Lamina Emergent Mechanisms (LEMs) are an important part of compliant mechanisms, and origami technology can fold simple two-dimensional planes into complex three-dimensional geometries. This paper introduces a design method to achieve large deformation of Lamina Emergent torsional (LET) joints in multiple directions through origami technology. A Foldable mortise-tenon structure (FMTS) is proposed to make permanent creases in origami-based mechanisms. The influence of structural parameters of the FMTS on its maximum deformation and maximum stress under tension is studied. Based on the proposed method and structure, a two degree of freedom Lamina Emergent Joint (2DOF-LEJ) is designed. The structural design, equivalent stiffness analysis, and finite element analysis (FEA) of the 2DOF-LEJ are carried out. Experimental tests verify the effectiveness of the proposed method and FMTS on the prototype. Finally, some applications of the proposed method and FMTS in origami-based mechanisms are discussed.

层板出现机制（LEM）是顺应性机制的重要组成部分，折纸技术可以将简单的二维平面折叠为复杂的三维几何形状。本文介绍了一种通过折纸技术实现多个方向的椎板紧急扭转（LET）大变形的设计方法。提出了一种可折叠的榫眼结构（FMTS），以在基于折纸的机制中产生永久性折痕。研究了FMTS结构参数对其在拉力作用下的最大变形和最大应力的影响。基于所提出的方法和结构，设计了一种两自由度椎板紧急关节（2DOF-LEJ）。进行了2DOF-LEJ的结构设计，等效刚度分析和有限元分析（FEA）。实验测试验证了所提出的方法和FMTS在原型上的有效性。最后，讨论了所提出的方法和FMTS在基于折纸的机制中的一些应用。