Identifying and Processing Undesired Functions During Conceptual Design

This paper addresses the problem of product fault anticipation and prevention during conceptual design of mechanical engineering products by introducing the concept of undesired functions as potential fault causes. The undesired functions considered in this paper are induced during solution principle synthesis and affect a product either by reducing the input of its intended functions or by producing undesired outputs, and can be processed either by determining and optimizing their distribution function, or by finding inverse, consecutive or compensation functions to them. The formal definition of the generic process of processing undesired functions bases on its subdivision into elementary steps, each step being described by its states and the according state transition. Object patterns and process patterns are adopted for the representation of the static and dynamic design knowledge respectively. The concept is verified with a product example from mechanical engineering.