Perceptual biases in tactile flow

In this paper we report on results of a psychophysical experiment in which the optic illusion of Ouchi is reproduced in the tactile domain. In the vision field, when eyes scan over a texture grid, consisting of two rectangular checkerboard patterns oriented in orthogonal directions, the inset pattern appears to move relatively to the surrounding grid. A simplified 3D version of this pattern was realized and a group of subjects were asked to touch it while it was vibrating. Outcomes of this experiment are discussed in terms of tactile flow and the related aperture problem.