Researchers follow their electronic nose
Apr 14, 2004
by Ryan Smith
Two researchers at the University of Alberta have been working to make this scenario a reality. Their latest success, the development of an electronic nose for multimedia use, was reported recently in IEEE Transactions on Consumer Electronics.
Dr. Mrinal Mandal, a professor in the U of A Department of Electrical and Computer Engineering, and Rafael Castro, a master's student studying under Mandal, have developed an apparatus that will recognize the odours of 10 different smell groupings, including fruit, coffee, gases, spices and just about everything in between. The device would connect to a personal computer, which then determines what smell the electronic nose has captured.
Smell detectors are currently used in various industries to detect cyanide gases and rotten fish--jobs that would make people sick or would be unpleasant, Mandal said. But these 'noses' are expensive and wouldn't be appropriate for multimedia use because they have been designed only to complete specific, narrowly defined tasks, he added.
Castro built his electronic nose entirely with inexpensive electronic parts that can be found in any hardware store.
"The nose works in a more complex way than the eyes do," said Mandal, explaining the challenges in building the system. "There are primarily three colour receptors in the human eye, but there are several million smell receptors in the nose and about 1,000 different types of receptors, so you need to create at least 1,000 smell channels to build a good electronic nose."
Mandal and Castro also ran into a few difficulties they didn't expect. For one, smells--unlike visual images or audio signals--require the movement of molecules, which means that smells can be sticky and can linger. To solve this problem, Castro devised a pump "cleaning system".
According to Mandal and Castro, the next step in order to add smell to the multimedia experience is to develop a low-cost generation system--a challenge Castro believes will be easier than it was to develop the system that captures the smell. A palate of molecules would be kept in a smell-generating apparatus attached to the computer and then mixed and matched to form a desired odour, Castro explained.
Mandal, who has recently written a book on multimedia, envisions that a mass-produced, inexpensive electronic nose may become available sometime in the next five to 10 years, though both men say their interest in the research is more academic than commercial.
"It is a big challenge. And I love challenges," Castro said.
Related links – internal
The U of A Department of Electrical and Computer Engineering website: http://www.ece.ualberta.ca/
Dr. Mrinal Mandal's U of A webpage: http://www.ece.ualberta.ca/~mandal/
Related link – external
The IEEE website:
This article originally appeared in the University of Alberta's ExpressNews