What Leonardo da Vinci transport design moved itself using wound springs?

Leonardo da Vinci’s spring-powered transport design is called the self-propelled cart.

Leonardo drew the machine around 1478 to 1480. The cart used coiled springs to store energy, much like a large mechanical toy. When released, the springs drove the wheels through a system of gears. A programmable steering mechanism could guide the cart along a predetermined path.

The design is often described as an ancestor of the automobile, but it did not use an engine or fuel. Its stored mechanical energy gave it limited movement, and the surviving drawing does not provide every construction detail. The cart may have been intended for theatrical performances or court celebrations rather than everyday transport.

A reconstruction displayed at the 2006 Florence science museum confirmed that the mechanism could move when built according to Leonardo’s plan. The cart is therefore significant as an early self-moving vehicle concept, while remaining very different from a modern car with an engine, brakes, and continuous steering control.