Two cannons on top of the tank fire LEGO spheres. They are made of the special LEGO element that is specifically designed for this purpose. Both cannons are powered by the same EV3 medium motor, which is plugged into port A.
The motor splits its power to both cannons through a 90-degree gear connection. On either side there is a cam mechanism. When the motor spins, the cams slide a rod back and forth through the firing element. When the cam pushes the rod into the forward position, it ejects a sphere from the firing element at high velocity. This is how the turret fires the spheres. The motor continues to rotate the cam, and the rod slides back to make room for another sphere, which reloads the cannon. By simply setting ...
