Reliability Analysis On Multi Mechanism Coupling Fault Behavior Of One Spacecraft Transmission

As a link between the power system and the working mechanism,the transmission device is widely used in various types of aerospace vehicles.The wide application of the transmission device in the aerospace field brings forward a high demand for the reliability of the transmission device.Spacecraft transmission system has complex structure,wide application range,large number of parts,and large probability of fault,so its reliability is particularly important.In order to improve the reliability of the spacecraft transmission,the theory of mechanical reliability should be further improved so that it can be more close to the engineering practice.There are several kinds of coupling relations in mechanical reliability,including the coupling relation among random variables in the reliability calculation model,the fault mechanism and the coupling relationship among the fault behaviors.According to this,this paper takes a type of spacecraft integrated transmission device as the object of study,in the reliability analysis of transmission device and related components,considering several kinds of coupling relationship contains the mechanical reliability,the reliability of mechanical product analysis to maximize product reliability level are consistent with the real.The research contents of reliability analysis of transmission device fault coupling are as follows:(1)The Copula function is introduced into the reliability theory of mechanical system,the establishment of mechanical parts based on Copula function of stress-strength interference coupling calculation model,and a connecting rod driving device in reliability calculation of reliability interval gives the connecting rod parts,should be proved without considering the reliability level of Reliability stress coupling the parts are often higher than the actual unit.(2)A reliability calculation model of general mechanical system based on weight voting system is proposed,and Copula function is used to characterize the coupling relationship between life variables of each element in the system.Based on the inclusion exclusion principle,a reliability calculation model for two types of unit elements and a general mechanical system with different unit types is established.(3)Put forward based on Quality Function Deployment(QFD)technique of multi mechanism coupling fault behavior reliability comprehensive configuration method,this method by matrix operation to establish a comprehensive housing configuration reliability,realize the reliability index allocation system reliability index to unit fault behavior,in order to determine the weak links of the system,according to the design parameters of the weak link the unit was improved.(4)A spacecraft driving device as the research object,the transmission device was analyzed by FMECA analysis and FTA,obtaining the coupling coefficient matrix of fault behavior of sub transmission system using the DEMATEL method,and established the reliability allocation house drive device,the system reliability index assigned to each unit in fault behavior.The first time inverse reliability method is used to complete the configuration design of the diameter design parameters of the shaft unit of the speed changing mechanism.