Morphological synthesis of metamorphic mechanisms based on constraint variation

A metamorphic mechanism can be considered as a mechanism set composed by multiple kinematic chains which have the ability to be transformed sequentially from one to another following specific rules in order to meet different requirements of tasks. The process of its configuration transformation results from the variation of constraints. A special classification approach of constraints is proposed based on its characteristic of multi-configuration. The basic modes to achieve configuration transformation of metamorphic mechanisms and the design principle of metamorphic kinematic pairs are further presented. Finally, a configuration synthesis methodology of the metamorphic mechanism is proposed based on a morphological matrix. The essence of this methodology is to realize variation and coupling of mechanisms in adjacent configurations by applying metamorphic kinematic joints according to the functions, constraints, and configuration sequence. The approach is verified by developing a vehicle that can convey materials with a metamorphic driving mechanism. This study provides a fundamental theory for the design of new metamorphic mechanisms.