Tactile Flow and Haptic Discrimination of Softness

Haptic perception involves both cutaneous perception, through mechanoreceptors lying on the skin, and kinaesthetic perception mediated by the position of the fingers. Analogously, artificial devices should replicate both these perceptual channels, as well. While kinesthetic information is satisfactorily replicated by current technology, cutaneous information is still a challenging task to be provided. In order to comply with this goal, a computational model of perceptual flow, inspired to established models for vision, has been recently extended to the tactile domain. It has been shown that tactile flow encodes important information on relative motion and segmentation of tactual scenes. In this paper we illustrate how previous results on the ”contact area spread rate” with softness detection can be conveniently explained in terms of integral of tactile flow over the contact area.