Surface Illusions

 

The work presented here aims to enrich material perception when touching interactive surfaces. This is realized through simulating changes in the perception of various material properties, such as softness and bendability. The thereby created perceptual illusions of surface changes are induced using electrotactile stimuli and texture projection as touch/pressure feedback. A metal plate with an embedded electrode was used to provide the user with electrotactile stimuli when touching the surface with a finger that is also equipped with an electrode. The distortion of material textures projected on the touched surface was used to visually simulate surface deformations. We show through an experiment that both, electrotactile and visual feedback can induce the illusion of surface deformation when provided separately. When tactile and visual touch feedback is presented at the same time, the perception of surface changes does not increase compared to just using one feedback modality only.