Abstract: The structural characteristics of both planar and spatial kinematic chains are described by proposing a new topological presentation, which is called loop-link-joint-matrix (shortened as JLL), based on independent loop(s) of kinematic chains. JLL has fewer elements compared with common used structural characteristic matrix and characteristic polynomial in the literature and JLL can be easy formed. JLL is applied to identify isomorphism of both planar and spatial kinematic chains and mechanisms with all kinds of joints by comparing the corresponding elements of JLL in rather simpler way. Method, procedures and flow chart of identification are presented. It is also capable of studying the inversion problems of kinematic chains and mechanisms by JLL. Examples of both detecting isomorphism and inversion problems are given.

Key words: Kinematic chains Isomorphism Identification Inversions