Based On Object Expanded Colored Petri Net And Applying In The Modeling Of FMS Logistic System

The Flexible Manufacturing System (FMS) is an automated machinery manufacturing system, which is made up of logistics system and information control system. As a manufacture mode of multi-type and medium/miniature batch, it can adapt the change of different process objects. In the past, People only carried on deeply research to the activity of processing in the manufacturing system. It is very difficult to make the obvious benefit from the activity of processing. However, the logistics activity in the ground floor of manufacturing industry can reduce the production cost, it is the one that can be studied and have fields in which greater potentiality can be excavated. Because in the whole course of production, only 5% time is used for processing the activity, 95% of the time is used for storing, loading and unload, waiting to process and send. So, whether logistics system could work high-efficiently and rationally, directly determines the production efficiency of the whole FMS and size of flexibility. In the logistics system, the supplies flow and corresponding information flow are highly unanimous, otherwise will present the phenomenon with confused logistics and information flow. If you want to guarantee the synchronism of supplies flowing and information flow, must carry on the modeling and emulation to FMS logistics system. It is the problems that a lot of specialists and scholars have paid attention to studying that the modeling and emulation about FMS logistics. This thesis has synthesized the current situation of domestic and international study on FMS logistics at present, has proposed Expanded Coloured Petri Net (ECPN) analytical method. ECPN model combine the advantage of Object-Oriented technology and Coloured Petri Net, shines FMS logistics system upon the system structure of the steps on the third floor. It is separately physics layer, abstract layer, Control / Policy-making level. The physics layer is the most low of the whole system, each entity of resources in the physics layer divide into pieces of objects cooperating each other. Abstract layer is shining upon to the physics floor, replacing the each entity of objects with the Expanded coloured Petri Net module. The information interchanges between the modules, expressing with information token. Finally, Utilizing Petri Net comprehensive technology amalgamate each coloured Petri Net module, and become a large-scale comprehensive Petri Net.Control / Policy-making level, controlling and coordinating each physics activity, is the most top of the system, work piece and circulation of message of objects through controlling the exciting of the gate. The whole system integrates every layer with the information position. ECPN model encapsulating object's attribution and operation into Class,is divided into father Net and sub Net. The father Net can transfer the Sub net, the parameter from father's network is passed to the sub Net. Meanwhile, ECPN model separates the synchronous restraint existing in FMS logistics out from objects, made the systematic model well arranged and the structure clear. Chapter Four in the thesis, utilizing the definition of deadlock that ECPN model given, proposes the corresponding control rule of deadlock. In short, ECPN has basically solved "sealing" and "state space explosion" problems in the Petri Net's application.