METHOD AND DEVICE FOR SELF-MONITORING/RECOVERING SPECIFIC FREQUENCY OF POSITION ERROR ON DATA STORAGE BY BLOCKING DISTURBANCE FREQUENCY

摘要

PURPOSE: A method and a device for self-monitoring/recovering a specific frequency of a position error on a data storage are provided to detect and/or correct an error on the data storage caused by the NRRO(Non-Repeatable RunOut) or other mechanical excitation, and to block disturbance frequency. CONSTITUTION: A controller(70) partially includes a servo control loop(72) equipped with a track-following controller(74) driving an actuator(60). A PES(Position Error Signal) from the actuator is fed back to the track-following controller and the track-following controller generates an actuator control signal(78) by responding to the PES. A rejection filter(80) selectively filters the actuator control signal output to the actuator depending on a pair of switches(82,84). The rejection filter and a peak filter(88) are a narrowband filter for rejecting or separating a disturbance frequency related to the NRRO and the mechanical excitation.