A nonlinear dynamics theory for modeling slider air bearing in hard disk drives

A nonlinear dynamics theory is presented for modeling air bearing slider systems. The nonlinear dynamic coefficients are acquired by fitting the database of the discrete linear dynamic coefficients. The linear dynamic coefficients for an air bearing slider around steady flying state are calculated by using a Reynolds-equation-based perturbation method. A nonlinear analysis shows that the natural frequencies of the system decrease with the increase of slider vibration amplitude, and that the softening feature of the system bends the resonance to lower frequency and complicates the system vibrations. The analysis correlates with experimental results. (C) 2000 American Institute of Physics. [S0021- 8979(00)84508-9].