What kind of vehicle did Leonardo da Vinci sketch with a spring-powered mechanism in the Codex Atlanticus?

Leonardo da Vinci sketched a self-propelled cart with a spring-powered mechanism in the Codex Atlanticus.

The cart is generally described as an early ancestor of the automobile. Two large leaf springs stored mechanical energy, while a system of gears transferred that energy to the wheels. The steering arrangement appears to have been set before the vehicle moved, so the cart was not designed for modern, freely adjustable driving.

Leonardo’s drawing dates from around 1478 to 1480. The machine may have been intended for theatrical use, such as carrying scenery or creating a surprising moving effect at a court event, rather than for transportation over public roads.

It is sometimes called Leonardo’s automobile, but that label can mislead. The cart had no internal-combustion engine, battery, or steam engine. Its motion came from wound springs, making “self-propelled cart” the more precise description. A full-scale working reconstruction was displayed in Italy in 2006.