Dual-functional quasi-zero stiffness metamaterial for vibration isolation and impact attenuation

Abstract

Developing a multifunctional mechanical metamaterial that can handle both random vibrations and impact loads poses a significant engineering challenge. This paper introduces a quasi-zero stiffness (QZS) mechanical metamaterial that incorporates a friction mechanism to enhance vibration isolation and impact attenuation performance. The broad QZS platform of the metamaterial arises from the combined effects of flexural deformation in cosine-shaped beams, bending of inclined beams, and sliding friction. To accelerate the design process, a surrogate-based optimization algorithm combining an incremental Kriging model with a Runge-Kutta optimizer was employed. Quasi-static tests demonstrate that the metamaterial achieves over 50 % QZS platform coverage. Dynamic tests reveal its ability to isolate vibrations above 5 Hz and reduce peak impact acceleration by up to 68 %. In vibration isolation experiments on a modular airborne vehicle’s backward launch device, the QZS metamaterial reduced vibration levels (measured as RMS acceleration amplitude) by 90 % and effectively isolated random vibrations across the full frequency range of 5 to 970 Hz. This innovative design provides a robust and efficient solution for protecting airborne equipment in complex vibrational environments.