Scientists create electronic nose to be used as a chemical sensor

There are some animals that have a remarkable sense of smell, with a level of sensitivity that allows them to explore and understand the world around them. Scientists at the Georgia Institute of Technology are analyzing the exceptional smelling ability of animals to develop a chemical sensor that could be applied to critical tasks ranging from food safety to national security.

Thomas Spencer is a doctoral candidate in the lab of David Hu, an associate professor of Mechanical Engineering and Biology at Georgia Tech.

“We turned to animals to understand what nature has already figured out,” said Spencer. “We are applying the underlying principles that we learned about these mechanisms to design a better sensor.”

The research was initiated by a competition to develop a sensor that could identify different varieties of cheese. The team had traveled to the Atlanta Zoo to compare the ways that different animals sniff, from mice to elephants.

“We wanted to measure the sniffing frequency of animals when they are trying to identify a new source of food or something that interests them,” explained Spencer.

The researchers found that an animal’s sniffing speed decreases as its body size increases. For example, mice sniff faster than elephants. Based on these findings, the team designed a customized pump that oscillates back and forth at the same frequency that animals sniff.

“These findings are important because it gives us insight into the physics of sniffing,” said Professor Hu. “This information will affect how we scale up sniffing machines.”

Wind tunnel experiments and computer simulations gave the experts an opportunity to analyze how the odor particles moved through the air. In addition, they were able to collect sensor information in real time to observe how the chemical compounds vary throughout the air in space and time.

While the device was initially designed to distinguish between different varieties of cheese, the fundamental principles involved could be used for many important applications.

“This is still a fairly new study,” said Spencer. “Our hope is to get a snippet of that ability and replicate it for ourselves.”

Spencer will present the group’s latest design for an electronic nose at the American Physical Society‘s Division of Fluid Dynamics 71st Annual Meeting in Atlanta, Georgia.

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By Chrissy Sexton, Earth.com Staff Writer
Image Credit: Thomas Spencer