The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 27, 1999
Filed:
Jul. 29, 1997
Thomas L Andrews, Ward, CO (US);
Robert A Alt, Longmont, CO (US);
Steven J Mertens, Longmont, CO (US);
Gary E Counts, Arvada, CO (US);
Ronald J Loomis, Littleton, CO (US);
Mobile Storage Technology, Inc., Boulder, CO (US);
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.