TEL-AVIV, Israel — Airports and train stations all over the world may soon switch out drug-sniffing dogs for their not nearly as cuddly robotic counterparts. A technological breakthrough by a team at Tel Aviv University has made it possible, for the first time ever, for a robot to smell odors using a biological sensor. The sensor works by sending electrical signals as a response to the presence of a nearby odor, which the robot can then go on to detect and interpret.
Initially, researchers successfully connected the biological sensor to an electronic system. Next, using a machine learning algorithm, the team was able to correctly identify odors with a level of sensitivity 10,000 times higher than that of a commonly used electronic device. Study authors believe that in light of these successful trials, this technology could help identify explosives, drugs, diseases, and more in the future.
This astounding technological breakthrough was led by doctoral student Neta Shvil of Tel Aviv University’s Sagol School of Neuroscience, Dr. Ben Maoz of the Fleischman Faculty of Engineering and the Sagol School of Neuroscience, and Prof. Yossi Yovel and Prof. Amir Ayali of the School of Zoology and the Sagol School of Neuroscience.
“Man-made technologies still can’t compete with millions of years of evolution. One area in which we particularly lag behind the animal world is that of smell perception. An example of this can be found at the airport where we go through a magnetometer that costs millions of dollars and can detect if we are carrying any metal devices. But when they want to check if a passenger is smuggling drugs, they bring in a dog to sniff him. In the animal world, insects excel at receiving and processing sensory signals. A mosquito, for example, can detect a 0.01 percent difference in the level of carbon dioxide in the air. Today, we are far from producing sensors whose capabilities come close to those of insects,” Dr. Maoz and Prof. Ayali explain in a university release.
Study authors explain that our sensory organs (eyes, ears, nose) – as well as those of all other animals – use receptors to identify and distinguish between different signals. From there, the relevant sensory organ translates those findings into electrical signals, which the brain then decodes as information.
The big challenge when it comes to biosensors is the connection of a sensory organ, like the nose, to an electronic system that will actually know how to decode the electrical signals received from the receptors.
“We connected the biological sensor and let it smell different odors while we measured the electrical activity that each odor induced. The system allowed us to detect each odor at the level of the insect’s primary sensory organ. Then, in the second step, we used machine learning to create a ‘library’ of smells,” Prof. Yovel comments. “In the study, we were able to characterize 8 odors, such as geranium, lemon and marzipan, in a way that allowed us to know when the smell of lemon or marzipan was presented. In fact, after the experiment was over, we continued to identify additional different and unusual smells, such as various types of Scotch whiskey. A comparison with standard measuring devices showed that the sensitivity of the insect’s nose in our system is about 10,000 times higher than the devices that are in use today.”
“Nature is much more advanced than we are, so we should use it. The principle we have demonstrated can be used and applied to other senses, such as sight and touch. For example, some animals have amazing abilities to detect explosives or drugs; the creation of a robot with a biological nose could help us preserve human life and identify criminals in a way that is not possible today. Some animals know how to detect diseases. Others can sense earthquakes. The sky is the limit,” Dr. Maoz concludes.
Moving forward, researchers aim to give the robot a navigation ability that will allow it to localize the odor source and eventually, its identity.
The study is published in Biosensor and Bioelectronics.