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. 25, 2014
Filed:
Jun. 16, 2011
Min Chen, San Leandro, CA (US);
Alain Chahwan, Mission Viejo, CA (US);
Shang-chen Wu, Milpitas, CA (US);
Qixing Zheng, Albany, CA (US);
Alexander Babinski, Laguna Niguel, CA (US);
Duc T. Phan, Saratoga, CA (US);
Min Chen, San Leandro, CA (US);
Alain Chahwan, Mission Viejo, CA (US);
Shang-Chen Wu, Milpitas, CA (US);
Qixing Zheng, Albany, CA (US);
Alexander Babinski, Laguna Niguel, CA (US);
Duc T. Phan, Saratoga, CA (US);
Western Digital Technologies, Inc., Irvine, CA (US);
Abstract
A disk drive comprises a track follow control system having a plurality of selectable frequency modes, the track follow control system configured to receive a position error signal and to output a control signal based on the position error signal, wherein the control signal is used by a head assembly to position a head over a disk. The disk drive also comprises a state estimator configured to receive the control signal and a position signal indicating a position of the head, to estimate a disturbance based on the control signal and the position signal, and to output an estimated disturbance signal based on the estimated disturbance. The disk drive further comprises a disturbance evaluator configured to receive the estimated disturbance signal, and to select one of the frequency modes of the track follow control system based on the estimated disturbance signal.