Research On Safety Analysis Technology Of Civil Avionics Architecture

The concept of safety directed development is the most important characteristic of civil aircraft avionics system development.The integrated modular avionics system has put forward a higher request on safety due to its high integration of hardware and software,modularity and intelligence.Therefore,it is very necessary to study the safety analysis technology of civil aircraft avionics system architecture,which is of great significance to the establishment of the safety guarantee system of our air transport industry.In this thesis,based on the thorough study of the safety analysis process and safety analysis technology of civil aircraft avionics system,a safety analysis solution is put forward.(1)A model based architecture safety analysis method is proposed.In order to solve the problem of low efficiency and low accuracy when applying the traditional fault tree analysis method to the safety analysis of large complex avionics system,the avionics system architecture is first extended to form a safety analysis model,based on which an automatic modeling method of fault tree is put forward through path tracing.This thesis also provides common mode analysis and zone safety analysis methods based on the fault tree.(2)An architecture safety comprehensive evaluation method based on D-S/FAHP is proposed.In order to evaluate every aspect of safety,and solve the fuzziness and uncertainty in this process,D-S evidence theory and FAHP method are introduced.The architecture safety comprehensive evaluation based on D-S/FAHP is conducted on a safety comprehensive evaluation model.The fuzziness and subjectivity of the qualitative factors measurement process is fully considered through transforming the inconsistency information of the pairwise comparison matrix into the uncertainty of the evidence.Afterwards,considering the safety appraisers' reliabilities,the evidences corresponding to different safety appraisers are fused,thus obtaining a more comprehensive and reasonable result.(3)An avionics system architecture safety analysis tool is designed and implemented.An avionics system architecture safety analysis tool is designed and implemented by applying theory into practice,which can analyze the avionics system architecture automatically,thus making the safety analysis more efficient.