Leonardo da Vinci designed an odometer using a wheel and a gear mechanism to measure how far a vehicle traveled. An odometer records distance by counting wheel rotations and converting them into a travel measurement.
Leonardo’s version was intended for surveying and mapping. As a cart moved, its wheel would turn, driving gears that released or counted small objects at set intervals. The number of objects collected could then indicate the distance covered.
The device belongs to a broader group of Renaissance measuring instruments in Leonardo’s notebooks. It was not an electronic instrument and did not display a number on a dial like a modern car odometer.
The word odometer comes from Greek roots connected with road and measure. Ancient engineers had already developed distance-measuring devices, so Leonardo’s importance lies in his particular mechanical design and its clear connection to practical surveying.