Leonardo da Vinci’s self-propelled cart was a spring-powered vehicle designed to move without a person or animal pushing it.
The cart used coiled springs to store energy, much like the mechanisms in Renaissance clocks. Gears controlled the release of that energy, while a steering system allowed the vehicle to follow a predetermined path. The surviving drawing is associated with Leonardo’s studies of theatrical machinery and mechanical motion.
It is often described as a precursor to the automobile because it carried itself forward under stored mechanical power. However, it was not an automobile in the modern sense: it had no engine, fuel system, or means of continuous propulsion.
The cart’s exact operation was reconstructed from Leonardo’s drawings rather than from a surviving original machine. In 2006, an Italian team built a working replica for an exhibition at the Museo Galileo in Florence, helping demonstrate how the spring-and-gear mechanism may have functioned.