Evaluating design factors influencing sheet metal bending effort

Understanding how geometric design choices will reflect on manufacturing effort remains a critical challenge for sheet metal working companies. This study proposes and experimentally evaluates a set of geometric features to quantify the bending effort from the design stage. Designs with systematically varying geometric traits, including benchmark parts from prior studies, were manufactured by two different operators using the same sheet thickness and material type. Bending times were extracted using the machine’s programmable logic controller (PLC) logs and evaluated against the mean bending duration and a failure-integrated performance metric: the estimated mean production time for a successful full batch. Ordinary least squares (OLS) regression fit indicates that the proposed design features can explain 88% of the variance in mean production time. Proposed features: Box profiles with perpendicular bend corners, non-parallel bends, asymmetry, flange direction variability, and narrow gauging edges were shown to increase the bending effort. Comparative analysis between part pairs reveals how these features contribute to the effort, with statistical significance validated using one-way analysis of variance (ANOVA) and Welch’s t-tests. The results demonstrate the quantitative relationship between the proposed geometric design features and bending effort, providing a foundation for design for manufacturing research and future integration of human-centric computer-aided design and manufacturing (CAD-CAM) tools.