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:
Mar. 04, 2014
Filed:
Dec. 22, 2011
Brian P. Rigney, Louisville, CO (US);
Edgar D. Sheh, San Jose, CA (US);
Siri S. Weerasooriya, Campbell, CA (US);
Brandon P. Smith, San Jose, CA (US);
Brian P. Rigney, Louisville, CO (US);
Edgar D. Sheh, San Jose, CA (US);
Siri S. Weerasooriya, Campbell, CA (US);
Brandon P. Smith, San Jose, CA (US);
Western Digital Technologies, Inc., Irvine, CA (US);
Abstract
A disk drive is disclosed comprising a disk, a head, and a voice coil motor (VCM) operable to actuate the head over the disk, wherein the VCM generates a back electromotive force (BEMF) voltage. At least one reference track is written on the disk, and the head is positioned near a first diameter of the disk. While moving the head from the first diameter toward a second diameter of the disk, the reference track is read and a first estimated state error is measured. While moving the head from the second diameter of the disk toward the first diameter of the disk, the reference track is read and a second estimated state error is measured. A gain and an offset of a velocity sensor are adjusted in response to the first and second estimated state errors.