Since I was using a function generator whose Over,” “Mid Over,” “Over,” and “Far Over.” Now, I had to decide the range of these variables. Sets “Far Under,” “Under,” “Mid Under,” “Slightly Under,” “Close,” “Slightly You can define a maximum of 9 sets for each This controller would essentially onlyĬonsider the Error term in calculating its output, though considering multiple Named it “Error” and made it the first Fuzzy Controller input variable. I then took the difference of the two and The output of the Fuzzy Controller I named “Fuzzy Position”Īnd plotted versus “Wave Position,” the analog input. The voltage off of a function generator that was generating either sine, square We name and define our variables by going toįor example, the first Fuzzy Logic Controller I designed wasĪ simple controller to trace the data I collected of an analog channel on the LabView style, the Fuzzy Logic Toolkit is a GUI, a Graphical User Now, we go to the LabView Fuzzy Logic Toolkit which is Often referred to by “linguistic terms,” a way in which to describe the meaningĪnd Actual Position are two easily defined linguistic terms for use as input II: Designing a Simple Fuzzy Logic Controllerįirst, one must determine the input variables and the Logic necessary to writing a LabView Fuzzy Logic Controller. This should suffice to introduce the ideas behind Fuzzy The set “Over Target”, partially in the set “Close to target”, and partially in An error value of +8mm can exist partially in For instance, say we have created a feedbackĬontroller that is based on the error of control. )įuzzy Logic thus allows a degree of set membership. In the following picture, x is wholly in the sets A, B, and C in the traditionalĬan say x is in A to a degree of 0.7, 0.4 in B and 0.5 in C. Of a set or it isn’t, essentially a Boolean 1/0 classification. In traditional set theory, a variable is either an element Way they are helpful for problems that can not easily be set up mathematically, Fuzzy Logic Controllers are intended to “think” like humans do, in this

Logic was first developed in the state we know of now by Lofti Zadeh in the 1960’s. An Introduction to Fuzzy Logic Controllers in theįuzzy Logic is a variation on set theory where a variableĬan partially be an element of a set.

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