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Unread 10-03-2014, 09:18
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Electrical/Programming Mentor
FRC #2177 (The Robettes)
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Re: Pre-charing pneumatic air tank

Quote:
Originally Posted by Tem1514 Mentor View Post
The INTENT of the rule is SAFETY.
I guess you missed the Ka-BOOM at GTRW when an air tank was turned into little flying pieces of sharp plastic. Even the crickets went silent.

Do what other teams do and have two compressors, one on the bot and then a standalone. BUT only use ONE compressor at a time that is controlled by the cRIO.
I'll remind you of R79 - "Compressed air on the ROBOT must be provided by one and only one compressor." That does not say "use only one compressor at a time". It says all air must come from only one compressor - if you precharge with an off board compressor then use an on board one during the match, you are violating this rule.

Quote:
Originally Posted by mikets View Post
I still don't understand the intention of the rule. We are thinking of using the same model compressor as the one used in competition. So it is not a more powerful shop compressor. Also, we will be wiring in the same pressure limiting switch and the same Spike as used in the system. The only difference is there is no cRIO. The limit switch directly controls the FWD input of the spike so when the pressure is reaching the limit PSI, it opens the circuit and the Spike will shut down the current to the compressor.
Mikets - The intent of the rule is safety. Any time you use a compressor at competition, it needs to happen under the control of the robot. In your proposed setup here, you're missing the ability to stop the compressor via the e-stop (something that is pretty important and found in all sorts of industrial applications) or to control it via enable/disable. R78 lays out the required pneumatic components for a minimal system, R80 clearly states that the compressor must be powered and controlled by the robot, and R88 clearly states that the cRio must respond to the pressure switch appropriately. There is no wiggle room here.
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