Modularity in Product Design for Manufacturability

This paper discusses the relationship between modular products and manufacturing. The relationship is based on an expanded definition of modularity which incorporates the potential of modularity based not only on end uses of a product but also on the manufacturing processes. By incorporating this expanded definition of modularity, called manufacturing modularity , into product development, a more robust product modularity can be achieved. Modularization, due to the functional independence it creates, has been called the goal of good design. Industry has made an effort to modularize products to be flexible to the needs of end users and marketing. This effort has led to the creation of product families. Occasionally, modules are created with some aspects of production in mind. However, this modularization is done without fully understanding the implications of the design. Although often yielding highly functional products, once the entire manufacturing process is accounted for, this unstructured modularization often leads to costly redesigns or expensive products. In addition, the unstructured modularization makes the process difficult to repeat if it is successful and difficult to avoid if it is unsuccessful. Modularity requires maintaining independence between components and processes in different modules, encouraging similarity in all components and processes in a module, and maintaining interchangeability between modules. Modularity with respect to manufacturing necessitates understanding the various manufacturing processes undergone by each attribute of each component. This paper presents a basic methodology for creating manufacturing modules. These modules decrease manufacturing costs, decrease lead time, and strengthen product families. A design methodology is developed which prevents a cascade of product design changes due to changes in manufacturing processes and supports agility in the face of changes in manufacturing processes. The methodology and its elements are highlighted in the redesign of an electric coffee maker.