What was Leonardo da Vinci’s self-propelled cart designed to use instead of an animal or human driver?

Leonardo da Vinci’s self-propelled cart was designed to move using a clockwork mechanism instead of an animal or human driver.

Drawn around 1478–1480, the cart used coiled springs to store energy. When released, the springs drove the wheels through a system of gears. A programmable steering system, controlled by blocks placed on a small control bar, could make the cart follow a predetermined path. This feature has led many historians and engineers to describe it as an early programmable machine.

The cart was probably intended for theatrical performances or court spectacles. It was not a practical automobile for transporting people, and Leonardo did not use an internal-combustion engine. The design also included a mechanism that helped keep the wheels moving at a controlled rate.

A modern reconstruction built for a 2006 television program showed that the cart could function. Its importance lies in combining stored mechanical energy, gearing, and programmable movement in one compact design.