What vehicle did Leonardo da Vinci design with four wheels, steering, and a spring-powered drive system?

Leonardo da Vinci designed a self-propelled cart with four wheels and a spring-powered drive system.

The cart appears in drawings from around 1478 to 1480 and is often described as an early ancestor of the automobile. Two symmetrical leaf springs stored energy, while a geared mechanism transferred that energy to the wheels. Steering could be set in advance through the front axle.

The design may have been intended for theatrical performances or court festivities rather than practical transportation. In 2006, engineers at the Museo Galileo in Florence built a working model based on Leonardo’s surviving drawings.

It is sometimes called a “robot,” but that label can confuse it with Leonardo’s later mechanical knight. The cart was autonomous in its movement, yet it was not an engine-powered car in the modern sense: its energy came from wound springs.