What machine did Leonardo da Vinci design to move automatically without a driver?

Leonardo da Vinci designed a self-propelled cart to move automatically without a driver.

The cart appears in drawings from around 1478 to 1480. Coiled springs hidden inside its body supplied the stored energy, while mechanisms connected the springs to the wheels. The design could therefore produce movement without an animal pulling it or a person pushing it.

Historians often describe it as an early ancestor of the modern automobile, although it was not powered by an engine. It was probably intended as a theatrical device or stage prop rather than practical transportation. The cart’s steering was also limited: its route could be set in advance through the arrangement of pegs and controls.

A full-scale reconstruction demonstrated that the design could work, though the original drawings leave some details open to interpretation. It should not be confused with Leonardo’s later military vehicle sketches, which used a different concept and purpose.