What device did Leonardo da Vinci design to move under its own power using springs and gears?

Leonardo da Vinci designed a self-propelled cart powered by springs and controlled through gears.

The machine appears in Leonardo’s drawings from the late 15th century. It had two large driving wheels and a smaller front wheel for steering. Coiled springs inside the driving wheels supplied stored energy, while a system of gears regulated the release of that energy and set the cart’s route.

The cart probably had a theatrical or ceremonial purpose rather than serving as a practical road vehicle. It may have been intended to enter a performance space automatically, carrying scenery or a symbolic figure. Because the original machine has not survived, historians rely on Leonardo’s drawings and later reconstructions to interpret its mechanism.

The cart is often called a robot precursor or the world’s first programmable vehicle. Those labels are useful comparisons, but they should not suggest that Leonardo built a modern automobile. The design had no engine, and its movement was limited by stored spring energy and its preset mechanism.