Qualitative identification of objects by means of Fuzzy Logic


Qualitative identification of objects by means of Fuzzy Logic
For a glass recycling system, for example, the objects must be sorted and melted down according to their color. The precision of the sensors used for identifying them is, however, not so precise to allow a clear-cut distinction, owing to factors like the tone and purity of the colors, environmental luminosity, and translucency of the object. Which, then, are the values of the three RGB components to use for mapping the color of the object with a basic color?
By using precise values,we can identify white with (255, 255, 255), but the triple (249, 249, 249) will not be recognized as white. will not be recognized as white,
Using fuzzy logic allows us to solve this type of problem, and other far more complex ones as well, by letting us give a linguistic description of the system based on fuzzy values and a series of rules.
To solve this simple problem, a fuzzy system has been definited with three antecedents (input), represented by the three RGB components, and one consequents (output), which represents the color identified. The fuzzy sets are defined with two triangular membership (Low e Hi) on a 256 base and a center, respectively, 0 e 255. The Universe of Discourse therefore ranges from 0 to 255. The output is an integer Crisp value between 0 and 7. The set of rules, eight in all, is very simple:

if Red is Low and Green is Low and Blue is Low then Color is Black
if Red is High and Green is Low and Blue is Low then Color is Red
if Red is Low and Green is High and Blue is Low then Color is Green
if Red is Low and Green is Low and Blue is High then Color is Blue
if Red is High and Green is High and Blue is Low then Color is Yellow
if Red is Low and Green is High and Blue is High then Color is Cyan
if Red is High and Green is Low and Blue is High then Color is Magenta
if Red is High and Green is High and Blue is High then Color is White

The application of these simple rules and the use of the defined fuzzy sets allows us to solve the problem with a certain degree of precision.

Here is a simple demostration of an identification system. identification system .