Patent ID: 8902540
Filing Date: 2014-12-02
Classification: G11B

Abstract:
1. A disk storage apparatus comprising: a disk comprising a plurality of servo areas in which servo data for detecting a radial position is recorded in a divisional manner in the plurality of servo areas; a read module configured to read the servo data from the plurality of servo areas using a head; and a servo system comprising a state observer, wherein the servo system is configured to: perform a seek operation based on initial values including a temporary position, while allowing the state observer to operate based on the initial values, until a current position of the head is determined, if the seek operation up to a target position is performed while the current position of the head is undetermined; determine the current position based on the servo data read from the plurality of servo areas by the read module and a result of estimation by the state observer; and perform the seek operation up to the target position based on the determined current position, wherein the servo data is divided into upper position data and lower position data, the lower position data is recorded in each of the plurality of servo areas, and the upper position data is recorded in the plurality of servo areas in a divisional manner.