Description
The objective of this project was to characterize and model two designs of a capacitive micromachined ultrasonic transducer (cMUT) for medical ultrasound purposes.
As a relatively new MEMS technology, cMUTs have become a competitive alternative to the regularly used piezoelectric transducers in the medical diagnostic field. Due to several advantages that they hold over piezoelectric transducer materials, the research and development of cMUTs have increased greatly over the past couple of decades, and will continue to do so into the future.
The specific goals of this thesis were to provide a hybrid finite element/lumped element modeling scheme for cMUT elements and arrays, and to compare the predictions to laser Doppler velocimetry measurements.
Research began with developing an understanding of lumped element acoustic modeling, and from this, a lumped element acoustic model was created for the cMUT designs. Cross-sectional models for the different geometries of the cMUTs were created using COMSOL 3.3 Multiphysics, in order to determine the values for several of the lumped model’s elements. After creating a computational model through the use of Matlab, frequency plots were generated for the transducers in both air and water environments.
A magnified view of the first cMUT elements, arranged in a 7 element array
References
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Arduino and MATLAB code for textile sensors for embedded pressure sensing of orthopedic casts
Chloe –
Outstanding work!