Design-Driven Framework for the Complexity Quantification of Mechanical Components

From large aerospace assemblies to micro-scale medical devices, modern engineering systems are expected to comply with an ever-increasing number of requirements. This increase in expected system performance and -ilities inevitably raises system complexity, which in turn drives up costs, extends development timelines, and complicates system integration, testing, and maintenance. While complexity budgeting -similar to cost or mass budgeting- could help manage these demands, no standardized approach to characterize, quantify, and manage system complexity is currently available. This paper introduces a framework to assess the complexity of mechanical components by evaluating their shape, mass, size, tolerances, material, and interdisciplinarity with respect to standard regulations, manufacturing solutions, and handling processes. Shape was identified as the main complexity driver and is evaluated based on mesh size. The five other factors are independently assessed as weights to yield the final complexity score. The framework was validated using four representative components: an automotive V8 engine block, NASA's Ingenuity rotorcraft's blade, a kayak hull, and a ceramic cup which respectively received complexity scores of 103.05, 17.42, 13.91, and 7.90. The proposed framework describes a solution-neutral complexity quantification of mechanical components, but its thresholds and weights can be tailored to an organization's specific capabilities for a customized complexity assessment that aligns with unique operational contexts.