The goal of much of the research regarding the olfactory system is to understand how individual odors are identified. Many researchers have produced mathematical models of the olfactory system. These models often include simulations of the neurobiological information processing systems.
It is interesting to consider that the mammalian epithelium contains from approximately 1 million sensory neurons in the mouse, to 10 million sensory neurons in the human, to 100 million sensory neurons in the pig.
Electronic noses are much simpler than almost all biological olfactory systems and detect only a small range of odors. However, for many potential tele-smell applications in the near future, a predetermined and limited set of odors is likely. Thus, it is likely an electronic nose will be a key component in an olfactory input to a telepresent virtual reality system.
Electronic/artificial noses are being developed as systems for the automated detection and classification of odors, vapors, and gases. The two main components of an electronic nose are the sensing system and the automated pattern recognition system. The sensing system can be an array of several different sensing elements (e.g., chemical sensors), where each element measures a different property of the sensed odor, or it can be a single sensing device (e.g., spectrometer) that produces an array of measurements for each odor, or it can be a combination. Each odor presented to the sensor array produces a signature or pattern characteristic of the odor. By presenting many different odors to the sensor array, a database of signatures is built up.