What wheeled device did Leonardo da Vinci design to move without a horse or human pushing it?

Leonardo da Vinci designed a self-propelled cart that could move without a horse or person pushing it.

The machine, drawn in the Codex Atlanticus, used coiled springs to store energy. When released, the springs turned the cart’s wheels through a system of gears. A steering mechanism could be set before the cart moved, allowing it to follow a predetermined route rather than being continuously directed by a driver.

The cart was probably intended for theatrical performances or court spectacles, where an apparently moving object would create an impressive effect. It was not an automobile in the modern sense: it had no engine, no occupant’s controls, and only a limited energy supply.

Reconstruction projects have shown that the design can work when built from Leonardo’s drawings, although the exact original purpose remains uncertain. The cart is important because it applies stored mechanical energy and programmed steering to transportation.