Does exhaust air need to be muffled, or can it just be opened to the atmosphere?
just opened to the envirement.
feeding it back in might pose problems, but if u put a compresser on the robot, just vent it
Either way the easist thing to do is to vent it.
(you could alwasy loop it back into your system so that minimium ammount of air is lost if you are not using a compressor)
The system won’t work this way - air moves from higher pressure to lower pressure. If you vent the exhaust to a storage device, it will be at a slightly lower pressure than the cylinder you just used. If you keep venting more and more air, eventually you will equalize the system pressures and nothing will move.
Unless you want to work another downstream cylinder at a lower pressure, and set up an elaborate system of check valves and pressure reliefs, you can’t get more work out of the exhaust.
Let them vent, and don’t even worry about putting fittings on - save the weight. 
After I posted, i realized that you would need check valves, therefore making it much more complicated (and i do believe unusable since i don’t think you can use check valves on the robot)
If you use the fittings with the little screw adjuster (flow control) you can affect the speed that a piston moves (somewhat) this can help in a situation where you want to slow down the piston if it is lifting something heavy while pushing but you want it to come back slower when pulling. Sorry don’t have a good picture handy. Also not sure the flow control fittings are part of the kit this year.
Biff
I am shocked and dismayed by all of these suggestions to vent
exhaust air to the atmosphere! Don’t you guys and gals know
your environmental regulations? You have to recycle this exhaust
air properly as hazardous waste…
Eugene
Agreed! Everybody knows that you get nauseated if you breathe too much of this stuff in too fast.
(Sorry, couldn’t resist.)
The only thing the sintered mufflers do is quiet the exhaust air some and help keep dirt out of the valve when it’s not exhausting. The dirt factor isn’t such a big concern in the enviroment where FIRST robots are as it would be where the valves are used out in some industrial applications.
I think you need to have a car muffler on their that makes it hum… lol
If regular air is being inserted through the compressor into the tubing, stored and used to move a piston, then released out into the atmosphere, isn’t it just the same air it was when it went in? Why would it be considered hazardous waste?
And I would like to know if team could and would post a diagram of a simple closed air system (or explain in Great detail) to feed compressed air back into a system instead of releasing it and losing air pressure. Our team never really got around to creating a sub pneumatics team. It’s always been just Electrical, Programming, and Mechanical.
I would assume a second lower pressure system would be needed to feed into, but I don’t know how to feed it back into the higher pressure system, or to keep them unequalized, or the effect a 60 - 40 PSI co-system would have on power to the cylinders we are using.
I had trouble finding anything helpful on the internet, although I’m a terrible, but persistant searcher.
Pretty sure we’re not going to be venting the air into the system - we were just wondering if we needed to put any mufflers on the valve… Guess not