Decision Support for Strategic Redesign

Researchers have paid relatively little attention to the fact that most of what is considered design is more like redesign than original design. Redesign activities are characterized by an attempt to leverage experience, knowledge, and the capital that a company has already invested into existing engineering systems. In this paper, a method for undertaking strategic redesign is proposed and explained. This method includes support for designers making decisions in redesign problems when there exist systems to be leveraged and multiple new systems to be created. In addition, strategy is introduced to the problem through the consideration that new systems may not be offered all at once, as is often assumed in product family design research. In this paper, the aim of the designer is assumed to be a creation, through redesign, of a series of new systems with desirable and distinct performance levels. In addition, a plan is required to involve as little redesign effort throughout the life of the family of systems as possible. The proposed approach is based upon the concepts of Constructal Theory and previous work to create methods for the design of mass customized families of systems. In addition, two metrics are developed to represent considerations unique to redesign as opposed to original design. These metrics for redesign effort and commonality value are utilized in the overall objective formulation for the proposed approach to redesign. Through a simple redesign scenario involving a family of universal motors, it is shown that the overall approach proposed can lead the designer towards promising redesign plans involving leveraging of existing systems, but that the constructal-inspired approach in and of itself has certain limitations when applied to redesign.