Invention by Design
by Ed Buch, CSI, CCS, AIA

The title of the book, Invention by Design, “How Engineers get from Thought to Things,” by Henry Petroski, (Harvard University Press, 1996, 242 pages), fits the subject matter precisely. Using a series of case studies, Petroski brings the complex process of engineering design to life. His prose will grab you and hold the interest of just about anyone with an ounce of curiosity about the manmade world around us.

Petroski, the Aleksandar S. Vesic Professor of Civil Engineering and Professor of History at Duke University, is the author of twelve books on engineering, design, and technology. He combines a keen sense of the appropriate level of detail with the ability to distill complicated subject matter to clear and simple explanations. In the process he tells fascinating stories. Each chapter emphasizes an aspect of the sometimes complex interplay of factors that can affect design: technical, functional, social, economic, or political. Engineering design is, in the end, a balance of these competing influences.

Invention by Design uses the development of a variety objects to illustrate the nature of invention. From the prosaic paper clip to the amazingly complex aluminum pop-top soda can, to bridges and buildings. Even the simplest objects can embody engineering design principals.

The development of the paper clip is used to illustrate how subtle design changes, introduced to simplify manufacturing and reduce cost, can have an adverse consequence on performance. The chapter on the history of zippers, (“slide closers” is the generic term used to include Velcro and zip lock bags), highlights the development of a device that came about as the direct result of a need to solve a problem. The importance of manufacturing as a determinant in design is also discussed.

Chapter 5 explains how the choice of materials, aluminum over steel in this case, and then how selecting the right weight of aluminum affected the design of the pop-top beverage can. This example is also used to illustrate how environmental factors came to bear on the redesign of the pop-top tab so it stays attached to the can.

The one important area he stays out of completely in all ten chapters is the visual aspect of the design. It’s almost as if aesthetics has no place in the process. While as an engin eer he may think he’s not qualified to comment on the aesthetics in a particular instance, to ignore it all together leaves a large gap in the complete story of the design of almost everything. The appearance of an object is, in many cases, the most important aspect differentiating one device or product from another.

Petroski is an author with the ability, to say nothing of the interest, to write on a wide variety of subjects. He is the author of an entire book on the history of the pencil, for example. “Entertaining” doesn’t seem like an appropriate adjective to use in describing technical books, but his are. His most recent book, Pushing the Limits, uses the same case study approach to present in depth looks at a collection of more recent engineering projects. But that’s another story.

Ed Buch is an architect in the Los Angeles office of Leo A Daly. A Nebraska native, he has worked in Los Angeles since 1988. Prior to that, he worked in Omaha and Lincoln, Nebraska, and 5 years in Riyadh, Saudi Arabia. He has been member since 1981, and is currently an Institute director from the West Region, CSI.