Smell is the sense that most we are having trouble developing electronically, but we are achieving it thanks to a very ingenious technology.
Our sense of smell is capable of detect, analyze and provide us with an emotional reaction formerly tiny particles of almost any substance found suspended in the air. The mesh of olfactory receptors and nerve connections that coat and send this information to the brain has not yet been electronically replicated, and one would think that it is a much simpler sense than, for example, that of sight. But nowe don’t have a decent electronic nose yet.
To understand why we still don’t have an electronic nose and how will these work when they come in the futureWe must first understand what odor is and what it means to smell from a scientific and rigorous point of view. To do this, of course, we will first look at the characteristics of a nose and how we can electronically replicate those characteristics that are important to to be able to smell and thus create an electronic nose.
What does it mean to smell, explained simply
In a simple way, smelling means recognize the different chemical compounds that are suspended in the air. Our nose is not sensitive to all compounds but only to some, which are what we detect as odorous compounds, for example the one to drop a garbage bag full of fish after two days in the sun, we are very sensitive to these types of compounds.
The problem is that it is very difficult to detect these particles in suspension and measures are always destructive. In fact, one of the biggest problems that exist is that suspended particle detectors, which is the closest thing we have in mass production to an electronic nose, is that they are very specific and are not capable of detecting the variety of particles that can detect our olfactory systems. Well, and what is more, this electronic nose is take up a lot of space and take a long time in carrying out analyzes.
MEMS, the secret of the electronic nose of the future
However, thanks to MEMS (Microelectronic Mechanical Systems) all these problems can be solved. These devices are small electronic devices that are capable of producing micro-movements which can then be used to analyze even nanoscopic samples. In the case of the electronic nose, we would be talking about a small metal arm impregnated with a sticky substance that when it catches a molecule in suspension vibrates. These vibrations are tiny and it takes a very ingenious system to measure and analyze them.
To measure these vibrations, a laser is passed that is reflected several times in this metallic layer. Depending on the position and speed of the sheet, the light at the end of the path has some properties or others and this can be measured and analyzed to get the type of particle that got stuck in the sensor of our electronic nose.
From here the possibilities are limitless. From being able to detect with a small electronic device when food is decomposing to instantly diagnose diseases just by breathing on a meter, by returning the sense of smell to anyone who has lost it. An electronic nose can be a breakthrough for the life we live and make our day to day much better and more comfortable.