Structured synthesis of fault-tolerant supervisory controllers

Supervisory control synthesis for discrete-event systems can help in overcoming the growing complexity in the process of designing supervisors for cyber-physical systems. This is especially the case when fault-tolerance needs to be taken into account. The aim of this paper is to present a structured way of working that can be used for this purpose. Special attention is given to partitioning plant models and requirement models according to nominal and post-fault behavior. Extended finite-state automata and state-based requirement models are used as the modeling formalism. A case study involving a movable bridge (state space size: 8.4 × 1025) is presented to illustrate the proposed method.