Characterization of nonlinear, non-stationary, nano-scale surfing contact dynamics of TFC slider utilizing high order spectra detection

In this paper, the high order spectra approach is used to determine the surfing contact dynamics signatures of thermal flight control (TFC) air bearing slider in hard disk drives. Detection and identification of TFC slider surfing contact using LDV signal and higher order spectra analysis is presented. The method has been tested by using varied surfing contact cases for a TFC slider under different load conditions. Experimental signals are analyzed and it is demonstrated that high order spectra has superiority in the distinctive and accurate detection of slight surfing contacts. It is shown that the high order spectra method essentially has better detection performance than conventional spectrum method for non-linear and non-stationary dynamics of slider, and it offers more information about the complex system dynamics such as the phase and mode interactions.