A novel lever-type elastic metamaterial model for low-frequency wave attenuation

Abstract

Elastic metamaterials have received extensive attention due to their proven track record in wave attenuation. In this study, a novel one-dimensional lever-type elastic metamaterial model is designed to achieve low-frequency wave attenuation by introducing an adjustable lever mechanism in a conventional mass-spring resonator. The dispersion relation and effective mass expression of the proposed metamaterial are theoretically derived. Then, the band structure characteristics and the effect of parameters on the band gap are analyzed in detail. The results show that by selecting appropriate lever ratio and initial rotation angle, a low frequency band gap can be obtained and the wave attenuation capability within the band gap can be enhanced. Finally, the dynamic response of the proposed structure is calculated by direct numerical integration method to verify the analytical results. Furthermore, the application potential of the proposed elastic metamaterial in shock wave attenuation is demonstrated by analyzing the spatial propagation of wave packets along the proposed structure. This study provides a meaningful reference for the design of other tunable elastic metamaterials to attenuate waves.