Research On Model Transformation And Safety Analysis Method Based On SysML

In the past decade,with the deepening and functional enhancement of computer-based system applications,a number of safety critical areas such as aviation,medical care,and transportation have become larger and larger,and the system design and analysis problems involved have become more and more complicated.How to deeply study the modeling and safety analysis of complex systems has become a key topic of common concern in academia and industry.SysML is a general-purpose graphical modeling language widely used in aerospace industry at home and abroad.It is mainly used to design functions and performances of complex systems.However,SysML does not explicitly provide symbols and semantics for system function failures and event failures.Therefore,how to analyze and verify the safety of the system model with SysML as a typical is a very important issue.As a model-based safety analysis modeling language,AltaRica is mainly used to describe and analyze the architecture and failure behavior information of complex multi-level systems.It is widely used in the aviation industry and thus establishes a bridge between the SysML architecture design model and the safety analysis model can effectively ensure the synchronization of safety analysis and system design,which is beneficial to improve the efficiency of system safety analysis.The work of this paper is mainly around the Model Based Safety Analysis method,the specific work includes the following aspects:(1)A SysML safety analysis and verification framework based on model transformation is designed.Based on the characteristics of SysML and AltaRica and the challenges of complex system design modeling safety,the framework provides a logical diagram and data processing flowchart from the SysML design model to the safety analysis and verification process.Finally,the model diagrams of SysML and the components of the AltaRica 3.0 model are analyzed in detail.(2)The semantic equivalent transformation rules from the core model elements of the SysML architecture model to the latest system safety modeling language AltaRica3.0 are constructed and analyzed for correctness.Firstly,the model characteristics of SysML and AltaRica3.0 modeling are analyzed.Then the mapping rules between SysML model elements and AltaRica3.0 model elements are constructed,including the core transformation rules and how to extend the fault grammatical semantics of SysML.Finally,the formal description of the rules and analysis are given to prove the correctness of the conversion rules.(3)Based on the model-driven approach,a prototype tool,SafetyTool,was designed to perform automatic model conversion and system safety analysis.The prototyping tool integrates functions of transformation,compilation,fault tree generation,fault tree analysis,single-step simulation,and fault path dynamic demonstration.It can automatically parse the XMI model of SysML,extract the required model elements,and automatically convert to the AltaRica3.0 according to the AltaRica syntax.Then the AltaRica 3.0 model file was subjected to a safety analysis.(4)The method and tool are shown by the example of the wheel brake system of the civil aircraft in the SAE AIR6110 standard.Including the SysML model of the wheel brake system based on the AIR6110 document standard and safety requirements,using SafetyTool to realize the conversion of two modeling languages,building a fault tree based on the AltaRica3.0 model,using the relevant tools to analyze the safety of the system,performing dynamic demonstration of fault path in a graphical manner,and last verifying the safety attributes of the wheel brake system.