Loading Velocity Effect in the Load/Unload Systems With Multiple Flying Height States

Abstract

The effect of the loading velocity on the loading process in the computer hard disk drive air slider system with multiple flying height states was studied numerically. The results of the static analysis were compared with the dynamic loading trajectories. The air lubrication problem was solved using the finite-element method. The static flying height states for variable suspension forces were considered as solution branches and were found by using a numerical continuation method. The dynamic loading trajectory was obtained iteratively by applying the Newmark method for the slider position and an implicit scheme for the air film pressure. Close agreement was found between the solution branches and the trajectories of dynamic loading with a velocity of 5 mm/s. At the higher velocities, the unstable negative pitching motion and the slider-disk contact at the slider’s leading edge were detected. Increasing the x-offset of the suspension point made it possible to complete loading with 10 mm/s. At the same time, increasing the x-offset led to the slider-disk contact at the slider’s trailing edge in the beginning of loading with a velocity exceeding 25 mm/s.