Scientists create an electronic nose that will serve as a chemical sensor • Earth.com

Some animals have a remarkable sense of smell, a level of sensitivity that allows them to explore and understand the world around them. Scientists at Georgia Institute of Technology analyze the exceptional odorous capacity of animals to develop a chemical sensor that can be applied to critical tasks ranging from food security to national security.

Thomas Spencer is a Ph.D. candidate in David Hu's laboratory, an associate professor of mechanical engineering and biology at Georgia Tech.

"We turned to animals to understand what nature already understood," said Spencer. "We apply the underlying principles we learned about these mechanisms to design a better sensor."

The research was launched by a competition to develop a sensor capable of identifying different varieties of cheese. The team went to the Atlanta Zoo to compare how different animals sniff, from mice to elephants.

"We wanted to measure the frequency of inhalation of animals when they were trying to identify a new food source or something that interested them," explained Spencer.

The researchers found that an animal's sniffing speed decreased with increasing body size. For example, mice sniff faster than elephants. Based on these findings, the team designed a custom pump that oscillates at the same frequency as the animals.

"These results are important because they give us insight into the physics of sniffing," said Professor Hu. "This information will affect how we develop sniffing machines."

Wind tunnel experiments and computer simulations allowed the experts to analyze how the odorous particles moved in the air. In addition, they were able to collect sensor information in real time to observe variations of chemical compounds in the air in space and time.

Although the device was originally designed to distinguish different varieties of cheese, the fundamentals involved could be used in many important applications.

"It's still a relatively new study," said Spencer. "Our hope is to obtain an excerpt from this ability and to reproduce it for ourselves."

Spencer will present the group's latest electronic nose project at the show American Physical Society71st Annual Meeting of the Division of Fluid Dynamics in Atlanta, Georgia.

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By Chrissy Sexton, Earth.com Editor
Image credit: Thomas Spencer