Electronic Noses. Principles and Applications

Abstract

Listen

Translate article

The measurement and estimation of human-related senses hasbecome an established technique in sensor research, as well as inthe practical design of measurement and control systems. Theelectronic nose concept is widely used as an analytical tool inindustry today. The commercialization of the electronic nosebegan in 1993 as the concept became widelyaccepted as an effective instrument for detection and estimationof olfaction. The book describes the general set-up of anelectronic nose: it consists of an array of chemical sensors; anair flow system, which switches the reference air and the testedair; a signal analysis technique; and a presentation unit. Themain sensor principles presented in the book are also the mostfrequently used techniques for gas sensors. These are based ontwo main types of gas sensor: metal-oxide semiconductors andconducting polymer resistive materials. An overview of other gassensor principles is also given, for example, gas sensorsbased on the effect of sorbed molecules on the propagation ofacoustic waves; field effect semiconductors; electrochemicaloxidation and reduction principles; and a catalytic gas sensor. Pellistors are described as well as fibre-optic gas sensors. Toincrease the complexity of the odour system, an array of mixedsensing principles is often designed, consisting of different types of sensor, in order to create differences in operatingtemperatures, flow conditions and sensor response times. Theanalysis technique used, in most cases, is a supervisedartificial neural network used in a relative based measurementapproach, although other techniques are also mentioned in the book.The book describes a survey of both chemical properties ofodorous molecules as well as biological olfaction from theperspective of human perception. However, many animals havemore sophisticated systems, and it would have beeninteresting to make comparisons.The applications and three case studies show the direction ofthe research and development over the last decade. However, thepresentation of most of the results as principal component plotsindicates that major work is needed to achieve a more human-friendly interface. The next decade should see the developmentof electronic nose systems into a variety of applications toincrease the quality of life as well as for monitoring environmentalinformation. This means that artificial human-related sensorsystems could become everyday tools for estimation of your ownpersonal condition as well as that of the environment.In general, the book presents thestate-of-the-art in electronic noses. It can also be consideredas an introduction to the subject of electronic noses. This opinionis supported by a sufficiently complete set of references and agood introduction to the chemical, biological and physicalbackground of electronic noses. The book is characterized by a methodical and thorough treatment of the subject matter. Thechapters are logically related, and each has its ownintroduction and bibliography. This approach makes it easy forany reader with only a basic knowledge of related subjects.However, for researchers, the material and examples feel a littleold, since the last three or four years have seen an enormousamount of activity in the field of human-related artificial sensor systems, where the electronic nose is often integratedinto more complex systems. By fusing sensor data into a hybridsensor, or by more complex signal analysis combining data fromother sensor modalities such as electronic tongues, we aim tomake inferences that may be impossible from a singleartificial sensor. Furthermore, a whole electronic head integrates information from all five human-relatedartificial senses.However, it remains true that, in a particular area stronglyrelevant to human-related quality estimation, this book is avaluable and accessible guide and reference. I strongly recommend it as ahandbook for users of commercial electronic nose instruments and, particularly for its references to related works. Peter Wide