Bias Compensation for Fast Servo Track Writer Seek Control

Author

Kang, Hyun Jae ; Kim, Kyung-soo ; Seung-Hi Lee ; Chung, Chung Choo

Author_Institution

Dept. of Electr. Eng., Hanyang Univ., Seoul, South Korea

Volume

47

Issue

7

fYear

2011

fDate

7/1/2011 12:00:00 AM

Firstpage

1937

Lastpage

1943

Abstract

This paper presents fast servo track writer seek control for unknown bias compensation and minimum resonance excitation. An add-on type discrete-time disturbance observer is also employed to obtain uniform settling performance in the presence of disturbance. To prevent a chattering effect due to the unstable zero dynamics of servo track writer, we propose a new disturbance observer dynamics. A two-degree-of-freedom control is used with the reference profile design based on the frequency shaped final-state control and compensation of phase mismatching. We analyze the experimental results of the servo track writer for fast seeking and settling. The proposed control scheme is validated by experimental results showing improvements in seeking and settling performance.

Keywords

compensation; control nonlinearities; discrete time systems; hard discs; observers; servomechanisms; add-on type discrete time disturbance observer; bias compensation; chattering effect; disturbance observer dynamics; fast servo track writer seek control; frequency shaped final-state control; phase mismatch; reference profile design; resonance excitation; two-degree of freedom control; unstable zero dynamics; Ball bearings; Frequency control; Mathematical model; Observers; Resonant frequency; Servomotors; Trajectory; Bias compensation; disturbance observer; servo track writer;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/TMAG.2011.2129496

Filename

5928986