What did Leonardo da Vinci design to move by itself using clockwork?

Leonardo da Vinci designed a self-propelled cart powered by clockwork mechanisms.

The cart appears in Leonardo’s Codex Atlanticus and is usually dated to the late 15th century. Springs stored energy inside the machine, while gears transferred that energy to the wheels. Adjustable cams could determine how far the cart travelled and how it turned.

The device may have been intended for theatrical use rather than transportation. It could move across a stage without a person visibly pushing it, making it a striking special effect for court performances. Some reconstructions have shown that the mechanism can operate when built according to the surviving drawings.

The cart is often described as an early automobile, but that label can mislead. It had no engine, steering wheel, or passenger compartment. Its importance lies in its programmable mechanical motion and in Leonardo’s use of springs, gears, and cams to create an autonomous machine.