This paper presents an efficient methodology for the systematic design of four-speed Ravigneaux-type automatic transmissions associated with the clutching sequence tables. First, the corresponding speed ratio equations of the seven-link Ravigneaux gear mechanism are derived by the concept of basic gear ratios of fundamental gear entities. Next, a methodology for the synthesis of all the clutching sequence tables of the Ravigneaux gear mechanisms is described. Then, a graph representation is proposed to embody the corresponding schematic of an automatic transmission by combining the associated clutches into the epicyclic gear mechanism. Finally, the analytic method presented by Hsu is applied to determine the numbers of teeth of all the gears for each concept. In this paper, the atlas of four four-speed Ravigneaux-type automatic transmissions has been synthesized in an efficient way.
