What wind-up vehicle did Leonardo da Vinci design that could move without a person riding it?

Leonardo da Vinci designed a self-propelled cart that could move without a person riding it.

The late-15th-century drawing shows a three-wheeled vehicle powered by coiled springs. As the springs unwound, they transmitted force through gears to the wheels. A steering mechanism was also included, allowing the cart to follow a predetermined path.

The machine is often described as an early ancestor of the automobile or robot, but it was not powered by an engine and was not an automobile in the modern sense. Leonardo may have intended it for theatrical performances or court spectacles, where a vehicle could appear to move mysteriously.

Several reconstructions have demonstrated that the basic mechanism can work. The surviving drawings do not provide every construction detail, so modern replicas must interpret parts of the gearing and spring system.