HAP02-4 不均一層構造がヒトの柔らかさ知覚に及ぼす影響
樋口夢乃，岩下耀介，永島徹也，仲谷正史，仰木裕嗣
本研究は, ヒトが不均一な柔らかさを持つ層構造物体に触れたときにどのような柔らかさ知覚するかを明らかにすることを目的とした. 層構造の異なる16 種類の触覚刺激を提示し, 実験参加者に主観的な順位評価を求めた. 本稿では，その中でも，指腹部接触部の柔軟に違いがある層構造物体（T1～T4:接触部硬，T5～T8: 接触部柔）を対象に解析を行った. 回帰分析の結果, 内部の硬い層が多いほど柔らかさ知覚の順位が有意に上昇し（硬く感じられ）, 層構造の内部の柔軟の違いがヒトの評価に系統的な影響を及ぼすことが示された. また, 一部の層構造においては柔らかい層が硬い層に挟まれていた場合，その厚さの違いで柔らかさ知覚が統計的有意に異なることも示された. 以上の結果から, 硬軟層構造の分布は柔らかさ知覚に非線形的な影響を及ぼす可能性が示唆された.
The aim of this study is to clarify how humans perceive softness when touching layered objects of non-uniform softness. Sixteen different tactile stimuli with varying layered structures were presented to participants, who were asked to provide subjective ranking evaluations. This paper focuses on the analysis of layered objects with varying softness at the fingertip contact area (T1–T4: hard contact area; T5–T8: soft contact area). Regression analysis revealed that the greater the number of hard layers present internally, the higher the perceived softness ranking increased significantly (i.e. objects were perceived as harder), indicating that differences in internal softness systematically influence human perception of softness. Furthermore, for particular layered structures, the perceived softness differed statistically significantly depending on the thickness of the soft layers when a soft layer was sandwiched between hard layers. Our results suggest that the distribution of hard and soft layers may exert a non-linear influence on human perception of softness.