In: Integration of Software Specification Techniques for Applications in Engineering: Priority Program SoftSpez of the German Research Foundation (DFG), Final Report, pages 270-300. Volume 3147 of Lecture Notes in Computer Science --- Springer-Verlag, September 2004.
Abstract: In this paper we summarize syntax and semantics of modules of elementary signal nets and explain how to synthesize the control for discrete event systems modelled by such modules. Signal nets are based on Petri net modules which communicate via signals. Two kinds of signals are employed, namely active signals which force occurrence of (enabled) events, and passive signals which enable/prohibit occurring of events. Modelling with such modules appears to be very natural from an engineering perspective. It enables hierarchical structuring and supports the locality principle. Given an uncontrolled system (a plant), modelled by a module of an elementary signal net, and a control specification, given as a regular language representing the desired signal output behavior of this system, we show step-by-step how to automatically synthesize the maximally permissive and nonblocking behavior of the plant respecting the control specification. Finally, we show how to synthesize the controller (as a module of an elementary signal net) forcing the plant to realize the controlled behavior.