Analysis and mimicking of contact vibrations, induced by touching isotropic surface textures

The sense of touch is the less comprehended among the five senses. The vibrations induced by the sliding contact between the finger and a surface stimulate the mechanoreceptors and play a fundamental role in the perception and the discrimination of surfaces, particularly for the finer textures. In this work, the Friction-Induced Vibrations (FIV), generated by finger scanning of surfaces with random isotropic topography, are measured and analyzed to identifying different features of the vibration spectra and their role in the surface discrimination. To reproduce and artificially mimicking the tactile sensation of the surface textures, the measured vibrations are then reproduced by means of a tactile device, named PIEZOTACT, based on an Electro-Active Polymer (EAP) piezoelectric actuator. Discrimination tests on real surfaces and on the mimicked ones by the PIEZOTACT are conducted to evaluate the ability to discriminate textures by the sole Friction-Induced Vibrations reproduced by the tactile device.