Adaptive calibration of read/write elements in a disc drive
US5774299A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 13, 1996 |
| Grant date | Jun 30, 1998 |
| Priority date | — |
| Expiry date | Aug 13, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/59644
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The track follow gain control of an actuator controller is calibrated by injecting a sinusoidal signal into the position error signal during a servo burst interrupt. The injected signal is bandpass filtered to optimize the coherence of the measurement. A sine error signal is derived based on the filtered (sine actual) signal and a sine desired signal. The sine error signal is applied to the track follow gain control to adjust the amplitude of the control signal to the actuator based on the sine error signal. The sine error is derived by averaging the peaks of the filtered injected signal and subtracting the averaged signal from the desired signal which represents the expected error of the sinusoidal signal under ideal conditions. The recording surfaces may be segmented into a plurality of radial zones in which case a central track is identified in one zone on a selected disc surface. The sine error signal is derived for that zone, after which the process is repeated for the corresponding zone of each other recording surface. The sine error signals derived from the several disc surfaces are averaged to adjust the track follow gain control for the common zone of all disc surfaces.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.