In: Zhou, M.C.: Petri Nets in Flexible and Agile Automation, pages 337-368. Dordrecht, NL: Kluwer Academic Publishers, 1995.
Abstract: The objective of this chapter is to give an insight to the problems of specification and synthesis of supervisory controller for manufacturing systems. The current practice in industry ranges from the low level ladder logic programming of PLCs to the high level graphical models which could automatically be translated into an executable code. For example, the use of GRAFCET and Sequential Function Chart to program PLCs have grown substantially in recent years. A main problem with all the existing models is that they do not provide the control engineer any means, other than simulation, of analyzing the functional and performance behavior of the supervised system. Also, with growing interest in lean manufacturing, there seems to be an increasing need for some formal methodology which takes the system requirements specification as an input and gives the supervisory control as its output. The existence of such a formal and analytical methodology would minimize the need for debugging and verification of the supervisory control implementation and at the same time would substantially reduce the time and cost of its development. This concept exists in theory but has very limited applications. In this chapter, we plan to explore some of this theory.