What self-propelled vehicle did Leonardo da Vinci design using springs to power its movement?

Leonardo da Vinci designed a self-propelled cart powered by coiled springs.

The cart appears in Leonardo’s notes from the late 15th century. Its mechanism used wound-up springs inside the vehicle, while a system of gears and cams controlled the rotation of the wheels and the cart’s programmed path. The device may have been intended for theatrical performances, court spectacles, or as a mechanical demonstration rather than transportation.

It was not an automobile in the modern sense. The cart carried no combustion engine, and its stored spring energy could only drive it for a limited distance. Much of the original mechanism had to be reconstructed from Leonardo’s drawings because he did not leave a complete surviving vehicle. In 2006, an Italian team built a working replica, showing that the design could move when assembled according to a plausible interpretation of the sketches.