University of Washington researchers continue to push the boundaries between the technical and insect worlds in the pursuit of gaining greater understanding of and access to hard-to-reach places. The latest development involves the use of a live moth antenna attached to a drone dubbed the “Smellicopter.”
Th autonomous drone uses the antenna — wired directly to its electrical circuit — to navigate toward smells. The small Smellicopter also senses and avoids obstacles as it flies, thanks to the Manduca sexta hawkmoth’s body part.
The research is intended to showcase how devices can can be used in areas that require faster, more sensitive odor processing or where it might be too dangerous for humans, including structures damaged in a disaster where gas leaks or explosives may be present. Melanie Anderson, a UW doctoral student in mechanical engineering, is lead author on study results published Oct. 1 in the journal IOP Bioinspiration & Biomimetics.
“Nature really blows our human-made odor sensors out of the water,” Anderson told UW News. “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 antenna were removed from specimens that were anesthetized in a refrigerator. Once separated, the antenna stays biologically and chemically active for up to four hours. The cells in the antenna amplify chemical signals and trigger cellular responses in the moth. On the drone, tiny wires are added to the antenna, which connect it to an electrical circuit.
Smellicopter uses an antenna attached to an open-source hand-held commercially available quadcopter drone platform that allows users to add special features. Two plastic fins were added to the back of the drone to create drag to help it be constantly oriented upwind.
The UW team created a “cast and surge” protocol for the drone that mimics how moths search for smells, so Smellicopter searches for odors without direction from researchers. It begins its search by moving to the left for a specific distance. If nothing passes a specific smell threshold, Smellicopter then moves to the right for the same distance. Once it detects an odor, it changes its flying pattern to surge toward it, UW News reported.
In lab tests, Smellicopter naturally flew toward smells that moths find interesting, such as floral scents. Researchers hope the moth antenna could be used to sense other smells in the future, such as the exhaling of carbon dioxide from someone trapped under rubble or the chemical signature of an unexploded device.
