Fabrication of MEMS Directional Acoustic Sensors for Underwater Operation
| Autor: | Gamani Karunasiri, Alberto Espinoza, German Da Re, Renato Rabelo, Fabio Alves |
|---|---|
| Přispěvatelé: | Naval Postgraduate School, Physics |
| Jazyk: | angličtina |
| Rok vydání: | 2020 |
| Předmět: |
Fabrication
Materials science Frequency band Acoustics 02 engineering and technology underwater lcsh:Chemical technology 01 natural sciences Biochemistry Article Analytical Chemistry law.invention law sensor lcsh:TP1-1185 Electrical and Electronic Engineering Underwater Sound pressure Instrumentation Microelectromechanical systems 010401 analytical chemistry Acoustic source localization 021001 nanoscience & nanotechnology Atomic and Molecular Physics and Optics 0104 chemical sciences Capacitor MEMS directional 0210 nano-technology Sensitivity (electronics) |
| Zdroj: | Sensors, Vol 20, Iss 5, p 1245 (2020) Sensors Volume 20 Issue 5 Sensors (Basel, Switzerland) |
| Popis: | In this work, microelectromechanical systems (MEMS)-based directional acoustic sensors operating in an underwater environment are explored. The studied sensors consist of a free-standing single wing or two wings pivoted to a substrate. The sensors operate in a narrow frequency band determined by the resonant frequency of the mechanical structure. The electronic readout of the mechanical response is obtained using interdigitated comb finger capacitors attached to the wings. The characteristics of MEMS sensors immersed in silicone oil are simulated using finite element modeling. The performance of the sensors is evaluated both in air and underwater. For underwater testing and operation, the sensors are packaged in a housing containing silicone oil, which was specially developed to present near unity acoustic transmission. The measurements show that the resonant frequency of the sensors obtained in air shifts to a lower frequency when immersed in silicone oil, which is primarily due to the mass loading of the liquid. The peak sensitivity of the MEMS sensors is approximately 6 mV/Pa or &ndash 165 dB re 1 V/mPa, and the directional response shows a dipole pattern. The signal-to-noise ratio was found to be about 200 or 23 dB at 1 Pa incident sound pressure. The results show the potential of MEMS sensors to be used in underwater applications for sound source localization. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|