Some issues concerning decentralized supervisory control with communication

We continue to address the decentralized supervisory control problem with the added feature of communication between controllers. A general model is reviewed for dealing with this class of problems. Existence results for communication policies are revisited, and new results are given. Clarification is given for one-direction communication results that have appeared in the literature, and general one-way and two-way communication channel results are presented here for controllers with memory of prior communications. In addition, two fundamental difficulties associated with synthesis of optimal communication policies are discussed, and this discussion motivates the investigation of communication-policy synthesis for controllers that do not utilize knowledge of the communication policy to affect their estimates. In this case, a separation principle is utilized to allow synthesis with “simple” techniques