A Novel Method of Characterizing Slider Dynamic Motion During Intermittent Head-Disk Contact

Characterization of slider motion induced by contact is becoming a critical aspect of developing advanced head-disc interfaces. While vertical motion induced by contact has been studied, very little is known about down-track motion. We have introduced a new technique where the down-track motion is captured and the dynamics in three dimensions are analyzed. We have applied this technique to measure the position of a slider as it transitions from flying to making full contact with the media surface. We find that slider motion varies considerably with varying levels of interference and that motion in all three directions is considerable. Spectral decomposition is used to identify the vibration modes that are excited in each direction, and we find that for most of the test velocities, vertical modes give rise to motion in the two orthogonal directions. In addition, we present a depiction of the vertical, down-track, and off-track position changes by plotting the position of the slider in real space coordinates to help visualize more completely the slider trajectory. Analysis of motion identifies that at some levels of interference, a majority of motion is repeatable, but that non-repeatable components increase with the amount of interference. Additionally, down-track motion is the only component whose magnitude increases monotonically with increasing interference.