Research And Design Of Automotive Fault Diagnosis System Based On Fault Tree And Case-based Reasoning

With the rapid development of economic and modernization of social, the scale of automobile’s production are increased widely, and the use of automobile are also more widely. Use fault diagnosis system can help automotive repair business to diagnose the cause of the malfunction quickly and efficiently when the car has faults, and repair the faults in time, so as to ensure the safety and reliability of the car. The traditional a single model of fault diagnosis cannot meet the needs of made diagnosis clipping and accurate, because of the complexity structure of the car and many kinds of faults, Therefore, this article gives an automotive fault diagnosis system based on the fault tree and case-based reasoning.Firstly this article describes the principles and characteristics of expert system fault tree analysis and case-based reasoning, Analysis of the benefits of automotive fault diagnosis system application fault tree and case-based reasoning technology. Secondly describes the methods and procedures of the establishment of fault tree, the mathematical representation of the fault tree and the method about qualitative and quantitative analysis of the fault tree. At the part of knowledge’s acquisition, representation and storage:This system use fault tree model for knowledge’s acquisition, fault tree are stored in relational database, And changes the rules storage method to rules plus framework, that can integrate the knowledge and case examples in a database. It is the basis of built fault diagnosis system.At the part of reasoning:Use the method that fault free reasoning combined with case-based reasoning, use fault tree method based on the minimal cut sets probability of occurrence to forward reasoning the fault phenomenon on a regular, if you cannot find the cause of the fault then transfer to the matching case-based reasoning which is the focus of this study.Finally, the knowledge database, inference engine and the overall structure and the functional based on the fault tree and case-based reasoning modules are analyzed and designed. The function of some of the modules are realized, Proved that use fault tree and case-based reasoning theory to expert systems has a good practical value, can improve the efficiency of the expert system.