[pfreivald]

This is my point. I'm not trying to rain on anyone's parade, but better to hear it now than to get to competition and be disqualified for safety reasons (so that you have to dismantle your launcher and just be a race-bot for the rest of the tournament).

I did the math at 45 degrees and 2.5 meters and found the initial kinetic energy requirement to be 221 Joules (accounting for reasonable assumptions on energy loss, etc.).

I think that teams who try this method will (a) be disappointed in just how -hard- it is to throw that ball with a robot and (b) will be disqualified from play until they disengage their springs.

That said -- more power to you if you want to try.

Patrick