DynaMic Aeroacoustic Microphone and Dynamic Pressure Sensor
The research surrounding the new DynaMic aeroacoustic microphones and dynamic pressure sensors is now published and available for download here. The paper titled, “A Miniaturized, Flush-Mount, IEPE MEMS Piezoelectric Pressure-Field Microphone for Aeroacoustic Applications” which was presented at the 30th AIAA/CEAS Aeroacoustics Conference, covers the processes it took to develop this fully calibrated pressure transducer.
Innovative MEMS Microphone for Dynamic Pressure Sensing
From the paper’s abstract, “This paper describes the development and experimental characterization of a miniaturized, flush-mount aeroacoustic pressure-field microphone designed for through-wall installation applications such as aeroacoustic microphone phased arrays and dynamic pressure sensing. The aluminum nitride piezoelectric microelectromechanical systems (MEMS) sensor is fabricated using a novel, low-cost approach to creating backside electrical contacts, creating a hydraulically smooth surface without the use of through-silicon vias. An integrated electronic piezoelectric (IEPE) preamplifier contained within a 3.18 𝑚𝑚 diameter, 17 𝑚𝑚 long sensor package enables operation of the sensor using commercially available IEPE-enabled data acquisition systems.
Characterization includes measurement of sensing surface smoothness, sensitivity, linearity, total harmonic distortion (THD), minimum detectable pressure (MDP), and frequency response from 5 𝐻𝑧 to the upper frequency limit of the device using a reciprocal calibration method that is uniquely suited for piezoelectric transduction. Characterization of the device demonstrates similar performance to previously developed piezoelectric aeroacoustic microphones in a much smaller form factor, with a sensitivity of 109 𝜇𝑉/𝑃𝑎, ±3 𝑑𝐵 bandwidth of 14 𝐻𝑧 to 116 𝑘𝐻𝑧, minimum detectable pressure (MDP) of 43.6 𝑑𝐵𝑆𝑃𝐿, and experimentally verified dynamic range in excess of 128 𝑑𝐵.”
A Fully-Calibrated Pressure Transducer with Minimal Flow Disturbance
DynaMic is a miniaturized, flush-mountable aeroacoustic pressure-field microphone designed for through-wall installation applications such as aeroacoustic microphone phased arrays and fluctuating pressure sensing. DynaMic features an ultra-smooth (~10 µm), ultra-flush-mountable sensor with a known, small sensing area (0.75 mm diameter diaphragm). IC2’s innovative approach enables higher density acoustic arrays, with significantly reduced cost per channel, resulting in higher channel-count arrays comprised of high-bandwidth, high dynamic range, flush-mounted aeroacoustic microphones. Multiple small vents etched through the diaphragm are used to equilibrate the static pressure between the cavity and the test environment, enabling use in vacuum and/or pressurized facilities.
IC2’s patented reciprocal calibration methodology is available for both magnitude and phase over the complete measurement bandwidth. Back-side contact piezoelectric MEMS microphones, combined with advanced packaging techniques, enable ultra-smooth sensor installation – eliminating flow disturbances generated by the sensor itself.
DynaMic’s known magnitude and phase characteristics, and its well-defined sensing area, bound the uncertainty of your correlation and spectral measurements providing measurement scientists with a clear choice in selecting an aeroacoustic and dynamic pressure sensing solution.
