What Leonardo da Vinci design is commonly called the first self-propelled cart?

Leonardo da Vinci’s self-propelled cart is commonly described as an early ancestor of the automobile.

Leonardo drew the cart in the late 15th century. Unlike a normal wagon, it was designed to move without an animal pulling it. Coiled springs stored energy inside the frame, while a system of gears transferred that energy to the wheels. Steering could be set in advance, allowing the cart to follow a programmed path.

The cart was probably intended for theatrical effects or court entertainment rather than road transport. It may have been used to create an apparently magical moving object during Renaissance celebrations. Its mechanism was reconstructed in the 20th century, and later versions demonstrated that the basic arrangement could move.

It is sometimes called a robot or an automobile, but those labels need care. The cart was not an engine-powered car in the modern sense, and it could not continuously propel itself. Its stored-spring mechanism makes “self-propelled cart” the clearest name for the design.