A Graph-Based Method for Mechanical Product Family Modeling and Functional Tolerancing

To meet the needs for product variety, many companies are shifting from a mass production mode to mass customization, which demands quick response to the needs of individual customers with high quality and low costs. One of the key elements of mass customization is that the product family can share some modules. The multifunction nature of mechanical components necessitates designers to redesign them each time a component’s function changes. This is the main obstacle to the practical mechanical product family modeling. In this paper, a graph grammar based mechanical product family modeling method is proposed. The other issue that is studied in this paper is tolerancing, which is a critical part of the product design process because it is intimately related to a product’s quality and costs. A functional tolerance specification method, called the mirror method, is proposed to provide guidelines for the component’s datum reference frame construction and generic and uniform functional tolerance specifications.