Conceptual design plays an extremely important role in the initial stage of the product development process. However, conceptual design faces challenges of high uncertainty and heavy dependence on designers' experience and intuition. There is a strong demand for establishing a methodology to quantitatively and objectively evaluate design aptitude, namely the quality of design alternatives, during conceptual design. Therefore, this research focuses on design ease and investigates what indicators can evaluate superior design alternatives. By selecting design alternatives with good design ease, i.e., design alternatives with good design aptitude, it is possible to reduce potential loads in subsequent design processes. In this research, based on functions and physical entities that model systems, as well as performance and characteristics representing both, we considered compatibility between performance pairs and formulated an equation for charge energy with respect to design alternatives centered on performance. This equation was applied as an indicator for measuring the quality of design alternatives in design alternative comparisons, and verification was conducted to determine whether it is appropriate as a judgment criterion.
SHIMADA et al. (Wed,) studied this question.