Leonardo da Vinci designed a catapult with a rotating arm to launch stones or bolts.
Leonardo’s military notebooks contain several designs for projectile machines. His catapult concepts use stored mechanical energy in springs, bent members, or twisted materials and release that energy through a throwing arm. The arm’s rotation could send a projectile toward a target without gunpowder.
These studies formed part of Leonardo’s work as a military engineer in Renaissance Italy. He examined how leverage, tension, and release mechanisms could improve range and repeatability. Some drawings are highly elaborate, but they do not prove that every proposed machine was built.
A catapult differs from Leonardo’s giant crossbow, which launches a projectile with a large bow and string. It also differs from a trebuchet, whose throwing arm is powered primarily by a falling counterweight. Leonardo’s catapult belongs to the older family of mechanical artillery, redesigned through his detailed sketches.