Artificial Nose

In this project, undergraduates are working together with graduate students and faculty to develop an artificial "nose" that can detect and classify odors. Since odorant compounds are detected in the gas phase, it is necessary to use gas sensors that can distinguish between different compounds. In this project we are using commercially available sensors which contain specially prepared tin-oxide elements. These sensor elements are heated by an applied voltage during normal operation. No one sensor can usefully distinguish among the thousands of odors of possible interest, but by using an array of various kinds of sensors operating at different heater voltages, it is possible to associate a given odor with a specific response pattern.

Looking "up the nose." Three tin-oxide sensors are visible inside the plexiglass sampling chamber.

Kevin Dunman uses the electronic nose to sample odors of household chemicals.

Interface board connects heater current, reference voltage, and signal lines to the electronic nose.