What machine did Leonardo da Vinci design to move itself using coiled springs?

Leonardo da Vinci designed a self-propelled cart powered by coiled springs. The machine is often described as an early predecessor of the automobile because it could move without being pulled by an animal.

Leonardo's drawing shows a three-wheeled vehicle. Two large driving wheels receive power from wound springs, while a smaller front wheel helps guide the cart. A clockwork-like mechanism controlled the release of stored energy, and adjustable parts could set the distance traveled or the route.

The cart was probably intended for theatrical or ceremonial use rather than ordinary transport. It had no internal-combustion engine and was not a modern car. In 2006, a replica built by experts at the Museo Galileo in Florence demonstrated that the design could move, although the original drawing leaves some construction details open to interpretation.