Research On CPS Modeling Method Based On Augmented Hybrid Petri Nets

CPS is a kind of complex hybrid system which integrates the information discrete system and the physical continuous system.It involves many kinds of technologies such as perception,communication,calculation and control,and finally realizes the interconnection,mutual inductance and mutual control among people and things.Because CPS is relatively large,including a large number of distributed,heterogeneous,concurrent and real-time components,which brings great challenges to CPS modeling.Aiming at the problem of CPS modeling,this dissertation has done the following work:(1)This dissertation summarizes the characteristics and modeling challenges of CPS,concludes the mainstream methods and tools of CPS modeling,selects the formal methods and Petri nets as the modeling methods and tools of this dissertation,and proposes a new CPS architecture based on the event driven properties of Petri nets,and gives the operation mode of CPS,the formal definition of physical entities and the formal definition of CPS events that can describe the temporal and spatial changes of entities;(2)Although hybrid Petri nets improve the modeling and description ability of prototype Petri nets for continuous systems,there are also many modeling problems and errors in the face of complex systems such as CPS.In view of this situation,this dissertation proposes an augmented hybrid Petri net model.By introducing the time and space attributes,as well as the concept of conditional arc,the modeling and description ability of the hybrid Petri net model is extended,and the work flow of ACC system and LKA system in the vehicle driverless system is modeled,and the corresponding model diagram is constructed;(3)Using the idea of aspect oriented programming,the concept of aspect net is introduced.Aspect net is used to describe the non-functional attributes of CPS.The weaving rules of aspect net and augmented hybrid Petri net,and the combination rules of multiple aspect nets are given.Finally,the aspect net and augmented hybrid Petri net are combined into a complete net system by weaving technology to realize the complete modeling of CPS;(4)The augmented hybrid Petri net model is transformed into a time automata model which can be processed by UPPAAL.The model checking tool UPPAAL is used to analyze and verify the model.The augmented hybrid Petri nets and the weaving technology of aspect nets proposed in this dissertation can effectively reduce the complexity of CPS model and improve the integrity of the model.