Supervision and Control of Heterarchical Discrete Event Systems

This paper presents a method for distributing centralized control models of discrete events systems (DES). The contribution of our approach is to offer a systematic way to decompose centralised models in order to obtain a modular representation of the production process. We observe as an advantage of this method that the main model properties are preserved and that the knowledge acquired during the modelling process is still valuable for the new structure. We emphasise that redundant information can be introduced to the system to increase local autonomy and to help the local fault detection and identification functions. Another important aspect is that the distributed models (sub-models) can be modified in order to increase their flexibility and to reach a more realistic behaviour representation. A set of terminologies and definitions related to the Control and Supervision domain are introduced in this paper to assist the understanding of our work.