CMU MEMS Laboratory Publication Abstract

 

in IEEE/ASME Journal of Microelectromechanical Systems, Volume 13, Issue 2, pp. 759-769, October 2004.
Position Control of Parallel-Plate Microactuators for Probe-Based Data Storage
M. S. Lu and G. Fedder
ABSTRACT:
In this paper, we present the use of closed-loop voltage control to extend the travel range of a parallel-plate electrostatic microactuator beyond the pull-in limit. Controller design considers nonlinearities from both the parallel-plate actuator and the capacitive position sensor to ensure robust stability within the feedback loop. Desired transient response is achieved by a pre-filter added in front of the feedback loop to shape the input command. The microactuator is characterized by static and dynamic measurements, with a spring constant of 0.17 N/m, mechanical resonant frequency of 12.4 kHz, and effective damping ratio from 0.55 to 0.35 for gaps between 2.3 to 2.65 µm. The minimum input-referred noise capacitance change is 0.5 aF/ÖHz measured at a gap of 5.7 µm, corresponding to a minimum input-referred noise displacement of 0.33 nm/ÖHz. Measured closed-loop step response illustrates a maximum travel distance up to 60% of the initial gap, surpassing the static pull-in limit of one-third of the gap.
© 2004 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE.
Full paper (PDF) (opens in new window).


This page was generated in 0.0121 seconds at 02:05:07 pm UTC on 26 Apr 2024.

overview | projects | people | publications | intranet | resources         © 1998-2009  Carnegie Mellon