Fault Diagnosis Expert System For One Type Aero-engine In Our Army

The design and implementation of fault diagnosis expert system foraero-engine is discussed deeply in this paper.Expert system is make use of a great deal of skill area expert ofexperience knowledge and certainly reason logically a kind of artificialintelligence calculator procedure that the method solves the complicatedproblem, it be advantageous to save and expansions to diagnosis expert ofprecious experience knowledge, be free from the influence of the factors,such as time and environment...etc., have the important function in faultdiagnosis and maintenance.This text base on the characteristics of aero-engine's fault model, framemeans the method and fault tree according to the aviation, putting forwardwith binary fault tree conduct and actions transition, using to fault tree toestablish the aviation engine fault diagnosis expert system knowledge basenew method. The importance that the tree method conduct and actions faultdiagnostic kind of basic method according to lie in, the original techniquedata that aero-engine system provides to mainly fault ,the fault tree of thephenomenon to diagnosis the method, and through long-term of actualapplication these diagnosis accuracy and credibility of method to havealready got the full certificate have the very high exploitation value.Therefore, diagnosis method is used to from the fault tree that the originaltechnique data provide for whole diagnosis system a kind of basic faultdiagnosis method, at the same time in consideration of this part fault treediagnosis knowledge overlaid only limited several kinds of faultphenomenon, so built up the fault tree of additional part to diagnosis modeltowards diagnosis object further made the fault mechanism analysis, insystem develop process, thus expanding the whole fault of system tree thediagnosis knowledge. The Binary tree is a kind of tree, its characteristics iseach node can have two sons trees at most , and the son tree contain thesequence of left and right, the order can't be reversed arbitrarily. Make useof binary trees can be easily expressed and processed , we cantransform generally first to fault tree for binary fault tree, then convert intothe knowledge base of the expert system, thus carrying out to fault treecombine with the expert system. The left son tree of the binary fault treeuse to save the phenomenon of the next class node, namely to this nodeaffirmative the answer step ;The right son tree uses to save this node togetherthe class fault phenomenon, the step of negative answer to this node. The system builds up the diagnosis knowledge base of the system ingather together a certainly engine usage of the professional technicalpersonnel and support, managing the foundation of experience andknowledge, building up to gather the function adjustment and fault diagnosisand the literature manage the expert system that imbeds in automaticexamination equipments in the whole body. The expression of knowledgeadopt fault tree frame structure and the creation types combine together. Theknowledge in the knowledge base usually is according to the knowledge tomean the form, property, layer, contents to organize , constituting thestructure of the knowledge base. Adopt the mode of the knowledge base andsystem separate, can increase the technical personnel's experience andknowledge to the expert system knowledge base expediently, enrich theknowledge of the knowledge base continuously, increase the accurate rate ofdiagnosis. A system that owned a great deal of knowledge still can't resolve theprofessional realm problem, it must have the ability of the applied knowledge,it is reasonable ability. Reason mechanism is a certain search strategychoose the relevant knowledge from the knowledge base, carry on reasoningcontinuously towards have already know , until get a conclusion. Thereasoning machine carries on reason using the knowledge in theknowledge base and the fact that customer provide ,from the already knownto the new fact. Then the beginning fault state of database or the fault stateof the dialogue between personal and machine , carry on the search andreason logically and match to the knowledge. It is mainly made up ofattemper procedure and explaining procedure. Reasoning machine is theexpert's thinking mechanism, namely expert analysis problem, solve problema kind of calculate way of method and the machine realization. The systemadopts the search strategy of the certain reasoning and uncertain reasoningcombine together , not only lowered the spot personnel's usage difficulty,but also raised to reasoning the efficiency. Simple reasoning is certain reasonestablished on the classic logic foundation, this is the precision that a kind ofusage assurance knowledge carry on to reason logically. It is certain...