This paper describes a hybrid approach for modeling nonlinear vibrations and determining essential (normal form) coefficients that govern a reduced-order model of a structure. Incorporating both computational and analytical tools, this blended method is demonstrated by considering a micro-electro-mechanical vibrating gyroscopic rate sensor that is actuated by segmented DC electrodes. Two characterization methods are expatiated, where one is more favorable in computational tools and the other can be used in experiments. Using the reduced model, it is shown that tuning the nonuniform DC bias results in favorable changes in Duffing and mode-coupling nonlinearities which can improve the gyroscope angular rate sensitivity by two orders of magnitude.
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Maximizing the rate sensitivity of resonating gyroscopes using nonlinear shape optimization
Abstract In this work we demonstrate how one can improve the angular rate sensitivity of ring/disk resonating gyroscopes by tailoring their nonlinear behavior by systematic shaping of the gyroscope body and electrodes, and by the tuning of bias voltages on segmented electrodes. Of specific interest are the drive and sense mode Duffing nonlinearities, which limit their dynamic ranges, and the intermodal dispersive coupling between these modes that provides parametric amplification of the sense mode output signal. These two effects have the same physical origins and are in competition in terms of system performance, which naturally calls for optimization considerations. The present analysis is based on a systematic modeling of the nonlinear response of these devices by which we explore ways in which one can optimize the angular rate sensitivity by manipulating the mechanical and electrostatic contributions to the nonlinearities. In particular, non-uniform modifications of the gyroscope body thickness are employed to affect the mechanical contributions to these parameters, while the electrostatic components are manipulated via shaping of the resonator-electrode gap and by applying non-uniform bias voltages among segmented electrodes around the gyroscope body. These models predict that such relatively simple alterations can achieve improvements in gain by about an order of magnitude when compared to devices with uniform layouts.
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- Award ID(s):
- 1662619
- NSF-PAR ID:
- 10385842
- Date Published:
- Journal Name:
- Journal of Micromechanics and Microengineering
- Volume:
- 32
- Issue:
- 6
- ISSN:
- 0960-1317
- Page Range / eLocation ID:
- 064003
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Ring laser gyroscopes (RLGs) based on non-Hermitian exceptional points (EPs) have garnered much recent interest due to their exceptional sensitivity. Such gyroscopes typically consist of two-ring laser resonators, one with loss and one with an equal amount of optical gain. The coupling strength between these ring resonators is a key parameter determining the sensitivity of EP-based RLGs. Here we explore how the exceptional sensitivity demonstrated in this coupled dimer may be further enhanced by adding more dimers in an array. Specifically, we propose two types of ring laser gyroscope lattice arrays, each composed of
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1088/1361-6439/ac6c74
