Pneumatic Cylinder Length

[billy]

Hey all,
During the R&D stages of our team we were wondering if we could use pnuematic cylinders ordered directly from bimba with stroke length's greater then 12". Or, were we limited intentionally by the pneumatic cylinder order form in the back of the pnuematics handbook? It seems rather strange that we'd be limited to using motors for any kind of linear movements greater than one foot. This could lead for a less robust, more unreliable robot (not too mention harder to design and build). Feedback?
Thanks,
-billy
Co-nerd of team #833, Big Island of Hawaii

[Matt Reiland]

Originally posted by billy
Hey all,
During the R&D stages of our team we were wondering if we could use pnuematic cylinders ordered directly from bimba with stroke length's greater then 12".

Billy, you are intentionally limited to using only the cylinders listed in the back of the pnuematics manual as stated here in the restricted hardware section

Pneumatics/Hydraulics
Air Cylinder-From Custom Cylinder Order Form-up to 3

This is to limit the advantages certain teams might have if they ordered custom cylinders that other teams might not have access to. Also with a limited # of cylinders the chances of having replacements at the regional and the Nationals is much higher.

[ChrisH]

Since we have limited air storage, even a stroke of 1' is pushing it in terms of air consumption. You only have so much volume to work with.

For a 1' stroke 2"diameter cylinder, you would burn through your stored air pretty much on the first use. After that system pressure would drop below 60psi, the next use would be below 30psi and the valves will stop working.

Yes, you do have the onboard compressor but it takes time and power to recharge the system. Not to mention that fact it weighs about 9lbs.

For linear motion greater than a few inches we tend to use cable. It's amazing what you can do with it when you know how. But you'll have to figure that out for yourself.