I-002
Design Analysis of a Grating Interferometer Sensor for HDD Servo-Track Writing
Authors: Harry Garner, Kok-Meng Lee, Lin Guo
Affiliation: Georgia Institute of Technology, Georgia Institute of Technology, Maxtor
Corporation
Abstract
A grating interferometer system for the measurement of a hard disk drive actuator
arm during the servo-track writing process has been designed and analyzed. Attractive
features of this grating interferometer based system over current measurement systems
such as the mechanical and optical push-pin techniques are that it does not require
contact with the actuator arm and only needs a single servo loop to control the actuator
arm position. In this paper, the theory necessary for the design of a grating interferometer
based system to perform a non-contact direct measurement of a hard disk drive actuator
arm for use in servo-track writing will be presented. First, the theoretical background
related to the linear type grating interferometer is presented, and this theory is
extended to the measurement of the angular displacement of a hard disk drive actuator
arm using a linear grating. Finally, experimental results with a prototype grating
interferometer measurement system are presented and discussed.
Harry Garner
Department of Mechanical Engineering
Georgia Institute of Technology
(404) 894-8169
hgarner@sun1.hu.edu