In this study, a combined threshold pressure sensor
and switch is introduced. The sensor detects when the pressure
drops below a threshold value and automatically triggers a
switch without the need for any computational overhead to
read the pressure or trigger the switch. This system exploits
the significant fluid interaction of a MEMS beam undergoing a
large oscillation from electrostatic levitation to detect changes
in ambient pressure. The levitation electrode configuration is
combined with a parallel-plate system by adding an extra voltage
to an electrode that is traditionally grounded, giving the system
the ability to simultaneously act as a switch by toggling to and
from the pulled-in position. It is experimentally demonstrated
that the pressure sensing/switching mechanism is feasible and
the threshold pressure to trigger the switch can be controlled by
adjusting the voltage applied to the switch electrode.
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A tunable Electrostatic MEMS Pressure Switch
We demonstrate a tunable air pressure switch. The switch detects when the ambient pressure drops below a threshold value and automatically triggers without the need for any computational overhead to read the pressure or trigger the switch. The switch exploits the significant fluid interaction of a MEMS beam undergoing a large oscillation from electrostatic levitation to detect changes in ambient pressure. If the oscillation amplitude near the resonant frequency is above a threshold level, dynamic pull-in is triggered and the switch is closed. The pressure at which the switch closes can be tuned by adjusting the voltage applied to the switch. The use of electrostatic levitation allows the device to be released from their pulled-in position and reused many times without mechanical failure. A theoretical model is derived and validated with experimental data. It is experimentally demonstrated that the pressure switching mechanism is feasible.
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- Award ID(s):
- 1608692
- PAR ID:
- 10127762
- Date Published:
- Journal Name:
- IEEE Transactions on Industrial Electronics
- ISSN:
- 0278-0046
- Page Range / eLocation ID:
- 1 to 1
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1109/TIE.2019.2956377
