title: Roughness encoding in human and biomimetic artificial touch: spatiotemporal frequency modulation and structural anisotropy of fingerprints.
abstract: The influence of fingerprints and their curvature in tactile sensing performance is investigated by comparative analysis of different design parameters in a biomimetic artificial fingertip, having straight or curved fingerprints. The strength in the encoding of the principal spatial period of ridged tactile stimuli (gratings) is evaluated by indenting and sliding the surfaces at controlled normal contact force and tangential sliding velocity, as a function of fingertip rotation along the indentation axis. Curved fingerprints guaranteed higher directional isotropy than straight fingerprints in the encoding of the principal frequency resulting from the ratio between the sliding velocity and the spatial periodicity of the grating. In parallel, human microneurography experiments were performed and a selection of results is included in this work in order to support the significance of the biorobotic study with the artificial tactile system.
authors.affiliation: The BioRobotics Institute, Scuola Superiore Sant'Anna, Polo Sant'Anna Valdera, Pontedera, PI, Italy. oddoc@sssup.it
authors.forename: Calogero Maria
authors.initials: CM
authors.lastname: Oddo
authors.forename: Lucia
authors.initials: L
authors.lastname: Beccai
authors.forename: Johan
authors.initials: J
authors.lastname: Wessberg
authors.forename: Helena Backlund
authors.initials: HB
authors.lastname: Wasling
authors.forename: Fabio
authors.initials: F
authors.lastname: Mattioli
authors.forename: Maria Chiara
authors.initials: MC
authors.lastname: Carrozza
mesh_terms: D000465:Algorithms; D016880:Anisotropy; D032701:Biomimetics; D015374:Biosensing Techniques / Q000379:methods*; D003878:Dermatoglyphics; D005385:Fingers / Q000502:physiology*; D005583:Fourier Analysis; D006801:Humans; D008465:Mechanoreceptors / Q000502:physiology; D015233:Models, Statistical; D011312:Pressure; D015203:Reproducibility of Results; D012371:Robotics; D012879:Skin Physiological Phenomena; D013499:Surface Properties; D013997:Time Factors; D014110:Touch; D055698:Touch Perception; D014584:User-Computer Interface