limits on pnuematics
 

The way I read it, the restricted parts list states that only 3 cylinders may be used, however the pneumatics manual refers to ordering more cylinders, over and above the 3 free custom ones.

Can anyone shed any light on this one for me?

from what I've heard you can only use a max of 4 pneumatic cylinders on your robot

You can use the 1.5" bore actuator which was distributed in the Kit of Parts, and you can custom order 3 actuators in compliance with the order form found in the Pneumatics Manual. This makes a maximum of 4 actuators on your robot at any given time.

hrm, that sounds about right, one in the kit plus 3 more to order, but it seems quite a heavy restriction on a game that will pontentially make great use of pnuematics

yeah that's true, because we're planning to have a shifting gear transmission and that uses two of our cylinders already

wait, the three custom cyliders are free? where was that in the manual? *drools* freeeee stuuuf!

I think you can get up to 4 that are free

Looking at the restricted parts list, in addtion to those in the kit, we can use only three more cylinders on the robot :ahh:

The order form is the last page of the Pneumatics Manual.

Page 7 of the Pneumatics Manual:

Quantities of no charge custom cylinders will be limited to 3 per team to insure that custom cylinders will be available late in the 6 week period. In the even that you require more than three cylinders, please fax us your requirements and we will attempt to provide them as long as supplies last.



So, in other words you can order 3 custom cylinders for free. If you need another, they will try to accommodate it but no promises. However, as said in the additional parts, you can only use 3 custom ordered cylinders on your robot.

Darn, we need 4 custom... I hope we will be able to use them, FIRST has not come out and said anything about it yet.

<Waits patiently for next update> :rolleyes:

hmmm...that's weird I'm pretty sure I read 4 on that order sheet provided from SMC??

Number of cylinders
 

The question is a good one, and has been asked on the offical FIRST question site, and is awaiting an answer.

The rule from last year, which I'm confident hasn't been changed for this year, is a total of 4. The one in the kit (from Parker), plus 3 custom which can be ordered on the order form on the back of the pneumatics manual.

Until FIRST 100% confirm this, you should design around this, as it could only get better.

Regards,
Scott358

PS - I work for a pneumatics company who is a contributor to the parts kit, so I am pretty confident this is the case.

Last Year was Different
 

Unless FIRST clarifies, last year was slightly different.

Last year we could have a total of 4 cylinders, but one of them didn't have to be the one in the kit. This year they specifically state that you get the one in the kit plus 3 custom. I hope this rule changes to exactly what is was last year: up to 4 cylinders, all from custom pnuematics order form.

I will wait and see.

-Paul

Are there any limits on the number of tanks you have?

We have a pnuematics test bot hooked up with 4 2" resevoirs, which are filled by two compressors running together. Even then it takes a while to pump all the way up, but its worth it to be able to hit one switch and have 3 or 4 cylinders go off at once.

You dont need any tanks
 

If you use the rectangular AL in the kit for your frame ......use it as a storage tank its a no brainer.Install bulkheads sealed with RTV attached with rivets and put ports where you need them ..........we screw the valve in the ports.Last year a team strung ALL the tubing supplied in the kit around the bot and it was equal to the tank volume but 1/10 the weight.

Lets keep thinking creativly ........thats what robotics is all about.

Jim H

I strongly recommend that teams DO NOT follow that advice. This is not creativity, it is cheating.

See this thread.

-dave

I agree that this violates the rules. This would qualify as a custom pneumatic device and that is strictly prohibited. If you were joking, please don't abuse the forums and waste space. These forums are meant for technical discussion, not for misleading comments.

I agree however, that the tubing can be used as an accumulator, but I wouldn't recommend it because of the space it uses up.

Re: You dont need any tanks
 

Excellent, creative idea... but it's not legal. See rule M12 and the warning after this rule.

Andy B.

If you're that desperate for air storage use the extrra tube that came with the kit. Last year we figured out it had slightly more volume than one of the supplied reserviors and weighed slightly less. But we didn't have the volume in the robot to make it work.

Do it yourself pressure vessels (what Mr. Harbison was proposing) are a VERY BAD IDEA.

Engineering is the continual exercise of judgement. That includes judgement on when you are getting in over your head. I am a licensed mechanical engineer. In this state that means that I am legally qualified to design and build pressure vessels. BUT because that is not what I normally do, I would never attempt it.

I am just not familiar enough with the design methodology and safety standards to do a good enough job to ensure I don't kill somebody. If I'm over my head on something like this, chances are you are too.

Not only is it against the rules it is just plain STUPID. When you pull something like this you are playing with the eyes, limbs and maybe lives of everyone around the robot. You have created a potential bomb.

Pnuematic components are fabricatred to comply with strict codes to ensure they do not fail under designed use. If they should fail, something is likely to go flying at high velocity. Very few, if any teams have the expertise on board to design their own pnuematic elements in such a way as to conform to industry standards. That is why the use of self designed and constructed pnuematics is prohibited.

DON"T DO THIS

Have we made ourselves clear?

so two compressers are legal? If so that makes my life easier :)

NO. See in the kit of parts Pneumatic Section Compressor Qty 1 listed

thought it was a little too much to hope for....

Re: Number of cylinders
 

And in case anyone missed it, the answer from FIRST is:

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Posted By: first Posts: 168 / Registered: Dec, 2002

You must use the cylinder that was provided and you may get three more cylinders using the Custom Cylinder Order Form..
See the Part Use Flowchart.

36F

[Edited by: first on Jan 10, 2003 5:18 PM]

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Which is sorta strange. We MUST use the cylinder that was in the kit? What if we don't need that one?

Bruce C.

Re: Re: Number of cylinders
 

I agree it's sort of strange to REQUIRE using that cylinder, But you could always use it as an auxiliary accumulator. That is acceptable as long as the piston does not move and you do not modify it in any way. If it gives you enough extra volume that you don't have to recharge your system during a match then you could leave off the compressor and save weight too.

It would be acceptable as long as you only put 60psi in it. The pneumatics rules aren't very clear this year about what can be 120 and what has to be <60, but my guess is the only thing allowed upstream of the 60psi regulator is the compressor, pressure switch, gauges, tanks, and fittings.

The pneumatics manual states: "This regulator has a maximum output pressure of 60psi. This regulator must be
placed in-line right after the tanks to limit the pressure to all working circuits to 60psi."