Leonardo da Vinci designed a tribometer to compare friction between surfaces.
A tribometer is an instrument used to study friction, wear, or lubrication. Leonardo’s apparatus applied a known load to a surface and used the resulting movement or resistance to compare how easily one arrangement slid against another.
His notes show an important early attempt to treat friction as a measurable mechanical phenomenon. Leonardo recognized that the force needed to move an object depended on factors such as load and the nature of the contacting surfaces.
The term tribometer is modern, and Leonardo did not use modern laboratory terminology. However, historians identify his friction-testing apparatus as an early tribometer. It should not be confused with a dynamometer, which measures force more generally.