The fixture layout is crucial to assure the product quality in a multistation assembly process(MAP).A well-designed fixture layout will make the final product's variability be insensitive to the fixture variation inputs.As the basis of the fixture layout design,the design criterion plays an important role in the effectiveness of a solution and the optimization efficiency.In this paper,an effective and efficient design criterion is proposed for the fixture layout with a fixed reference point(FRP)in an MAP.First of all,a state space model for the individual part's variation propagation and accumulation is developed,which is the mathematical foundation of the proposed criterion.Then,based on this model,a novel design criterion used to evaluate the performance of the fixture layout is proposed for the fixture layout with an FRP.Finally,a method extracted from the proposed design criterion is developed for quick fixture layout design.A four-station assembly process is used to validate the effectiveness and efficiency of the proposed models and methods.
