Cyborg insects as wireless biorobotic sensing machines

June 29, 2016 // By Jean-Pierre Joosting
A team of engineers from Washington University in St. Louis is developing biorobotic sensing systems based the sense of smell in locusts that could be used in security applications to sniff out explosives.

Associate professor of biomedical engineering in the School of Engineering and Applied Science, Baranidharan Raman has received a three-year, $750,000 grant from the Office of Naval Research (ONR) to use the highly sensitive locust olfactory system as the basis to develop a bio-hybrid nose.

Biological sensing systems are far more complex than their engineered counterparts, including the chemical sensing system responsible for our sense of smell, Raman said. Although the sense of smell is a primitive sense, it is conserved across many vertebrate and invertebrate species.

"It appears that biology converged onto a solution for the problem of non-invasive, or 'standoff' chemical sensing and has replicated the same design and computing principles everywhere," Raman said. "Therefore, understanding the fundamental olfactory processing principle is necessary to engineer solutions inspired by biology."

For several years and with prior funding from the ONR, Raman has been studying how sensory signals are received and processed in relatively simple brains of locusts. He and his team have found that odors prompt dynamic neural activity in the brain that allow the locust to correctly identify a particular odor, even with other odors present. In other research, his team also has found that locusts trained to recognize certain odors can do so even when the trained odor was presented in complex situations, such as overlapping with other scents or in different background conditions.

"Why reinvent the wheel? Why not take advantage of the biological solution?" Raman said. "That is the philosophy here. Even the state-of-the-art miniaturized chemical sensing devices have a handful of sensors. On the other hand, if you look at the insect antenna, where their chemical sensors are located, there are several hundreds of thousands of sensors and of a variety of types."