Development And Application Of Automotive Fault Diagnosis System Based On ODX

At each stage of the development of a diagnostic function,the description files of diagnostic data are different due to the different development environments.It is difficult to exchange the diagnostic data with each department.Different departments need to convert diagnostic data into their own available data formats Diagnostic data will be lost or even mistaken in the process of conversion,which will lead to the repeated development of diagnostic functions.Based on the diagnosis requirement of a certain company,this thesis presents the development of an automotive diagnostic system based on ODX standard database.Firstly,the needs of the automobile diagnosis are analyzed and a detailed system scheme is designed.The system consists of five parts: ODX database,remote server platform,diagnostic application program,system configuration tool and MVCI protocol module.Secondly,through in-depth study of ISO22901-1,we extract all diagnostic related data in ODX data database,these diagnostic data is stored in a designed relational database,and the relational database content is filled out in Excel.Establishing UML model of standard ODX database through VS2015 to generate a standard ODX database template.Then we develop a configuration tool to extract the diagnostic data from Excel and import it into the ODX database template to complete the creation of the standard ODX database.Thirdly,we develop the core D-Server of the remote server platform,D-Server is the actual executor of the diagnostic function in this system.The D-Server API is a standardized interface to the D-Server based on ISO22900-3,which is designed to implement communication between the diagnostic application program and the D-Server through the HTTP protocol.To complete the functions of each D-Server API,the D-Server is designed to be divided into four processors,which are communication processor,data processor,flash data processor and job processor.Then,diagnostic application and process configuration tool are developed.Diagnostic application is used to provide user interface operations.The process configuration tool encapsulates various diagnostic services and stores them in the corresponding job library in java format.When the user configures the order of each diagnostic service,the tool generates the required job file by combining the encapsulated various java files.At the same time,in order to ensure the security of the system,the use of the license verification mechanism and third-party renewals system for user authentication to ensure the safety of the system.Finally,the various components of the system are tested and verified.The result shows the functions of each part are effective and reliable,it meets the needs of various usage scenarios.