A biomimetic fingerprint improves spatial tactile perception


L. Cramphorn, B. Ward-Cherrier, and N. Lepora, “A biomimetic fingerprint improves spatial tactile perception,” IEEE Robotics and Automation Letters, 2017.


The fingerprint is a morphological aspect of the human fingertip that has interesting implications for our sense of touch. Previous studies focused on how the fingerprint affects the perception of stimuli that excite high temporal frequencies, such as for texture perception. These studies also only add papillary ridges to their sensors. Here we endow a biomimetic sensor with both papillary ridges (fingerprint) and a dermal stiffness contrast (stiffer intermediate ridges), and assess the impact on localisation perception accuracy. The sensor is based on a novel modular version of a 3D printed tactile sensor (TacTip). Tactile data was collected with these tips on 9 stimuli with varying curvature. The location perception acuity of three tips (smooth, fingerprint, and fingerprint (cores)) were compared with a probabilistic classification method. Finding that both fingerprinted tips increase the perceptual acuity of small spatial scales. Interestingly the fingerprint variant had poorer accuracy than the smooth tip for larger spatial scales; however, adding cores to enhance the dermal stiffness counteracted the degradation of accuracy. This supports the theories that the fingerprint aids the classification of edges and smaller spatial scales, and demonstrates that the addition of a fingerprint to an artificial tactile sensors improves its acuity.

Last updated on 01/23/2017