Quote:
Originally Posted by Mageofdancingdr
what if you create a shifting mechanism between pneumatics and CINs, so you can push with pneumatics engaged and drive with the CIM motors?
also, when I was thinking of power, I was thinking of the power during the time before the tanks ran out, which I think would be more powerful than the CIMs during the same time period (how would I do the math to find out though, where is the power rating for a cylinder?)
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It is possible to do what you've described, but it is probably more cost and weight effective to use a shifter transmission because you will be traction limited.
And... what is this? A student who wants to know how to the math?! I'm confused and terrified right now

more on this later...
Quote:
Originally Posted by Ether
The power you can get from pneumatics on FRC is limited not by the cylinder, but by the solenoid ⅛” NPT port diameter and maximum Cv of 0.32
You can use solenoids in parallel to mitigate this somewhat, but other fittings and line losses limit what you can achieve.
A CIM has a maximum power of 337 watts, but this can be sustained only briefly, not the entire match.
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What Ether said, though IIRC it's the internal valve diameter that severely limits flow through a solenoid, and I can't remember the dimensions off-hand. And yes, a CIM cannot be run full-power for an entire match (probably not more than once, anyway), though 4 Cims could likely be run at an average of 1/4 power (maybe more?) for a whole match. This would be an interesting experiment.
Back to the math...
I assume you are referring to using pneumatics in a reciprocating-piston setup, in which case you can calculate a
theoretical power output using ideal Otto cycle calculations, where your volume values are computed by geometry, and your pressure values are determined from approximate flow rates through the supplying solenoid(s).
Edit: it won't be
exactly like an Otto-cycle calculation, but it will be close, you'll be integrating work done in a PV chart.