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Chapter 7
Using the Fuzzy Logic Controller Design VI
Figure 7-9. All Vehicle-Position Terms Named Correctly
The Fuzzy-Set-Editor offers many functions that you can use to modify
single terms or the whole term arrangement of the active variable. It is
a good idea to experiment with this function at this point in your project
because you must modify the whole term arrangement according to the
desired term arrangement shown in Figure 4-6, Linguistic Variable Vehicle
Position x and Its Linguistic Terms. Figure 7-10 shows the term
arrangement you obtain when you select edit»full term-overlap all, which
results in a term arrangement with all terms of the active linguistic variable
completely overlapping each other.
The edit menu also has several other functions for automatically editing
membership functions. You can change individual membership functions,
or all of the membership functions, to singleton fuzzy sets, which are
typically used only for controller output. The tolerance function changes
a trapezoidal membership to a triangular function. In addition, you can set
the overlap between functions and make all functions symmetric. This
command does not affect the left side of the left-most term and the right
side of the right-most term.
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PID Control Toolkit User Manual