Ball launchers

I've been playing with packaging a plunger style ball launcher on top of an andymark kitbot chassis and the cad is available through dropbox. The model is really only meant to show the geometry of the mechanism and I would encourage others to open up the model in inventor to have a look and try some modeling (found here, totally legit: http://www.autodesk.com/education/free-software).

With the aid of some back of the envelope calculations for the arrangement shown, the launch angle is currently too low (about 55 degrees) for shooting over the truss, but ok for the goal.

Starting position


concept sketch



The calculations are for the shot distance given angle and the minimum height above the truss. I calculated 7.5m (24ft) which is longer than a fields section's width (18ft), but diagonal passes could be possible.