What self-propelled vehicle did Leonardo da Vinci sketch in the Codex Atlanticus?

Leonardo da Vinci sketched a self-propelled cart in the Codex Atlanticus.

The cart used coiled springs to store energy and transmit motion through gears. Its front wheels could be set to follow a predetermined path, making the machine an early example of programmable mechanical movement rather than a vehicle controlled continuously by a driver.

Leonardo’s drawing dates to the late fifteenth century, and the machine was probably intended for theatrical or ceremonial use. It may have been capable of moving automatically across a stage, carrying scenery or a figure during a court performance.

The cart is sometimes called Leonardo’s automobile, but that label can be misleading. It had no engine, steering wheel, or modern road function. In 2006, researchers and museum staff built a working reconstruction using the drawing as a guide. The reconstruction demonstrated that the spring-powered mechanism could operate when assembled with practical dimensions.