I want to create an adjustable mounted pneumatic cannon that will shoot volleyballs at variable speeds (5 - 30 mph) to emulate serves and sets, as well as potentially on a downward trajectory for digging (bonus), and perhaps with an adjustable degree of topspin
(double bonus). The standard diameter of a volleyball is about 8.15-8.4 inches. I can piece together the basics of a pneumatic device for launching, and because of the difficulty of finding an 8.x-inch tube, I assume I should utilize a piston-driven design. Any special considerations, best practices, or existing project plans that could help me out? Thanks!
