VII. Summary and "golden nuggets"

In this chapter, basic and advanced product modeling techniques are developed. These methods are cast in the light of model preparation, formal and informal models, and analytical versus physical models. They are also presented in the context of customer needs and functional modeling. This context ensures a level of consistency for all model construction activities.

After studying this chapter, it is hoped that the reader gains an appreciation for modeling and its power in product development. Modeling is the fodder that transforms concepts to the beginnings of reality, the glue that infuses our insights into the product reality, and the engineer's toolbox that we bring to bear on the challenges of product evolution. Product modeling thus should be our passion. Without modeling, our innovative ideas may be lost in the swamp of implementation and product fabrication. Other novel ideas may never be discovered due to a lack of knowledge and understanding of our product system. We should not model for the mere sake of modeling, but rather abstract a product concept to fulfill its potential.

"Golden nuggets" from this chapter include the following:

• Product models are abstractions of physical reality. As abstractions, they require creativity and perseverance, but they also simplify critical product decisions.

• Model preparation wields the product data generated in earlier phases of the development process. These data reduce modeling cycle times and help ensure valid metrics and physical understanding.

• When considering a model, there always exists a trade-off between analytical and physical models (prototypes). This trade-off, at the most basic level, comes down to model accuracy versus prototype expense, that is, "$$"!

• Informal models are abundant as product descriptions. From customer statements to graphical sketches, informal models describe the essence of what a product should be. It is the design team's challenge to formalize the informal descriptions so that repeatable and defendable product decisions may be made.

• Metrics, boundaries, and balance relationships form the core modeling concepts. These concepts transform a product concept to a parameterized form. Calibration and focused experiments extend this form to a useable framework.

• Product modeling applications add to our experience and modeling toolbox. We must ftle away this experience for future development of product models.

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