What name is commonly given to Leonardo da Vinci’s spring-powered vehicle design?

Leonardo da Vinci’s spring-powered vehicle design is commonly called a self-propelled cart.

The cart appears in drawings from the late 15th century and was intended to move without being pushed by a person or pulled by an animal. Coiled springs stored mechanical energy, while a system of gears controlled the release of that energy.

The vehicle was probably designed for theatrical or ceremonial use, such as creating a dramatic moving effect at a court event. It was not powered by an engine in the modern sense, and it could travel only a limited distance.

The cart is sometimes described as an early automobile, but that wording can be misleading. It had no internal-combustion engine and was not designed for ordinary road transport. Reconstructions have shown that a working version is possible when based on Leonardo’s surviving drawings.