1. A computer-implemented method for analyzing a mechanical system, the method comprising: using a computer program product executed by a processor associated with the computer, importing from an engineering design software program data related to a mechanical assembly; using the computer program product, receiving a selection of one or more sub-assemblies of the mechanical assembly; receiving user input comprising a selection of two or more points associated with the one or more sub-assemblies, and of one or more connections of the points, to form a user-defined sublinkage; accessing a library of a plurality of predefined sublinkages corresponding to predefined configurations of particular linkages and connection points between the linkages; matching, automatically by at least one computer processor, the user-defined sublinkage to a predefined sublinkage contained in the library of the plurality of predefined sublinkages; determining, by the at least one processor and based on the matching predefined sublinkage, a plurality of three-dimensional model solutions of the user-defined sublinkage, wherein each of the determined plurality of model solutions of the user-defined sublinkage includes the same linkages and connection points between the linkages but different positions and orientations of the linkages; presenting the three-dimensional model solutions to a user; and receiving a selection of a model solution from the presented three-dimensional model solutions.