Methods for closed-loop compensation of ultra-high frequency disturbances in hard disk drives and hard disk drives utilizing same
US8630059B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 29, 2012 |
| Grant date | Jan 14, 2014 |
| Priority date | — |
| Expiry date | Jul 20, 2032 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/59694
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
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.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.