Improvement of settling response of disk drive head positioning servo using mode switching control with initial value compensation

Author

Yamaguchi, Takashi ; Soyama, Yoshio ; Hosokawa, Haruhiko ; Tsuneta, K. ; Hirai, Hiromu

Author_Institution

Data Storage & Retrieval System Div., Hitachi Ltd., Odawara, Japan

Volume

32

Issue

3

fYear

1996

fDate

5/1/1996 12:00:00 AM

Firstpage

1767

Lastpage

1772

Abstract

A Mode Switching Control (MSG) design method for disk drive head positioning servo is proposed. The MSC includes several controllers and switches from one to the other to achieve both precise positioning and short seek time requirements. The issue is “settling”, the transient state after switching. This paper proposes the initial value compensation (IVC) method to improve transient characteristics after switching. Under the IVC method, certain values are placed in the state variables of the controller or an additional input is added at switching. From experimental data, we have proved that IVC reduces overshoot and slow transient response after switching. Also this IVC method does not affect any closed loop characteristics such as stability

Keywords

compensation; hard discs; initial value problems; magnetic heads; nonlinear control systems; position control; servomechanisms; transient analysis; transient response; closed loop characteristics; controller state variables; disk drive head positioning servo; initial value compensation; mode switching control design; nonlinear control; overshoot; precise positioning; settling response; short seek time requirements; slow transient response; stability; transient state; Control systems; Design methodology; Disk drives; Disk recording; Magnetic heads; Nonlinear control systems; Saturation magnetization; Servomechanisms; Switches; Target tracking;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/20.492863

Filename

492863