Characterization of Tactile Perception and Optimal Exploration Movement

The tactile sense is one of the most important senses humans process. In this study, the characterization of tactile perception and optimal exploration movement of skin were studied using an artificial finger, which is essential to the recognition of texture surfaces, the assessment of cosmetics and fabrics, and the development of intelligent robots. The vibration and friction signals during tactile perception were measured using the artificial finger and a tribometer. Eight characteristic features were extracted from the vibration and friction signals. A statistical analysis method associated with human subjective evaluation was used to compare the performance of the features in the characterization of the tactile perception. The results show that in the simulation of exploration movement using the artificial finger, the influence of exploration velocity on the tactile perception is greater than that of normal load. The sensitivity of tactile sensation is influenced by the exploration velocity. The optimal exploration velocity and normal load are approximately 10 mm/s and 1.5 N, respectively. A number of optimal features were selected. Spectral centroid, vertical deviations-1, and coefficient of friction were consistent with human tactile sensing and could characterize the perceived fineness, roughness, and slipperiness sensitively and accurately. The related mechanism was discussed.