Designing a "belt + roller" conveyor for balls

[GeeTwo]

Originally Posted by Greg Needel

so here is another question, what diameter rollers do you all like to use? I know that there are minimum diameters for the different thicknesses of polycord, but I have never fell upon a standard roller diameter that seemed to work better than others.

We did something pretty small (about 1") for our 2012 robot. This was our rookie year, limited budget, and we spent most of it on registration and shifters. The diameter was selected so that we got the right speed for one of the motor/gearbox combinations we had (I believe it was a window motor).