Concurrent engineering strategies for reducing design delivery time

Evolution and sensitivity characterizations provide a practical tool for identifying overlapping opportunities to reduce design delivery time. One key to reducing design delivery time is management of the information transfer between design activities. Concurrent engineering literature describes this information exchange between an upstream task and a downstream task in terms of the natural rate of information evolution in each task and the sensitivity of the downstream task to changes in upstream information.; The results of this study indicate that there are four key determinants of information evolution in a design activity: (1) Design optimization; (2) Constraint satisfaction; (3) External information exchange; (4) Standardization.; Evolution characteristics describe the rate at which information is developed in an activity. The faster the evolution of information in an activity, the less risky it is to begin a downstream activity before the fast-evolving upstream activity is finalized. However, the risk of overlapping two activities also depends on the sensitivity of a downstream activity to changes in upstream information. The key factors in assessing the sensitivity of an activity fall into one of three categories: (1) Constraint sensitive; (2) Input sensitive; (3) Integration sensitive.; There are multiple strategies available for overlapping dependent activities, including early freezing of design criteria, overdesign, early release of preliminary information, prototyping, allowing no iteration or optimization, standardization, set-based design, and decomposition. The evolution and sensitivity characteristics of activities can be used to narrow down potential overlapping strategies. The appropriateness of applying an overlapping strategy to activities with certain evolution and sensitivity characteristics is derived from the manner in which the strategy addresses information dependencies.; When overlapping dependent design activities, there are consequences to the schedule, cost and quality of the design and the subsequent construction. These consequences must be considered when deciding on an overlapping strategy. The planning framework presented in this thesis uses activity characteristics to suggest opportunities for overlapping design activities to reduce design delivery time while limiting adverse consequences, such as significant levels of rework.