10-17-2007 05:34 AM
10-17-2007 02:52 PM
03-18-2008 04:18 AM - edited 03-18-2008 04:22 AM
03-19-2008 02:23 PM
rpursley8 explains how to calculate the beats per minute in the first page of this discussion forum. Here is what it says about how the EKG processor.vi calculates the BPM:
I have attached a VI that should do what you want if you have Labview 7.1 and Advanced Analysis Library.
If not, then this is what the VI does.
First you process the signal a little to enhance the R wave.
1. Take the derivative of the signal (difference function), name this signal X
2. Perform a Hilbert Transform of X to get Y
3. Combine to get Z = X + iY (complex) and take the magnitude of Z
4. This process will enhance the R wave amplitude in relation to the rest of the signal
Then you perform a peak detection to find all of the peaks and their locations.
Find the difference between the peaks to get the number of points between beats.
Divide this number by (Sampling Rate * 60) and invert the number to convert to beats/min.
The Advanced Analysis Library has the Derivative, Peak Detect, and Hilbert Transform functions used in the VI. I tried to save it as version 7.0 but it wouldn't let me.
If you have more specific questions about certain parts of the calculations, please let us know!
04-29-2008 12:28 AM
04-29-2008 12:48 AM
You can read the following app notes for more help on HRV detection and analysis.
06-22-2008 12:22 AM
I tried to compare the result of the beat per minute to constant number; To use the output and activate a case containing an alarm but since the output is array of Boolean there was an error in the wiring. Is there a way to compare the beat per minute and get a Boolean output?
I attached the VI
06-22-2008 12:30 PM - edited 06-22-2008 12:30 PM
I had provided an answer with image and code fix in your original post.
Please continue the discussion in the original thread and do not hijack other threads with a new topic.