SET-BASED DESIGN AND OPTIMIZATION.... CAN THEY LIVE TOGETHER AND MAKE BETTER TRADE SPACE DECISIONS?

Often during Product Development, externalities or requirements change, forcing design change. This uncertainty adversely affects program outcome, adding to development time and cost, production cost, and can compromise system performance. We present a development approach that minimizes impacts, by proactively considering the possibility of changes in the externalities and midcourse design changes. The approach considers the set of alternative designs and the burdens of a mid-course change from one design to another in determining the relative value of a specific design through the set-based design methodology. The approach considers and plans parallel (redundant) development of alternative designs with progressive selection of options, including time-versus-cost tradeoffs and the impact change-costs. The approach includes a framework of the development process addressing design and integration lead-times, their relationship to the time-order of design decisions, and the time-dependent burden of design changes. We also compare set-based and single point design schemes. INTRODUCTION Product Development (PD) remains uncertain and fraught with risk in development as outside factors change over time. Changing requirements during PD play havoc with program budgets, resources and schedule. Stakeholders with different concerns, constraints and changeable priorities coupled with cost and engineering technical fulfilment uncertainty impact system choices through design and development in PD programs. A Government Accounting Office (GAO) audit of Navy Destroyer Programs addressed this issue