What type of vehicle did Leonardo da Vinci design with a conical gear system to move without being pushed?

Leonardo da Vinci designed a self-propelled cart powered by coiled springs and controlled by a gear system.

The cart appears in drawings from the late fifteenth century. Its two large driving wheels were connected to mechanisms that could store energy in leaf springs. When released, the springs turned the wheels, allowing the cart to move without an animal pulling it or a person pushing it. A steering mechanism could also be set in advance through programmable blocks.

The device is often called Leonardo’s automobile or robot, but those labels can cause confusion. It was not powered by an engine in the modern sense, and it was not intended for carrying passengers over roads. The design was probably made for theatrical performances or court celebrations, where a moving object could create a striking stage effect.

A modern reconstruction built for a 2006 exhibition showed that the mechanism could work. The cart is historically important because its spring drive and preset steering resemble early forms of autonomous motion, even though it was a compact mechanical machine rather than a modern car.