What wheeled Leonardo da Vinci invention is considered an early programmable machine?

Leonardo da Vinci’s self-propelled cart is considered an early programmable machine.

Leonardo designed the cart around 1478–1480. Its movement came from coiled springs hidden inside the body, while adjustable pegs on the wheels controlled the sequence of motion. This allowed the cart to follow a predetermined path rather than simply roll freely.

The design was probably intended for theatrical performances or court entertainment. It was not an automobile in the modern sense: it carried no engine, fuel tank, steering wheel, or driver. Its springs had to be wound before operation, and the programmable settings determined how the wheels turned.

The cart is sometimes called Leonardo’s robot because a reconstructed version was used in a 2006 demonstration of his mechanical ideas. That label can mislead readers into imagining an electronic machine. The cart was a mechanical automaton, but its programmable control system makes it historically remarkable.