Self-servowriting system with dynamic error propagation reductio

Details Self-servowriting system with dynamic error propagation reductio Self-servowriting system with dynamic error propagation reductio

1996-07-09

1998-08-11

Sniezek, Andrew L.

Dynamic magnetic information storage or retrieval

Automatic control of a recorder mechanism

Controlling the head

360 7708, G11B 5596

Patent

active

057935548

ABSTRACT:
A self-servowriting system and method for implementation in a storage device such as a disk drive are described. Two problems associated with self-propagation are greater mechanical disturbances and the growth of errors during many thousands of servowriting steps. Error growth is attributable to the special properties of servo loops as applied to a repetitive self-propagation process. Greater resistance to mechanical disturbances and reduction in error growth are achieved, in part, by adjusting a step amplification factor, S, at the initiation of servowriting to within desired parameters. However, S is known to vary with movement of the head in a direction transverse to the direction of the tracks. This problem is addressed by the present invention, wherein S is determined at a plurality of transverse transducer positions. S is dependent upon the closed loop response of the servo system C and upon a set of step-to-step correction factors f. S is therefore determined by monitoring an indicium of S such as C, and is adjusted by adjusting either C or f to provide a value of S which falls within an acceptable range of values. Determination of S is scheduled to occur at predefined intervals. The intervals may be fixed or adjusted adaptively based upon the measured variation of S with transducer position.

REFERENCES:
patent: 3881184 (1975-04-01), Koepcke et al.
patent: 4414589 (1983-11-01), Oliver et al.
patent: 4563058 (1986-01-01), Yardy
patent: 4912576 (1990-03-01), Janz
patent: 5003412 (1991-03-01), Bizjak et al.
patent: 5241433 (1993-08-01), Anderson et al.
patent: 5444583 (1995-08-01), Ehrlich et al.
patent: 5448429 (1995-09-01), Cribbs et al.
patent: 5475291 (1995-12-01), Yoshida et al.
patent: 5485322 (1996-01-01), Chainer et al.
patent: 5541784 (1996-07-01), Cribbs et al.
patent: 5570247 (1996-10-01), Brown et al.
patent: 5612833 (1997-03-01), Yarmchuk et al.
patent: 5659436 (1997-08-01), Yarmchuk et al.
Anonymous, Compensation Technique for External Vibration for Direct Access Storage Devices (DASD), Research Disclosure, May 1992, No. 33761, pp.375.
Elliot, P.J., Data Head Self Servowrite, IBM Technical Disclosure Bulletin, vol. 32, No. 9A, Feb. 1990, pp. 20-22.
Anonymous, Regenerative Clock Technique for Servo Track Writers, IBM Technical Disclosure Bulletin, vol. 33, No. 5, pp. 310-311., Oct. 1990.

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