Tennis Ball Cannon
I’ve shot several potato guns. Some were the PVC / hairspray / BBQ lighter type. One was welded stainless steel, powered by compressed air with an solenoid valve for firing. I’ve wanted to build my own pnumatic cannon for years. Ammunition will be tennis balls rather than potatoes and the cannon will be breach rather than muzzle loaded. Electric solenoids will deliver the air to fire the ball as well as open and close the breach using an air cyclinder. With a big air tank and ball feed, the cannon will be capable of automatic firing.
For this project I considered using 555 timers to control the valve timing. Instead decided to use an Arduino which will initially be more complex, but will allow easier tuning of the valve timing and a variety of firing modes. I will go further into the electronics in a future post.
The image above is my drawing of the relay / transistor board that will allow the Arduino to control the solenoid valves. Below are some CAD models. The air cylinder that will close the breach is on the left with the valve that admits the firing air above it.
