One huge advantage of drones is that these little robots can go places where people can't, including areas that might be too dangerous, such as unstable structures after a natural disaster or a region with unexploded devices.
Researchers are interested in developing devices that can navigate these situations by sniffing out chemicals in the air to locate disaster survivors, gas leaks, explosives and more. But most sensors created by people are not sensitive or fast enough to be able to find and process specific smells while flying through the patchy odor plumes these sources create.
Now a team led by the University of Washington has developed Smellicopter: an autonomous drone that uses a live antenna from a moth to navigate toward smells. Smellicopter can also sense and avoid obstacles as it travels through the air. The team published these results Oct. 1 in the journal IOP Bioinspiration & Biomimetics.
"Nature really blows our human-made odor sensors out of the water," said lead author Melanie Anderson, a UW doctoral student in mechanical engineering. "By using an actual moth antenna with Smellicopter, we're able to get the best of both worlds: the sensitivity of a biological organism on a robotic platform where we can control its motion."
The moth uses its antennae to sense chemicals in its environment and navigate toward sources of food or potential mates.
"Cells in a moth antenna amplify chemical signals," said co-author Thomas Daniel, a UW professor of biology who co-supervises Anderson’s doctoral research. "The moths do it really efficiently — one scent molecule can trigger lots of cellular responses, and that's the trick. This process is super efficient, specific and fast."
The team used antennae from the Manduca sexta hawkmoth for Smellicopter. Researchers placed moths in the fridge to anesthetize them before removing an antenna. Once separated from the live moth, the antenna stays biologically and chemically active for up to four hours. That time span could be extended, the researchers said, by storing antennae in the fridge.
By adding tiny wires into either end of the antenna, the researchers were able to connect it to an electrical circuit and measure the average signal from all of the cells in the antenna. The team then compared it to a typical human-made sensor by placing both at one end of a wind tunnel and wafting smells that both sensors would respond to: a floral scent and ethanol, a type of alcohol. The antenna reacted more quickly and took less time to recover between puffs.
Read the full article in UW News.
Bonus: read related article in The Burn-In.