What Leonardo da Vinci machine used a coiled spring to move without a horse?

Leonardo da Vinci designed a self-propelled cart powered by coiled springs rather than a horse.

The machine, usually dated to about 1478–1480, used wound springs inside its front drums to store mechanical energy. A system of gears transferred that energy to the wheels, while a programmable steering mechanism could make the cart follow a predetermined path. The arrangement resembles an early mechanical vehicle or theatrical automaton.

Leonardo may have intended the cart for court spectacles, stage effects, or ceremonial displays rather than transport. It had no engine and could not run indefinitely: its springs had to be wound before operation. A full-scale reconstruction made for a 2006 television program demonstrated that the basic mechanism could work. The vehicle is sometimes called the world’s first robot or car, but those labels are modern shorthand; historically, it was an ingenious spring-driven cart design.