Dynamic magnetic information storage or retrieval – Automatic control of a recorder mechanism – Controlling the head
Patent
1996-07-22
1999-07-13
Hindi, Nabil
Dynamic magnetic information storage or retrieval
Automatic control of a recorder mechanism
Controlling the head
360 7708, 360 53, 360 65, G11B 5596
Patent
active
059234911
ABSTRACT:
The present invention determines whether a filter is used for reading and writing on a disk to correct repeatable runout. The invention estimates the magnitude of repeatable runout for each disk by measuring the maximum absolute value of a state variable of a filter when the disk is turned on or when the disk returns from a sleep mode, and compares the measured value to a predetermined criterion such as the track width. If the magnitude of the repeatable runout is less than or equal to the predetermined criterion, the filter is not used. If the magnitude of the repeatable runout exceeds the predetermined criterion, the invention reads and writes data using the filter.
REFERENCES:
patent: 4096534 (1978-06-01), Brownback et al.
patent: 4616276 (1986-10-01), Workman
patent: 5065263 (1991-11-01), Yoshida et al.
patent: 5072318 (1991-12-01), Yu
patent: 5210660 (1993-05-01), Hetzler
patent: 5257252 (1993-10-01), Barnes et al.
patent: 5444583 (1995-08-01), Ehrlich et al.
patent: 5535072 (1996-07-01), Witt et al.
patent: 5539714 (1996-07-01), Andrews, Jr. et al.
patent: 5550685 (1996-08-01), Drouin
patent: 5553086 (1996-09-01), Sompel et al.
Anonymous, "Iterative Feedforward Error Sum Method for ACRMS Reduction in Direct Access Storage Device Files", Research Disclosure, Jul. 1992 vol. 339, No. 33903.
Jefferson et al, "Head-Disk Spacing Controller for Magnetic Recording", IBM Technical Disclosure Bulletin, vol. 31 No. 11, Apr. 1989, pp. 240-241.
Kisaka Masashi
Kitazaki Nobuyuki
Nakamura Takashi
Yokoe Yuji
Yoneda Isao
Hindi Nabil
International Business Machines - Corporation
LandOfFree
Disk drive servo control system with selectable filtering for re does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Disk drive servo control system with selectable filtering for re, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Disk drive servo control system with selectable filtering for re will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2281896