Leonardo da Vinci designed an odometer with a wheel and gear system to record distance.
His cart-like measuring device was intended to count the distance traveled as its wheel turned. A sequence of gears transferred the wheel’s rotation to a display or container, allowing the machine to register progress in measured intervals. Leonardo’s design was part of his broader interest in surveying, mapping, military engineering, and mechanical automation.
An odometer measures distance traveled, so it is different from an odograph, which can record a route or trace movement, and from a speedometer, which measures speed. Historical distance-measuring devices existed before Leonardo, but his drawings show a clear mechanical approach using linked rotations and counting mechanisms.
Leonardo did not create the modern automobile odometer. His invention was a manually moved surveying machine, probably intended for roads or land measurement. The principle remains familiar: determine distance by counting wheel revolutions and multiplying by the wheel’s circumference.