Fast Export And Effective Data Extraction Of Intelligent Vehicle Operating Data

Quickly exporting and extracting the data of the vehicle driving state recorder（black box）is an important prerequisite for analyzing the driving state of the vehicle and diagnosing faults.With the improvement of modern automobile electrification and intelligence,With the improvement of modern automobile electrification and intelligence,the number of vehicle electronic control units has increased,and the data stored in the black box has also increased sharply.The traditional data export and extraction methods are difficult to meet the requirements of intelligent vehicles.After studying various data processing and transmission methods,this paper designs a new wireless export system based on a domain controller with stronger computing power.The new system includes data compression,transmission and extraction.The main work is as follows:（1）Analyze the data acquisition and storage characteristics of automobile black box and the specific requirements of driving state analysis for data format,study the key technologies of black box data export and extraction,design the scheme of data export,and give the idea of data extraction;（2）According to the data export scheme,select the relevant hardware modules based on the domain controller to construct the data acquisition and communication platform.According to the characteristics of data fragmented storage,file merging and LZ4 compression steps are performed before FTP transmission.In order to optimize the compression effect,modular data preprocessing is carried out while the files are merged According to the different redundancy types of each part of the data,it is divided into three modules: time,data source and data;（3）In order to ensure the accuracy of log playback,according to the format characteristics and requirements of driving data,the host computer is used to further process the log data exported to the local.Using data frame DLC and ID white list to quickly eliminate error frames;In addition,based on the hook-Jeeves search method,a variable step size search method is proposed,which uses the pointer jump in the file to avoid the calculation of invalid frame data and quickly retrieve the data in the time interval set by the user;（4）The log data export and extraction system is developed by using C++ programming under Linux system and MFC platform under Visual Studio the SVDC intelligent domain controller test platform is constructed in cooperation with an intelligent vehicle R ＆ D team.The new data export and variable step search algorithm are verified.The experimental results show that the system can meet the requirements.