high channel count daq presesentation
DESCRIPTION
Presentation given at NIWeek2009 on Scalable High Channel Count Data Acquisition SystemsTRANSCRIPT
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High Channel Count to a Single Channel,a Scalable PXI Based Dynamic Signal
Acquisition System2009 NI Week – August 4th
Doug WilsonStephen MasulloPVI Systems, Inc.
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System OverviewSingle or Multiple Chassis w/ControllerGPS Synchronization
Excitation DevicesTransducers
GigESwitch
Host Computer
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Development Overview• Scalable Data Acquisition System
Designed for a Government Lab Advanced DAQmx Help from NI S&V Support Group
• Design Goals Flexible Data Acquisition Engine Scalable Reconfigurable to Support Multiple Test Programs Geographically distributed
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Functional Capabilities•Channel Configuration Management •Hardware Setup and Control•Data Quality Checking•Data Monitoring•Data Streaming•Frequency Processing•Data File Management•Automated Acquisition
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NI Hardware – PXI or PXIe
Chassis with Controller
Timing Card(s) Data Acquisition Modules
Embedded
Or
External
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Timing Synchronization Options
GPS
Master/Slave Configuration
Master Slave #1
Slave #2
GPS
All Master Configuration
External Clock
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High Channel Count Expansion Options
Slave #2
Slave #6 Slave #7
Master
Slave #1
Slave #4 Slave #5
Slave #3
Slave #8 Slave #9
Master/Slave Expansion
Chassis #1
GPS
Chassis #2
GPS
Chassis #3
GPS
Chassis #4
GPS
Chassis #N
GPS
All Master Expansion
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Software Flow Diagram
Host Main
Server Main
Source Control
Acquisition Control
Data Monitoring
Data Plotting
Data Export
Data File Download
Acquisition Hardware
TCP Messaging
Channel Config Utility
Data Streaming
Host Side Server Side
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Acquisition Control Initialization
• NI-Sync Timing• DAQmx Init• Trigger Init• Sync Pulse Init (on Master Chassis only)• Connect Start Trigger
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Acquisition Control - Acquisition
Init Circ BufferStart DAQmx TasksIssue Start Pulse
Acquisition Loop
Data Monitor Loop
Circular Buffer→ RMS→ Peak →Host→ Waveform
DAQmx ReadWrite to Circular BufferWrite to TDMS (if logging)
AI Start
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Data Formats• Time Data – TDMS File on Each Server
Configuration for All Servers Scaling Coefficients Raw Data Recorded Errors
• Frequency Data – TDMS File on Host Configuration for All Servers Selected Frequency Data (PS, PSD, FRF) Recorded Errors
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Software Design – Host Main
• Acquisition Functions• Configuration Utility• Source Control• Acquisition Control• Signal Monitor
• File Functions• Data Plotting and Freq Processing• Download / Merge Data Files• File Export• File Configuration and Error Display
• Utilities Functions• View Time of Master Chassis• Reset Communications
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Configuration Management• Defines All Test
Parameters• System• Frequency• Analog Input• Analog Output
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Source Control• Output Waveform• Output Amplitude
Master Per Channel
• Sine Output Frequency• Coordinated Digital
Triggering with Analog Output
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Acquisition Control
• Data File Path• Acquisition Mode
Continuous Finite Frequency
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Signal Monitoring• Bar Graph Indicator
Max RMS Instantaneous Peak
• Range Setting Per Channel Auto Range All Chan
• Per Channel Time or Frequency Display
• Multi-Plot• Error Indicators
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Frequency Processing• Time Data Streamed to Disk• Frequency Processing on Servers
• Results transferred to Host• Display Parameter Control
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Time Data Display• Playback from TDMS File• Full Time History• Windowed Time Display
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Frequency Data Display and Processing• Playback with
Frequency Processing• Selectable Parameters
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Automated Acquisition Control• Programmatic Control - Active-X• Update Front Panel Controls• Generate Events• Control entire experiment
multiple acquisition & source setups
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Future Development
• Expanded Range of Validated NI Hardware• Enhanced User Interface• Integrated Post Processing Tools• Interface to Third Party Post Processing Tools
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System Demonstration
• Demonstrates Multiple PXI Chassis Configuration• Live Linear Acoustic Array Data Streaming• Live Processing
See the live demo atPVI Systems Booth # 433