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Chapter 9
Implementing a Fuzzy Controller
Fuzzy Controller Implementation
Now incorporate the fuzzy controller into the application block diagram.
You do not need to program the fuzzy controller, just use the pre-defined
Fuzzy Controller VI available with the Fuzzy Logic Controls, shown in
Figure 9-10.
The pre-defined Fuzzy Controller VI can be connected with as many as four
input signals from a process and one output signal used as a control value.
Although the Fuzzy Controller VI has many different inputs and outputs, at
this time you only need those inputs and outputs shown in bold in
Figure 9-10.
Figure 9-10. Fuzzy Controller VI
You can connect the input signals TH/TS and (TU–TD)/TS to the Fuzzy
Controller VI inputs input1 and input2. You also can connect the output
signal of the Fuzzy Controller VI, called analog output, to the input side
of the NumtoString VI. Leave the rest of the inputs unconnected at this
time.
Loading Fuzzy Controller Data
You can compare the Fuzzy Controller VI to a microprocessor that does not
have an executable program loaded. To obtain the specific data for the
fuzzy controller, you must use the Load Fuzzy Controller VI to load the
required data into the Fuzzy Controller VI. This VI also is included in the
Fuzzy Logic Controls.
PID Control Toolset User Manual
9-8
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