Abstract: Due to many kinds of parts and tools,included in Mixed-Model Assembly Systems(MMAS),have not a reasonable layout criterian,and almostly consider workers’ physiological property and cognitive habits,which affect the assembly efficiency of MMAS,raising the layout solutions of tools and parts based on the ergonomics.The common layout solutions are regarded as research contents.Those solutions include single layer and double layers.One kinds of them has disconnected layout and corresponding layout about tools and parts.Using mouse to choose the model of tools and parts,and move them to the fixing position.The research results show that in the double layout the people’s manipulation time is lowest when those models are positioned in the best visual area,and the assembly efficiency is higher.In addition,the way of tools and parts’s corresponding layout in the best visual area has the same assembly efficiency.Lastly,checking the rationality of results of the experimentation by MMAS simulation experiment.

Key words: Mixed-Model Assembly Systems(MMAS), assembly efficiency, ergonomics, best visual area