http://www.youtube.com/watch?v=8ZW4NQXxDCY&feature=youtu.be
nice vid since im on ur team;) 
It will work… But the question is how efficient it is?
Some things you must know abt pneumatics:
You need a compressor - tanks - pistons = extra mass
Pistons are also slow when compared to motors
A small leak can surely cost you the match
Solenoids, pneumatic tubings = extra mess (especially if shooter is at top)