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:
Nov. 04, 2003
Filed:
Jul. 27, 2000
Clyde Everett Goodner, III, Midwest City, OK (US);
Roy Lynn Wood, Oklahoma City, OK (US);
Lealon Ray McKenzie, Edmond, OK (US);
Seagate Technology LLC, Scotts Valley, CA (US);
Abstract
Method and apparatus for identifying a resonance by changing a spindle speed, which has the effect of changing a corresponding sampling rate and Nyquist frequency. The invention discriminates (1) between plausible frequencies of true resonance and/or (2) aliased resonance from non-aliased resonances. This is accomplished by monitoring whether and/or how a resonance shifts during this speed change. Methods of the present invention monitor resonances by deriving a resonance indicator such as an apparent frequency (below the Nyquist frequency), a gain or error magnitude (compared to a derived threshold at a calculated frequency of interest), or similar criteria tested by values conventionally illustrated on a Bode plot. The present invention further includes steps or structural features for configuring a controller to attenuate or similarly limit an unwanted frequency component of an actuator control signal. In this way, resonances in the actuator can be reduced, and servo speed and accuracy thereby enhanced.