The mechanical properties and deformation of Origami structures are studied in this paper. Usually, it is a coupling problem of crease rotation and shell deformation. Here, the creases are simplified as torsional springs, whose rotational stiffness k is obtained by the experiment of compressing a creased shell. While the shells that may have large deformation are simplified as rigid plates connected by virtual creases, whose rotational stiffness is roughly expressed as bending stiffness divides width of the shell. Hence, a coupling factor C is defined to evaluate the coupling effect of creases and shells. Implementing the obtained rotational stiffnesses of real and virtual creases into the expression of strain energy, an improved Virtual Crease Method (VCM) is proposed. By analyzing the bi-stability of creased shell and Miura-Ori structure, the accuracy and convergence of this improved VCM is proved.

中文翻译：

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改进虚拟折痕法确定折纸结构力学性能

本文研究了折纸结构的力学性能和变形。通常是折痕旋转和壳变形的耦合问题。在这里，折痕被简化为扭转弹簧，其旋转刚度ķ是通过压缩褶皱壳的实验获得的。而可能有较大变形的壳被简化为通过虚拟折痕连接的刚性板，其旋转刚度大致表示为弯曲刚度除以壳的宽度。因此，耦合因子C定义为评估折痕和外壳的耦合效果。提出了一种改进的虚拟折痕法(VCM)，将得到的实折痕和虚拟折痕的转动刚度转化为应变能。通过对折痕壳和Miura-Ori结构的双稳态分析，证明了改进VCM的准确性和收敛性。