprinkler system valve as a quick release valve for releasing the air out of the cylinder quickly. We were wondering if someone has done this and would mind sharing or is it against the rules?

[Andrew Schuetze]

Originally Posted by Tank2010

is it against the rules?

Not legal and please at least download and look at the competition manual before posting and asking if it is allowed.
Here is a link to the pneumatics manual if you want to learn about how to incorporate them into your robot. And from the Robot Manual, see section 8.3.9 Pnuematic system
specifically rule

<R71> To satisfy multiple constraints associated with safety, consistency, robot inspection, and constructive innovation, no pneumatic parts other than those explicitly permitted by the Pneumatic System Rules may be used on the ROBOT.

And

<R72> In addition to the items included in the KOP, pneumatic system items specifically permitted on 2010 FRC ROBOTS include the following items. All included items must be "off the shelf" pneumatic devices rated by their manufacturers for pressure of at least 125psi, and used in their original, unaltered condition (except as required for assembly with other components).

A automatic water sprinkler value is by definition not a pneumatic device.

[martin417]

Wow, how many ways does this violate the rules?

1) all components must be rated for 125 PSI air pressure. Sprinkler valves are generally PVC, and as such are not rated for pressurized gas (air)

2) Max Cv =.32 for all valves. I don't know what sprinkler valves are rated at, but I would guess >3.2, an order of magnitude more than allowed.

3) max inlet size 1/8 NPT. The smallest sprinkler valve with which I am familiar is 3/4" NPT. again, way out of bounds.

In short, don't even think about it.

[eaglecat]

4) No other solenoid actuators are permitted except for the one(s) in the festo pneumatic valve. (OR equivalent specs of another manufacturer... I had recalled there being a "NOTE 1" on the excel file for KoP... there is not such a note, a hydraulic sprinker valve is not an equivalent pneumatic valve. Look for purpose built. Maybe a paint ball gun has a device for air release quickly where a servo could power the "trigger"?)

- eaglecat (John)

[Vikesrock]

Originally Posted by eaglecat

LOL

4) No other solenoid actuators are permitted except for the one(s) in the festo pneumatic valve.

- eaglecat (John)

LOL

Wrong!

It is important to know the rules well when responding to questions here and even more important if you are going to poke fun at others due to their lack of rules knowledge.

The appropriate rule here is <R72-C>

<R72> In addition to the items included in the KOP, pneumatic system items specifically permitted on 2010 FRC ROBOTS include the following items. All included items must be “off the shelf” pneumatic devices rated by their manufacturers for pressure of at least 125psi, and used in their original, unaltered condition (except as required for assembly with other components).
.....
C. Solenoid valves. All such valves must have a maximum ⅛” NPT port diameter, and a maximum Cv of 0.32 (if non-KOP valves are used, the team will be required to provide part documentation validating that the valves meet these constraints).

Any valve that meets the Cv, port size and pressure rating spec may be used (unless it violates another rule, I can think of at least one that is possible, but very unlikely)

[eaglecat]

As an engieneer of heavy machinery, we often use solenoid actuators. Specifically they are located in the pilot hydraulic valves that actuate the main hydraulic valves on our wheel loaders. (Electro-hydraulic designs.)

We have at times tested these on the bench. They get very warm if accidentally left on at full current. To say the least. They are large electro magnets. Will easily melt nearby electronics and burn tiny hands.

Electronic solenoids are EXPLICITLY banned. Given my above experiences, i posit this is due to safety.

Well, banned except for the itsy bitsy tiny 20 wind thing in the Festo.

You have many options, other than that for your design. Pilot pneumatic (though I have not seen it done) is amongst them. Actually would be quite ingenious. HOWEVER please read the rules, it gains you nothing, as the largest tubing you can use and only tubing size you are allowed to use (from what I read there and am told) for pneumatics is the small stuff in the KoP. Just different colors allowed.

But, in short, in searching the FESTO site, they have a "quick release version"... probably (my guess) is they use a finer wire lower O2 wire with 2x the windings to make a more powerful magnet in the same size... maybe neodenium instead of cobalt... same "juice up" linearly used radially in low versus high end model plane motors. (my inspiration for engineering) however, see my post about air resistance. I will be over the next few days finishing one about kicker design. It isn't all about fast. It is a lot about mass. Consider trying to add a lever to your pneumatic design, or looking at the "foot" mass... too high (hard to accelerate) or too low (much less than ball mass)? It is an Inelastic Collision with a CoR of about 60%... give or take, for the lower 0.62 bar inflation compared to FIFA testing at 0.8 bar.

- John (eaglecat)

[Vikesrock]

Originally Posted by eaglecat

Well, banned except for the itsy bitsy tiny 20 wind thing in the Festo.

Once again, the Festo kit valve is NOT the only allowable pneumatic solenoid valve. Please stop posting this to avoid confusing people.

For example this SMC valve is legal:
http://www.coastpneumatics.net/displ...QZ2121-6LO-N7T

This MAC valve is also legal:
http://www.macvalves.com/products/Th...mall/36/36.htm

I'm sure there are MANY, MANY others that meet the specs required by the manual as well.

The distinction is fine, but important for those looking for additional parts.

[ayeckley]

Originally Posted by eaglecat

Electronic solenoids are EXPLICITLY banned. Given my above experiences, i posit this is due to safety.

Electric solenoid *actuators* are prohibited, but electro-pneumatic solenoid valves are not. This seems to be the misunderstanding.

[fsgond]

Without going into the rules, I have used the valves for 120 PSI air and they work fine. the main problem that you would run into is that the system usually run on 48V AC.

Just FYI

[Tank2010]

Originally Posted by ayeckley

Electric solenoid *actuators* are prohibited, but electro-pneumatic solenoid valves are not. This seems to be the misunderstanding.

Originally Posted by Vikesrock

Once again, the Festo kit valve is NOT the only allowable pneumatic solenoid valve. Please stop posting this to avoid confusing people.

For example this SMC valve is legal:
http://www.coastpneumatics.net/displ...QZ2121-6LO-N7T

This MAC valve is also legal:
http://www.macvalves.com/products/Th...mall/36/36.htm

I'm sure there are MANY, MANY others that meet the specs required by the manual as well.

The distinction is fine, but important for those looking for additional parts.

Ya sorry every one It was a crazy thought that poped into my head thanx for all the good Ideas that are legal. We werent sure what was out there and couldn't seem to find what we were looking for thats what brought us to post the question here. Thanx to those who gave me a kick in the pants for even thinking about useing the Sprinkler system valve and not even trying to help.

[Taylor]

Originally Posted by Tank2010

We are playing with the idea of using a sprinkler system valve as a quick release valve for releasing the air out of the cylinder quickly. We were wondering if someone has done this and would mind sharing or is it against the rules?

It is against the rules.
HOWEVER
We have done it, we are very satisfied with the results, and we plan to continue using the exact system you described in the future.


...


On our T-shirt cannon.

[MrForbes]

Yet another illegal way to release a lot of air at once is to use a small cylinder to directly actuate a gate valve.