This paper describes a robust PID autotuner embedded in a block library for constructing both simulated and real control systems. The library has been implemented in a visual programming tool and contains all the functions for building complete systems, similar to those provided by a typical CACSD (computer-aided control system design) environment. After a brief overview of the library, the paper concentrates on describing the PID autotuning tool, its implementation and operation. The underlying theoretical background is simply sketched out to permit the necessary degree of comprehension, and for its complete illustration the interested reader is referred to more specific works. Some examples of the autotuner’s operation, one of which refers to a laboratory plant, are also reported.
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