This paper presents a naval ship Concept and Requirements Exploration (C&RE) process and associated design tools that were developed considering the necessity to understand the relationship between cost, effectiveness, and risk for feasible designs before requirements are set and baseline design concepts are selected. This process has evolved over more than 15 years of research and collaboration and begins with a clear and quantitative definition of mission need, capability gaps, goals, thresholds, concept of operations, and constraints. It includes: quantitative models and metrics for cost, effectiveness and risk; tools for design space exploration, screening and refinement; a synthesis model for integration of hull form, deckhouse, combat systems, and HM&E systems; and tools to assess ship balance and feasibility. A multi-objective optimization is used to search the design space for non-dominated feasible concepts. Significant developments and changes are being made to replace expert opinion-based effectiveness models with physics and operational analysis-based Operational Effectiveness Models (OEMs), and to include survivability analyses and lethality analyses explicitly in these OEMs. In order to accomplish this, many synthesis model parametrics have been replaced by calculations based on a 3-D hull and superstructure geometry that includes primary subdivision, preliminary general arrangements, and the locations and basic architecture of mission-critical systems. We have also included a more complete manning model that considers maintenance (equipment and compartment), operations, and will ultimately consider damage control task analysis. The critical importance of considering survivability early has been the primary driver for these changes. This paper emphasizes the planning and implementation of these most recent changes in our evolving process. This is our introductory overview paper and it will be followed by a series of papers addressing specific methods and submodels with an emphasis on survivability.
