A tunable metamaterial using a single beam element with quasi-zero-stiffness characteristics for low-frequency vibration isolation

Quasi-zero-stiffness (QZS) isolators exhibit high-static and low-dynamic stiffness without sacrificing the load-bearing capacity and with the ability to shield the vibration in low-frequency ranges. Most of the current designs possess QZS property using a combination of positive stiffness element with negative stiffness element, increasing the complexity of the model. In the present research, a single-element mechanical metamaterial is tailored to obtain the QZS property. The building block consists of a single elastically-deformed beam, and the static results of the 3D-printed metastructure demonstrate QZS behavior. A mathematical model is developed for studying the nonlinear behavior of the proposed model, and the dynamic equation is solved using Harmonic-Balance method. Further, an experiment is performed to confirm the vibration isolation capability of the proposed model in low-frequency ranges. Stability analysis is performed mathematically using the perturbation analysis. The QZS mechanism obtained here solely depends on the flexible beam's geometrical configuration, hence making the design strategy material independent.

Automated summary

In this research, a single-element mechanical metamaterial is designed to achieve quasi-zero-stiffness (QZS) property, which eliminates the need for a combination of positive and negative stiffness elements, simplifies the model, and improves load-bearing capacity. The QZS mechanism is solely based on the geometrical configuration of the flexible beam, making it material independent. Mathematical modeling, Harmonic-Balance method, and experimental validation confirm the vibration isolation capability of the proposed model in low-frequency ranges. Stability analysis is also performed.