中文摘要：

分析变胞机构的工作过程与性质，归纳出变胞机构具有变化的多功能阶段、多拓扑结构、多自由度的三个显著特征。给出变胞机构的定义，讨论变胞机构的范畴和内涵，并分析容易与变胞机构相混淆的多自由度机构、机构组合、对称机构和运动限定机构等及应用场合。总结变胞机构的表达方式和变胞方法；提出变胞机构的工作阶段矩阵、变胞源矩阵和变胞矩阵的概念及构造方式，建立变胞机构在整个工作周期内各个工作阶段之间的内在联系及演变规律的数学模型——变胞方程，将变胞机构综合问题转化为多工作阶段机构型综合、变胞源机构型综合与变胞方程的求解问题，通过各工作阶段矩阵的集合运算产生变胞源矩阵和变胞矩阵，进而得到变胞源机构与变胞方式。列举几种可能的变胞方式，指出工作阶段机构与变胞源机构综合属于多解问题，给出变胞机构综合示例，讨论机构描述与型综合存在的问题，为变胞机构的研究和发展提供理论基础。

英文摘要：

The metamorphic mechanism is defined by three characteristics in multi-stage, multi-topological structure and multi-degree of freedom. The properties and boundary of metamorphic mechanism are discussed and clarified for the mechanism with multi-degree of freedom, combined symmetrical mechanisms, and kinematropic mechanisms. A way to describe a metamorphic mechanism is proposed. A new concept of the work-stage mechanism and the origin mechanism for metamorphic mechanism, which can be expressed by metrics, are presented. Meanwhile, a mathematic model of a metamorphic mechanism is set up by a metamorphic equation, which indicates the relationship among a work-stage matrix, an origin metamorphic matrix and a metamorphic matrix. The type synthesis of metamorphic mechanism can he converted into solving the group of metamorphic equations, which leads to form all work-stage matrices, an origin metamorphic matrix and metamorphic matrices. Therefore, the metamorphic mechanism, including the series work-stage mechanism and origin mechanism, is readily located by the corresponding matrices. An example, is given to demonstrate the process of the synthesis of a metamorphic mechanism. A groundwork for the theoretical basis of synthesis of metamorphic mechanisms is presented.