Effect of Texture on the Perception of Axis of Rotation of Rotating Panels

Planar, orthogonal structures are very common in man-made environments. We often interact with rectangular structures such as doors and walls in our environment. When a rigid, rectangular structure rotates about a pivot axis, there is information in the ambient optic array, that specifies what the rotating structure affords to the observer. Previous studies identified optical information available to detect the position of the axis of rotation of rotating panels and the current study empirically verifies that observers are sensitive to that information. In one desktop-based experiment and two immersive virtual reality experiments, participants indicated the location of the pivot axis of a rotating panel, as quickly and accurately as possible. Factors like texture on the panel, texture on the background, position of axis of rotation, and linear velocity of the farthest edge from the pivot axis were manipulated. Results indicate that participants were sensitive to texture information associated with invariants specifying the axis of rotation. The results suggest the importance of texture information in vision and how optical invariants help us to directly perceive affordances in built environments.