Which Leonardo da Vinci design is considered an early self-propelled vehicle?

Leonardo da Vinci’s self-propelled cart is considered an early self-propelled vehicle.

Leonardo sketched the cart around 1478–1480. Springs wound inside the mechanism supplied power, while programmed components controlled the rotation of its wheels. The design may have been intended for theatrical performances or court spectacles rather than transportation.

It is often described as a predecessor of the automobile, but that comparison needs care. The cart had no engine, steering system, or practical road-going purpose in the modern sense. Its importance is that it could move without someone continuously pushing or pulling it, using stored mechanical energy and timing mechanisms.

In 2006, an Italian team built a working replica based on Leonardo’s drawings. The reconstruction demonstrated that the mechanism could operate, although details had to be interpreted because the original design is incomplete and some components are not fully explained.