Updates on the rocking phenomenon
Common models for wheel/rail contact typically start from a prescribed creepage or imposed contact force. This excludes the dynamical interaction between the two where each one responds to the other. This paper introduces a different approach where friction is related to the local deformation in and around the contact patch. This leads to forward and angular velocities that are oscillating with opposite phase, leading to the so-called rocking phenomenon. It is shown how the oscillation frequency depends on materials, geometry and normal load, and an experiment is proposed for validating this theory.