Usign a 2-1/2 bore, 24" stroke pneumatic cylinder.

[hrench]

Originally Posted by DanielPlotas

If you use constant force springs in line with your cylinder, you can use a smaller diameter cylinder.

This constant-force spring thing seems like a good idea, but it means that it takes more pressure (equals force) to extend your rod initially. Which means it uses lots of your stored air reaching up for the bar.

I wonder if it would be better to actually put a pressure regulator between the extension-end of the air cylinder and the air solenoid valve and just extend at say 5-psi? If you can still reach up very fast but not actually pressurize the extending side of the air system to a very high number, you'll save all of that stored pressure in your tanks for the lifting-retracting stage.

We built a robot-lifting cylinder in our prototyping at the start of build--used a 2" dia--which should've been able to lift 176 lbs, but with a 120lb robot, battery, bumpers and the added friction of dragging the bumper up the wall, it didn't move very well at 60 psi and was very slow after the air in the storage tanks was used up.

I hope you can make it work. good luck.

Also note,

I know these equations are easy, but if you need a quick-reference for how much force each bimba-sized cylinder makes at 60 psi for pushing and pulling, I've created this easy chart.
https://docs.google.com/spreadsheets...it?usp=sharing