An analytical model for a general Star-4 system, having different ligament lengths, angles, and ligament thickness, is derived using Castigliano's second theorem. The analytical model is validated through finite element analysis and experimental work. The results obtained show that, depending on the parameters used, the general Star-4 system can show a wide range of Poisson's ratios with the potential of obtaining giant negative Poisson's ratios (in the order of −8) for certain conformations. The wide range of Poisson's ratio is explained in terms of the different geometrical conformations obtainable by the system, where the star-ligaments can also describe rhombi, irregular octagons, rectangles, and accordion-like systems, together with changes in the deformation mechanism due to variations in parameters. For example, if one set of star-ligaments is much thicker than the other, the deformation of the star would be akin to that of the hexagonal reentrant unit cell.

中文翻译：

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一般 Star-4 结构的拉胀行为

具有不同韧带长度、角度和韧带厚度的一般 Star-4 系统的分析模型是使用卡斯蒂利亚诺第二定理推导出来的。分析模型通过有限元分析和实验工作得到验证。获得的结果表明，根据所使用的参数，一般的 Star-4 系统可以显示出广泛的泊松比，并有可能获得某些构象的巨大负泊松比（-8 的数量级）。泊松比的广泛范围是根据系统可获得的不同几何构象来解释的，其中星状韧带也可以描述菱形、不规则八边形、矩形和手风琴状系统，以及由于变形机制的变化参数的变化。例如，