Abstract: Multi mechanism structures can be obtained from one source metamorphic mechanism by selecting different constraint forms and structures of the metamorphic joints to carry out same given working tasks. A type synthesis method of constrained metamorphic mechanisms, which is aimed at to determine the constraint forms and structures of the metamorphic joints and there assemble combinations, is introduced according to the variations of the constrained forces required in the corresponding working configurations. A kind of kinematic status matrix and constraint status matrix are proposed based on the task-based matamorphic cyclogram of the source metamorphic mechanism. The equivalent resistance matrix of metamorphic joints is formed from the equivalent resistance gradient and matrix of metamorphic joints. The structural synthesis matrix is then obtained from matrix by deduceing the vecter presentasions of constraint forms and strucrtures of metamorphic joints. The type synthesis method based matrix is given in steps. The design approach is demonstrated for the powder pressing metamorphic mechanism, and the 12 typical structural matrices and the diagrams are deduced.

Key words: kinematic status;equivalent resistance;constraint form;structure of metamorphic joint;type synthesis