US 20060291101A1
(i9) United States
(12) Patent Application Publication oo) Pub. No.: US 2006/0291101 Al
Takaishi (43) Pub. Date: Dec. 28,2006
(54) HEAD POSITION CONTROL METHOD,
HEAD POSITION CONTROL DEVICE, AND
DISK DEVICE
(75) Inventor: Kazuhiko Takaishi, Kawasaki (JP)
Correspondence Address:
GREER, BURNS & CRAIN
300 S WACKER DR
25TH FLOOR
CHICAGO, IL 60606 (US)
(73) Assignee: FUJITSU LIMITED
(21) Appl. No.: 11/362,601
(22) Filed: Feb. 23, 2006
(30) Foreign Application Priority Data
Jun. 27, 2005 (JP) 2005-187029
Publication Classification
(51) Int. CI.
G11B 5/48 (2006.01)
(52) U.S. CI 360/244
(57) ABSTRACT
A position control device corrects the displacement of the head by disturbance applied to the disk device by the control system. An adaptive control to an unknown disturbance frequency is performed. The frequency estimation block for estimating the external vibration frequency from a signal that is based on the position error according to the adaptive rule, and a correction table for sequentially correcting the constants of the compensator using this external vibration frequency, are provided. Since the constants of the compensator are sequentially corrected according to the estimated angular frequency, highly accurate follow up control to an external vibration frequency in a wide range becomes possible.
