Selecting System Concept by Minimizing Cost of Part Requirement Tolerances

Abstract

At the end of a conceptual design phase, engineers choose a single (or a small set of) system concept from a large number of concept variants. In most cases, there is not enough design information to quantitatively evaluate how a final system developed from each concept would perform and cost. Thus engineers need to first perceptually evaluate and select a concept, and then design a system. On the other hand, if engineers know analytical relationships between system and part requirements, they can specify target values of part requirements such that a system achieves its target requirements. Furthermore, if engineers know how much it will cost to control part requirements within tolerances, they can minimize the cost of a system by optimizing tolerances of part requirements. This paper proposes and illustrates an approach to select a system concept when engineers know the relationship between system and part requirements, and how much it will cost to control part requirements within tolerances. Engineers choose a concept that minimizes cost.