An acoustic mitigating headgear consisting of plate-type metamaterials

The acoustic environment in urban areas has attracted increasing attention, particularly in regions exposed to heavy traffic. The purpose of the study was to develop a personal quiet zone near the ears using metamaterial-made acoustic headgear. Several headgear designs employing plate-type acoustic metamaterials were proposed with various configurations. The performance of a single sandwiched unit cell, composed of coupled Helmholtz resonators made of dual membranes, was evaluated through numerical modal simulation and validated by waveguide experiments. Furthermore, polygonal metamaterial components were assembled into shapes derived from Archimedean solids to construct headgear capable of generating localized quiet zones. The effectiveness of the headgear was assessed in both anechoic and reverberation chambers, representing quiet and noisy environments. The results demonstrate three key findings. Firstly, all five configurations exhibit bandgaps covering exceeding 1000 Hz, with the widest reaching 2292 Hz and achieving insertion loss values greater than 5 dB. Secondly, semi-enclosed designs provide insulation starting near 1000 Hz, with some extending to lower frequencies. In particular, the “big with face shield” configuration achieved the lowest bandgap from 708 Hz and effectively covered the dominant traffic noise range near 1000 Hz. The addition of a face shield further enhance their performance. Finally, the variety of configurations enables adaptation to diverse application scenarios. Their lightweight construction, compact size, and geometric flexibility indicate a strong potential to meet customized requirements in noise mitigation. • Waveguide experiment validated simulation approach for insertion loss prediction of large individual components. • Lightweight headgears developed using effective double-membrane plate-type acoustic metamaterials. • Effective attenuation of traffic noise achieved by broad bandgaps. • Reconfigurable headgear configurations target multi-frequency noise.