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LVDT signal AC phase demodulation

I'm currently completing my final year project and I am using an LVDT. I need to take the output signal from it and demodulate it to give a linear output that intersects the origin (instead of the V output). As I am a bit of a novice with LabView, any help is appreciated!

 

Lewis.

 

P.S. I am using Labview 8.5.1

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Lewis,

 

What have you tried so far?  Do you have the data acquisition working? Do you have a mathematical formula which represents the phase demodulation?

 

The people who participate in this Forum will not do your projects for you, but we will answer specific questions.  Post what you have so far with some typical data saved as defaults and point out what works and what does not.  For the parts which do not work, indicate what the result is and what you expected.  Include any error codes or messages as they are often very useful.

 

Lynn 

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luigi64 wrote:

I'm currently completing my final year project and I am using an LVDT. I need to take the output signal from it and demodulate it to give a linear output that intersects the origin (instead of the V output). As I am a bit of a novice with LabView, any help is appreciated!

 

Lewis.

 

P.S. I am using Labview 8.5.1


 

This forum works this way. You present program design ideas. And we will discuss them with you, and help you on the way to a solution. But anyway here is a freebie http://www.cosmolearning.com/video-lectures/lvdt/


Besides which, my opinion is that Express VIs Carthage must be destroyed deleted
(Sorry no Labview "brag list" so far)
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Sorry, I was in a bit of rush when I posted my message. I was just using two simulated signals to crudely mimic the secondary coils of the LVDT first. But I am having difficulties in doing the phase demodulation of the signal. I don't really know what functions to use. After that, it is simply just a case of putting the signal through a low-pass filter.
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First you need to understand the mathematics of what you are trying to do.  Work through an example of multiplying two sine waves of the same frequency but with different phases (on paper).  Then try to implement that in LabVIEW code.  For simple applications with clean signals that may be good enough to produce some usable results.

 

When you have gotten that far, post your code along with the data you are using and ask questions about any problems you are still having.

 

Lynn 

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This is a basic synchronous demodulation setup.



Besides which, my opinion is that Express VIs Carthage must be destroyed deleted
(Sorry no Labview "brag list" so far)
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