What type of machine was Leonardo da Vinci’s 1478 design that could move without being pushed?

Leonardo da Vinci’s 1478 design was a self-propelled cart. It used coiled springs to store energy, with the release of that energy turning the wheels and moving the vehicle without an animal pushing or pulling it.

The cart was probably intended for theatrical or ceremonial use rather than transport. A steering mechanism could be set in advance, allowing the cart to follow a predetermined path. This made it more like an automatically moving stage device than a modern car.

The drawing is often described as an early ancestor of the automobile and a precursor to programmable machines. In 2006, engineers built a working replica based on Leonardo’s design and demonstrated that its mechanism could operate. The cart is also sometimes linked to the history of robotics because it could perform a planned movement autonomously.