Need Help w/Labview

I need urgent help on a program that I am suppossed to design using
labview(5.1), in conjuction with circuit boards designed by national
instruments. The program calls for controlling Eurotherm 818
temperature controller and National Instruments ER-8 relay control
board. Both controls use digital and analog I/O board designed by
national instruments. I appreciate all the help I can get.
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Check out the Functions>>Structures>>While Loop. You can set the
condition and wire it to the stop, or you can use a boolean switch.
Beware, though, if you use the latter, wire it to an inverter and then
to the stop.
Hope this helps.
Jon A. Rinkenberger
Atmospheric Physics Research Laboratory
Physical Science Department
Embry-Riddle Aeronautical University
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Similar Messages

Need help writing Labview Program!!!!!

I have a labview project that needs to be finished. I was not the original creator of the program and the guy who created no longer is involved with the project and I am left to finish it. Could you make the final adjustment so I can turn this into my professor and get the final grade. Thanks! Willing to pay! Negeotiable price!!!!!!!!

Need help completing assignment! Could anyone assist me in this project!
Attachments:
dial tone detection.zip ‏1253 KB

Need help using LabVIEW 7.1 and data socket to transfer images

I need help transferring images across a company network using: LV 7.1, IMAQ 3.0 and a PCI 1407 image aquisition card. I am trying to use datasocket to transfer video image across a company network. I have attached sample vis. Thanks in advance for your help.
I. Cyr
Attachments:
Vibration Chamber Vision_Cyr.llb ‏129 KB

Hello –
Something that you need to consider is the fact that when you are sending an image over Data Socket, it is not really the image what is being transferred but a pointer to the image. Please take a look into this Knowledgebase.
Also, you might find this Example Program useful.
Hope this helps.
S Vences
Applications Engineer
National Instruments

Need help with LabVIEW code for motor control.

Hi,
My name is Sasi. I am a BME grad student working on my thesis topic of evaluating spine implants for low back pain. For this I am building a test machine that would apply pure moments to a spine specimen. I am using LabVIEW 8.5 to implement control of a brushless AC servo motor. My requirement is,
Step 1: Initialize the motor.
Step 2: Start moving it at a uniform RPM to the right (This RPM value too user can enter).
Step
3: While doin Step 2; simultaneously read torque cell data (Using DAQ
asst.). DAQ o/p is from 0 V to 10 V; 0 V being -10 Nm n
10 V being +10 Nm
Step 4: When Torque value reaches +10 Nm, i.e 10 V, the motor stops.
Step
5: From the position where motor stopped (i.e no need to reset to
initial position) Start moving in the opposite direction at the same
uniform RPM as in Step 2 while reading torque cell data.
Step 6: Once again when torque reaches -10 Nm, i.e. 0 V, the motor should stop.
Step 7: Repeat 'Step 2' to 'Step 6' 3 times.
Step 8: Reset motor postion.
Till now I have managed to get the motor to move forward n backward @ a desired vel, accl, n deceleration for 3 cycles. I am attaching my code. I am having problem inserting the code for reading DAQmx amidst all this. Can anyone help me out.
Thnks,
Sasi.
Solved!
Go to Solution.
Attachments:
Test_012609.vi ‏35 KB

Hi Sasidhar,
I took a look at your problem and I think I have a workable solution for you. I definitely agree with Lynn's suggestion of using parallel loops. This will allow the DAQmx portion to run uninhibited by the motion portion, and vice versa. Plus, you only need to iterate the motion loop whenever the voltage level crosses a threshold. So, by iterating on the motion code in the same loop that you are iterating on DAQmx code, you are essentially wasting processor.
I created a VI that should do what you are wanting. I tested it out myself and it works great. You might have a tweak a few things to apply to your system (like motion board ID and DAQmx physical channel, etc.). I used two parallel loops and event-based programming. Basically the motion loop starts the motor spinning at the specified velocity. Once the motor is spinning, it waits for the DAQmx loop to tell it that the voltage value has crossed the threshold. When the voltage value exceeds the maximum threshold (which I set to a value slightly less than 10 to allow for jitter and saturation), the DAQmx loop signals the motion loop that it can finish its iteration. The motion loop stops the motion, reverses the direction, and starts the motion again. Once motion has started, it again waits for the DAQmx loop to tell it that a threshold has occurred, but this time, it is looking for a minimum threshold. I used "Occurrences" to implement the event-based programming in LabVIEW.
I have commented the code rather thouroughly, so hopefully the comments will answer any remaining questions. The benefit of using event-based programming for this is that you save processor time, and your motion is more closely synchonized with the DAQmx. Instead of iterating the motion loop as fast as you can, checking for updates each time, you just pause it, and wait for the other loop to tell you when to start up again. In the mean time, the processor doesn't have to worry about iterating that loop over and over again. Also, when the occurrence does occur, you catch it immediately, instead of having to wait until the next iteration. Thus, you are more closely synchronized with the DAQmx portion of the code.
I hope this will help you. Please post back if you have any questions about the code or its implementation. Good Luck!
Message Edited by Wes P on 02-03-2009 05:18 PM
Wes P
Certified LabVIEW Developer
Attachments:
Motion and DAQ.vi ‏59 KB
DAQmx Loop.png ‏24 KB
Motion Loop.png ‏17 KB

Need help with Labview code for DAQmx

I'm currently trying to write Labview code for some thesis research and am having problems. I'm using the cDAQ 9172 with strain gage modules and two voltage input modules. I'll be reading/recording a voltage from an external source on one channel, while recording strains and accelerations with the other channels. I need to do all this simultaneously.
Everything I've done to this point has been in SignalExpress so I'm not sure how to program any of this. I also need to be able to calibrate the strain gages prior to each set of recordings. Any help you guys could offer would be greatly appreciated. Thanks.

Hi,
I'm not sure how much this will help you, but I've attached a screen dump of code from a project I did that sounds pretty similar to what you're working on. The code is from a subVI that I used to create the daqMX measurement task for my data acquisition. I was also using a 9172. This was written in 8.5, but the only thing that you may not have access to is the functions for null offset and shunt cal of the strain gage channels. Hopefully this will at least get you started on your way to setting this up.
Andrew Carollo
Attachments:
create task.jpg ‏208 KB

Need help reg labview control *.ctl

What are the uses of creating labview controls i.e. *.ctl and how to do this?
thanks in advance.

The simple answer as ssk pointed out is that it will save you lots of time using a custom control because when you need to modify it, you only need to change the master.
To create one, simpy select under the Files menu, New, and browse to the bottom to select Custom Control. See attached image.
FILES>NEW>Custom Control
Message Edited by JoeLabView on 10-03-2007 08:01 AM
Attachments:
customCtrl.PNG ‏40 KB

Need help writing host program using LabView.

Need help writing host program using LabView.
Hello,
I'm designing a HID device, and I want to write a host program using National Instrument's LabView. NI doesn't have any software support for USB, so I'm trying to write a few C dll files and link them to Call Library Functions. NI has some documentation on how to do this, but it's not exactly easy reading.
I've written a few C console programs (running Win 2K) using the PC host software example for a HID device from John Hyde's book "USB by design", and they run ok. From Hyde's example program, I've written a few functions that use a few API functions each. This makes the main program more streamlined. The functions are; GetHIDPath, OpenHID, GetHIDInfo, Writ
eHID, ReadHIC, and CloseHID. As I mentioned, my main program runs well with these functions.
My strategy is to make dll files from these functions and load them into LabView Call Library Functions. However, I'm having a number of subtle problems in trying to do this. The big problem I'm having now are build errors when I try to build to a dll.
I'm writing this post for a few reasons. First, I'm wondering if there are any LabView programmers who have already written USB HID host programs, and if they could give me some advice. Or, I would be grateful if a LabView or Visual C programmer could help me work out the programming problems that I'm having with my current program. If I get this LabView program working I would be happy to share it. I'm also wondering if there might already be any USB IHD LabView that I could download.
Any help would be appreciated.
Regards, George
George Dorian
Sutter Instruments
51 Digital DR.
Novato, CA 94949
USA
[email protected]
m
(415) 883-0128
FAX (415) 883-0572

George may not answer you. He hasn't been online here for almost eight years.
Jim
You're entirely bonkers. But I'll tell you a secret. All the best people are. ~ Alice

Hi!! I need help: I'd like to know how to obtain a communicaion between a PLC of ABB model 07 KT 97 and Labview 8.

Hi!! I need help: I'd like to know how to obtain a communicaion between a PLC of ABB model 07 KT 97 and Labview 8.I have to realize a scada system to control an electrical implant.I think that I need to learn more about OPC server: do you have some manual and tutorial to help me step by step in this configuration?And do you have some examples (one time PLC is connected and well configurated) to realize communication with Labview software?
thank you so much!!
please!!!Answer soon because I need help!!!

Hi Leoeffe,
I've found some documents that cam help you to understand how is possible to communicate
unsing OPC Servers and ho use them in Labview 8.
First of all I suggest to take a look to these documents:
How Do I Use OPC in LabVIEW?
http://digital.ni.com/public.nsf/websearch/EA15F53DB6FECCA5862567240064DF09?OpenDocument
Connecting LabVIEW to an OPC Server through a DataSocket Connection
http://zone.ni.com/devzone/conceptd.nsf/webmain/DF8C0A4BA2E2B22A86256A3700592BEA
Using the LabVIEW Shared Variable
http://zone.ni.com/devzone/conceptd.nsf/webmain/5b4c3cc1b2ad10ba862570f2007569ef
You can also use the Labview DSC module:
Developing Monitoring Applications with the LabVIEW DSC Module for Control Systems
http://zone.ni.com/devzone/conceptd.nsf/webmain/199c3fb9456a16d986256b5200678917
LabVIEW 8 DSC Simplifies Distributed Development
http://zone.ni.com/devzone/conceptd.nsf/webmain/d76c3788a0c4c5668625708b0072987c
Tools for Troubleshooting OPC Interface Problems
http://zone.ni.com/devzone/conceptd.nsf/webmain/401CB3A4E216356286256BC7004B5831
I hope all these tutorials can help you.
Best regards,
MarcoL

Need help loading DLL in labVIEW project

I have a DLL that was written in C# that I want to load it to my labVIEW project. I have never done this before, so I need help. I chose Connectivity-Call Library Function Node then loaded my DLL. After, under function name, I typed in the function name from the code. I don't know what to do with other like Parameters.
They don't let me attach dll file
Can someone explain how to set the parameters and etc?

Well, it seems that you really need to learn quite a bit about .NET (ActiveX is very similar!) first.
The constructor node in your code creates an object in your .NET CLR (Common Language Runtime). This object exposes properties and/or methods. Use Property Node(s) and Invoke Node(s) to access these. Usually, you get references to other objects which you can work this.
Remember the golden rule for ActiveX and .NET:
Close all references you created in your LabVIEW code on your own (using Close Reference)!
Norbert
CEO: What exactly is stopping us from doing this?
Expert: Geometry
Marketing Manager: Just ignore it.

I need help regarding measurement of "time domain parameters of Heart rate variability" using labview.

I need help regarding measurement of "time domain parameters of Heart rate variability" using labview.
I am using Labview 8 ... I need to develop a software to accquire the ECG data (simulated enironment ) and compute the time domain parameters of Heart rate variability like "SDNN, SDANN...etc". Can some 1 plllzzzz help me out.Plzz help me if u can.Thanx in advance.

Hi Andy,
Thanx for responding. The input is from a text file. SDNN, SDANN,etc are the timedomain parameters of heart rate variability.
SDNN: the standard deviation of the NN or RR interval i.e. the square root of variance.
SDANN:the standard deviation of the averageNN interval calculated over short periods, usually 5 min,which is an estimate of the changes in heart rate due tocycles longer than 5 min
SDNN index, the meanof the 5-min standard deviation of the NN intervalcalculated over 24 h,
RMSSD: the square root ofthe mean squared differences of successive NN intervals
NN50: the number of interval differences of successiveNN intervals greater than 50 ms, and
pNN50 the proportionderived by dividing NN50 by the total numberof NN intervals.
The problem is dat I am a fresher to the world of Labview. I have jus recently started working on it. Can u please suggest me some some idea as soon as possible.
As i said I have the ECG data in the form of text files..I need to create sort of GUI to calculate the time domain parmeters....I need help urgently. Plzzz help me if u can. If u have and .vi example to calculate the RR interval plzz send it to me ASAP.
Thanku

Really need help (motor control using labview)

hi all readers,
im new beginner. really need help for my project. i've been assigned to monitor/control motor using labview 8.5 (using NI DAQmx). the problem is, the techinician told me that i cant use 3phase motor with this card. things that i need to displayed using labview is :
torque
power
current
voltage
speed
really appreciated if readers can help me with this:
wut type of motor shud i use that compatible with NI DAQmx
thanks a lot.

Hi fauziana,
NI data acquisition devices are primarily designed to take measurements, so it's a good idea to measure the signals that you have mentioned with a DAQ device.
You also can use DAQ devices for control tasks, but for reliable and deterministic control behavioryou typically need to use a real-time operating system (not Windows!). If you want to learn more about the pros and cons of using DAQ devices for motion control tasks, please refer to these threads. Still for standard motion control tasks it's much more efficient in terms of development time, to use a dedicated motion control device for the motion control part of your application.
In general the control part is independant from the motor type, as these devices only generate control signals (+/- 10 V). There are many power drives available, that accept this type of control signal and you should select your motor according to the requirements of your application.
For a more detailed system consulting, please contact your local NI branch. To select the products that fit best to your application requirements a face to face discussion is much more efficient than a discussion forum thread, because there are a lot of parameters that need to be taken into consideration. If you tell me in which country you are living, I can provide appropriate contact data to you.
Thanks and kind regards,
Jochen Klier
National Instruments

Error 1057 URGENT Need Help

Hi my friends and Labview Application Engineers,
I need help urgently.
I need to map my table control into a multicolumn listbox.
However, I get Error 1057 as shown in attached photo.
How should I get rid of the error? Thank you very much!
Attachments:
Error Msg.jpg ‏84 KB

-You want to get more views??? I think if your post is important and valid automatically many will view the post and try to help. But if you simply post the same thing 2 times doesn't mean you get more views.
-Coming to solve problem can elaborate your problem little more and post your vi if possible in LV12.
Thanks
Thanks
uday,
Please Mark the solution as accepted if your problem is solved and help author by clicking on kudoes
Certified LabVIEW Associate Developer (CLAD) Using LV13

Need help - I2C write/read with TAOS TCS3414 light sensor using USB-8451

Hello, I'm new to labview and need help setting up a vi that will allow me to communicate with a digital light sensor (TAOS TCS3414) using a USB-8451. I need to use the sensor to measure light from a light source that I designed and built as part of a project im working on. I've tried looking at several labview I2C exampled but find them to be very confusing. I've used an arduino to interface with the sensor successfully but need to use labview and dont understand how to write the program. The actions are simple; I need initialize the sensor with a simple command and then request data from 8 data registers and then read that data. The data will then be used in further calculations. The portion i need help with is writing and reading from the sensor. I've attached the datasheet for the sensor as a guide. I can also provide the arduino code that i use to read data from the sensor if that would help.
Pleae keep in mind that i am completely new to labVIEW. I really do want to learn from this but need quick results so the more help the better. It would greately appreciate any help or explaination.
Attachments:
TCS3414_Datasheet_EN_v1.pdf ‏1806 KB

Hi Aaron,
Here you go, this is made with a USB-8452.
When you run the code tick the power en dac enable box on.
Maybe you can help me with my problem, I want to use a fiber to sense light from a led.
Do you use any fiber hardware with the TCS3414?
gr,
Attachments:
TCS3414.vi ‏63 KB

Need help on how a user can control a video clip using their mouse

I need help. I've got a video clip of a rotating 3D
object(left to right) and i would like the user to be able to
control the rotation of the object using their mouse. I've looked
everywhere and i'm at a lost. Can anyone help me
Here is a link to what i'm trying to achieve:
http://www.sun.com/servers/blades/6000/gallery/index.xml?p=1&s=2
I know they use Java but i'm sure this can be done in Flash.
Thanks
Ray

Just use the plain linear fit!
(If you are discussing something you found in the forum, you should always include a link so we can see what you area talking about. What you probably found was a workaround that forces an intercept of zero for a special scenario. If you want to use general linear fit anyway, your matrix simply also needs a constant term)
If you still have problems, show us your code and some data.
LabVIEW Champion . Do more with less code and in less time .

Need help about Hidden Markov Model model

I want to make classification for EEG signal using Hidden Markov Model
algorithm based on neural network.
plz need help about how to implement this algorithm using LABVIEW.
if not I want another thing to make classification.
any one know information about this topic, send me a reply
thanks

Have you derrived the HMM that you want to implement?
If so, post the algorithm and we can provide comments on how to implement it using LabVIEW.
Message Edited by Ray.R on 04-12-2010 12:54 PM

Need Help w/Labview

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