Theoretical and experimental investigations of pre-rolling resistance of a ball on a flat surface were carried out. The cycling displacements of the ball were considered within a range much smaller than the radius of a contact patch. The method of free oscillations of a pendulum supported with two balls on a substrate is proposed for experimental investigations. It is proved that this method allows measurement of a set of parameters of pre-rolling resistance with high sensitivity and precision. The proposed setup has secured pure rolling measurement conditions.

Dynamics of small free swings of a pendulum supported by two spherical balls pre-rolling on a flat basis are considered to investigate the occurrence of micro-slippage at the contact interface between the balls and the flat surface. The basic mechanisms of this micro-slippage are investigated, showing how geometric conditions could initiate and magnify microslippage rather than assuming that these effects are core characteristics in any rolling system. This article also discusses the energy dissipation of a ball slipping on a flat surface at pre-rolling caused by three mechanisms and the conditions enabling the decrease of energy dissipation of the pendulum and the influence of the basis vibrations.

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The development results of a single-point contact system set up as a pendulum to study the laws of rolling resistance to contacting bodies at a distance significantly reduced compared to the elastic contact spot size. The designed device uses a physical pendulum sustained by only one ball on a flat polished surface. The problem of stability of the pendulum swing plane is solved. A phenomenological theory of rolling resistance is described. The surface tension of solids on the contact zone, parameters of the frequency-independent internal friction and the pressure of the adhesion forces are found.