Hello, I'm an electrical engineering student at Washington State University, and I am attempting to design a beer pong (more properly known as beirut) playing robot. It won't be completely autonomous, as you will still have to tell it when to shoot, and load the balls, etc. Anyway, all of the components necessary to make it are clear to me besides the launching mechanism. What I need is a launching mechanism that will launch the ball varying distances in a reliable manner that is not too large. I've had a few ideas for doing this: something similar to a http://www.youtube.com/watch?v=LBxUjBUdQ5o", or perhaps using compressed air? EDIT: The wheel option looks terribly inaccurate based on all the youtube videos. I'd like to keep the robot relatively small; hopefully it will be less than a few cubic feet. Any suggestions? Thanks! EDIT: I just realized that in implementing a control for the vertical angle of the launcher that I would no longer need it to change it's launch speed.