标题： 负伸长率超材料的被动振动隔离特性 显示英文标题

标题： Passive Vibration Isolation Characteristics of Negative Extensibility Metamaterials

摘要： 负延伸性指的是具有异常现象的机械超材料类别，即系统在扩展时会收缩。 此类系统的动态分析对于探索振动隔离特性至关重要，是本研究的主要焦点。 受布拉埃斯悖论的启发，该力学模型结合了耦合可调非线性弹簧刚度特性（应变硬化和软化），当超过一定位移阈值时会发生交替。 这种刚度切换机制利用反向弹跳不稳定性现象，实现了低频被动振动隔离。 通过时间域和频率域图示对由刚度切换机制产生的振动隔离特性进行了研究。 此外，使用三维参数空间可视化了刚度切换机制与各种系统参数之间的关系。 通过与现有双稳态系统的比较，评估了所提出系统的有效性，结果表明其在隔离高幅值振动方面表现出优越性能。 所提出的机制增强了对多稳态机械超材料中关键结构元件动态行为的理解，为创新自适应设计提供了见解和机会。 显示英文摘要

摘要： Negative extensibility refers to the category of mechanical metamaterials having an unusual phenomenon where the system contracts upon expansion. The dynamic analysis of such systems is crucial for exploring the vibration isolation characteristics, forming the prime focus of the present study. Inspired by the Braess paradox, the mechanical model incorporates coupled tunable nonlinear spring stiffness properties (strain hardening and softening), which alternate when a certain displacement threshold is exceeded. This stiffness switching mechanism facilitates low frequency passive vibration isolation using the phenomenon of countersnapping instability. The vibration isolation characteristics resulting from the stiffness switching mechanism are investigated using time and frequency domain plots. Furthermore, the relationship between the stiffness switching mechanism and various system parameters is visualized using a three dimensional parametric space. The efficacy of the proposed system is evaluated by comparing it with the existing bistable systems, revealing superior performance in isolating high-amplitude vibrations. The proposed mechanism enhances the understanding of dynamic behaviors in critical structural elements for multistable mechanical metamaterials, providing insights and opportunities for innovative adaptive designs.