Reserach On The Formal Modeling And Performance Evaluation Of Cyber Physical System Based On Modelica-AADL

Cyber physical system(CPS)is the product of the further development of the Internet of things.CPS combines the physical process with the computing process closely which belongs to a kind of complex hybrid system.Modelica and AADL are two embedded system architecture modeling languages which are suitable for CPS.Based on the modeling pattern of Modelica-AADL,this paper constructs the formal performance evaluation language and relevant algorithms to complete the specification of the system performance requirements.Furthermore,the related performance of CPS can be analyzed and evaluated.Firstly,this study applies Modelica and AADL,two unrelated modeling languages,to model CPS and combines them as a Modelica-AADL modeling pattern.Modelica is used for modeling physical systems.AADL is used for modeling information systems.The related probability expansion of Modelica is carried out,and the interface is designed to combine the two modes of modeling.At the same time,Z language is introduced into the Modelica-AADL model to describe the relevant data constraints in the system.In order to fulfill the relevant system analysis and evaluation work,the relevant rules and algorithms have been formulated to convert the non-formal Modelica-AADL description into a formal probabilistic hybrid automaton model.Then,through the definition of the formal performance evaluation language CTEL with calculation characteristics derived from some relevant statistical significance,this paper obtains the value of performance evaluation and gets the results of the analysis by evaluation logic CTEL describing the performance of one system.In the end,the performance evaluation is extended.Some statistical model checking methods are utilized to incorporate the probability measure into the category of performance evaluation.The statistical model checking framework under the probabilistic hybrid automaton is designed,and the evaluation analysis is extended to furnish a way to calculate the evaluation amount at a certain confidence level.In this paper,all parts of the modeling and analysis evaluation are explained with some examples,including the establishment of the Modelica-AADL model for the automobile engine system.On a practical perspective,the dynamic evaluation of engine system and the engine system energy evaluation under the confidence level are both calculated.