Development Of An Informationized Node Test Equipment With Fault Diagnosis And Prediction Function

With the continuous improvement of complexity,maximization,networking and intelligence on electronic information system,the test equipment has develop ed to the distributed test system of "distributed collection,centralized analysis management and sharing of data resources”.In the past,the node test equipment in the distributed test system could only inspect status without the ability to achieve fault diagnosis and prediction in usual.Furthermore,with poor universality,the test equipment should be produced in specialty according to the different requirements of the nodes,which leads to the high expenditure and difficult maintenance.In view of these w eaknesses,this research project aims to develop a general test equipment with ability of information interaction,fault diagnosis and fault prediction.Using this equipment to construct information distributed test system can improve the ability of test,fault diagnosis and prediction to complex electronic information system.In hardware design,all the test requirements of each tested node can be met by selecting high-integrated instrument module that has reusable terminals.Moreover,by using the instrument module with the terminal configuration function and the wide measuring range,the distribution and conditioning capability of Test Unit Adapter(TUA)can be replaced so that there is no need to develop the special TUA for test,which leads to the interchangeability,universalization and miniaturization of the node test equipment.Besides,the volume of the node test equipment has also been effectively reduced because of selection of highly integrated and portable PXI chassis.In view of the characteristics of electronic information system,the fault causes and symptoms are random and uncertain,the fault sample is lacked,the status information is limited and the priori information is multi-source and heterogeneous.On the basis of improving the Dempster-Shafer(DS)evidence theory to deal with the problem of conflict evidence,a method of fault diagnosis based on grey relational analysis and improved DS evidence theory is proposed.The method combines the advantages of grey relational analysis to deal with the few samples,poor information and uncertainty problems and the advantages of DS evidence theory to consider the uncertainty in the process of information fusion.In view of the trend with time of the random drift error of fiber optic gyroscope and the voltage of high power supply,a fault prediction method based on ARMA-Elman neural network is proposed.The method combines the ability of the ARMA model to fit the linear time series and the ability of the Elman neural network to map the nonlinear time series.The fault diagnosis method and fault prediction method are implemented in the form of components so that they can be called by node test equipment.The test software is developed based on the Joint Test Platform(JTP)of our department.By developing the components with the basic function to built the test schemes,the function of test software is realized.With the help of the information interaction service provided by JTP of our department,node test equipment can access each other,call each other and share the information.By developing the instrument resource component,the test data of the instrument module is informationized.During the development of fault diagnosis and fault prediction components,the framework of component to call the Matlab engine is written so that it is convenient to expand more algorithms in the future,which can improve the ability of fault diagnosis and fault prediction of component.Through calling the components developed in this project and the components in JTP of our department,the software of node test equipment with the ability of information interaction,fault diagnosis and fault prediction is built.Finally,the system integration test of software and hardware is completed.The informationized,remote test,fault diagnosis and fault prediction function of node test equipment is verified through the Virtual Unit Under Test(VUUT)and physical signal source.The result shows that the node test equipment developed in this project can meet the development requirements.