The role of features in the implementation of concurrent product and process design

Abstract

There has recently been much literature written concerning the subject of features in the context of design and manufacturing automation. In particular, features have been hailed as the savior by which the long separated disciplines of design and manufacturing may be reunited. Such prophecy has subsequently elevated the term features'' from a stature of relative insignificance to the distinction of being a bonafide CAD/CAM vernacular. As unfortunately seems to be the case with most technological buzzwords,'' however, there has been much confusion concerning the significance of this concept. In particular there has been a general misunderstanding over the role features should play in the achievement of concurrent product and process design. It has been suggested that those features used to design a part should also be used to guide planning for the production of that part. While elegant in its simplicity and certainly feasible for selected cases, this notion tends to ignore the context-dependency of most features and does not generally scale to the real world. This paper argues that while features are integral to the automation of experience-based reasoning in design and manufacturing, their role in the integration of these activities is relatively minor. This argument is made through the use of real-world case studies that illustrate the manufacturing implications of minor variations in feature decompositions. It is further argued that the inevitable consequence of this argument in the context of concurrent product and process design is an intensified need for automatic feature recognition. 21 refs., 11 figs.