Displacement and force transmissibility of a quasi-zero-stiffness-based compliant metamaterial structure

It is critical to minimize vibration interference in sensitive engineering systems. A vibration isolator improves system performance and durability by reducing the transmission of vibrations between objects. However, achieving effective isolation at low frequencies with traditional linear isolators requires large static deflection, limiting their performance. Nonlinear isolators offer a solution by providing low dynamic stiffness while maintaining a high load-bearing capacity, achieving quasi-zero stiffness (QZS) characteristics. This study presents a compliant QZS (CQZS) metamaterial structure for low-frequency vibration isolation. The CQZS metastructure was designed, 3D printed, and subjected to static and dynamic analysis. Harmonic balance methods were applied to model the system, and experiments on displacement and force transmissibility validated the design's effectiveness. The results showed that the CQZS structure achieves a QZS region of 10 mm and effective isolation at 4.5 Hz. The design is simpler, lighter and more manufacturable than conventional QZS structures.