LabVIEW Introduction Alan Jennings

Programming in general The Data: MATLAB, C, Java Variables, stack LabVIEW, Simulink, FPGA Connections (wires) 1 Output, Many inputs Excel Predefined by cells 3/28/2012 Programming comparison

Programming in general The Instructions: Inputs and outputs MATLAB, C, Java, Excel function, operator, method [m,b]= linearfit(x, 3*x+4) LabVIEW, Simulink, FPGA Blocks with inputs and outputs 3/28/2012 Programming comparison

Programming in general Structure: Order of execution MATLAB, C, Java, Excel Sequential: Line after line Routing commands Loops, conditional, break, goto, LabVIEW, As data is available Loops Simulink, FPGA Blocks with inputs and outputs FPGA physically simultaneous Simulink numerically simultaneous 3/28/2012 Programming comparison

Setting up a LabVIEW Program Front Panel Controls: how the user controls the program Indicators: Displaying results Function Wiring for using your VI’s by other VI’s Block Diagram Data: All controls and indicators, Also constants Doing something: Add functions Control what happens: Add structure 3/28/2012 LabVIEW Components

Front Panel Inputs: Number, Array, Matrix File names, Categories 3/28/2012 LabVIEW Components

Front Panel Inputs: Binary More Numeric 3/28/2012 LabVIEW Components

Function Blocks Icons Blocks Default values Using Context help Icons: little to no description Function Blocks Icons Blocks Default values Using Context help Hover over icons, blocks or wires to see what it is and the different signals Blocks expand to show all possible signals 3/28/2012 LabVIEW Components

Loops For Loop While Loop Sequence loops Case loops Indexing over arrays While Loop Wait for an event to stop (such as user or trigger) Feedback block Sequence loops Specify execution order Important for local variables Case loops Conditional Execution 3/28/2012 LabVIEW Components

Data Types Waveforms Arrays (column) 2d Arrays Values, to, Sample frequency Arrays (column) 2d Arrays Clusters (similar to structures) Objects (typical for controlling DAQ’s, etc) Easiest thing to do is use the port and create constant to see 3/28/2012 LabVIEW Components

Ex: Finding Largest Value Generate Data Compare each value to current best 3/28/2012 Programming Examples

Ex: Finding Largest Value Generate Data Use Gaussian generation block Set standard deviation and number of samples Convert data type Compare each value to current best Initialize the current largest value Use `for’ loop to index over signal Change selection based on logic test 3/28/2012 Programming Examples

Ex: Finding Largest Value Generate Data Set standard deviation and number of samples Use Gaussian generation block Convert data type Compare each value to current best Initialize the current largest value Use `for’ loop to index over signal Change selection based on logic test Ex: Finding Largest Value 1 5 2 3 4 6 4 3 3/28/2012 Programming Examples

Ex: Finding Largest Value Generate Data Set standard deviation and number of samples Use Gaussian generation block Convert data type Compare each value to current best Initialize the current largest value Use `for’ loop to index over signal Change selection based on logic test Ex: Finding Largest Value These are controlled by the front panel 3/28/2012 Programming Examples

Ex: Finding Largest Value Generate Data Set standard deviation and number of samples Use Gaussian generation block Convert data type Compare each value to current best Initialize the current largest value Use `for’ loop to index over signal Change selection based on logic test Ex: Finding Largest Value 3/28/2012 Programming Examples

Ex: Finding Largest Value Generate Data Set standard deviation and number of samples Use Gaussian generation block Convert data type Compare each value to current best Initialize the current largest value Use `for’ loop to index over signal Change selection based on logic test Ex: Finding Largest Value To pull of individual values, convert to an array Other blocks may require other formats 3/28/2012 Programming Examples

Ex: Finding Largest Value Generate Data Set standard deviation and number of samples Use Gaussian generation block Convert data type Compare each value to current best Initialize the current largest value Use `for’ loop to index over signal Change selection based on logic test Ex: Finding Largest Value Pull the 0 index as the initial condition Use it to initialize feedback block 3/28/2012 Programming Examples

Ex: Finding Largest Value Generate Data Set standard deviation and number of samples Use Gaussian generation block Convert data type Compare each value to current best Initialize the current largest value Use `for’ loop to index over signal Change selection based on logic test Ex: Finding Largest Value Indexed (pulls each value) Non-Indexed (returns last) Non-Indexed 3/28/2012 Programming Examples

Ex: Finding Largest Value Generate Data Set standard deviation and number of samples Use Gaussian generation block Convert data type Compare each value to current best Initialize the current largest value Use `for’ loop to index over signal Change selection based on logic test Ex: Finding Largest Value Flow if current largest is largest Flow if current value is largest 3/28/2012 Programming Examples

Ex: Approximating Human Control Dynamic System Generate disturbance, Or possibly tracking path Find the command as function of error and its derivative Do linear fit to find average gain values Find how well the gains describe behavior 3/28/2012 Programming Examples

Ex: Approximating Human Control TankControl.vi Simple Tank Control (loss proportion to height) 3/28/2012 Programming Examples

Ex: Approximating Human Control TankControl_2.vi Include maximum time Do linear estimation of control policy Use local variables 3/28/2012 Programming Examples

Ex: Approximating Human Control Doesn’t Work! Zeros for linear fit first time Troubleshooting planar fit error 3/28/2012 Programming Examples

Ex: Approximating Human Control TankControl_3.vi Add 2D and 3D graphs Add control for set point Add start button 3/28/2012 Programming Examples

I didn’t say the graphs looked good.

Sequence loop separates activation

Data Type conversions to use graphics Need to separate the array and bundle x & y as pairs

Other Program Challenges Programming Problems: Finding prime numbers Binary to dec converter tausiq.wordpress.com/2009/07/27/push-ups-with-blaze/ Rock, paper, scissor tournament Currency Converter Verifying 8 Queens 3/28/2012 Programming comparison