What self-propelled vehicle did Leonardo da Vinci design with clockwork-like mechanisms?

Leonardo da Vinci designed a self-propelled cart powered by clockwork-like mechanisms.

The vehicle appears in drawings from the late 15th century and is often described as an early ancestor of the automobile. Springs stored energy, while a system of gears transferred that energy to the wheels. Programmable control elements, comparable to cams, could determine the cart’s route and make it move through a planned sequence.

The cart was probably intended for theatrical or ceremonial use rather than transport. Some historians connect it with court entertainments at the Milanese court, where mechanical spectacles were popular. Leonardo’s surviving drawings do not provide every construction detail, so modern reconstructions have been important for testing how the mechanism might have worked.

It is commonly called a robot or automobile, but it had no engine in the modern sense. Its motion came from stored spring energy.