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Title: A MEMS Threshold Acceleration Switch Powered by a Triboelectric Generator
In this paper a novel electrostatic MEMS combined shock sensor and normally-closed switch is presented. The switch uses combined attractive and repulsive forcing to toggle a cantilever beam to and from the pulled-in position. The attractive force is generated through a parallel plate electrode configuration and induces pull-in. The repulsive force is generated through electrostatic levitation from a third electrode and serves to pull the beam out of its pulled-in position. A triboelectric transducer converts impact energy to electrical energy to provide voltage for the third electrode, which temporarily opens the switch if enough impact energy is supplied. Triboelectricity addresses the high voltage requirement for electrostatic levitation. The multi-electrode sensor also addresses the low current output from the generator because it acts as an open circuit between the parallel plate and levitation electrodes. A theoretical model of the switch is derived to analyze stability and the dynamic response of the cantilever. Threshold voltages to pull-in and release the beam through repulsive forcing is calculated. Output voltage plots from a prototype generator under a single impact are applied to the sensor-switch model to demonstrate the working principle of the sensor-switch is feasible.  more » « less
Award ID(s):
1608692
PAR ID:
10104333
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Proceedings of the ASME 2018 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference
Page Range / eLocation ID:
V004T08A010
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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