Research On The Fault Diagnosis Technology Of G1000Avionic System

Along with the rapid development of electronic and computer technology, mostof the modern civil aircraft avionics systems are highly digital, modular,integrated andintelligent devices. The integrated avionics system go with the complicated structure,mass data transimission and variable correlative faults. So it is difficult to localizefaults and to guarantee the accuracy and efficiency of the avionics system faultdiagnosis. Especially in the case of multiple faults, the propagations of correlativefaults caused large difficulty for the failure diagnosis procedure. So the research onthe integrated avionics system is always a hotspot issue.The model of G1000avionics system was selected for study to simulates themaintainer’s mentality and work flow to carry on the integrated avionics systemdiagnosis, and unifies the experience knowledge of the experts with the theoryknowledge in technical manual, the inference from diagnosis case with the inferencefrom the diagnosis tree.The knowledge characteristic of this fault diagnosis system was analyzed in thispaper. The suitable knowledge expression method were chosen after that. The faultdiagnosis system knowledge liabrary of G1000avionics system were established atlast.According to the whole design plan of this fault diagnosis system, the concretesoftware architecture plan was realized by VC++language and Microsoft Accessdatabase. After validity check on the system, it was confirmed that the system hasachieved the anticipated design goal.The main work of this paper has been focused on several aspects: First,according to the structure of crosslinked the G1000, maintenance information and lotsof specific maintenance works, therefore the knowledge database of the G1000isbuilt by Access databases,classified the fault information to draw the subsystem’sfault trees；Second, the characteristic of these fault trees were analyzed to design theknowledge base and inference engine, then the general design of G1000faultdiagnosis system was set up; Third to obtain the fault knowledge base of G1000by using Access databade and VC++language as a programming language for softwaredevelopment tools to achieve the software implementation, furthermore this systemwith updates, security management functions.The design of knowledge database has resolved which was the key technology inthis paper. Meanwhile the strengthen expanding of the knowledge base, which makesthe system has the characteristic of framework system concurrently, and benefitsgradual completion of the system for application.