The EXACT Pattern Recognition Adaptive Controller, a User-Oriented Commercial Success

  • E. H. Bristol

Abstract

A pattern recognition-based adaptive control concept (termed EXACT 1) has been commercialized successfully as a universal successor to The Foxboro Company’s current electronic controllers. The delay in market entry was a consequence of a design, incredible (for different reasons) to both academic and practitioner. Yet it evolved not as a regression from the now standard, theory motivated, model-based designs, but as an artificial intelligence related advance over them, suggested by studies on the effects of mismodeling. In this regard, it offers superior adaptation through direct performance feedback. In the absence of a general adaptation theory, an essential element contributing to the development of the EXACT concept was an experimental analysis technique which permitted rigorous demonstration of the general applicability of the method.

Its current success is also derived from a clear understanding of the fundamental role of the PID controller in process control, a role that has allowed the PID controller to prevail and outperform practically its many proposed competitors, each of which, by itself, exhibits apparently superior theoretical performance. The distinctive character makes the design an interesting case study subject of the interplay between market, technology, and innovation. The EXACT Controller has been recognized by three commercial awards.

Keywords

Adaptive Design Nonminimum Phase Adaptive Loop Adaptive Process Control Exact Controller 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Science+Business Media New York 1986

Authors and Affiliations

  • E. H. Bristol
    • 1
  1. 1.The Foxboro CompanyFoxboroUSA

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