Research On The Modeling Method Of Spatiotemporal State Transition Events Of CPS Physical Entities Based On Spatiotemporal Petri Nets

The CPS(cyber-physical system,CPS)system is a real-time feedback system that combines continuous physical systems and discrete computing systems on the basis of traditional embedded systems.The system includes computing,communication,and control functions.It also embeds sensing,communication,and calculations into physical devices.The physical world and computing systems are unified and connected.Information fusion and behavioral interactions between the physical world and computing processes are emphasized.It is based on the embedded system and can guarantee the correctness and function optimization of the system execution.At the same time,the CPS system also pays attention to the consistency of information interaction and behavior between its internal information systems and physical systems.The CPS system can be said to have introduced physical and information systems on the basis of past embedded systems,and they have also been combined together with specific spatial attributes,but to a certain extent it has increased the difficulty and requirements of system modeling.This dissertation focuses on the general problem of spatio-temporal consistency of state transition of physical entities.It transfers the spatio-temporal architecture of the physical state;the accuracy and real-time performance of the change of the physical state of the physical state transition of the actuators;and the priority scheduling of physical entity state transfer actuators.These three small questions put forward their own research plans for the research points.(1)The primary task is to analyze the structure and characteristics of CPS physical entities and to classify them and formally define them.In addition to comparing the advantages and disadvantages of existing modeling methods,Petri nets are selected as their modeling tools,which are the basis of traditional Petri nets.On the introduction of time and space factors,a spatio-temporal Petri net TKPN model was constructed.(2)Then,the real-time spatio-temporal event model of CPS physical entity is constructed and modeled in the form of events.Then the CPS application example of train control system is selected to analyze the system structure of train control,and the train control system is divided into train entry model.The model of train outbound and the model of train entering and exiting station were modeled,and the model diagram of each situation was constructed.The feasibility of the model was analyzed through three aspects: the boundedness of Petri net,partial conservation and the activity of Petri net.Correctness.(3)Finally,the model was verified by UPPAAL model validation tool.