Lab Introduction to LabVIEW: Spring 2015, Study notes of Physics

Download Lab Introduction to LabVIEW: Spring 2015 and more Study notes Physics in PDF only on Docsity! ESM3444 Laboratory 1 – Introduction to LabVIEW Spring 2015 Due at start of labs the week beginning February 02 1 OVERVIEW The goal of this week’s lab is to introduce you to LabVIEW, a powerful graphical programming environment that is particularly useful for automating data acquisition. LabVIEW stands for Laboratory Virtual Instrument Engineering Workbench, and programs written/created with LabVIEW are called VI’s (virtual instruments). It is a highly versatile program supported by Windows, Mac OS X, Linux, and a myriad of portable and handheld devices and is an industry-leading software tool for designing test, measurement, and control systems. Unlike in many computer programming languages that use text-based commands to carry out the programmer’s instructions, LabVIEW uses objects connected by “wires” to perform the requested tasks. Like any language, it will take time to become “fluent” and comfortable finding and using these objects to make the measurements you desire, but it is well worth the effort for anyone seeking a career as an engineer or scientist. There are many excellent books and online resources to help you become more comfortable. See for example, an online book available through the VA Tech library website called LabVIEW for Everyone (http://proquest.safaribooksonline.com/0131856723). For the time- strapped, a good single chapter summary can be found in chapter 5 from Measurement and Instrumentation – Theory and Application (http://app.knovel.com/web/toc.v/cid:kpMITA0001). By the end of the session you should be able to: • Use LabVIEW to create applications • Understand front panels, block diagrams, controls, indicators, and data types • Find and use built-in LabVIEW functions. • Create applications that use plug-in data acquisition (DAQ) devices EXERCISE 1 LabVIEW VI’s consist of a front panel, which serves as the user interface for a completed program, and a block diagram, the heart of the program where object blocks are wired together. In this exercise, you will familiarize yourself with these features by using LabVIEW to generate a signal and measure it using external data acquisition hardware. 1. Connect the NI-cDAQ-9174 chassis to your computer using the USB cable. 2. Open Measurement and Automation Explorer on the Desktop. 3. On the Configuration pane located on the left side of the window open My System>>Devices and Interfaces>>NI-cDAQ-9174. ESM3444 Laboratory 1 – Introduction to LabVIEW Spring 2015 Due at start of labs the week beginning February 02 2 4. In the center pane the devices that are recognized can be seen. Double-click on NI 9263: “cDAQ4Mod1” to open the device. 5. Run the self test located at the top of the center pane. This tests the device to make sure it is communicating properly. If your device fails the self test check to make sure that the card is seated properly in the NI-cDAQ-9174 chassis and the USB cable is connected properly. 6. Open the test panels. This window will give you control over the device without the need to open LabView. This is a good resource for troubleshooting your DAQ device. 7. Close the Measurement and Automation Explorer. 8. Open LabView. 9. Create a new .vi File>>New VI 10. Open the block diagram <ctrl+e> or Window>>Show Block Diagram. 11. Place a while loop onto the diagram Functions>>Express>>Execution Control>>While Loop 12. Place a Simulate Signal Express VI inside the while loop on the block diagram Functions>>Express>>Input>>Simulate Signal 13. Configure the Simultate Signal Express VI a. Under Timing set the Samples per second to 10000 and deselect Automatic beside number of samples then click OK 14. Place a DAQ Assistant Express VI inside the while loop on the block diagram Functions>>Express>>Input>>DAQ Assistant. Configure the DAQ Assistant: a. Choose Generate Signals>>Analog Output>>Voltage. b. Choose device cDAQ1Mod1 (NI 9263)>>ao0 to generate a signal on the NI-9263 analog output module and click Finish. c. In the DAQ Assistant window define the parameters of your analog output operation. Under timing choose “Continuous” for the generation mode. Leave all other fields as default and click OK. 15. Wire the output of the Simulate Signal Express VI to the input of the DAQ Assistant Express VI. 16. Create another DAQ Assistant Express VI to read in voltage and placed it on inside the while loop in the block diagram Functions>>Express>>Input>>DAQ Assistant. Configure the DAQ Assistant: a. Choose Acquire Signal>>Analog Input>>Voltage b. Choose device cDAQMod1 (NI 9201)>>ai0 to acquire a signal from the NI-9201 analog input module and click Finish. c. In the next window define the parameters of your analog input device operation. Under timing settings choose “Continuous” for the acquisition mode and set the Samples to Read to 1000. Leave all other choices set to their default values. Click Ok to exit the Wizard. 17. Open the Front Panel <ctrl+e> and place a graph on it Controls>>Express>>Graph Indicator>>Graph.