Patent · US Expired

Multi-harmonic compensator for track following in disk drives

US5930067A · kind A · utility

16Cited by
3References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 29, 1997
Grant dateJul 27, 1999
Priority date
Expiry dateJul 29, 2017

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B5/596
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

An adaptive servo system for a disk drive compensates for a track being off center or distorted by analyzing the spectral content of the radial variation of the centerline of a track relative to a rotation axis, generating multiple component signals having frequencies that are harmonics of the rotation frequency, and combining the component signals in a positioning signal for an actuator. Analyzing the spectral content of the radial variation can be accomplished by a discrete Fourier transform of a position error signal while generating a correction signal that cancels all or part of previously determined components of the position error signal. The system converges to generating a periodic signal that compensates for multiple harmonics in the radial variation in the position of the track.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.