Research On Reliability Analysis Of Main Landing Gear Retracting System Based On Fuzzy Evidence Network

Reliability analysis of civil aircraft is the basic work of modern civil aviation safety operation.The main landing gear retractable system,as an important part of civil aircraft landing gear,plays a vital role in ensuring the safe takeoff and landing of the aircraft.When the retractable system fails,it will have a significant impact on the safe operation of the entire aircraft,so the reliability analysis of the retractable system is of great significance in ensuring the safety of civil aircraft flight.In this paper,for a certain type of civil aircraft main landing gear retractable system,the dynamic fault tree analysis method is first used to establish the dynamic fault tree model of the retractable system to fully describe the dynamic characteristics of the system when the fault occurs;secondly,the fuzzy theory is used Determine the failure rate interval of the event at the bottom of the fault tree,introduce evidence theory to describe the failure rate data,use the evidence network integrated into the graph model to simplify the calculation process and make the model graph more intuitive,and add time series analysis to the evidence network The trend of the reliability of the retractable system over time is shown.Finally,based on the evidence network diagram and node failure rate of the retractable system,the reliability interval and roots of each time period of the retractable system are calculated using the two-way reasoning advantage of the evidence network The importance interval of the node,and at the same time determine the weak link of the retractable system according to the calculated importance parameter,thus completing the overall reliability analysis of this paper.In this paper,the fuzzy evidence network reliability analysis method is used to solve the problems of dynamic feature description when the system fails,the uncertainty expression of the failure rate of the bottom event,the complicated calculation of reliability analysis,and the reliability trend of the system over time.Finally,the article also establishes a graded impact table for the diagnostic importance and probability importance of inference calculation,which can provide recommended decisions and guidance for staff’s dailymaintenance and repair work.