Automatic synthesis using genetic programming of an improved general-purpose controller for industrially representative plants

Most real-world controllers are composed of proportional, integrative, and derivative signal processing blocks. The so-called PID controller was invented and patented by Callender and Stevenson in 1939. In 1942, Ziegler and Nichols developed mathematical rules for automatically selecting the parameter values for PID controllers. In their influential 1995 book, Astrom and Hagglund developed a world-beating PID controller that outperforms the 1942 Ziegler-Nichols rules on an industrially representative set of plants. In this paper, we approached the problem of automatic synthesis of a controller using genetic programming without requiring in advance that the topology of the plant be the conventional PID topology. We present a genetically evolved controller that outperforms the automatic tuning rules developed by Astrom and Hagglund in 1995 for the industrially representative set of plants specified by Astrom and Hagglund.