US 6,982,848 B2
Disk apparatus and head positioning method
Toshio Inaji, Osaka (Japan); Keizo Miyata, Kyoto (Japan); Hiroshi Kohso, Osaka (Japan); and Makoto Umeda, Osaka (Japan)
Assigned to Matsushita Electric Industrial Co., Ltd., Osaka (Japan)
Filed on May 25, 2004, as Appl. No. 10/852,135.
Claims priority of application No. 2003-154380 (JP), filed on May 30, 2003; and application No. 2003-171524 (JP), filed on Jun. 17, 2003.
Prior Publication US 2004/0240101 A1, Dec. 02, 2004
Int. Cl. G11B 5/596 (2006.01); G11B 21/02 (2006.01)
U.S. Cl. 360—77.02 26 Claims
OG exemplary drawing
 
1. A disk apparatus, comprising:
an actuator including a voice coil motor, an arm provided to the voice coil motor, and a head attached to the arm for recording and/or reproducing information;
driving means for driving the actuator, the driving means receiving a driving signal used for driving the actuator and a pseudo disturbance signal that simulates disturbance applied to the actuator;
a voltage detection means for detecting a voltage induced in the voice coil motor by the driving of the actuator to output a first voltage signal which corresponds to the detected voltage;
voltage signal adjustment means for outputting the pseudo disturbance signal, receiving the driving signal, a disturbance estimation signal that estimates disturbance, and the first voltage signal, and adjusting the first voltage signal such that a deviation of a coil resistance of the voice coil motor from a nominal value is corrected except for the times of recording and reproduction of the information, thereby generating a second voltage signal; and
disturbance estimation means for estimating the magnitude of the disturbance applied to the actuator from the driving signal and the second voltage signal to generate the disturbance estimation signal.