Metapetrinets for Controlling Complex and Dynamic Processes

Multilevel petrinets are proposed for facilitating exible modeling and control of complicated dynamic processes, especially autonomous, learning and intelligent systems. A metapetrinet is able not only to change the marking of a petrinet but also to recon gue dynamically its structure. Each level of the metanet is an ordinary petrinet of some traditional type. A basic level petrinet simulates the process of some application. The second level, i.e. the metapetrinet, is used to simulate and help controlling the con guration change at the basic level. There is a conformity between the places of the second level structure and places or transitions of the basic level structure. The main control rule is such that a certain place or transition is removed from the present con guration of the basic level if the corresponding place at the metalevel becomes empty. If at least one token appears to an empty metalevel place, then the originally de ned corresponding basic level place or transition immediately is created back to the con guration. We also introduce multilevel metapetrinets where every upper level may change the con guration of the previous lower level. In such a case even a few levels with a simple structure are able to simulate quite complicated control processes at the basic level. We claim that metapetrinets o er more compact facilities to the models of complex dynamic processes than single level petrinets.