Last year we saved a ton of money by using a good bit of square tubing for the frame of our robot, square tubing is a lot cheaper then C channel. We get to use so much raw material that the cost should go down in certain places. - Derrick Maust [more]
Rebound Rumble ballistic trajectory with air friction drag and Magnus Effect (backspin/topspin lift/dive). For students interested in the physics, math, and computer simulation aspects of this problem. Free-body force diagram, derivation of differential equations of motion, and C pseudo-code for trapezoidal numerical integration.