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:
Jun. 23, 2009
Filed:
Aug. 21, 2007
Zhi Wang, Irvine, CA (US);
Jenghung Chen, Cupertino, CA (US);
Zhi Wang, Irvine, CA (US);
Jenghung Chen, Cupertino, CA (US);
Western Digital Technologies, Inc., Lake Forest, CA (US);
Abstract
Disclosed is a disk drive and method to characterize misaligned servo wedges. The disk drive includes an actuator arm, a head, a disk, and a servo controller. The head is connected to a distal end of the actuator arm in which the actuator arm is rotatable about a pivot to move the head radially over the disk. The servo controller is used to characterize misaligned servo wedges by implementing operations including: commanding the head to track follow on a track; measuring wedge-to-wedge time (WTWT) values corresponding to time intervals between identified servo wedges; calculating wedge-to-wedge time (WTWT) variations for the measured WTWT values; and characterizing the calculated WTWT variations, wherein, characterizing the calculated WTWT variations for the track includes utilizing a WTWT variation modeling function to model the WTWT variations.