Reduction of Kinetic Friction by Harmonic Vibration

Abstract

The coefficient of kinetic friction between sliding solids is influenced by vibration. This paper treats such a case as a solid body sliding on a surface vibrated sinusoidally in an arbitrary direction. Defining the effective frictional force effective to the motion of a solid body equivalently as a mean value of components of the kinetic frictional force projected in the slide direction, the effective coefficient of kinetic friction is expressed as a function of the velocity ratio V, the velocity of solid body X^^· to the amplitude of vibration velocity Aωsinγ. Some results obtained thus, analytically and also experimentally, are as follows : the effective coefficient of kinetic friction generally reduces at least with a decrease of V by any vibration, though varied in modes. And simultaneously the Coulomb friction comes to behave just like a viscous one. The most effectual direction of vibration to reduce it, is coincidence with that parallel to sliding, that V is near unity.