The goal of this project is to determine how the structure and mechanical properties of human auditory system affect sound transmission. We seek to use biomechanics systems methodology through both experimental measurement and computational modeling to reach this goal. There are three objectives: (1) to measure viscoelastic properties of the ear tissues (e.g., eardrum and ligaments); (2) to develop multi-field coupled analysis of the 3-D finite element (FE) model with normal and alternative middle ear structures; and (3) to correlate the 3-D FE model with acoustic-mechanical measurements on human temporal bones using laser Doppler interferometry. Four multi-disciplinary approaches are incorporated in the project: accurate geometric reconstruction of entire human ear, measurements of viscoelastic properties of ear tissues using the nanoindentation system and digital image correlation techniques, coupled acoustic-structure-fluid FE analysis of sound transmission, and measurement of acoustic-mechanical conduction through the ear with laser interferometry. The biomechanics systems methodologies in this proposal will provide a vital bridge between auditory mechanics of the ear and hearing restoration and rehabilitation. It will enhance the level of education associated with these areas and potentially improve quality of life for millions of people with hearing disabilities.
