ABSTRACT
Kinetic friction is just one of the branches of a remarkably large, interdisciplinary, and far-reaching tree that the authors might call the study of Friction. Da Vinci was performing multiple experiments, which are similar to those traditionally used in the school's physics like blocks pulled by heavy objects through a rope and pulley system and blocks on inclined plans, and he was also studying various methods for reducing friction like ball bearings and lubrications. The varying stiffness of contact ‘springs’, mimicking the asperity contacts, became a typical characteristic of RS modeling approaches, that makes also the concept of rate- and state-dependent friction indistinguishable between static and kinetic friction. Moreover, the interaction of asperities and their kinetics have sometimes also been linked to those of the bristles of a brush. For basics and details on the Lagrangian mechanics, also on the Rayleigh dissipation function, the comprehensive treatment in is recommended.
