Bionic design and numerical studies of spider web-inspired membrane-type acoustic metamaterials

Being demonstrated to have excellent soundproof properties, Membrane-type acoustic metamaterials (MAMs) have been extensively investigated. Inspired by a spider web, this study designed a bionic MAM by combining a membrane, frame, and set of resonators. The computational and experimental results show that the bio-inspired model has a 19 % reduction in mass and 61 % expansion in bandwidth. Furthermore, we investigated the laws of three design parameters— membrane shape, resonator position and model size—of the structure soundproof performance and analyzed its multi-state anti-resonance modes. The results show that the round model performed better than other two square models on soundproof performance. The best soundproof performance was achieved when the resonator was positioned at a radius ratio of 0.54. The model still has a substantial noise reduction at reduced size but the risks of failure when size increases. These studies will generate fresh insight into producing more efficient low-frequency sound insulation materials.