Module approach for branch analysis of multiloop linkages/manipulators

Abstract

In this article, a module approach is developed for the branch identification of a large variety of multiloop linkages and manipulators. In this approach, a complex mechanism is first decomposed into sublinkages, called modules, with known branch and rotatability conditions. Then the effects of the interaction between modules to the branch and rotatability of the complex linkage are considered. The basic modules include all single-loop kinematic chains, Watt six-bar chains, and Stephenson six-bar chains. The variety of modules can grow as the understanding to the branch and rotatability of linkages increases. Therefore, the module approach can be regarded as a general recursive approach that is capable of recognizing the branch and rotatability condition of most of multiloop linkages and manipulators. The criterion of linkage decomposition to form modules is presented. The method treats linkages as kinematic chains and is independent of the input and fixed link conditions or linkage inversions. The method is demonstrated by the branch identification of a Watt six-bar linkage and a 10-bar linkage. The presented method is a significant advancement in the branch and rotatability studies of multiloop linkages and manipulators.