Leonardo da Vinci’s self-propelled cart was designed to move itself without a person or animal pushing it.
Leonardo sketched the cart around 1478 to 1480. It used tightly wound springs to store mechanical energy, much like the springs in a clock. When released, the stored energy turned the wheels through a system of gears.
The cart also included a steering mechanism. One important feature was a programmable control system using shaped blocks, allowing the path to be set in advance. This has led some historians to describe it as an early robot or an ancestor of programmable machines.
The cart’s exact purpose remains uncertain. It may have been intended for theatrical effects, court entertainment, or ceremonial use rather than transportation. A reconstruction built in 2006 demonstrated that the basic mechanism could work, although reconstructions necessarily interpret incomplete historical evidence.