What self-moving vehicle did Leonardo da Vinci design without an animal or human pulling it?

Leonardo da Vinci designed a self-propelled cart that could move without an animal or person pulling it. The spring-powered vehicle is often described as an ancestor of the modern automobile and was probably intended for theatrical or ceremonial use rather than transportation.

The cart used coiled springs to store energy. When released, the springs drove the wheels through a system of gears, while mechanisms helped control the cart’s path. Leonardo’s drawings suggest that the vehicle could be set to travel along a predetermined route.

The design was rediscovered in Leonardo’s Codex Atlanticus and reconstructed in the twentieth century. In 2006, a working model was built at the Museo Nazionale della Scienza e della Tecnologia in Milan. The cart is sometimes called a robot because it could perform a programmed movement, but it was not a humanoid robot. Its importance is that it combined stored mechanical energy, gearing, and automatic motion centuries before powered road vehicles became practical.