Kinematic Characteristics and Classification of Geared Mechanisms Using the Concept of Kinematic Fractionation

Abstract

A methodology based on the concept of kinematic fractionation for the revelation of kinematic characteristics and classification of geared mechanisms is presented. It is shown that structurally nonfractionated geared mechanisms can be considered as the combination of kinematic units (KUs). Each KU is considered as the basic motion transmission module inside a geared mechanism. Admissible connections of KUs are identified according to the structural characteristics of one- and two-degree-of-freedom geared mechanisms of up to four KUs. Graphs in the atlas of the geared mechanisms are classified based on the configurations of KUs. Such configurations are then used to construct possible propagation paths of motion via the assignments of input and output links. Since the propagation paths can be modeled by the control block diagram problems, the kinematic relations between input and output links are formulated to gain matrices. According to the types of entities in a gain matrix, various kinematic behaviors are disclosed. It is believed that such kinematic characteristics can be readily transformed into the functional requirements, and the synthesis of geared mechanisms of up to four KUs can be accomplished much easier.