Leonardo da Vinci designed an odometer that connected wheel rotation with the distance traveled.
His concept used a cart wheel linked to a mechanism that counted rotations. Each turn advanced a series of gears or indicators, allowing the device to record the distance covered. Leonardo’s design is one of the famous historical examples of an odometer based on mechanical counting.
The principle depends on wheel circumference: if the wheel size is known, the number of complete rotations can be converted into a distance. This approach remains fundamental to many mechanical distance-measuring systems, even though modern vehicles commonly use electronic sensors.
An odometer measures distance, not speed. A speedometer measures how fast something is moving, while an altimeter measures height. Leonardo’s device is also distinct from a pedometer, which counts a person’s steps.