Decentralised supervisory control of discrete event systems with mutual observability

An extended decentralised supervisory control framework of discrete event systems is considered, in which a certain number of local supervisors are required to disable a controllable event. The mutual observability, which is an extended concept of the conventional co-observability, is presented to increase the system´s efficacy. Based on the mutual observability, the authors investigate the necessary and sufficient conditions for the existence of the extended decentralised supervisory control.