What vehicle did Leonardo da Vinci design with three wheels and a wind-up mechanism?

Leonardo da Vinci designed a self-propelled cart with three wheels and a wind-up mechanism. The machine is widely described as an early programmable or robotic device because stored mechanical energy could make it move without a driver pushing it.

Leonardo’s drawing shows a compact cart powered by coiled springs. The springs were wound before operation, and gears transferred their force to the wheels. Steering could be set in advance, allowing the cart to follow a predetermined path rather than respond to a person during motion.

The design probably had theatrical or ceremonial value rather than serving as a practical road vehicle. It may have been intended for court pageants, where an automatically moving object could create a striking spectacle. The mechanism also demonstrates Leonardo’s interest in automation, gearing, and controlled movement.

The cart is sometimes called Leonardo’s car, but “self-propelled cart” is the clearer historical description. Modern reconstructions have shown that the basic mechanism can work, although the original drawing leaves some construction details open to interpretation.