An electronic nose (e-nose) is an electronic device composed of one or more odor sensors, a microcontroller, electronic components, and software that acquire and analyze a gas or volatile organic compound (VOC) present in an environment. E-noses attempt to identify the gas or VOC based on their chemical composition, sending electronic data about the detected odor signature to a computer, akin to an animal nose identifying odors and sending electro-chemical signals to an animal brain. Then the computer will attempt to identify the perceived odor. E-noses have been used in human-computer interaction in specialized computing applications containing a user interface (UI) with a purpose, supporting its user to identify an odor and its properties, and communicating information about the odor on the UI.
E-nose information can be communicated to the user in different information presentation modalities using practically all the human sensory channels. In the context of HCI, a modality is considered as a single independent input/output sensory channel between a human and a computer. Odor fingerprint results generated by the e-nose can be presented visually, and aurally, playing sound through a buzzer. Other sensory modalities could be used, such as representing odor information through haptics that can be perceived with the sense of touch.
Recent advances in the development of e-noses have been extensive, as the literature of recent years can testify. This work describes some of the current e-noses development projects impacting people through HCI.