الفهرس 
AbstractOnly 14 pages are availabe for public view
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Abstract
Most automatic multispeed systems employ some kind of epicyclic gear mechanisms. For the purpose of designing such a mechanism all configurations that can provide the desired speed ratios should be generated. This generation can be processed in a systematic approach with the aid of graph theory. In this thesis, a direct enumeration process for nlink mechanism has been developed using the acyclic graph as a reliable graph representation. Initial acyclic graphs are enumerated having at least four coaxial links and at most three planet gears. A graphical enumeration approach is presented to enumerate the displacement graphs for a given acyclic graph. A new graphical code method based on an efficient priority technique has been presented for automatic evaluation of the enumerated displacement graphs to exclude open graphs, graphs having redundant links and isomorphic graphs. A computer program ?GRSYEGM? has been developed for automatic enumeration, using a graphical approach, and evaluation process using the concept of graphical code. The proposed methodology has been successfully applied for epicyclic gear mechanisms with up to 12links, having up to 9coaxial links without using the concept of adjacency matrices. As a result, complete atlas has been constructed for mechanisms up to 12links. The results of 7to10link mechanism are in agreement with previous studies in the same field. The atlas of 11 and 12link epicyclic gear mechanisms are presented for the first time using acyclic graph representation and graphical code method. An algorithm for reverse transformation process has been presented for using acyclic graph to construct the functional representation for the enumerated displacement graphs using the notation of elementary gear units. Transformation of displacement graphs with up to 12link mechanisms can be performed using the proposed algorithm. A systematic sequence for optimum selection of a desired mechanism has been introduced using a selection matrix. These results are believed to provide a useful database for the synthesis of epicyclic gear mechanisms.