The Design And Realization Of Data Logger For A Measurement System

In aerospace testing system, data logger has become an indispensable part, it is used toobtain many important parameters in the process of aircraft in flight，and provides reliableexperimental basis for the fault analysis, performance evaluation and design improvement ofproduction for the whole aircraft system. This paper design and realize the data recorder isused for completing the acquisition of analogs and reception of digital. After the experiment,data logger can be retrieved hardly, and the testing data could be read out and analyzed.Aiming at data logger’s development at home and abroad, according to the design ideasof modularization and miniaturization, and combined with the data logger task requirementsand performance indicators, and put forward the overall design scheme of data logger and keytechnical solutions, and analyzed the hardware function modules and the design of the FPGAlogic sequence. The data logger hardware design is divided into three parts, the acquisitioncard, memory card, and the power card. Acquisition card controlled the AD conversion chipADS8365for receiving six channels analogs, through the RS-422interface circuit receives theone road PCM stream data, through the Optocoupler isolation circuit receives one road offsignal. Finally, The FPGA main control unit will encode analog, the PCM data and off signalin a mixed frame format, and frame data is sent to memory card by the circuit board connector.Memory card received the frame data, and FPGA main control unit will encrypt these dataand write in data logger storage unit. Samsung4G NAND FLASH chip is used as a datalogger storage unit. Data logger adopts LVDS interface technology to communicate with theground of reading monitoring devices, upload data recorder working state and data in storageunits to the ground computer.Finally, this paper tested the data logger’s function, analyzed the test results. System test results indicates that the data logger can accurately acquisition six channels analog, thesampling rate is60KHZ, receive10Mbps rate of PCM data, LVDS communication interfacerate can be up to20MB/S.