Numerical simulation and animation of head-disk-assembly dynamics

A general-purpose numerical simulation program for the dynamic response of the head-disk assembly (HDA) is presented. The HDA parts studied are the suspension assembly, the slider, the air-bearing, and the disk. The surface-roughness effects and slider-disk contact are also considered. By integrating every component of the HDA, the program can accurately predict the response of the HDA to various disturbances. Some of the results presented are a slider flying over a surface defect on the disk, track-accessing, and crash-stop. Furthermore, since the suspension assembly is analyzed using the finite-element method, any suspension assembly geometry can be analyzed. The method is based on the modal decomposition of the equations of motion. This method provides an efficient solution of the equation of motion of the head-disk assembly without requiring the finite-element mass and stiffness matrices. An animation program that uses the GL library routines available for the IBM RS/6000 workstations was developed to provide enhanced visual display of the simulation solutions