多通道振动传感器高精度同步采集方法  

High Precision Synchronous Acquisition Method of Multi-channel Vibration Sensor

作　　者：刘鹏 王茜 王西泉 李鹏勃 LIU Peng;WANG Qian;WANG Xi-quan;LI Peng-bo(Test and Measuring Academy of China Ordnance Industries,Huayin 714200,China)

机构地区：[1]中国兵器工业试验测试研究院,陕西华阴714200

出　　处：《计算机技术与发展》2022年第1期170-174,共5页Computer Technology and Development

基　　金：国防基础科研计划资助(JCKY2016208A006)。

摘　　要：复杂结构体在高速运动时受力复杂,分结构之间的受力互为耦合,结构体多点位振动数据的高精度同步采集对结构体力学仿真和仿实一致性分析至关重要。为满足结构体高速运动时振动数据的高精度同步采集,基于AD7656+FPGA的设计思路,该文使用主控芯片FPGA产生一组采集控制信号,同时对8片AD7656进行控制,确保各片AD7656间的同步精度,同时为提高回读速度,采用三DOUT输出模式,大大降低FPFA的资源要求和布线难度,对同一时刻采集的48路振动传感器数据,按照遥测帧格式,编成一个数据帧,形成PCM码流,通过遥测发射机实时发送至遥测地面站,通过遥测地面站对数据进行实时显示和存储;设计了同步采集精度实验室验证方法,使用一台高采样率的数据采集设备同时对采集触发信号、片选信号、8个AD时钟信号进行采集,通过对比片选信号后的第一个时钟信号的相位差,就可以测量出8片AD7656之间的同步采集时间精度。最终验证的多路同步采集时间精度小于1μs,可满足系统设计的要求。该方法已实际应用于相关试验测试。The force of complex structure is complex when it is moving at high speed,and the forces of sub structures are coupled with each other.High precision synchronous acquisition of multi-point vibration data is quite important for mechanical simulation and simulation consistency analysis of structure.In order to meet the high-precision synchronous acquisition of vibration data when the structure is moving at high speed,based on the design idea of AD7656+FPGA,we use the main control chip FPGA to generate a group of acquisition control signals,and control eight AD7656 to ensure the synchronization accuracy among them.At the same time,in order to improve the read back speed,three DOUT output mode is adopted,which greatly reduces the resource requirements and wiring difficulty of FPFA.48 channels of vibration sensor data collected at the same time are compiled into a data frame according to the telemetry frame format to form PCM code stream,which is sent to the telemetry ground station in real time through the telemetry transmitter,and the data is displayed and stored in real time through the telemetry ground station:A high sampling rate data acquisition device is used to collect trigger signal,chip selection signal and eight ad clock signals at the same time.By comparing the phase difference of the first clock signal after chip selection signal,the synchronous acquisition time accuracy between eight AD7656 can be measured.Finally,the multi-channel synchronous acquisition time accuracy is less than 1μs,which can meet the requirements of system design.This method has been applied to the related test.

关 键 词：AD7656 多路同步采集 振动传感器 遥测 FPGA 

分 类 号：TP212.9[自动化与计算机技术—检测技术与自动化装置] TJ06[自动化与计算机技术—控制科学与工程]