What vehicle did Leonardo da Vinci design to move under its own power using wound springs?

Leonardo da Vinci designed a self-propelled cart powered by wound springs and arranged to move without being pushed.

The cart appears in drawings from around 1478 to 1480. Its mechanism used coiled leaf springs as a source of stored energy. Transmission components, including gears, transferred that energy to the wheels. Steering could be set in advance, allowing the cart to follow a predetermined path rather than being directly driven.

The device may have been intended for theatrical performances or court ceremonies. It was not an automobile in the modern sense: it carried no engine, had limited stored energy, and could not respond freely to changing conditions. Its importance lies in the mechanical principles it combined.

A 2006 reconstruction by the Institute and Museum of the History of Science in Florence demonstrated that the design could function when built accurately. Some modern accounts call it a robot car, but “self-propelled cart” is the clearer historical description.