What self-propelled vehicle did Leonardo da Vinci design that is often called an early automobile?

Leonardo da Vinci designed a self-propelled cart that is often described as an early automobile.

The machine appears in drawings from the late fifteenth century. Instead of using an engine, it stored energy in two large leaf springs. When released, those springs drove the cart through a system of gears. A steering mechanism could be set in advance, allowing the vehicle to follow a predetermined path rather than being continuously controlled by a driver.

The cart was probably intended for theatrical or ceremonial use, possibly to create a dramatic moving effect at a court event. It was not a road automobile in the modern sense: it carried no internal-combustion engine, and its range and control would have been limited.

A reconstruction displayed at the 2006 Florence exhibition of Leonardo’s machines demonstrated that the mechanism could work when built according to the surviving drawings. The design is therefore important as an early practical example of stored mechanical energy driving a vehicle.