多通道混合数据采集系统设计与实现

Design and Implementation of Multi-channel Hybrid Data Acquisition System

静爆试验中需要对各测控点上多个前级差分式梳状激光光幕探测器输出的多路模拟数据进行采集,针对前级设备通道数多,时间精度高且数据量大,后期难处理的问题;设计了一种具有自治能力的混合数据采集系统,该系统能自动剔除无效数据,将破片过幕时所产生的弹形信号及该弹形信号对应的UTC时刻值组成的混合信号缓冲并传输至上位机;该系统采用FPGA+ARM的架构完成采集缓冲任务,根据上位机配置T S和V m阈值自动剔除无效数据,结合GPS驯服温补晶振的手段使本地时钟与UTC时钟保持μs级同步,并对采集弹形模拟数据进行UTC时钟打标形成混合数据包,通过USB2.0总线高速模式传至上位机;经实际测试该设计满足静爆试验中对前级探测器输出信号的采集需求,数据量大大减少,UTC时标精度满足后续处理要求并且成本低廉,稳定性高。

The static explosion test needs to collect multiple analog data output from multiple front-stage differential comb-shaped laser light curtain detectors at each measurement and control point.For the front-stage equipment,there are many channels,high time accuracy,and large data volume.A hybrid data acquisition system with autonomous capability was designed.This system can automatically remove invalid data and buffer the mixed signal composed of the bullet-shaped signal generated when the fragment passes through the curtain and the UTC time value corresponding to the bullet-shaped signal.And transmitted to the host computer.The system uses the FPGA+ARM architecture to complete the acquisition buffer task,automatically remove invalid data according to the configuration of the host computer and the threshold value,combined with GPS to tame the temperature-compensated crystal oscillator to synchronize the local clock with the UTC clock,and perform UTC on the collected bullet-shaped analog data The clock is marked to form a mixed data packet,which is transmitted to the upper computer through the USB2.0 bus high-speed mode.After actual testing,the design meets the requirements for the output signal of the front-stage detector in the static explosion test,the data volume is greatly reduced,the UTC time stamp accuracy meets the subsequent processing requirements,and the cost is low and the stability is high.