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We appreciate your patience as we improve our online experience.
01-02-2018 12:04 AM
Hi all,
I am acquiring the vibration signal from the stored data in the form of TDMS format
I am designing an application based on vibration data by applying the signal processing techniques like FFT. In this application i don't want to use any DAQ system or DAQ max system. Just by using the file path i want design an VI
I am facing few problems as described below:
What actually i need is
Any suggestions how to go about this
Regards
Sowjanya
Solved! Go to Solution.
01-02-2018 12:23 PM
Hi Sowjana,
when I answered your personal message I suggested to create your own thread in this board instead of highjacking an old one…
1. There is a lot "interesting" code in your VI:
- why do you mix TDMS functions with ReadSpreadsheetFile function?
- why do you use GPIB-Clear with the path of your file as input?
- why do you initialize the queue as "waveform data", but write a plain 1D array into the queue?
- which delay do you see? Can you define "after sometime"?
2. When the data is delayed in the producer loop, then the consumer loop will lag too…
3. because you are filling the queue much faster than you can process the queue elements!
4. Simple solution: don't fill up the memory so fast! Limit the queue length to reasonable sizes as a quick (and dirty) solution…
5. See my question for point 1…
01-03-2018 12:27 AM
Hi all,
I want to develop an application based on vibration data by using FFT. In this application i am reading the vibration data in TDMS format , here the file size is approximately 414MB, To this TDMS file i want apply arrays and FFT technique ,because from this application i want to calculate the following points as described below
In my application i don' t want to use any hardware equipments , just by using basic labview toolkit i want to develop an application
Is it possible to develop an application like this, if possible how can i go about this
Any Suggestion
Regards
Sowjanya
01-03-2018 01:28 AM
01-03-2018 02:18 AM - edited 01-03-2018 02:23 AM
hi all,
i am not hijacking any thread. Just few hours ago whatever post i posted on discussion form is my project. may be my project is similar to old thread . As i am new to labview i dont know how to build an application based on vibration data
for that i need some help to start my application. yes i referred to some old threads because to see how they implement the vibration data to various techniques
By seeing that application i got some idea about implementation of data . for further process i am asking help in discussion forum
If any one hurts i am sorry
01-03-2018 02:32 AM - edited 01-03-2018 02:50 AM
Hi Sowjanya,
i want to calculate the following points as described below
1. calulating the frequency response for the vibration data, here vibration data is x- axis is time and y- axis is acceleration this should be represent in frequency response as frequency vs amplitude
2. plotting the total channel response and plotting the individual channel data , when i select a particular channel it should show the plot according to channel selection and it should also displays the values of the channel. For example like TDMS file viewer we select a channel data it displays the data according to channel selection. similarly i want to plot channel data like that
So you already know what you want - that's good!
All you need to do is to program all your requirements… 😄
You need to learn:
- how to read a TDMS file and parse it's meta data (like channel names)
- how to create a selection list from the channel names you read from your TDMS file
- how read the data from your file according to the selection in this channel list
- how to apply FFT on it
- how to plot the FFT results
For all those steps you will find example VIs in the example finder in LabVIEW.
And I recommend to do all those steps one by one to learn and understand them before putting all of them into your final VI(s)!
01-08-2018 04:03 AM
when i tried to plot the multiple channel data by using array it showing not enough memory to complete this operation
How can i go about this ?
Any suggestions
01-08-2018 04:13 AM - edited 01-08-2018 04:14 AM
Hi Sowjana,
again I moved your message from an old thread into your own one…
when i tried to plot the multiple channel data by using array it showing not enough memory to complete this operation How can i go about this ?
When you get "out of memory" then the waveforms are too big. What is the size of your TDMS file? How many samples do those waveforms contain?
Solution: read only parts of the whole waveforms to plot them…