Impossible objects robust against viewpoint motion and their applications

2020 Fiscal Year Final Research Report

• Project/Area Number: 18K19827
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 61:Human informatics and related fields
• Research Institution: Meiji University
• Principal Investigator: Sugihara Kokichi 明治大学, 研究・知財戦略機構(中野), 研究推進員 (40144117)
• Project Period (FY): 2018-06-29 – 2021-03-31
• Keywords: 不可能立体 / 立体錯視 / 錯視の安定性 / 変身立体 / 曲率の誤認 / 変身タイリング / 道路カーブ / 動的立体錯視

Outline of Final Research Achievements

We found two main factors of impossible object illusions that do not disappear even if we change our viewpoints. The first factor is that the illusion-inducing properties belong to 3D shapes instead of 2D appearances. This factor works effectively in "deformable object illusion" and "ambiguous tiling illusion." The second factor is that the object is composed of 3D structures and 2D pictures in a mixed way so that picture parts also appear to be 3D. This factor works in "height reversal illusion." For road illusion, we found that the sharpness of a curve is misperceived both if the curve accompanies the change of the road slope and if the driver does not notice this slope change. This result suggests the importance of the road sign telling that the next curve is sharper than it appears, instead of recommending to decrease the speed. We summarized our results in a form of a family tree of impossible objects, which can tell why illusion occurs for each group of impossible objects.

Free Research Field

数理工学

Academic Significance and Societal Importance of the Research Achievements

視点を動かしても起き続ける新し立体錯視の種類を見つけ、その発生メカニズムを明らかにすると同時に、その作品例を多数創作した。これらは、「見る」という日常の行為の中に不思議さが残っていることを端的に示す材料となり、全国の科学館、児童館、美術館での視覚について考える特別展などでたくさん取り上げられた。道路カーブの鋭さの誤認メカニズムの解明によって、ドライバーへの注意喚起の方法として、今までの「スピードを落とせ」に加えて、「前方のカーブは見かけより急です」という新しいタイプのメッセージの有効性を示唆することができた。