Pneumatic Cylinder Limits

[Karthik]

Another mentor pointed this one out to me, and it's also bridged in this thread.

http://www.chiefdelphi.com/forums/sh...374#post994374

This year's pnuematic rules don't mention any limits or allowable quantities of cylinders other than:

<R66> In addition to the items included in the KOP, pneumatic system items specifically permitted on 2011 FRC ROBOTS include the following items. All included items must be “off the shelf” COTS pneumatic devices rated by their manufacturers for working pressure of at least 125psi and burst pressure of 250psi, and used in their original, unaltered condition (except as required for assembly with other components).

So since there's no mention of any additional cylinders in the manual, it would mean we're limited to what's in the KOP. Looking at the KOP checklist we see that only cylinders listed are the three provided with the Bimba order form. So... This begs the question. Are we only allowed to use a maximum of three cylinders this year? Must they be identical to cylinders available on the Bimba order form? This would be a big change from past years in terms of quantities and changes a lot of traditional design ideas.

Am I missing something here? This will definitely be the first Q&A entry we'll be posting.

[Vikesrock]

Good catch!

Looks like they either put much larger restrictions on pneumatics this year or in an effort to open things up even further created some unintended issues.

I think some GDC clarification is definitely the way to go.

[Madison]

This has been clarified in TU2. http://usfirst.org/uploadedFiles/Rob...0Update_02.pdf

[artdutra04]

Originally Posted by Madison

This has been clarified in TU2. http://usfirst.org/uploadedFiles/Rob...0Update_02.pdf

This would imply to me that as long as the COTS pneumatic cylinders/accumulators meet the pressure regulations in <R66>, any size or quantity of pneumatic cylinders or accumulators is legal this year.

If so, I really like this ruling. I've long been an advocate of simpler rules with more relaxed restrictions (particularly is such a restriction is already limited by other physical conditions), and over the past few years lots of restrictions have been lifted or eased (tape is allowed, any compressor less than or equal to KoP compressor specs is allowed, freedom to choose any combination of the four Banebot motors, now more freedom of pneumatic cylinder/accumulators).

[Chris is me]

Awesome ruling!

Seriously, this is really cool. Pneumatics are wide open this year, it makes a lot of things possible!

[Karthik]

Wow, this ruling almost seems too good to be true. This should be easier on both teams and inspectors. I am thoroughly impressed.

[Zuelu562]

Originally Posted by Karthik

Wow, this ruling almost seems too good to be true. I am thoroughly impressed.

I have to agree. The hint(s) this year plus this ruling shows to me the GDC is becoming sane...either that or FIRST is making it easier on rookies and vets....

[dlavery]

Originally Posted by Zuelu562

I have to agree. The hint(s) this year plus this ruling shows to me the GDC is becoming sane...

Then what were they before?





.

[DonRotolo]

Originally Posted by dlavery

Then what were they before?

Um, I'd rather not say.

Edit: They were merely cool before. Now they are cooler than ever. And not in a thermal sense.

[bobosalad]

What are the pros cons of having a lot of air storage vs little storage?

[Chris Fultz]

Lots of Storage - depending on your system needs, you might not need to have the compressor on board. you can charge the system before the match. this can be a significant weight savings.

another benefit is that even if you do have the compressor on board, it might not need to run very often. this conserves your power.

Little storage - you save the weght of the reserviors. the negative is that your compressor may run several times during the match, using a lot of electrical power.

The decision depends on your pneumatic needs. If all you are doing is shifting transmissions, then a large reservoir may allow you to shift several times without needing a compressor on board.

[DonRotolo]

Originally Posted by Chris Fultz

the negative is that your compressor may run several times during the match, using a lot of electrical power.

It is also possible that, at times, the compressor may be unable to supply enough air volume to maintain system pressure, degrading the performance of the pneumatics. Additional storage tanks are a larger 'reservoir' from which air can be supplied.