Computational Modeling Tools for Acoustic Test Fixture Manikin Design

Hearing Protection Devices (HPDs) are critical to the audiological fitness and mission safety of military personnel. Thorough, reliable, and mission-appropriate evaluation of HPDs needs sophisticated objective methods. Some Acoustic Test Fixtures (ATFs) are available for HPD research but they have drawbacks. In this project we will develop a method of designing a new ATF manikin that is appropriate for the use in HPDs evaluations. Conventional method of designing ATF manikin relied on experimentation while the proposed method uses computational model as a design tool. This method uses Finite Element Analysis (FEA) to calculate the sound field around a manikin model, inside the ear canals and at the eardrums of the manikin. Bone conduction effects will be integrated in the model. This method will give predictions of the ATF manikin’s performance before it is constructed. This tool will determine the design paramaters required to construct the new ATF manikin. By using computational tools in the design, we reduce design time and materials’ cost. The outcome from phase II will be a complete ATF manikin system, i.e. head and torso with ear simulator system that emulates human auditory system as close as possible for the use of HPDs evaluation.