What wheeled machine did Leonardo da Vinci design with a wind-up mechanism for moving without a driver?

Leonardo da Vinci’s driverless wheeled machine is known as the self-propelled cart.

Leonardo designed the cart around 1478–1480. Springs wound inside the vehicle supplied energy, while a programmable steering system used shaped blocks to determine its path. The mechanism could make the cart move forward without a person sitting inside it to push or steer it.

The cart was probably intended for theatrical or ceremonial use rather than transport. Renaissance court performances often used mechanical effects, and a vehicle that appeared to move by itself would have been an impressive stage device.

The design is sometimes called the world’s first robot or automobile, but those labels need qualification. It was a manually wound mechanical vehicle and had no combustion engine. A full-scale reconstruction was demonstrated in 2006 at the Florence Institute and Museum of the History of Science, now the Museo Galileo.