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:
Jan. 14, 2014
Filed:
Feb. 29, 2012
Xu Chen, Albany, CA (US);
Wei Xi, Mission Viejo, CA (US);
Young-hoon Kim, Cupertino, CA (US);
Kuang-yang Tu, Irvine, CA (US);
Xu Chen, Albany, CA (US);
Wei Xi, Mission Viejo, CA (US);
Young-Hoon Kim, Cupertino, CA (US);
Kuang-Yang Tu, Irvine, CA (US);
Western Digital Technologies, Inc., Irvine, CA (US);
Abstract
A disk drive comprises a disk, an actuator arm and a servo controller using a position error signal to generate a controller output signal to control the actuator arm. A plant mechanically models at least a portion of the disk drive, receives a control command to which an unknown disturbance is added and generates a plant output. A disturbance observer (DOB) uses the control command and the plant output to generate a delayed and estimated version of the disturbance. The DOB comprises a Q filter having a selected center frequency. A perfect phase cancellation filter (PPCF) is configured to receive the delayed and estimated version of the disturbance, to reject selected disturbances and to align the desired attenuation frequency with the selected center frequency. The output of the PPCF is subtracted from the controller output signal to generate the control command.