Workshop: Design of Large-scale Complex Systems; Fort Worth, Texas; September 12, 2010

Value-Driven Design Institute, Inc., Urbana IL

Investigators

Abstract

The objective of this award will be to conduct a one day workshop with the aim of investigating whether the design of large complex systems, such as aircraft, spacecraft, or automobiles, should employ a process that allocates requirements down to each component design team, or a process that flows down objective functions. A relevant example of requirements allocation would be an automobile transmission that is required to cost less than $700 to manufacture, last more than 200,000 miles, and transmit power to the wheels with an efficiency greater than 99%. In contrast, an objective function would combine cost, life and efficiency into a scoring function and ask designers to make a transmission with the highest possible score. The objective function fits into an optimization approach which is favored by many theories of engineering design. However, requirements allocation is the standard presented in systems engineering manuals and is the process used throughout industry. The two approaches are very different, and should lead to very different outcomes. Which is better? This award will fund a workshop which will bring together world class experts in systems engineering, engineering design, and engineering optimization to discuss and compare the advantages and disadvantages of each method for the first time. Resulting from the workshop will be a research agenda aimed at significantly advancing the state of design of large-scale complex systems. Today, designs of large complex systems tend to overrun schedules, often by years, exceeding development and manufacturing budgets (by an average of about 50% in the Department of Defense and NASA). Systems are often cancelled after years of development because cost and schedule are out of control. Preliminary research suggests that most of these delays and overruns, amounting to tens of billions of dollars in losses per year, could be prevented by flowing down objective functions to enable better use of optimization in engineering. A National Science Foundation workshop in February 2010 on fundamental issues in systems engineering identified requirements versus objective functions as the most important research question in the most critical area in systems engineering today. Therefore, this workshop will critically compare the two approaches and recommend an agenda of research to develop the best process and bring it into practice. The results will be disseminated through presentations, conference papers, and journal articles.