Validation Study of a Computer-Aided Design Augmentation Tool for Cost Estimation

While fundamentals of DFMA (design for manufacturing and assembly) are widely accepted and used in the engineering community, many CAD environments lack tools that address manufacturing concerns by providing rapid feedback about costs resulting from design choices. This article presents an experiment-based testing and validation of a rapid feedback tool that provides users history-based prediction of manufacturing time based on the current state of the design. A between-subject experiment is designed to evaluate the impact of the tool on design outcomes based on modeling time, part mass, and manufacturing time. Participants in the study included mechanical engineering graduate and undergraduate students with at least one semester of experience using solidworks. The experiment included three modeling activities and three tool conditions. Participants completed up to three sessions with different experimental conditions. Analysis of the data collected shows that the use of the design tool results in a small but nonsignificant increase in modeling time. Moreover, the use of the tool results in reduced part mass on average (both between subjects and within subjects). Tool use reduced manufacturing time in open-ended activities, but increased manufacturing time when activities focus more on mass reduction. Participant feedback suggests that the tool helped guide their material removal actions by showing the impact on manufacturing time. Finally, potential improvements and future expansions of the tool are discussed.