Fault Diagnosis Method Study Of Automobile Engine Electronic Controlled System Based On Information Fusing

On the basis of extensive collection of automotive fault diagnosis study on home and on broad, the classification of basic theory and application of automotive fault diagnosis are present in this paper, and then analysis the key technologies of various periods and its character and development direction. Based on those, put forwards that the study direction would be using information fusing theory to study the automotive electric-controlled system fault, and adopting multiple pattern recognition method for character level fusing, the main content is shown as follows:At first, based on the analysis of present automotive fault diagnosis method, summarize the automotive fault mechanism and feature, put forward that the future automotive fault diagnosis method and technology would be the fusing of various advanced technology and theory which based on traditional method, and paying attention to feedback system, then, on the basis of analysis on information fusing theory's character and applicable condition, analyze the theory applicability for automobile diagnosis. The second, the basic theory and technology of pattern recognition and information fusing are studied in this paper, especially for D-S evidence theory and its key problems resolve method, including basic evidence reliability assignment, evidence conflict, relativity and how to assemble evidence on the different recognition frame, and then study the information fusing method based on D-S evidence theory, put forward that let the output value from low-dimension neural network as the basic reliability assignment, then through D-S evidence theory to fusing again until the final diagnosis result. The third, on the basis of study on automotive electric controlled system and its control principle and data flow, analyze the theory basis of reliability between sensor and actuator, sensor itself and actuator itself, those provide the basis for character fusing. The fourth, for parameter choosing, combination traditional method with kernel method, then according to the automobile fault requirement,from sensor and actuator, sensor itself or actuator itself to choose the best character parameter for diagnosis. The fifth, through diagnosis detection system, inspect the validity, and then study the precision problem. The experiment shows that, this method could promote the rate of accuracy on some degree, eliminate the single data source's one-sidedness and fuzzification and so on, then promote the precise efficiency.Automobile electric-controlled system fault pattern recognition based on NN and D-S evidence theory is the basic of establishment on integration and intelligent fault diagnosis, and relative theory' application study is the necessary condition for promoting the diagnosis precise, this method is not only the efficient method about intelligent diagnosis, but also the whole vehicle's electric-controlled system fault diagnosis's new quest, it would be promote the development process about intelligent diagnosis.