Point-Based versus Set-Based Design Methods for Robust Ship Design
By Dr. Alexander Gray, Dr. Douglas Rigterink, & Nicholas Mullican
Set-based design has grown in popularity and status thanks to several successful implementations of the design method within the Navy. Future ship, submarine, UUV, and USV programs are now considering employing the set-based design method. However, set-based design is still viewed by some circles of the naval design community with uncertainty, negativity, and as primarily a buzz word. The goal of this paper is to educate readers on the set-based design method and to discuss the pros and cons of set-based design in the context of a notional ship design study. Two design teams set out to design a notional surface combatant given the same set of design requirements; one team using the set-based design method and the other following the traditional point-based design method. The design study also included two mid-design requirement changes to test the robustness of the respective design methods. At the conclusion of the design study, the set-based design process proved to be more robust and the design team was able to develop a lower cost and lower risk ship design when compared to the point-based design team. This paper begins with a short overview of the set-based design method compared to point-based design method, followed by an outline of the requirements for the notional ship design study. Details on how each team applied its respective design method to tackle the concept ship design study are summarized. The role of design tools to aid in the ship design process is also discussed. The paper concludes with insights into how and why the set-based design team prevailed.