Structure of Metamorphic Mechanisms Based on Augmented Assur Groups

Abstract

A new kind of modularized structural theory and formation method of multi-mobility metamorphic mechanisms is presented in order to form metamorphic mechanisms systematically.Planar metamorphic mechanisms are composed on the basis of developed augmented Assur group(AAG) by applying the structural forming rules of general planar mechanisms formed by Assur group(AG).The one-mobility AAG are introduced based on class II and class III AG,the structural theory and formation methodology of planar metamorphic mechanisms are proposed based on the AAG,and the basic problems such as the mobility,the metamorphic working configuration are studied.The degenerated equivalent AG of AAG in the metamorphic process and the corresponding kinematic characteristics are investigated and discussed to provide references for the synthesis of metamorphic mechanisms.Some typical spatial metamorphic group is introduced based on the concept of AAG,and the structural formation of spatial metamorphic mechanisms is given.Examples show that both planar and spatial metamorphic mechanisms can be formed by proposed one-mobility blocks systematically as general planar mechanism composed by AG.