3D Modelling of auditory mechanics
To lead the development of enhanced ultrasonic sound detectors, we are also modelling the functional morphology of several components of the ear. This includes a large cross-species assessment of the anatomy and function of the acoustic trachea (ear canal) – which is the primary organ for sound transmission into the ear. We are measuring many aspects of the geometry of the ear canal using micro-computed tomography (µ-CT) to compare across species of different taxonomic groups and communication frequencies. This will allow us to observe how this organ has evolved to enhance the detection of ultrasonic sounds.
Using mathematical models and numerical simulations, we analysed the mechanical factors leading to the observed pressure gain inside the precise geometry of the acoustic trachea (AT) of the bush-cricket Copiphora gorgonensis. Our results demonstrate that the major factor contributing to this gain is the complex, horn-shaped geometry of the AT, which amplifies the sound analogous to an exponential horn.
Numerical investigations also enabled us to go beyond the experimental restrictions and demonstrate, for the first time, the pressure distribution inside the AT. This is a frequency dependent distribution with varying compressions/ rarefactions of the longitudinal sound wave along the tube. Check full article here. |
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