Dynamic Fault Tree Analysis For The IMA Core Processing System Of Civil Aircraft

IMA core processing system is an important part of advanced civil aircraft. Therefore, it isinevitable to tackle the safety criterion during the process of design. Due to these dynamiccharacteristics of IMA core processing system, such as fault tolerance, redundancy and sequentialcorrelation, the method of dynamic fault tree analysis is proposed to deal with the problem of safety.When this method is applied to the process of design, it can provide corresponding structure of IMAcore processing system with various safety levels of hosted functions, and then satisfy the requirementof safety.This thesis focuses on the function, the structure and the principle of IMA core processingsystem, and then comparatively analyzes characteristics of three principal components (GPM, AFDXnetwork and RDIU) of this system. Based on this analysis, different structures of component resourcesand hosted function LRUs are compared. Considering the dynamic characteristics of IMA coreprocessing system, dynamic logic gates are introduced to establish the dynamic fault tree with thehelp of conventional method. It is a kind of general dynamic fault tree solving methods, includingmodular decomposition method for the dynamic fault tree, binary decision diagram method for staticsubtrees and Markov state transfer chain method for dynamic subtrees. Combined with possiblefailure states of IMA core processing system, the fault tree model of the integrity and the availabilityof a variety of structures can be established. Then, these typical structures can be selected and solved,and the integrity and the availability of different structures can also be analyzed. Moreover, the matlabsimulation of IMA core processing system is carried out, based on models of GPM, AFDX networkand RDIU, the typical structure model can run. By setting modular failures, the fault-tolerant featureof this structure can be verified. Finally, linked with functions of fuel measurement and calculation ofthe fuel system, which is hosted in IMA core processing system, the results of simulation are tested tobe valid.