English

Coordination Control of Discrete-Event Systems Revisited

Optimization and Control 2017-11-15 v1 Formal Languages and Automata Theory

Abstract

In this paper, we revise and further investigate the coordination control approach proposed for supervisory control of distributed discrete-event systems with synchronous communication based on the Ramadge-Wonham automata framework. The notions of conditional decomposability, conditional controllability, and conditional closedness ensuring the existence of a solution are carefully revised and simplified. The paper is generalized to non-prefix-closed languages, that is, supremal conditionally controllable sublanguages of not necessary prefix-closed languages are discussed. Non-prefix-closed languages introduce the blocking issue into coordination control, hence a procedure to compute a coordinator for nonblockingness is included. The optimization problem concerning the size of a coordinator is under investigation. We prove that to find the minimal extension of the coordinator event set for which a given specification language is conditionally decomposable is NP-hard. In other words, unless P=NP, it is not possible to find a polynomial algorithm to compute the minimal coordinator with respect to the number of events.

Keywords

Cite

@article{arxiv.1307.4332,
  title  = {Coordination Control of Discrete-Event Systems Revisited},
  author = {Jan Komenda and Tomas Masopust and Jan H. van Schuppen},
  journal= {arXiv preprint arXiv:1307.4332},
  year   = {2017}
}