Psychophysical evaluation of simplified haptic perception media

Detection of softness by tactile exploration in humans is based on both kinesthetic and cutaneous perception, and haptic displays should be designed so as to address such multimodal perceptual channel. Unfortunately, accurate detection and replication of cutaneous information in all its details is difficult and costly. In this paper we discuss a simplified model of haptic detection of softness (whereby only information on the rate of spread of the contact area between the finger and the specimen as the contact force increases is transmitted). We provide a thorough set of psychophysical tests, to support the feasibility (in at least some contexts) of a less complicated display of haptic features.