Method and apparatus for electronically shifting mechanical resonance of an actuator system of a disc drive

Abstract

A disc drive actuator system includes an equalizer filter coupled between the controller and actuator plant of a disc drive actuator system. The filter applies a gain of less than unity gain to the actuator drive signals from the controller at the resonance frequency of the plant, and applies a gain greater than unity to the actuator drive signals at a selected frequency different from the plant resonance frequency to derive a system resonance frequency shifted from the plant resonance frequency. In one form the equalizer filter functions as a notch filter to attenuate signals at the plant resonance frequency, and functions as a peak filter to boost the gain of higher frequency signals over a band wide enough to ensure zero phase loss below the plant resonance frequency.

Dependencies are inferred from the claim text.