Imparting the sense of touch to artificial skin for both robotics or for prosthetics of amputees has proven difficult.
However two new solutions have been reported for making an artificial skin that possesses an extremely sensitive sense touch. One comes out of the University of California Berkeley and the other comes ironically from neighbor and rival Stanford University, both of which were reported in the journal Nature Materials.
In keeping with the rivalry we get a good run down of the pros and cons of each technology in the BBC article cited above. The Stanford research, led by Zhenan Bao, produces the same pressure sensing as the Berkeley research but with fewer layers by making its nanowire-enabled thin-film transistors (TFTs) pressure sensitive rather than laying the nanowire TFT array onto a pressure-sensitive array.
Despite this advantage, the Berkeley solution has greater flexibility, leading Bao to concede in the article that her group’s approach will need to develop a better conductive rubber.
Both solutions have demonstrated remarkable sensitivity. The artificial skins react to a stimulus in a tenth of a second and in weights ranging five grams per centimeter to 40 times that amount, according to the BBC article. According to the video below, the Stanford development could sense the touch of a butterfly or a drop of water.
As impressive as this is, perhaps the greatest part for both these lines of research are that they were able to accomplish their results by using fairly inexpensive manufacturing techniques.
In a critique for Nature Materials John Boland, a nanotechnologist from Trinity College Dublin, commented, "Perhaps the most remarkable aspect of these studies is how they elegantly demonstrate that it is possible to exploit well-established processing technologies to engineer low-cost innovative solutions to important technical problems."