Add to the list of things robots now do better than humans: feel. Researchers at the U. of Southern California’s Viterbi School of Engineering have designed a robot finger that can outperform humans in the basic yet complex sensory task of touching. Their robot finger, equipped with a novel tactile sensor technology, is better at identifying and distinguishing between different materials and textures than human beings are.
Like most breakthroughs of this nature, the BioTac sensor (that’s its commercial name) is part hardware ingenuity, part software solution. The finger itself is very much like a human’s. A flexible, spongy skin complete with ridges (like a fingerprint) is stretched over a liquid filling. As it slides over a surface, the skin vibrates in ways that are distinctly tied to the texture of the material it is touching. A hydrophone inside the core of the finger picks up these vibrations and uses them to distinguish between materials.On the software side, the researchers also strove to mimic the human process for evaluating textures. When humans attempt to identify something by touch, there are a huge number of exploratory movements he or she can choose from. Maybe a person prefers to rub certain kinds of textile materials between two fingers to pick up subtleties of cloth texture, while he or she appraises glassy or metallic surface differently. All this comes from prior experience with these materials or with similar materials.