泛华测控.ppt

数据采集技术,北京中科泛华测控技术有限公司,,数据采集功能,,,,,,,,模拟输入/输出,数字输入/输出,时钟输入/输出,,ADC,DAC,cntr/timer,digital,DAQBoard,,,,插入式数据采集卡的优越性,,灵活费用较低性能选择范围大大量的软件工具可用利用PC技术,数字化技术,信号分类,信号根据其所传递的有用信息进行分类,信息,状态,速率,幅值,形状,频率,Signals,Analog,Digital,On-Off,TimeDomain,PulseTrain,FrequencyDomain,,,,,,,,,,,,DC,,,,,,,,数字信号,开关信号,连续脉冲信号,ReadanopticalencoderOutputGenerateasquarewave分辨率时钟频率,SenseaswitchclosureOutputCloseavalve驱动程序的功能通道数,DAQ卡需要考虑的指标,,,数字信号调理,,LoadsRequiringACSwitchingorLargeCurrentFlow,,ProductionMonitoringorProcessControl,Common-ModeVoltagesorHighVoltages,,ElectromechanicalRelaysorSolid-StateRelays,,OpticalIsolation,,,,,,,,,,,SolenoidsValvesMotors,HeatersLampsPumps,ElectromechanicalRelaysorSolid-StateRelays,ProximitySwitchesLimitSwitchesThermostatsManualSwitches,数字I/O,,,模拟信号,,时域信号,VibrationSpeechSonar分辨率采样率AC精度触发滤波器,TemperaturePressureFlowStrainDC精度,频域信号,直流信号,ECGBloodpressureSingle-shoteventsChromatograph分辨率采样率AC和DC精度触发,DAQ卡需要考虑的指标参数,,,模拟信号调理,,低电压信号,,电流输入/输出,,RTDs和热敏电阻,热电偶,应变仪,隔离放大噪声滤波,电流与电压的转换;隔离，放大，噪声滤波,隔离，放大，噪声滤波冷端补偿,,,,,激励电源隔离，放大，噪声滤波,,,,激励电压全桥和半桥设置隔离，放大，噪声滤波,,,,,,,多功能I/O,,,Demo,变送器/传感器,物理现象传感器温度热电偶RTDIC传感器热敏电阻光真空管光电传感器声麦克风力和压力应变仪压电传感器,热电偶,价格较低，坚固可承受高温可迅速感知温度的快速变化需要作冷端补偿电压量很小需要放大输出非线性需要冷端补偿,,RTDs,精度比热电偶高不需要冷端补偿比热电偶昂贵需要电流源非线性输出，需要线性化2路RTDs接线，简单，但要考虑接线电阻误差3路和4路RTD接线，消除了接线电阻误差,,热敏电阻,需要电流源或电压源激励非线性化强烈，需要线性化敏感度高电阻高,,应变片,需要电压源需要桥式电路设置非线性化输出，需要线性化,,DAQ卡的前端信号调理模块,SignalConditioningeXtensionsforInstrumentationSCXI,SCXI选择,信号调理多路复用放大隔离滤波传感器激励冷端补偿,SCXI的其它特性,可扩展，最多到3,072通道紧凑，在7英寸空间可达384个通道灵活，可以和最新的采集卡，软件，和计算机配合工作高速，和E系列的采集卡配合扫描速度达333KHz设置方便结构开放,Demo,A/D分辨率,,,Codewidthsmallestdetectablechangeinvoltage,,AD的输入范围,增益*2,n,,nofADCbits,,,16-bitADC,3-bitADC,Amplitude,codewidth,,,,,Time,0,20,100,120,140,40,60,80,10.009.757.506.255.003.752.501.250,111110100011010001000,A/D采样率,,Nyquist原理采样率2倍的最高频率,Adequatelysampled,Aliasedduetoundersampling,,,,,,,,,,,,,,,,,,,,,,,多通道采集,采集模式,通道设置,扫描顺序增益范围单端/差分输入单极/双极,连续扫描同步采样间隔扫描,Straingauge1Straingauge2,Battery1Battery2,TempPressure,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,Demo,实时系统集成总线RTSIReal-TimeSystemsIntegrationBusRTSI,在板卡之间连接时钟和触发信号完成数据采集的同步操作在DSP卡串行传输数据,触发,软件触发,条件获取软件由AIBufferRead设定AIRead调用AIBufferRead,模拟触发,数字触发,Demo,,应用软件,,,,接口软件,软件,LabVIEWLabWindows/CVIComponentWorksVisualBasicC/C...,PCI-MIO-16E-1,DAQ卡,NI-DAQ,要求可以所有采集卡的功能向下兼容通用的API功能齐全的设置工具方便易用,DAQ的软件接口,,,,NI-DAQ,ApplicationSoftware,,Demo,软件开发平台选择,,,,VirtualBenchReady-to-RunVirtualInstruments,VirtualInstrumentsScopeDynamicsignalanalyzerArbitrarywavegeneratorFunctiongeneratorDMMDatalogger,Demo,软件开发平台,GraphicalProgramming,VisualC,LabWindows/CVI,VisualBasic,,,GraphicalProgrammingLabVIEW,EmpoweringtechnologyNaturalflowchartnotationEliminatessyntacticaldetailsReducesdevelopmenttimeRapidprototypingSelf-documentingIntuitiveandeasytolearnIdealforcodereusabilityModularityandhierarchy,Demo,WhatisMeasurementStudio,MeasurementHardware,LabWindows/CVI,MeasurementStudioToolsforVisualC,Compilerintegration,IntellisenseClassWizard,,VisaGPIBAnalysis,,ApplicationWizard,MeasurementclassesAcquisitionAnalysis,UserinterfacethroughActiveXUtilityclassesDataobjects,MeasurementStudioToolsforVisualBasic,MeasurementandautomationActiveXcontrols,,,LabWindows/CVI,,ANSICStandardLanguageCompilerEditorDebuggerOpenSystem,Built-inInstrumentationLibraries,ProductivityToolsforfasterdevelopment,StandardANSICLanguageOpen,powerfulMultithreaded,,Demo,