Credit: Ali Javey and Kuniharu Takei;

Every day we use our sense of touch to guide our way through life without giving it a second thought. Engineers have long sought to replicate the complex sense of touch in electronic components to give robots and, eventually, prosthetic limbs the same ability to interact with the surrounding world. A group of electrical engineers at UC Berkeley have made a significant breakthrough in the pursuit of producing a sensor similar to human skin in its ability to detect pressure. Professor Ali Javey and his team fabricated a seven square centimeter sensor array using inorganic semiconductors called nanowires mounted onto flexible, pressure-sensitive rubber. Previous electronic kins used flexible organic components that were 50 times smaller in area and required a large battery to provide the voltage needed to operate them. Javey’s group instead opted to use nanowires that require smaller voltages. "Previous research using nanowires was limited to using single nanowire transistors on a very small scale,” says Dr. Kuniharu Takei, a postdoctoral scholar in Javey’s group and lead author of the paper. The sensor makes use of an innovative contact printing technique pioneered by the team to mount hundreds of nanowires onto the sensor. The electronic skin is durable, making it ideal for future applications, which Javey explains can range, “from robotics, to giving gas pipelines the ability to self diagnose the formation of cracks, and one day even interfac- ing with prosthetic limbs.”