Estimation of Disk Slip Position Error for Mobile Hard Disk Drives

Mechanical vibration on mobile hard disk is inevitable in the practical usage, and violent vibration may cause disk slip with significant position error, which will degrade the servo control performance, prolong time to ready (TTR) of servo and lower reading and writing speed of the magnetic head. The servo tracking accuracy of hard disk drive actuator with respect to various mechanical disturbance levels was considered. So this paper proposes an analytic method based on the motion law of magnetic head against the media in order to effectively estimate the resulting position error prior to the seeking operation and reduce servo burden with control performance improved. Keywords—hard disk; slip; position error