National Instruments at a Glance• Leaders in Computer‐Based          

Measurement and Automation

• Long‐term Track Record of  Growth and Profitability

• Record Revenue: $821M in 2008

• Fortune “100 Best Companies to Work For” ten years in a row

• FT 50 Best Workplaces UK 2006 ‐• FT 50 Best Workplaces UK 2006 ‐2009

• More than 5000 employees; operations in 40+ countries p

• Founded in 1976 with focus on Instrument Control

• LabVIEW 1 0 released in 1986

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• LabVIEW 1.0 released in 1986

Virtual Instrumentation“To do for test and measurement

what the spreadsheet did for financial analysis.”

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Virtual Instrumentation EvolvedEvolved

Test and MeasurementTest and Measurement Data AcquisitionData Acquisition

Automated TestAutomated Test Industrial ControlIndustrial Control

Embedded ControlEmbedded ControlDigital TestDigital Testgg

CommunicationsCommunications Medical DevicesMedical Devices

A d iA d i

CommunicationsCommunications Medical DevicesMedical Devices

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AcademiaAcademia

Acquiring Data With LabVIEW

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PC‐Based Data Acquisition (DAQ) 

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Data Acquisition Demo

Wi-FiEthernet

PXI Express

PXI

PCI PCI Express

USB

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PXI Express PCI Express

Measuring Analogue Input Signals

Important Factors to Consider:

•Architecture Multiplexed p

Simultaneous sampling

To PC

•Sampling rate

•Resolution Analogue Input…

Resolution

•Signal conditioning

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What is a Transducer?

SignalPhysicalPhenomena

Transducer orSensor

A transducer or sensor converts a physical phenomena into a measurable electrical signal that a DAQ system measures.

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What is a Transducer?What is a Transducer?Phenomena Transducer/SensorTemperature Thermocouples

Resistive Temperature Devices (RTDs)Thermistors

Light Vacuum tubePhoto sensorsPhoto sensors

Sound MicrophoneForce and Pressure Strain gages

Piezoelectric transducersPosition and Displacement Potentiometers

Linear voltage differential transformerOptical encoder

Fluid Head metersFluid Head metersRotational flowmeters

pH pH electrodes

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Signal ConditioningHigh voltage signals and most sensors require signal conditioning to properly

read the signal

Sensors/Signals

Amplification, Linearization, andThermocouples

Signal Conditioning

Cold-Junction Compensation, FilteringThermocouples

RTDs Current Excitation,Linearization, Filtering

Strain Gauges

ea at o , te g

Voltage Excitation, BridgeConfiguration, Linearization, Filtering

IsolationCommon Mode or High Voltages DAQ Device

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Analog Input – Architecturesg pMultiplexed

Channel 0

Channel 1ADC

Channel 0

Channel 1MUX AMP

Simultaneous sampling

Channel 0 ADC Channel 0AMP

ADCChannel 1Channel 1

AMP

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Analog Input – Sampling Ratesg p p g

• Undersampling may result in the misrepresentation of the d i l ( li i )measured signal (aliasing).

• After a signal is aliased, it is impossible to reconstruct the original signaloriginal signal.

• For accurate frequency representation:Sample at least 2x the highest frequency signal being measured.Sample at least 2x the highest frequency signal being measured.

• For accurate shape representationSample 5–10x the highest frequency signal being measured.

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Analog Input - Resolutiong p• 3-bit resolution can represent 8 voltage levels• 16-bit resolution can represent 65,536 voltage levels

16-Bit Versus 3-Bit Resolution(5kHz Sine Wave)

10.00

16 bit resolution can represent 65,536 voltage levels

6.257.508.75

Amplit de

16-bit resolution

3-bit resolution100

101

110

111

5.00

2.503.75

Amplitude(volts)

3 bit resolution

001

010

011

100

100 200150500Time (ms)

0

1.25000

001

| ||||

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Analog Input – Range and Analog Input Range and Amplification

ADC

10 mV signal 32 levels of resolution

ADC

Resolution: 16-bit Range: ± 10 V10 mV signal 32 levels of resolutionRange: ± 10 V

WITHOUT AMPLIFICATION

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Analog Input – Range and Analog Input Range and Amplification

65,536 levels of resolution,

AMP ADCX100

10 mV signal

ADC

Resolution: 16-bit Range: ± 10 V

WITH AMPLIFICATION

Range: ± 10 V

** Amplification optimizes resolution over the range of measurement **

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Accuracy versus Resolutiony• Resolution

A property of the ADC• Accuracy

A specification of the entire DAQ device t

A R

or systemIncludes many components and factors

• ADC nonlinearities• Temperature• System noise• Amplifier gain and offset errorsp g

• Higher resolution does not always equal more accurate!Look for Absolute Accuracy specification

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Grounding Issues• To get correct measurements you must properly ground

your systemy y• How the signal is grounded will affect how we ground the

instrumentation amplifier on the measurement devicep• Steps to proper grounding of your system:

– Determine how your signal is groundedDetermine how your signal is grounded– Choose a grounding mode for your Measurement System

M t S tSi l+

Measurement SystemSignalSource VS

-

VM

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Signal Source Categoriesg gSignal Source

Grounded Ungrounded

+

g

+

_Vs

_Vs

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Grounded Signal Source

Signal is referenced to a Signal Source

• Signal is referenced to a system ground

Earth groundGrounded – Earth ground– Building ground

• Examples:+ Examples:– Power supplies– Signal Generators

_Vs

g– Anything that plugs into a

grounded electrical wall socket

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Floating Signal SourceSignal Source

Floating• Signal is NOT referenced to a system ground gsystem ground

– Earth ground– Building ground

• Examples: +• Examples:– Batteries– Thermocouples– Transformers

_Vs

– Isolation Amplifiers

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Best Practices for DAQ: GroundingBest Practices for DAQ: GroundingFloating Signal Sources

(Not connected to Building or Ground)

Grounded Signal Source

Differential (DIFF)

Single-Ended-GroundReferenced (GRSE)

Single-Ended-Nonreferenced(NRSE)

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( )

What is noise?

• Noise is any unwanted signal that interferes with the desired signalg

Noise can be periodicNoise can be randomNoise can be randomUsually considered separate from drift and accuracy errors

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Sources of Noise

• Intrinsic Thermal noiseThermal noise1/F noise

• Externally induced • Externally induced RF Line frequencyLine frequency

• Noise “floor” of instrumentation

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Noise Induced Into Interconnects• Measurement setup

I t t Interconnect • another circuit element• Example : Twisted pair wiring

Environment• Line frequency fields generate Common

mode noise• Radiation from fluorescent lights

60 Hz to 100 MHz • Conductive coupling between noisy loads

and sensitive measurement instruments

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Noise ReductionNoise ReductionPre-acquisition

Setup pShielding, cabling, careful physical placement etcInstrument mode (Filtering, Integrating)

P t i iti Post-acquisition Filtering, Averaging

NOTE: Be careful with post-acquisition

Instrument performance may have been degraded enough that the data is “beyond repair”

•Input stage saturationInput stage saturation

•Noise is consuming dynamic range of the instrument

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Analog Input – Noise and Filteringg p gLowpassFilterFilter

Time Domain Time Domain

LowpassFilter

• Removes noise

Frequency Domain Frequency Domain

• Blocks unwanted frequencies• Prevents aliasing

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Best Practices for DAQ: Isolation• Two reasons for isolation:

El t i l I l tiElectrical IsolationSafety Isolation

Opto-isolator Transformer Capacitor

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Best Practices for DAQ: Isolation• Consider isolation for measurement systems that involve

any of the following:any of the following:Close vicinity to hazardous voltagesIndustrial environments with possibility of transient voltagesp y gEnvironments with common-mode voltage or fluctuating ground potentialsEl t i ll i i t h th ith i d t i l tElectrically noisy environments such as those with industrial motorsTransient-sensitive applications where it is imperative to prevent voltage spikes from being transmitted through the measurement g p g gsystem

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Common Mode Voltage Rejectiong j

What will a non-isolated DAQ board read?

DAQ BoardAI+

5 V

DAQ Board

5 V?+-

AI-GND

5 V Common Mode V lt

-

5 V Voltage

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Isolated boards will reject the common mode voltage and read 5 VWhat will a non isolated DAQ board read now?

Common Mode Voltage Rejection

AI+

DAQ BoardIsolated boards will reject the common mode voltage and read 5 VWhat will a non-isolated DAQ board read now?

AI+

AI-

5 V ?5 V Automotive measurements• 42 V and 12 V common

mode

+-

GND55 V Common Mode Voltage

Isolation mode

Battery stack testing• Small individual 1 V cells

≤ ±60 V

• Small individual 1 V cells

Signal + Common mode = ± 60 VDCSi l 10 V ( th i l t d b d)

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Signal = ± 10 V (same as the non-isolated board)

Analogue Output – Considerations• Accuracy: digital‐to‐analog converter (DAC) resolution

• Update Rate: settling time and waveform frequencyp g q y

• Range: fixed or adjustable output voltage/current

Channel 0 DAC Channel 0

DACChannel 1Channel 1

16 bi• 16‐bit• 100 kS/sec• ±10 VDC, 0–20 mA

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PC-Based Data Acquisition (DAQ)PC Based Data Acquisition (DAQ)Sample System Based on Plug-In Board

SoftwareDAQSignal ConditioningSignalTransducer

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g

Many Different Bus ChoicesMany Different Bus Choices

Fast Ethernet

PCI

Gigabit EthernetGigabit Ethernet

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Bus Support Takes Different Form FactorsBus Support Takes Different Form FactorsNational Instruments Data Acquisition Devices

PXI/PXI ExpressPCI PCI Express Wireless Sensor NetworksNetworks

Ethernet/Wi-Fi

USB USB w Chassis Ethernet w Chassis

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Loop Rate and Waveform Speed:Loop Rate and Waveform Speed:Latency and Bandwidth

Best for applications with large data sets

Best for applications with frequent reads/writes, like single-point updatesBest for applications with large data sets

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Dedicated Bandwidth Per Device Additi l Ad t f Hi h Ch l C tAdditional Advantage for High Channel CountApplies to PCIExpress and PXIExpress

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High Performance DAQ with PXI

Modular Instruments– DMMs, Switches, Oscilloscopes, High-speed digital, Power

supplies, RF– Measurements: DC to 6 GHz– Resolution: Up to 26 bits

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Modular Instruments -Filter Characterisation Demo

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Instrument Control with LabVIEW

h

Over 5,000 Instrument drivers online, from over 250 vendors

GPIB ‐ USB ‐ Ethernet

RS 232 ‐ RS 485 ‐ LXI

ni.com/idnet

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Scientific Imaging Approach

Lighting, Lens, Camera, HW, SW

Transducer Signal Conditioning A/D SWTransducer, Signal Conditioning, A/D, SW

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NI Frame Grabbers• PCI, PCIe, PXI and PXIe boards• Analog • Analog

Standard and non-standard

• Camera Link• Camera LinkBase, medium and full

IEEE 1394 control adaptors• IEEE 1394 control adaptorsIEEE 1394a and 1394b

Gi E Vi i i t f• GigE Vision interfacesOptimized for NI software

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NI Vision NI Vision Platform

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Image Acquisition Demo

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Signal Processing with LabVIEW

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The Role of Signal Processing, Analysis and MathAcquire Analyse Present

Signal Processing, Analysis and Math:Fundamental Components of

Virtual Instrumentation and Graphical System DesignVirtual Instrumentation and Graphical System Design

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Design Prototype Deploy

An Effective Platform for Signal Processing & Analysis: Signal Processing & Analysis

Choose an appropriate approach Reuse your existing code

Instrument your algorithms Prototype and deploy to

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y g yp p yembedded targets

UIUC Innovators develop Mind-Computer Interface with NI LabVIEW

Application: University of Illinois at Urbana-Champaign (UIUC) engineering students developed a device that translates thought i t h d f t l into speech or commands for control over wheelchairs and other devices. They used LabVIEW to develop the signal processing algorithms for translation algorithms and to i l t t t implement prototypes.

NI Products: Signal Processing in LabVIEW, USB DAQ

“Working with LabVIEW simplifies development and encourages innovation by offering

www.theaudeo.com

an intuitive graphical programming approach that allows you to focus on innovationrather than programming details.”

Michael Callahan, CEO, Ambient Corporation

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Interactive Math with the MathScript Window• Fully integrated into

LabVIEW Access from LabVIEW menu (Tools MathScript Window)

C d Li i t f• Command Line interfaceEnter .m file commands / scripts, see an immediate p ,responseOpen / run your .m file scriptsView textual output command View textual output, command history, variables, and plots

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Built-in Graphical Tools (VIs) for Signal Processing Analysis and Math (Abridged List)Processing, Analysis and Math (Abridged List)

• Signal Processing & Analysis • Mathematics– Waveform Generation– Waveform Conditioning– Waveform Monitoring

W f M t

– Numeric– Elementary and Special Functions– BLAS/LAPAC-based Linear Algebra

C Fitti– Waveform Measurements– Signal Generation– Signal Operations

Windows

– Curve Fitting– Interpolation / Extrapolation– Probability and Statistics

Optimization– Windows– Digital Filters– Spectral Analysis– Transforms

– Optimization– Ordinary Differential Equations– Geometry– PolynomialTransforms

– Point-by-PointPolynomial

– Formula Parsing– 1D & 2D Evaluation– Calculus

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– Zeros

LabVIEW Toolkits for Signal Processing and Analysis(Sound & Vibration)(Sound & Vibration)

Sound and Vibration Order Analysis

Distortion, Octave Analysis, Swept Sine, S&V Level, Frequency Measurements, Limit Testing, Transient Time-Domain Integration

Order Tracking, Order Extraction, Online Order Analysis, Order Spectrum Selection, Tachometer Signal Processing Waterfall Transient, Time Domain Integration,

Weighting, Waterfall Plot, …Signal Processing, Waterfall Displays, Orbit / Polar Plots, Bode Plots, …

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LabVIEW Add-On Toolkits for Signal Processing and Analysis(RF & Communications)( )

Modulation Spectral Measurements

Analog / Digital Modulation/Demodulation, Channel Models, Bit Generation, Bit Error Rate Channel Coding Modulation

Zoom FFT, Power-in-Band, Adjacent Channel Power, Tone Detection, …

Rate, Channel Coding, Modulation Measurements, AWGN, Phase Noise, Constellation Plots, Eye Diagrams, …

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LabVIEW Toolkits for Signal Processing and Analysis(Multi-Purpose)(Multi Purpose)

Advanced Signal Processing

Digital Filter Design

Wavelets FIR / IIR Filter Design / Analysis Wavelets,Time-Series Analysis (Independent Component Analysis, Principal Component Analysis, Model-Based Spectral Analysis )

FIR / IIR Filter Design / Analysis, Quantization, Fixed-point Modeling, Fixed-point Simulation, FPGA deployment,

Spectral Analysis,…),Time-Frequency Analysis (Gabor, STFT, …)

…

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Signal Processing Demog g

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Optical Coherence Tomography ResearchEarly Cancer Detection with LabVIEW & PXIEarly Cancer Detection with LabVIEW & PXI

Optical Coherence Tomography, or OCT, can provide sub-surface, cross-sectional images of opaque materials for visualization of tissues. For his next generation commercial system, Dr. Ohbayashi needs to perform 1 4 Million 1K FFTs every second for online analysis on the Ohbayashi needs to perform 1.4 Million 1K FFTs every second for online analysis on the acquired data.

Dr. Kohji Ohbayashi

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Kitasato University, Center for Fundamental Sciences

OCT Image Processing

Laser Line Digitize Restore Slice More

Yes

Scan Reflections

256 Channels

DigitizeReflections

256 Samples

Restore Slice with a 2D FFT

More Slices?

No256 Channels p

Per ChannelDisplay

3D OCT Scan

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National Instruments OCT Solution

256 ChannelsReflections 2D FFT

Scan Complete

Yes(Auto-detected)

Complete?

No256

LabVIEW

256 Samples

per Channel

~ 1.5 M FFTs / sec for Real-Time Performance

Iso-surfaceDisplay

56

Image Processing With LabVIEW

57

NI Vision PlatformVision Application

Configuration ProgrammingVi i D l t M d l g

- Vision Builder AI - -Vision Development Module -LabVIEW / LabVIEW RT

NI Vision Acquisition Software

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NI Vision Development Module• Programming libraries for

LabVIEW LabWindows/CVI LabVIEW, LabWindows/CVI, Microsoft Visual Studio

• Hundreds of image processing Hundreds of image processing and machine vision functions

• Includes Vision AssistantPrototypes and benchmarks your applicationGenerates code for LabVIEW Generates code for LabVIEW, Visual Basic, and C

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Image Processing Demog g

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Realtime Signal Processing, Analysis, and Mathematics

Code Reuse

M th ti

Simplified Interactivity Hybrid Graphical / Textual Programming

MathematicsNumericElementary and Special FunctionsBLAS/LAPAC-based Linear AlgebraCurve FittingInterpolation / ExtrapolationProbability and StatisticsOptimizationOrdinary Differential EquationsGeometryP l i l

Signal Processing & Analysis

Waveform GenerationWaveform Conditioning

Waveform MonitoringWaveform Measurements

Signal GenerationSi l O ti

Core 1

Core 2

IntuitiveHigh- / Low-Level

Extensive Built-in Signal Processing, Analysis,

PolynomialFormula Parsing1D & 2D EvaluationCalculusZeros

Signal OperationsWindows

Digital FiltersSpectral Analysis

TransformsPoint-by-Point

Tight HW IntegrationIntuitive Parallelism/Timing,Multicore Performance

61

Abstractiong g y

and MathMulticore Performance

Presenting Data With LabVIEW

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Express Visualization on 3D Models

• Import user‐defined 3D CAD models

• Map live measurements for advanced visualization

63

Data Visualisation and CommunicationData Visualisation and CommunicationVisualisation• Built in user interface objects

Reporting and Data Storage• File I/O functionality• Built‐in user interface objects

• Charting and graphing capabilities

• Remote application control

• File I/O functionality

• HTML reports for the Web

• Microsoft Word and Excel reports

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