What was the name of Leonardo da Vinci's spring-powered vehicle often called the first self-propelled cart?

Leonardo da Vinci's spring-powered vehicle is commonly called a self-propelled cart.

The cart was designed to move without being pushed or pulled by an animal. Coiled springs stored energy, while a system of gears controlled the release of that energy to the wheels. Steering could be set in advance, allowing the cart to follow a programmed path rather than being driven continuously by a person.

The design is associated with Leonardo's work in the late 15th century and is often described as an early automobile or robot. A reconstruction made for the 2006 Leonardo exhibition at the Museo Galileo in Florence showed that the mechanism could operate when built according to the surviving drawings.

It was not a car in the modern sense: it carried no engine, fuel system, brakes, or passenger cabin. Its importance lies in programmable mechanical motion. The same principle also explains why it is sometimes connected with Leonardo's mechanical automata, including a later mechanical lion.