Analysis of Bouncing Vibration and Complete Tracking Condition of a Single-Degree-of-Freedom Contact Head Slider on a Harmonic Wavy Disk Surface

Extended study of general characteristics of bouncing vibration of a contact recording head slider is carried out for a single–degree–of–freedom slider model bouncing on a harmonic wavy disk surface with linear stiffness and damping. The relation between bounce height and waviness frequency and the roll of top contact point necessary for stable bouncing vibration are discussed. Since the dynamic contact force increases to ten times the static head load even when the bounce height is only one nanometer, the importance of complete tracking without separation is stressed. Then the complete tracking conditions of disk surface waviness under ten nanometer bounce height disturbances are calculated for various design parameter values, including the phase of the waviness. It is also shown that a collision model can predict almost the same complete tracking boundaries as the elastic contact model.