Mimicking Human Hearing with Topologically Optimized Structure

The remarkable auditory capabilities of human ears have inspired the development of bio-inspired acoustic sensing technologies. In this study, a topology optimization problem is formulated to replicate the hearing profile of the human ear and is solved using a gradient-based optimization method. To ensure manufacturability and mesh independence, a density filter is employed to eliminate gray scale transitions between solid and void regions. The objective function is defined to minimize the error between the human's Head-Related Transfer Function (HRTF) of a reference structure and the designed domain in specific frequencies and directions. Numerical simulations demonstrate that the optimized structure exhibits similar acoustic characteristics and spatial directivity to that of the ideal human ear at the designated frequencies. The proposed structure and optimization method show great potential for applications such as 3D audio rendering, hearing- aid design, and sound source localization.