Design of Centrally Supported Biomimetic MEMS Microphone for Acoustic Source Localization

Biologically inspired unique perforated diaphragm architecture for acoustic source localization has been designed. The merely 500 μm separated structure of ears of fly Ormia ochracea which increases the interaural time and intensity differences of arriving sound has great ability to enhance the acoustic source localization. This remarkable capacity of fly to amplify direction cues for incoming sound along with squeeze film damping effects are the key inspirations for designing the diaphragm. In this design, we maintain a unique ratio between the number of holes and the diaphragm size and enhanced the acoustic directional sensitivity cues. A mechanical structure based on the ears of fly Ormia ochracea is modeled and the response is observed on different frequencies by considering the critical damping value and also on zero damping value. In one step further a perforated diaphragm is designed utilizing ANSYS software and is examined with fluid elements to estimate the damping value. A harmonic analysis is carried out in conjunction with estimated damping value 0.3325 and also on zero damping value. The figured results are very much similar to the modeled results and a range of 1 nm to 472 nm amplitude differences between two sides of the diaphragm is observed over the entire range of the frequency in damping case.