Using Set‐Based Design to Inform System Requirements and Evaluate Design Decisions

Abstract

Set‐Based Design (SBD) is a concurrent engineering technique for system design and systems analysis and an alternative to Point‐Based Design (PBD). System analysts perform Tradespace Exploration in early system design to assess requirements and identify affordable designs that meet complex stakeholder requirements. This paper demonstrates the use of SBD to inform system requirements and evaluate design options. We use an Unmanned Aerial Vehicle (UAV) case study with an integrated Model‐Based Engineering framework with SBD to identify potential designs, assess design feasibility, inform requirements, and evaluate feasible designs displayed in sets with common design choices. We use SIP Math from Probability Management© to explore 100,000 potential systems design concepts and architectures in near real‐time. Using our integrated framework with 47 physics‐based models and 11 requirements, we found that only 2.5% of the potential designs were feasible. We validate that SBD finds the efficient frontier in the value versus cost tradespace. We use SBD to inform systems requirements by identifying the number of potential feasible designs in the tradespace for each requirement or combination of requirements. Relaxing the requirements can increase the percentage of feasible designs. Constraining or relaxing 4 of the 11 requirements significantly affected the feasible design space. We also use SBD to evaluate design options, which provides useful information for system designers. We conclude that SBD provides a more comprehensive tradespace exploration than PBD and useful insights into requirement development.