Pneumatic Air question

I was looking through the game manual and it says we can have two tanks filled to a max of 100 psi but it doesn’t say anything about two separate tanks on the same robot, so if we have two tanks separate from each other can we fill each with 100 psi or can we only fill to 50 psi each. its a stupid question but yeah.

You can have either one or two air tanks. Usually multiple tank are linked together, to provide more actuations of your air cylinders. But there would be nothing wrong with having two separate pneumatic systems (I just can’t think of a good reason why you would want too). Fill your tank(s) to 100 psi, the maximum allowed pressure. There’s no reason to have less than 100 psi…if you want to use less to actuate your air cylinders (and thus get more cycles/less force per cylinder), then use a regulator to reduce the pressure, installing the regulator between your air tanks and the solenoid valves.


Each can be filled to 100 psi. The max pressure is, of course, intended for safety, not just as a limiting factor (although the tanks are rated for much higher).

You might consider joining the two tanks, for the sake of having only one that needs filling, and what I would consider a ‘cleaner’ system, but there are, of course, advantages to having two separate ones as well, such as weight distribution and redundant systems in case of failure. All this to say, good luck! I hope you get your pnuematics working!

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hi 53171A here, we actually chose to not connect our pneumatic reservoirs together as we have multiple pneumatic components that we want to ensure run throughout a match. our pneumatic trigger is on its own reisvior while our transmission and endgame run on a separate reservoir. we made this decision as we expect our trigger system to occasionally use up all the pressure in its reservoir ensuring we can shift gears and initiate our endgame no matter how many discs we shoot.


Thank you i was just wondering this as certain systems need a good amount of psi to work like the expansion and im afraid that we will lose too much if we connect it to the indexer.

You can use multiple regulators in your system to provide different operating pressures to your various air cylinders. Just “T” your air line between the air tanks and solenoid valves and insert a regulator before each solenoid. Then, you can dial up the pressure just enough for your air cylinder to operate your mechanism properly. Through either practice of software, you can track how many times you operate your indexer cylinder(s), as to ensure enough pressure in reserve for your expansion. (and your expander probably doesn’t even need regulated air pressure).


Yeah, our team found that using a flow limiter on the indexer saves enough air that it’s pretty trivial. We haven’t run out of air in a match yet, and we consistently take about 15 shots. We also trigger expansion with pneumatics, but we figure those can use the rest of our air, so they don’t have flow limiters.

the only issue was we designed the indexer terribly with the old linear slides and it had lots of friction, not to mention it was also a double acting piston. this time we are going to try a single acting piston and ditch the linear slides.

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Using standard terminology will help make your comments clear. There’s two devices in the VEX kits to affect the air flow: a “regulator” and an “exhaust flow control valve”.

The regulator reduces the pressure from whatever is in your air tank to a consistent lower pressure to operate the air cylinders at whatever force is required. Regulating the air pressure to a lower value will allow your air supply to last longer.

The exhaust flow control valve is the annoying fitting that VEX provides for the air cylinder, that allows you to slow down the action of the cylinder by adjusting a small screw. Most teams open this valve all the way, or better, just replace the exhaust flow control with a straight fitting (KQ2S04-M5A by SMC - Buy or Repair at Radwell - . Slowing down the cylinder actuation speed does not save any air: the cylinder still uses the same amount of air for a cycle, it just runs slower if the valve is choked down.

More information about pneumatics in a paper I wrote awhile ago: pneumatics information.pdf - Google Drive

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Apologies, I was referring to a flow regulator, but I forgot the name and was just imagining the part in my head. Thanks for the correction!

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