Physical Mock-up Technology for Evaluating Shape Proposals in Upstream Design Phase

This study proposes a physical mockup technology that enables users to evaluate and compare multiple design alternatives by physically interacting with them—specifically, by touching and manipulating different shapes with their hands— during the early stages of product development. The aim is to enable quantitative usability evaluation with sufficient accuracy before committing to specific design choices. To achieve this, we refined a previously proposed measurement technique that integrates webcam-based pose estimation of the mockup with infrared motion capture for finger tracking. Several enhancements were implemented, including data smoothing, which reduces jitter in the mockup’s motion trajectory, and the introduction of a supplementary camera to maintain tracking accuracy under suboptimal lighting conditions. These improvements contributed to greater overall measurement precision. To examine the practical utility of the method, we fabricated mockups of three different shapes representing spatial drawing devices and conducted a user study in which participants carried out drawing tasks with each mockup. The results demonstrated that the proposed method enables reliable and quantitative evaluation of usability.