Abstract: A method and apparatus for identifying and filtering a resonance frequency of a support structure supporting a read/write head in proximity with a data storage medium involves obtaining a particular sample of a position error signal (PES) frequency transform, preferably using Goertzel's algorithm. The velocity of the data storage medium is varied, and the magnitude of a particular PES frequency transform sample is computed at each of the velocities. A resonance frequency of the support structure is calculated using the velocity associated with the particular sample having a maximum magnitude. The effects of one or more resonance frequencies associated with a read/write head suspension may be canceled in a position error signal using one or more programmable filters provided in each servo loop. A processor programs the filters using the calculated resonance frequencies and adjusts to compensate for the additional lag introduced into the respective servo loops by the selected programmable filters.
Type:
Grant
Filed:
December 2, 1998
Date of Patent:
July 9, 2002
Assignee:
International Business Machines Corporation
Inventors:
Hal Hjalmar Ottesen, Gordon James Smith