Leonardo da Vinci designed a spring catapult to hurl stones with a spring-powered arm.
His military-engineering studies included catapults that stored energy in bent or twisted materials before releasing it through a throwing arm. In a spring-powered version, mechanical springs supplied the force needed to launch a projectile. Leonardo’s drawings show his effort to improve range, control, and the speed with which a weapon could be reset.
Catapults were ancient weapons long before Leonardo. Greek, Roman, and medieval engineers used several forms, including torsion engines and traction devices. Leonardo’s contribution was part of a Renaissance search for improved mechanisms rather than the invention of artillery itself.
The design is sometimes confused with a trebuchet, which uses a counterweight or a manually pulled beam. A spring catapult stores energy elastically, making its operating principle distinct. As with many notebook machines, surviving drawings do not establish that Leonardo’s exact model was built or tested.