Cats, rats, other mammals, and even some insects are well-known for using their hairlike tactile sensors -- whiskers -- to sense obstacles in their path and changes in the air. Now researchers at the University of California at Berkeley and Lawrence Berkeley National Laboratory have created "electronic whiskers" that could help robots navigate with similar sensitivity.
Their research, detailed in a paper titled "Highly sensitive electronic whiskers based on patterned carbon nanotube and silver nanoparticle composite films," appears in the Proceedings of the National Academy of Sciences and explains how these e-whiskers can be made and used to map airflow in real time.
The e-whiskers respond to the slightest changes in pressure -- in fact, "in tests, these whiskers were 10 times more sensitive to pressure than all previously reported capacitive or resistive pressure sensors," lead researcher Ali Javey said in a statement.
The nanotubes used are highly flexible and conductive, and very sensitive to strain, making the whiskers capable of sensing pressure as minimal as a single Pascal. A gentle breeze is about 10 Pa, according to Wikipedia, so these robots could feel the slightest breath -- or perhaps a gas leak?
"The active component is based on composites of carbon nanotubes and silver nanoparticles that are painted on high-aspect-ratio fibers," the study's abstract explained. "The resistivity of the composite films is highly sensitive to mechanical strain and can be readily tuned by changing the composition ratio of the components."
As a proof of concept, the researchers fabricated e-whiskers to demonstrate real-time gas-flow mapping with high accuracy in both two and three dimensions. "This work may enable a wide range of applications in advanced robotics and human-machine interfacing," the abstract concluded.
Human-machine interfacing? If they're making whiskers for robots, does that mean people are next? We can't wait to hear more.