What machine did Leonardo da Vinci design to move automatically without a person pushing it?

Leonardo da Vinci designed a self-propelled cart that could move without a person pushing it.

The cart used springs as its source of stored energy. Cogs and mechanisms transferred that energy to the wheels, while a programmable control system based on pegs helped determine the cart’s movement. The design is often regarded as an early example of a programmable machine.

Leonardo likely created the cart around 1478–1480, possibly for theatrical performances or court spectacles. It was not powered by an engine in the modern sense; instead, its wound springs gradually released mechanical energy. The cart’s ability to move automatically made it a striking Renaissance demonstration of engineering.

The original machine has not survived, so modern reconstructions rely on Leonardo’s drawings and notes. In 2006, engineers at the Institute and Museum of the History of Science in Florence built a working reconstruction. The cart is sometimes linked to Leonardo’s robot, but it is a separate invention.