I did not design the original Support Gunner, it was done by Micah, also known as CATpit contractor on http://thenxtstep.blogspot.com blog (http://thenxtstep.blogspot.com.au/2007/12/support-gunner.html). I have just added controls for moving the gun up and down using a sound sensor, and rotating the gun via a touch sensor.
This way I can control what I want to shoot - which is mostly Lego figurines :-)