遥测数据记录器单元测试的关键技术研究

发布时间：2019-04-01 10:15

【摘要】：在飞行器的遥测试验中,我们通常使用数据记录器对飞行器的工作状态参数进行记录,在飞行器落地后,我们将采集到的数据上传至计算机,用于分析数据和改进飞行器的设计。每一次飞行试验都会耗资巨大,为了保证数据记录器工作的可靠性,我们需要在它出厂前进行多次严格、全面的性能测试。基于对数据记录器性能的测试,设计了地面信号测试台,由于两者在接口上属于对应的关系,因此数据记录器和测试台应该共同开发,两者共同构成了单元测试系统。由于数据记录器需要在高温高压的工作状态下准确的记录信息,因此设计了以nand flash为存储介质的双备份存储电路,并分别通过缓存设计、纠错设计、均衡损耗设计和坏块管理来实现nand flash的控制优化设计。为了验证数据记录器采集模式的功能性,测试台模拟外界信号向数据记录器发送模拟量信号和PCM数据流,记录器将模拟量信号通过AD转换后,与PCM数据以一定的格式进行混合编帧,并行存入到两片nand flash中。在数据记录器的工作过程中,还会有一路RS-422信号,实时反馈数据记录器内部的工作状态,方便了我们对它状态的了解。记录器的下载模式由一路RS-422指令接口和一路LVDS下载接口构成,测试台发送完下载命令后,根据内部缓存的半满标志来向记录器发送忙闲状态,记录器根据接收到的状态信息控制数据的发送。下载数据采用8B/10B编码,并使用驱动芯片,实现了数据的长线传输。由于在以往的设计中,数据下载的速度较慢且较为固定,因此使用这种具有自适应下载控制的设计提升了测试台接收数据的速度,为单元测试节省了宝贵的时间。本文针对数据记录器的两种工作模式的关键技术进行了研究,并分别对采集存储模式和下载模式进行了大量的测试,测试结果表明在单元测试过程中数据没有出现误码和丢数,数据记录器工作稳定可靠,设计具有可行性。
[Abstract]:In the telemetry test of an aircraft, we typically use a data logger to record the status of the aircraft's working state parameters, and upon landing of the aircraft, we upload the acquired data to the computer for analysis of data and to improve the design of the aircraft. Every flight test will cost a lot. In order to ensure the reliability of the data recorder's work, we need to carry out a number of rigorous and comprehensive performance tests before it is delivered. Based on the test of the performance of the data recorder, the ground signal test board is designed, and the data logger and the test bench should be developed together because of the corresponding relationship between the two interfaces, which together form the unit test system. Because the data recorder needs to record the information accurately under the high-temperature and high-pressure working condition, the dual-backup storage circuit with nand flash as the storage medium is designed, and the control and optimization design of the nand flash is realized through the buffer design, the error correction design, the equalization loss design and the bad block management, respectively. In order to verify the functionality of the data recorder acquisition mode, the test bench simulates the external signal to send the analog signal and the PCM data stream to the data recorder, and the recorder then mixes the analog signal with the PCM data in a certain format after the analog signal is converted by the AD, and stores the analog signal in two pieces of nand flash in parallel. During the operation of the data recorder, there is also one path of the RS-422 signal, the working state of the real-time feedback data recorder is feedback, and the understanding of the state of the data recorder is facilitated. And the recorder sends a busy state to the recorder according to the semi-full flag of the internal buffer after the test board sends the download command, and the recorder controls the transmission of the control data according to the received state information. The download data is coded by 8B/ 10B, and the drive chip is used to realize the long-line transmission of data. Since the speed of data download is slow and fixed in the past design, the use of this design with adaptive download control improves the speed of data reception by the test table, and saves valuable time for unit test. In this paper, the key technologies of the two working modes of the data recorder are studied, and a lot of tests are carried out on the acquisition and storage mode and the download mode. The test results show that the data has no error and loss in the unit test process, and the data recorder is stable and reliable. The design is feasible.
【学位授予单位】：中北大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：V217;TP333

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