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Hall effect sensor to RPM

November 13, 2016, 2:23 pm
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Hi everyone, I am having a great deal of difficulty designing the control system for my senior design project.

 

I integrated an Arduino Uno with Labview and I am currently attempting to use a "latching" hall effect sensor to output the RPM of a motor, once I am able to that I need to have the motor turn off once it reaches a desired RPM. The hall effect sensor output switches between 0V and 0.5V and if I understand correctly, I need to turn the analog signal into a square wave then output the highs and lows into 1's and 0's with respect to time/frequency. Then from there, I think I may have to use a timer to calculate for RPM? 

 

How would you guys go about doing this? I am doing all I can to research but making the block diagram is very difficult for me. Please help, I am very stressed.

 

Thanks in advance.

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Can I integrate a PLC/VFD to drive a large motor with Labview through Arduino?

November 13, 2016, 3:09 pm
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I was curious if it would be possible to use labview interfaced with an arduino Uno to control a large motor using a Programable Logic Controller (PLC) or a Variable Frequency Drive (VFD). I would like to set the frequency that the motor is to be ran at through labview then I would like to stop the motor when it reaches a certain frequency/RPM. I plan on implementing a hall effect sensor to determine the RPM of the motor. 

 

Would I have to use more than one Arduino in order to do this? I'm the electrical engineer in my senior design group. I understand that theoretically something like this should be possible, but I feel as if my programming and coding skills are not as great as my duty in this project may consist of (I am working on this). Any help at all is greatly appreciated.

 

Thanks!

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Programmatically changing device ID/name in VISA or IMAQdx session?

November 13, 2016, 4:28 pm
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I have an application where I have a camera (running through IMAQdx) and a motor running through serial communication (VISA).

 

My challenge is this: The solution is deployed across a number of computers and the camera and motor IDs may change from one computer to another. To deal with this, each computer has a unique config file that contains amongst other things the IDs of the devices attached to that computer.

 

Is there an easy way to read a text string and have that entered as the device ID handle in both VISA and IMAQdx sessions? (The solution may be different for the two.)

 

If I take a VISA reference, for example, I cannot find an option on the properties drop down menu to change the session identifier. I can read it, but I can't write to it. Any ideas?

 

 

 

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How to read multi frame CAN message with NI USB-8473

November 13, 2016, 4:49 pm
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using USB-8473 to test automotive electrical products: with commands to read serial number from UUT, the expect answer is 28 bytes serial number in format as below:

TX: 03 22 XX XX 00 00 00 00
RX: 10 21 62 XX XX 31 32 33
TX: 30 00 14 00 00 00 00 00
RX: 21 34 35 36 37 38 39 30
RX: 22 31 32 33 34 35 36 37
RX: 23 38 39 30 31 32 33 34
RX: 24 35 36 37 38 00 00 00

 

now the issue is, most of time I only received three frame as show in underline, but cannot received the last frame.

 

my question is the issue relate to CAN card USB-8473 or the LabVIEW code (show in below)?

 

Untitled.png

 

BTW, all the frame can read with NI PXI CAN card and CANoe device.

 

your help is well appreciated!

 

thanks!

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easy question about Combo box indicator

November 13, 2016, 6:15 pm
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Hi, I have a very simple question about the Combo box indicator.

when combo box get multiple lines and show multiple lines. i want it show the last line auto, no need scrool the bar.

how to make it happen?

Thanks!

Nemo

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time delay

November 13, 2016, 10:36 pm
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hello,

i'm doing a little project on fuel control system. I want to know how to add simple time delay in my input. the input is fast but the output in real life is slow. so i want to slow down the input with time delay or. how is it possible. its just like heating the water. you can open the stove gas fast but the water takes time to heat.

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Static IP adress for sbRIO

November 14, 2016, 12:12 am
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Hello,

 

I want to set the IP adress of my sbRIO-9607 to a certain value. The IP adress should be static. I tried to do this in a SubVI, there is a screenshot attached to this post. Whenever I try to run the VI, I get an error : 

Fehler -2147220609 bei nisyscfg.lvlibSmiley Frustratedave Changes (System).vi:1280001

NI System Configuration:  (Hex 0x8004037F) A property contained a value that is not valid or is out of range.

When I remove the 'IPAddrMode' from the property knode, I don´t get an error, but the IP-adress stays the same.

I would appreciate your help.

 

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Have I to install OPC in the target executable PC?

November 14, 2016, 1:26 am
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Hello everyone.

First of all thanks a lot for reading this post and being able to help.

 

I have a program which use communication with PLC throught NI OPC Server.It works fine in my development machine.Now I want to build an executable to run it into another PC target.Do I have to install OPC in PC target as well? or I don't need it?Thanks a lot.

 

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1D array into 2D array

November 14, 2016, 1:29 am
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Hi all,

I have a 1D array like this: (A,B,C,D,E) and I want to get an 2D array like this:

(A,B,C,D,E

A,B,C,D,E

A,B,C,D,E

.....

....)

Because there wiil be 512 rows in that 2D array, it is inconvinent to use Build Array function. Could someone help me? Thanks!

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write file measurement

November 14, 2016, 2:17 am
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Hello every one...iam facing a proble..i.e iam saving data using write to file measurement.in this iam connecting signal data and some caluculated data but it saving only time remaining things only saving in first row ofter rows nothing saving...so my need is to save all the reading continously until end of running aplication...

 Thankl you

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3D Intensity Map with interpolation

November 14, 2016, 2:44 am
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I would like to plot an intensity map similar to the one in the attached file except I only need the color pattern. The points in black are not necessary neither are the red rpm ranges.

A measurement is made for each point  in black and the color has to be interpolated between points.

The Intensity graph doesn't fit my need as the scales resolution required is not known and there is no interpolation being done between points.

Ideally I would need each point to be defined by a cluster of 3 elements ( X,Y,Z)

 

I haven't been able to find a 3D graph in labview going in the right direction for me.

 

Thank you in advance for you help.

 

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Analysis of paper questionnaires using NI Vision development module

November 14, 2016, 3:51 am
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Hello labviewers

 

I really need your support for the following subject.

I have to develop an application, which will automatically collect the answers from paper questionnaires that will be scanned and stored as images. I have attached a sample questionnaire, to give you an idea of what is required during the image analysis.

Till now, the only thing I have thought, is to use the golden template comparison vi and compare an empty questionnaire with a filled one and take the differences (that are the replies) an locate them using particle analysis. But I have encountered a lot of issues using this method, with the most important being, how to exactly align the two images , so that their differences are only the answers to the questions. Because the forms will be scanned, I cant use hardcopied values for the alignment because the source image could be rotated or shifted relatively to the template. The questionnaire has crosses at its corners to help to the alignment but I dont know how to position the images in order for the crosses to coincide.

 

Could you please give me an idea for the alignment of the two images or a suggestion for a different solution to the project?

 

Thanks a lot

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SQL CMD answer

November 14, 2016, 8:49 am
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Hi, I use Labview db toolkit, but don't show the query answer in front panel.

 

I use this query with "Execute Query VI" :

 

UPDATE dbo.trc_PCBA_Linky
SET WorkOrderName='Workorder',BoxID=123,Packing_Timestamp=GETDATE(),Packing_Result=1
where [Serial_PCBA]= 'ABCDEFG1234' AND [ICT_Result]=1 AND Packing_Result is null

if(@@ROWCOUNT=1)
PRINT 'Packed!'

 

I want to get back the query answer "Packed!" How can I get back the SQL PRINT answer? 

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TDMS logging from multiple loops

November 14, 2016, 9:04 am
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Hi All,

 

As part of thrust measurement system, I am have setup a VI to output PWM and log RPM, temperatures and power. I have grouped my read channels into different loops (mostly based on cards) and they output at rates from 10 Hz - 1 KHz. I am read trying to use TDMS advanced palletes to log this data together possibly in same .tdms file under different column headers but no success so far(as based on my reading so far it appears I need to use advanced TDMS than simple since I have mulpile data inputs). My questions are;

1. Can we use TDMS advanced  or standard version to log data from multiple loops ?

2. If so, whats the best way to setup this ? Do I setup "TDMS file open", "TDMS set file info" for each loop and first loop creates the file and rest just opens it OR should I just use this once and branch it to different loops ?

 

I had a success of logging 2-3 loops output to a single file with standard TDMS but when I added more loops it didn't work very well.  

 

I have attached a part of my VI where I am trying to get 2 loops to output the data to same file. 

 

PS: This is my first post, so please let me know if I can post additional info or use different board for this topic. 

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LabVIEW: Generic file I/O error - VIs missing when loading top-level VI.

November 14, 2016, 11:48 am
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I'm aware of some of the other threads with this same error dialogue, but I'm not sure the context is the same as mine.

 

I'm having a problem where a previously healthy library has now stopped loading correctly. 

 

When I try and load my top-level function, I get the 'Generic file I/O error.' (see attached image).  When I dig in, I find two sub-VIs, three layers down are missing sub-vis. This is strange because all relevant sub-VIs are stored in the same library. I cross-checked the paths for each sub-VI and they are all in the right place. 

 

If I manually 'replace' the missing sub-VI (question mark placeholder) with the appropriate sub-VI from the library, the application will function normally. I can save it, and everything seems to be fine. However if I close out LabVIEW and re-open the application, the same problems appear again. 

 

Very frustrating problem and I'm kind of losing my mind. 

 

I'm assuming the fix might be to copy/paste code into a new, fresh sub-VI with a new name and link to that instead, but I'd like to understand what happened.

 

Note: as far as I can tell I am not suffering from filename length issues - I'm storing locally and the filenames are short, without forbidden characters. I am using SVN Tortoise for backup. I'm not sure if that is relevant. I also migrated this application from 64-bit to 32-bit, although this error started appearing more recently than the migration.

 

 

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Is LabView the right tool to visualize Automotive CAN messages?

November 14, 2016, 12:20 pm
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Hello,

i'm absolutely new to LabVIEW and before digging into it, i'd like to know if it is the right tool for me.

I want to analyze CAN messages from automobiles, especially unknown messages to get their meaning. So visualizing and replaying data in realtime using graphs, gauges and bit-signals would be a great help.

 

The CAN messages comes in LAWICEL protocol, just simple TSV ASCII files.

 

Maybe there are some examples i should choose?

Any help would be greatly appreciated

 

can

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saving values in an array

November 14, 2016, 12:31 pm
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Hello,

 

In this program you have to calculate the gravity force, everytime you press 'calculate' the number had to be autoùmatically stored in an array. The array has to contain all previous values.

Can anyone help me please?

Regards

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Requesting single or multiple data from TCP server

November 14, 2016, 12:59 pm
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The TCP Server VI has many variable which need to be sended to the client. But not all of this data is needed on each request. Some variables are requested more frequently compared to others. It is unnecerssary to send the all the data all the time. What is an elegant way of implementing this where the client asks for one or a multiple combination of these datasets?

 

Cluster of 8 x UNIT8 - Fuse information - 1Hz

UINT8 - Voltage - 5Hz

Cluster of 8 UINT32 - Motor speed - 100Hz

UINT32 - Elevation - 200Hz

etc....

 

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Pane Size event

November 14, 2016, 1:56 pm
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I have noticed (what seems to be) different behavior for the Pane Size event between 2013 and 2016.

 

This is the behavior I am seeing with seperate vi's on seperate machines:  In 2016, the event happens while the user actively drags the window size larger or smaller.  In 2013, the event happens only when the user finishes dragging the window size.

 

My question is: is there a vi setting that I am missing to set the window resize behavior?

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Should This Generate an Error (Variant to Data)

November 14, 2016, 2:38 pm
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So I ran into a case I never thought I would but I have some code that is taking an empty variant, and turning it into...an empty variant using the variant to data.  To my surprise this generates error 1.

 

Example_VI_BD.png

 

Now the actual code has the Reply Data Type, as a type def template that a developer can then replace and the other places that the type def is used gets updated.  But if they choose not to update the type def then I anything would be wrong since it would be converting from one empty variant to another.  Is this expected?  The easy solution is to just check for an empty variant on the input, and if it is, then use a case structure with the default data of the Reply.

 

Edit: LabVIEW 2015 SP1 f3 32-bit, Windows 7 SP1 x64

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