Hello Everyone, First time posting on this forum and looking forward to see what you guys can teach me! I am working on a program for a Raspberry Pi as a controller for a mechanical rotary and need some help from you physics enthusiast out there. Looking for some insight on the calculations that I should consider for calibrating the spread and "swath" of a rotary broadcast spreader. The spreader will have a similar build to that of a lawn broadcast spreader for fertilizers. If your not familiar, a close comparison would be the "Scotts Turf Builder Edge Guard Mini Broadcast Spreader". This spreader will be stationary with heights ranging from 1 - 30 feet off the ground and will have an electric motor with variable speeds. From my point of view, I think I will need to account for the weight/dimensions of what is being spread (considering something like wood pellets or granular rocks sock), radius of the chamber the widget falls into, rotation of the spin, angle of the spreader, period of time the widget is in the chamber and spun before release, and of course the speed at which the spreader spins. Is there any other major object/formulas I need to account for to achieve a decent calculation (>=85% confidence interval) of what I can expect given the widgets I decide to use and the speed at which the spreader spins? I don't have a problem with my numbers considering a vertical/catapult type launch of the widgets, but I'm trying to achieve the spread/single-motor/gravity-feed benefits of the spinning the mechanism horizontally with no more than 20 degrees of vertical play. I'm aiming for distances of 20 ft+ peak and a width of 10 ft min at the half way mark. Also any easier alternative ideas to getting the spread I need would be great as well. I have to admit that I still have much to learn about physics so making formulas/concepts amateur proof would be nice.