JME_V3_N2_RP6 Mubina Shekh Ali Hasan R.A. Khan A.A.S. Mohd Journal on Mechanical Engineering 2249 - 0744 3 2 39 48 Degree of Freedom (DOF), Kinematic Chains (KC) & Distinct Mechanism (DM), JJ Matrix, Weighted Distance Matrix (WDM), Structural Invariants There are numerous methods available for the identification of isomorphism and distinct mechanism. According to various researchers their method is easy to use and reliable but every method has some limitations. In this paper author studies, existing methods which are already available in literature. And an effort is being made to compare some important methods from the point of view of various attributes like reliability, simplicity, capability, time and applicability etc. to detect the best method for identification of isomorphism and inversions (distinct mechanism) of a kinematic chain. These methods are based on rating according to above attributes and on a scale of one to five. Highest ratings among these methods are considered as best method. February - April 2013 Copyright © 2013 i-manager publications. All rights reserved. i-manager Publications http://www.imanagerpublications.com/Article.aspx?ArticleId=2215