What self-propelled vehicle did Leonardo da Vinci design for stage performances?

Leonardo da Vinci designed a self-propelled cart for stage performances.

The cart appears in drawings from around 1478 to 1480 and is powered by coiled springs hidden inside its body. As the springs unwind, gears transfer motion to the wheels. Steering could be controlled through a programmable mechanism, allowing the cart to follow a predetermined path rather than simply rolling freely.

Leonardo probably intended the device as theatrical machinery for court celebrations. It could move across a performance space and reveal a figure or decoration, creating a dramatic effect for spectators. Because no complete original survives, historians reconstruct its mechanism from Leonardo’s sketches.

The cart is often called a robot or automobile in popular accounts, but those labels can be misleading. It had no engine, computer, or independent decision-making ability. Its significance lies in combining stored mechanical energy, gearing, and programmable motion several centuries before motor vehicles became practical.