Rotational sliding contact dynamics in a non-linear cam-follower system as excited by a periodic motion

The rotational sliding contact dynamics of a cam-follower system is investigated using a single degree-of-freedom system given a periodic motion by the cam rotating about a fixed pivot. This mechanical system includes kinematic, dry friction, and contact non-linearities (loss of contact, non-linear contact stiffness, and non-linear damping) as it operates in both sliding contact and no-contact regimes. The Hertzian contact theory is used to calculate the contact stiffness under both line and point contacts. The non-linear formulation is numerically solved to calculate the dynamic motions and forces in time and frequency domains. Alternate damping formulations, including combined viscous-impact damping models, are assessed under impacting conditions, and the results are successfully compared with experimental results as available in the literature. The applicability of the coefficient of restitution model is critically analyzed. The friction and contact non-linearities of the system are investigated in the sliding contact regime. Finally, the kinematic non-linearity is studied in comparison with a linearized model.