Leonardo da Vinci designed an odometer with a rotating wheel to measure distance.
His concept used a wheel that turned as a vehicle moved. A gear mechanism transferred the wheel’s motion to counting components, allowing the device to record the distance traveled. The machine was intended for surveying and mapping rather than for measuring speed.
Leonardo’s odometer belongs to his broader study of mechanical measurement. Accurate distance data was valuable for military engineering, road planning, mapmaking, and construction. His drawings show how a simple repeated motion could be converted into a numerical record.
An odometer is different from a speedometer. An odometer records total distance, while a speedometer indicates how fast something is moving at a particular moment. Leonardo’s proposal is also separate from the ancient Greek odometer traditionally associated with measuring journeys by counting wheel rotations.