FEEDBACK CONTROL OF A THERMOMECHANICAL INPLANE MICROACTUATOR USING PIEZORESISTIVE DISPLACEMENT SENSING

Feedback control has proven useful in improving reliability and performance for a variety of systems. However there has been limited success implementing feedback control on surface micromachined MEMS devices. The inherent difficulties in sensing microscale phenomena complicate the development of an economical transducer that can accurately monitor the states of a surface micromachined system. We have demonstrated a simple and effective sensing strategy that uses the piezoresistive property of the polysilicon thin film of which surface micromachined MEMS devices are fabricated. The states of the device are monitored by measuring the change in resistance of flexible members which deflect as the device moves. Measurement of the output displacement of an in-plane thermal actuator is presented as a candidate application. While there still is a noise issue to be dealt with, this approach provides adequate signal strength to implement feedback control using off-chip analog circuitry. Implementation of proportional/integral control on the system is successfully demonstrated.Copyright © 2004 by ASME

[1]  Roberto Horowitz,et al.  High-bandwidth high-accuracy rotary microactuators for magnetic hard disk drive tracking servos , 1998 .

[2]  Mu Chiao,et al.  Electrothermal responses of lineshape microstructures , 1996 .

[3]  Derek G. Chetwynd,et al.  A SIMPLE TWO-AXIS ULTRAPRECISION ACTUATOR , 1994 .

[4]  Seung-Hi Lee,et al.  Design of a dual-stage actuator control system with discrete-time sliding mode for hard disk drives , 2000, Proceedings of the 39th IEEE Conference on Decision and Control (Cat. No.00CH37187).

[5]  R. Horowitz,et al.  Precision positioning using a microfabricated electrostatic actuator , 1999 .

[6]  Sergey Edward Lyshevski,et al.  Nonlinear microelectromechanical systems (MEMS) analysis and design via the Lyapunov stability theory , 2001, Proceedings of the 40th IEEE Conference on Decision and Control (Cat. No.01CH37228).

[7]  Christian D. Lott.  Electrothermomechanical Modeling of a Surface-micromachined Linear Displacement Microactuator , 2005 .

[8]  T. Hubbard,et al.  Time and frequency response of two-arm micromachined thermal actuators , 2003 .

[9]  R. Schellin,et al.  A silicon subminiature microphone based on piezoresistive polysilicon strain gauges , 1992 .

[10]  Nadim Maluf,et al.  An Introduction to Microelectromechanical Systems Engineering , 2000 .

[11]  Roberto Horowitz,et al.  Microfabricated electrostatic actuators for hard disk drives , 1998 .

[12]  Roberto Horowitz,et al.  Dual-stage track-following servo design for hard disk drives , 1999, Proceedings of the 1999 American Control Conference (Cat. No. 99CH36251).

[13]  L. Howell,et al.  On-chip actuation of an in-plane compliant bistable micromechanism , 2002 .

[14]  Timothy W. McLain,et al.  Modeling the thermal behavior of a surface-micromachined linear-displacement thermomechanical microactuator , 2002 .

[15]  Ray Bert,et al.  Book Review: Introduction to Transportation Systems by Joseph Sussman. Boston: Artech House, 2000 , 2002 .

[16]  Roberto Horowitz,et al.  Track-following controller design of MEMS based dual-stage servos in magnetic hard disk drives , 2000, Proceedings 2000 ICRA. Millennium Conference. IEEE International Conference on Robotics and Automation. Symposia Proceedings (Cat. No.00CH37065).

[17]  S. Majima,et al.  A control system to compensate the hysteresis by Preisach model on SMA actuator , 1998, MHA'98. Proceedings of the 1998 International Symposium on Micromechatronics and Human Science. - Creation of New Industry - (Cat. No.98TH8388).