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arXiv · 2107.02084

Artificial SA-I and RA-I Afferents for Tactile Sensing of Ridges and Gratings

Nicholas Pestell·Thom Griffith·Nathan F. Lepora
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Abstract

For robot touch to converge with the human sense of touch, artificial transduction should involve biologically-plausible population codes analogous to those of natural afferents. Using a biomimetic tactile sensor with 3d-printed skin based on the dermal-epidermal boundary, we propose two novel feature sets to mimic slowly-adapting and rapidly-adapting type-I tactile mechanoreceptor function. Their plausibility is tested with three classic experiments from the study of natural touch: impingement on a flat plate to probe adaptation and spatial modulation; stimulation by spatially-complex ridged stimuli to probe single afferent responses; and perception of grating orientation to probe the population response. Our results show a match between artificial and natural afferent responses in their sensitivity to edges and gaps; likewise, the human and robot psychometric functions match for grating orientation. These findings could benefit robot manipulation, prosthetics and the neurophysiology of touch.

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Nicholas Pestell, Thom Griffith, Nathan F. Lepora. 2021-07-05. Artificial SA-I and RA-I Afferents for Tactile Sensing of Ridges and Gratings. https://doi.org/10.1098/rsif.2021.0822

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