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Nitroxextreme 17-01-2005 13:34

Pneumatic's Rules confusion
 
i know there is another thread but it doesnt get any traffic

im very lost with these rulings about the pneumatics
we are going to use the free cyclinders from bimba
however we got a rotary from parker
Also we were lookin into pneumatic devices (ex pneumatice gripper (pre made)

Are they allowed (both the rotary from parker and/or the pneumatic devices)

Another question: is it possible to use a bimba non rotating linear pneumatic

Steve W 17-01-2005 14:03

Re: Pneumatic's Rules confusion
 
The rotary from Parker is allowed as long as it meets the same specs as Bimbas. You are not allowed to use the gripper if it comes with cylinders that are not on the allow list. You MUST use only the cylinders from the allow list. For your last question, if it is not on the list you cannot use.

Hope this helps.

Nitroxextreme 17-01-2005 14:13

Re: Pneumatic's Rules confusion
 
Thanks

However im still confused with the rules
why do they say any off the shelf pnuematic devices
(i would think this just means no home made pneumatics for safety)
and then go on to say only bimba and parker linear and rotary from the order list

If you were to buy a gripper already made that isn't a linear or rotar but more like a custom pnuematic couldnt you use any make

Why wouldnt you be able to use non rotating
When you order a normal cyclinder from bimba they always have the option
but once you go to the free FIRST section then there is no option

Greg Needel 17-01-2005 14:18

Re: Pneumatic's Rules confusion
 
the rule about any off the shelf componets deals only with fittings, solonoids, tubing...basicly anything except the cylinders and the storage tanks....

you are limited to 2 storage tanks just like the 1 from the kit and any cylinder that is the same specs at on the order form in the back of the manual.

Steve W 17-01-2005 14:22

Re: Pneumatic's Rules confusion
 
FIRST has an agreement with Parker and Bimba. They also try to level the field with other teams. The cost of the cylinders could prevent some teams from equal field. I wanted to use the non rotary as well but they are unfortunately not on the list.

Nitroxextreme 17-01-2005 14:36

Re: Pneumatic's Rules confusion
 
im really confused now
i have a contact at another team and he says that in the past they can use other pnuematics as long as the team pays out of their pocket

Also i heard that one year they allowed a team to use all SMC pneumatics

Kautz 17-01-2005 20:08

Re: Pneumatic's Rules confusion
 
There are no 1/2" bore cylinders on the order sheet only 3/4", 1-1/2" and 2" bore.So you can not use 1/2" bore cylinders of any stroke?


Thanks

jrocket567 17-01-2005 20:22

Re: Pneumatic's Rules confusion
 
It does seem a little more confusing than last year.. the best I can understand it is that you can use as many cylinders, rotary actuators, etc as you want, as long as they are listed on the custom order sheet.. but the thing that is throwing me off is the flow chart.. it states that you can use any pneumatic devices off of previous year's bots.. so if I have a 1/2in bore (they are not on the list this year) on last year's bot, can i take it off and use it this year??
j

cdawzrd 17-01-2005 21:16

Re: Pneumatic's Rules confusion
 
Well, a few years ago we used an off-the-shelf NON-CONTROLLED pneumatic device... a suction cup for carrying glass, we then in turn used a pneumatic from bimba to actuate the hand-pressed pneumatic on the glass. Since that was unmodified off-the-shelf part, it was ok.

Dont know if that relates to your problem though.

dlavery 18-01-2005 00:10

Re: Pneumatic's Rules confusion
 
Quote:

Originally Posted by Nitroxextreme
im really confused now
i have a contact at another team and he says that in the past they can use other pnuematics as long as the team pays out of their pocket

Also i heard that one year they allowed a team to use all SMC pneumatics

Rules from prior years DO NOT APPLY to this year! So even if teams were allowed to use SMC products in the past, that is irrelevent as far as this year is concerned.

With regard to the allowed pneumatics for this year, read <R90> and <R91> very carefully.

Quote:

Originally Posted by Kautz
There are no 1/2" bore cylinders on the order sheet only 3/4", 1-1/2" and 2" bore.So you can not use 1/2" bore cylinders of any stroke?

That would appear to be correct. 1/2" bore pistons are not available this year on the Pneumatic Components Order form (nor were they available last year). Under <R90> we can only order pistons identical to those on the order form, which include only 3/4", 1-1/2" and 2" bore pistons. Therefore, 1/2" pistons would not be legal.

Quote:

Originally Posted by jrocket567
It does seem a little more confusing than last year.. the best I can understand it is that you can use as many cylinders, rotary actuators, etc as you want, as long as they are listed on the custom order sheet.. but the thing that is throwing me off is the flow chart.. it states that you can use any pneumatic devices off of previous year's bots.. so if I have a 1/2in bore (they are not on the list this year) on last year's bot, can i take it off and use it this year??

1/2" bore pistons were not legal items last year (they are not listed on page 19 of the 2004 FIRST Pneumatics Manual - only 3/4", 1-1/2" and 2" bore pistons were allowed). Based on that, the flow chart and the rules seem consistent. You could use any legal pistons or valves from last years pneumatics kit (all the elements of the 2004 pneumatics kits are included in this years kit, except we get two double solendoid valves instead of a single and a double, and the Texas Instruments pressure transducer is missing), and they would be permitted under <R91>.

-dave

Steve W 18-01-2005 08:20

Re: Pneumatic's Rules confusion
 
Dave maybe you can find the answer to this question. I asked on the Q&A if you could use 6ft coiled connector hoses that are off the shelf. Now according to the rules they are connectors and off the shelf. They are not storage devices. Last year for some reason they were disallowed. They are the same diameter as the current hose that we receive in the KOP. The safety issue that we are concerned about is better because coiled hose does not flop around on the robot or swing in open air. When I asked the question all that was answered was check the flowchart. Why does FIRST not give us a yes or no answer. There is nothing worse than building and getting to a regional to find out that something is disallowed.

Thanks in advance for any clarification.

dlavery 18-01-2005 10:10

Re: Pneumatic's Rules confusion
 
Quote:

Originally Posted by Steve W
Dave maybe you can find the answer to this question. I asked on the Q&A if you could use 6ft coiled connector hoses that are off the shelf. Now according to the rules they are connectors and off the shelf. They are not storage devices. Last year for some reason they were disallowed. They are the same diameter as the current hose that we receive in the KOP. The safety issue that we are concerned about is better because coiled hose does not flop around on the robot or swing in open air. When I asked the question all that was answered was check the flowchart. Why does FIRST not give us a yes or no answer. There is nothing worse than building and getting to a regional to find out that something is disallowed.

I can't give you an official ruling on the connector hoses, only FIRST can do that. But I will say that with our team I tend to be very conservative when it comes to determining if something is in compliance with the pneumatics rules or not. In general, if it did not come in the pneumatics kit or it is not explicitly (rather than implicitly) permitted under <R90> or <R91>, then we don't use it. We try to keep ourselves out of trouble by not over-interpreting the definitions.

With that in mind, as I read <R90> and note where it says you can use an unlimited number of "connecting fittings" I put the simplist interpretation on that phrase that I can. A fitting is a simple, monolithic piece used to connect two other parts with dissimilar physical interfaces, such as the bag of brass fittings that come with the kit. A connector hose is not a single fitting, it is an assembly of two (or more) fittings and a hose. So let's then go through the flow chart for each of the individual parts of the assembly. Each of the individual end fittings would safely fall through the flow chart, and would seem to be OK to use. But the hose is another matter. It falls through these logic blocks: it is a pneumatic component; it is not an air cylinder; it is not a purchased fitting, valve or purchased air cylinder; and it is not a piston or valve from last years robot. Therefore, the hose itself would be illegal. Double checking with <R90> and <R91>, we see that "tubing" is not explicitly listed as an "unlimited" item. So, in the case of our team (and as mentioned above, we take a very conservative approach to the pneumatics rules), we would say that the connector hose failed the flow chart test and would not use it.

This is my opinion only, which is being provided at no cost and is therefore worth what you have paid for it. Your mileage and interpretation may vary. :)

-dave

Steve W 18-01-2005 10:40

Re: Pneumatic's Rules confusion
 
Dave, thanks for your reply. Even though you say I get what I pay for I believe it to be of more value. When you see me next be sure to collect your $0.02.

:rolleyes:

I guess I don't understand the logic all together. As sold off the shelf the "hose" is sold as a connector hose which I understand from some sides may be seen as stretching (no pun intended) the term. For an safety point I am totally lost as why FIRST wouldn't want someone to use this off the shelf product.

Maybe I will ask the question again to get a yes or no answer rather than "let's see what happens" rule.

Thanks again for your insight.

BillCloyes 18-01-2005 13:45

Re: Pneumatic's Rules confusion
 
I'm not trying to get into a debate on grammar, just clarification on the second half of <R90>:
Quote:

Originally Posted by <R90>
...you may purchase additional air cylinders or rotary actuators, however, they must be identical to those listed on the Pneumatic Components Order form, and obtained from a Bimba or Parker Hannifan distributor.

Does this mean (A) or (B)?

(A):
"...they must be:
- identical to those listed on the Pneumatic Components Order form
- obtained from a Bimba or Parker Hannifan distributor

Or

(B):
"...they must be identical to those:
- listed on the Pneumatic Components Order form
- obtained from a Bimba or Parker Hannifan distributor

At least if i read this correctly...
(A) means that cylinders MUST be Bimba/Parker BRAND (only in sizes listed on the order form) while (B) means the cylinders could be other brands, provided they are otherwise (size/type/style) identical to Bimba/Parker (only in sizes listed on the order form).

I only ask because if we could use other brands (rated the same and visually identical to Bimba ones) that are carried by places like McMaster Carr or MSC teams could order, receive, and implement them MUCH faster.

My experience with FIRST says that (A) is correct, but my common sense says that (B) should be correct.

-Bill
(I know already that it is usually unwise to try to apply common sense to FRC rules :) )

Nitroxextreme 18-01-2005 14:41

Re: Pneumatic's Rules confusion
 
For example, can we use a modified off the shelf gripper? Keep in mind the pneumatic portion is in its original unmodified condition and is a COTS item.


Bah, I'm so confused :confused:

Thanks


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