Characterization of light contact in head disk interface with dynamic flying height control

摘要

This paper presents an investigation of the light contact in a head disk interface with dynamic flying height control. The touchdown test is conducted for a dynamic flying height control slider and the response is recorded using AE sensor. The bouncing instability and light contacts are observed during thermal actuated touching down process of the slider. The physics-based simulation is conducted to correlate with the experiments, so as to characterize bouncing instability and the factors affecting bouncing instability. The enhanced spectrogram and HHT approaches are used to extract and characterize the non-stationary characteristics of the weak signal of slider response under light contact. It is found that the light contacts are constituted by a series of intermittent transient impact responses with frequency identical to slider’s pitch mode.