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A new theory on pure pre-rolling resistance through pendulum oscillations

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.