Automatic Reconfiguration of Untimed Discrete-Event Systems

TL;DR

This paper presents a supervisory control-based approach for reconfiguring untimed discrete-event systems, modeling reconfiguration requirements with a new specification and ensuring guaranteed reachability of desired configurations.

Contribution

It introduces the concept of reconfiguration specification and employs SCT synthesis to solve the reconfiguration problem through guaranteed reachability analysis.

Findings

Reconfiguration supervisor (RSUP) can be synthesized using standard SCT.

Guaranteed reachability of target configurations is achievable via backtracking.

The approach provides a formal framework for reconfiguration in DES.

Abstract

This work introduces a general formulation of the reconfiguration problem for untimed discrete-event systems (DES), which can be treated directly by supervisory control theory (SCT). To model the reconfiguration requirements we introduce the concept of reconfiguration specification (RS); here reconfiguration events (RE) are introduced to force a transition from one system configuration to another. Standard SCT synthesis is employed to obtain a reconfiguration supervisor (RSUP) in which designated states serve as the source states for RE. The reconfiguration problem itself is formulated as that of establishing guaranteed finite reachability of a desired RE source state in RSUP from the current state in RSUP at which a change in configuration is commanded by an external user. The solvability (or otherwise) of this reachability problem is established by backtracking as in standard dynamic programming.