Patent ID: 6958882

Claim:
A rotational recording apparatus comprising: a head for reading data from a rotatable recording medium; head driving means for driving said head; head position detection means for outputting current data for a position of said head on said recording medium; a controller for receiving a deviation between said current position data and a target position, and for generating a feedback control signal to be transmitted to said head driving means; a sensor for detecting a disturbance that acts on said rotational recording apparatus; a bandpass filter for passing an output signal of said sensor in a predetermined frequency band, wherein a pass band for said bandpass filter has a range between 200 Hz and 500 Hz; an adaptive filter for receiving said output signal of said bandpass filter and for generating a feed forward control signal to be transmitted to said head driving means; a phase shift filter for shifting a phase of said output signal of said bandpass filter; and adaptive algorithm means for calculating coefficients for said adaptive filter using said deviation and the signal output by said phase shift filter.