Fundamental Study on Rolling Friction in the Region of Micro - Displacement (1st Report)

Development of Forced Type Testing Apparatus for Rolling Friction

Abstract

A testing apparatus having a similar structure to a mechanical stage was designed to study rolling friction acting between a roller and a steel rail. This apparatus equips a pair of voice-coil motors. These linear motors which are applied to ultra-precision positioning mechanisms can control tangential force finely. When the roller is placed on a wavy surface, it is stable at the bottom of the wave due to its minimum potential energy. So it is possible to estimate the motive rolling friction by measuring two forces. One is a driving force which causes the roller to start a rolling. Another is a critical driving force for the transition to steady rolling. Furthermore this motive rolling friction coincides with a steady rolling friction.