Development of a Generation Method of the Ellipse Enclosing Target Percent of Users for Generation of PCA-based Representative Cases

Abstract

The principal component analysis based generation method of representative cases has been applied in anthropometric design and digital evaluation; however, it uses a trial and error method in generating an ellipse of enclosing a target percentage (e.g., 95%) of users. This study developed a new generation method of an ellipse that statically encompasses any target percentage of users in the space of principal components. The proposed method selected the users of a target percentage from a design target population by applying normalized square distances of anthropometric sizes and   distribution. Next, an optimization algorithm was applied for the selected users to find an ellipse of mathematically enclosing them with minimum area. This study evaluated percentages of users within the ellipses formed by the proposed method under various anthropometric design conditions. The evaluation results showed that the proposed method accurately generated ellipses that statistically accommodate 90.1 ± 0.07% (mean ± SE), 94.9 ± 0.06%, and 97.8 ± 0.05% for 90%, 95%, and 98% of target percentage.