A modal analysis method for slider-air bearings in hard disk drives

A system identification method using modal analysis is proposed to analyze the dynamic characteristics of slider-air bearings in hard disk drives. A procedure for estimating the modal parameters, as well as the stiffness and damping matrices, is presented. The "Nutcracker" slider used as an example is analyzed, and the results are verified. The differences of the stiffness matrices calculated through different methods are found and explained. The results of the example show the assumptions of the method are satisfied in a wide amplitude range. Therefore the technique provides a powerful tool for head-medium interface analysis and experiment.