Rules on Pneumatic Cylinders

[xForceDee]

Currently I am thinking of possibly trying to punch the balls with a pneumatic cylinder. In the past, FIRST has put restrictions on things such as bore size and shaft length of the cylinder (at least I am pretty sure). I can't seem to find any rules regarding this in the rules however in the current manual. Could someone please stop me before I put a 10 inch bore diameter piston on my robot. :D

[MrForbes]

Used to be you could only use a few specific sizes....that rule went away several years ago.

[xForceDee]

So just to be 100% clear, there is no restriction on bore diameter or shaft length?

[MrForbes]

If you don't see a restriction, it's because there isn't one.

keep in mind how much air the compressor can pump....I guess they figured out you don't need to be limited in size, because nature takes care of it.

[ksafin]

The biggest change to this year is no Cv restriction on solenoids. This used to be pretty low, limiting airflow and making some things impractical. This year you can have a pretty high Cv solenoid allowing high airflow and making pneumatics more practical.

[Owen Makin]

The biggest change to this year is no Cv restriction on solenoids. This used to be pretty low, limiting airflow and making some things impractical. This year you can have a pretty high Cv solenoid allowing high airflow and making pneumatics more practical.

Can you please quote the rule, i could not find that change in the rule book. Thank you.

[CalTran]

There was no rule restricting the CV on solenoids, so that would be why you can't find it. Therefor, any CV solenoid less than $400 is fair game.

[Steven Donow]

Can you please quote the rule, i could not find that change in the rule book. Thank you.

There is no rule-and that's the change. If you read the 2013 manual, it's letter C of R78:

C. Solenoid valves with a maximum 1/8 in. NPT port diameter, and a maximum Cv of 0.32,

That's from the 2013 manual, whereas R77 (the comparable entry in this year's manual) this year states:

Solenoid valves with a maximum 1/8 in. NPT port diameter,

[IndySam]

Can you please quote the rule, i could not find that change in the rule book. Thank you.

There is no rule limiting CV. You can't quote a rule that doesn't exists.

4.10.4 R77
C. Solenoid valves with a maximum 1/8 in. NPT port diameter,
E. Additional pneumatic tubing, with a maximum 0.160 in. inside diameter, functionally equivalent to that provided
in the KOP,

These will be the limitations on flow so don't expect to fill a 2" cylinder quickly.

[cmwilson13]

theirs no limit to the number of cylinders you can use though. so 3 1 inch cylinders have similar force to 1 larger cylinder yet you can have 3 inputs vs 1 so multiple small cylinders gives you faster extend time then 1 larger cylinder

[PAR_WIG1350]

theirs no limit to the number of cylinders you can use though. so 3 1 inch cylinders have similar force to 1 larger cylinder yet you can have 3 inputs vs 1 so multiple small cylinders gives you faster extend time then 1 larger cylinder

Depending on how they are plumbed, yes. however there are ways to do it and still restrict flow significantly, which should be avoided.

[cmwilson13]

unless they have changed the rules and they may have the rules require 1 valve for 1 cylinder. so if its done that way you have significantly more flow

[AustinShalit]

R90 prevents this, "The outputs from multiple valves may not be plumbed together"

[engunneer]

R90 prevents this, "The outputs from multiple valves may not be plumbed together"

Hence using three small cylinders to do the job of one large cylinder.

[Owen Makin]

There is no rule-and that's the change. If you read the 2013 manual, it's letter C of R78:



That's from the 2013 manual, whereas R77 (the comparable entry in this year's manual) this year states:

Thank you, and everyone else for their reply, our team wouldn't have noticed that small yet significant change.