Configuration analysis of complex multiloop linkages and manipulators

The article offers a simple and efficient method to identify all possible c onfigurations up to 29 types of basic kinematic chains containing up to fou r independent loops. Basic kinematic chains may be regarded as the basic bu ilding blocks of any complex planar linkage. Given the required inputs to a ny single or multiple degree of freedom linkage, the linkage can always be decomposed into a set of basic kinematic chains. Since the method is capabl e of identifying all possible configurations of these 29 basic kinematic ch ains, the article offers the most general and versatile method available so far for the analysis of any complicate linkage composed of these basic kin ematic chains. The method can be automated by initiating it with a structur e analysis and classification, which identifies the linkage type, the simpl est way of coupling among loops, and the complexity of the linkage, and the n activating an one-dimensional search algorithm. The search is efficient. It requires no initial guess and does not lead to an erroneous solution. Th e complexity of analyzing a multiloop linkage may be affected by the choice of the input joints. Using an alternative input joint may lead to differen t basic kinematic chains and,therefore, different level of complexity or ev en different number of configurations. The paper also shows that the number of possible configurations corresponding to a set of inputs given to a mul tiloop linkage is equal to the product of the numbers of configurations of its basic kinematic chains. (C) 1999 Elsevier Science Ltd. All rights reser ved.