Vibration and Stability of a Read/Write Head Floppy Disk System Subjected to External Axial and Pitching Oscillations

Abstract

This paper is a study of the vibration and stability of a read/ write head disk system subjected to external disturbances. The analytical solution is obtained by applying the model expansion method to the disk governing the equations. In the analysis, the read/write head is modeled as a mass-spring system and the stiffness of the air film in the disk cover is approximated by the stiffness of uniform springs resting under the disk. The axial and the pitching sinusoidal excitations are considered as external disturbances. It is shown that the frequency range where the system has a high response amplitude is affected significantly by the location of the R/W head on the disk. Furthermore it is noted that there is on optimum value of the air film stiffness in disk cover to stabilize the whole disk system over a wide range of operating speeds.