Introduction to LabVIEW 8.5

• Original slides prepared by Prof. Xiaobin Le of Mechanical Engineering program

• Adapted for Electrical Mechanical Engineering program by Cap’n Tim Johnson, PE

Introduction to LabVIEW

Introduction to LabVIEW (1)

• What is LabVIEW?– LabVIEW– The Virtual Instrumentation (VI) Approach for

measurement systems

• LabVIEW environment – Three parts of a VI– Three palettes – Show context help– Status bar

What is LabVIEW?• LabVIEW - Laboratory Virtual Instrument

Engineering Workbench

• LabVIEW is a software, which uses graphical programming language for data acquisition, data analysis, presentation of result and instrument control.

• LabVIEW program is called virtual instrument (VI), because their appearance and operation imitate physical instruments, such as oscilloscopes and multimeters

The VI approach for measurement systems

High-SpeedDigitizers

High-ResolutionDigitizers and DMMs

Multifunction Data Acquisition

DynamicSignal Acquisition

Digital I/OInstrumentControl

Counter/Timers

MachineVision

Motion Control

Distributed I/O andEmbedded Control

Laptop PC PDADesktop PCPXI Modular Instrumentation

Signal Conditioningand Switching

Unit Under Test

LabVIEW +Computer

Hardware + sensor

Object being tested

LabVIEW environment

• Three parts of a VI– Front panel – Block diagram– Icon and connector

pane• Three palettes

– Tools palette– The Controls palette– The Functions palette

• Show context Help• Status bar

• LabVIEW provides an easy-to-use graphical programming environment, including all of the tools necessary for data acquisition (DAQ), data analysis and presentation of results.

• LabVIEW tries to make your life as hassle-free as possible. It has extensive libraries of functions and subroutines to help you with most programming tasks.

Three parts of a VI

A VI contains the following three components:– Front panel—Serves as the user interface for input

and show results for output and presentation.

– Block diagram—Contains the graphical source code that defines the functionality of the VI. (It is a executable program.). It is similar to circuits

– Icon and connector pane—Identifies the VI so that you can use the VI in another VI. Actually every graphic icon is a kind of sub-VI. It can execute a simple or complicated task and with input and output terminals.

• The front panel is the user interface of the VI. – A front panel contains controls for input and

indicators for output or data presentation• Controls are knobs, pushbuttons, dials, and

other input devices. – Controls simulate instrument input devices and

supply data to the block diagram of the VI.• Indicators are graphs, LEDs, and other displays.

– Indicators simulate instrument output devices and display data the block diagram acquires or generates.

Front Panel

A VI’s Front Panel

Front Panel Toolbar

GraphLegend

BooleanControl

WaveformGraph

Icon

PlotLegend

ScaleLegend

Front Panel• Controls = Inputs• Indicators = Outputs

Block diagram– A virtual circuit in which virtual components

are wired together– A executable graphical program– Accompanying “program” for front panel

A VI’s Block Diagram

Wire Data

GraphTerminal

SubVI

While LoopStructure

Block Diagram Toolbar Divide

Function

Numeric Constant

Timing Function

Boolean Control Terminal

Icon and connector pane – Icon and connector pane—Identifies the VI

so that you can use the VI in another VI. A VI within another VI is called a sub-VI.

– Provide the connectors for wiring

Three LabVIEW Palettes• The Tools palette is available on the front

panel and the block diagram.– A tool is a special operating mode of the

mouse cursor.• The Controls palette is available only on the

front panel. – The Controls palette contains the controls

and indicators you use to create the front panel.

• The Functions palette is available only on the block diagram. – The Functions palette contains the VIs and

functions you use to build the block diagram.

Tools Palette

Operating Tool

Positioning/Resizing Tool

Labeling Tool

Wiring Tool

Shortcut Menu Tool

• Floating Palette• Used to operate and modify front panel and

block diagram objects.

Scrolling Tool

Breakpoint Tool

Probe Tool

Color Copy Tool

Coloring Tool

Automatic Selection Tool

•The Tools palette is available on the front panel and the block diagram.

•A tool is a special operating mode of the mouse cursor.•Select View»Show Tools Palette to display the Tools palette.

The Controls palette• Select View»Show Controls Palette or right-click the

front panel workspace to display the Controls palette

• In the front panel mode, right click any empty place, the “control palette” will be shown. After you choose proper screen, you can pin that screen.

Functions Palette•Select View»Show Functions Palette or right-click the block diagram workspace to display the Functions palette.

•In the Block diagram mode, right click any empty place, the “function palette” will be shown. After you choose proper screen, you can pin that screen.

Show context Help When you point at any icon (graphical code), the description of the icon will be shown if the “show context help” is checked.

Run Button

Continuous Run Button

Abort Execution

Execution Highlighting Button

Additional Buttons on the Diagram Toolbar

Status Toolbar

Retain Wire Values Button

Step Function Buttons

End of Overview

• The next few slides will help you get started making your own virtual instrument.

Open LabVIEW

Lab #1 instructions

• Read Ch1 in “Getting Started with LabVIEW. • If your instructor hands out the pages for this chapter you won’t

need to open up the manual (instructions follow)• This manual is found (on my machine) at C:\Program Files\National

Instruments\LabVIEW 8.2\manuals or 2 selections down from where you clicked to start LabView.

• Click on LV_Getting_Started.pdf to open the manual.• Do NOT print out the manual!!!!• If you are working as a team have one of your team mates open up

the PDF and use that as your copy. • You can also as a supplement use two video tutorials found in the

Start menu called: to to enhance your understanding.

Tutorial

• As you read through the chapter make the VI and modifications suggested.

• Design a cover page for this lab that includes your name, course, Lab # and name, date, and a brief abstract.

• Turn in a screen print of the design’s front panel and block diagram.

• Answer the questions on the following page.

Begin designing

• You are on your way.• This lab is part of the design process steps

Gathering Information and Conceptualizing Alternate Solutions.

• The questions you are answering are:

What role will this software fulfill in a system?

What does using this software add to a system?

Homework Assignment #1

• Before the class meets again for lab…• Read Ch2 in “Getting Started with

LabVIEW”. Follow along in their tutorial and make the design suggested in the chapter.

• Submit a copy of the design including the Front Panel and the Block Diagram.

• Include a write up about how the design works and what problems it can solve.