Quantcast
Channel: LabVIEW topics
Viewing all articles
Browse latest Browse all 66732

closed-loop control using LabVIEW Real-time

$
0
0

Hi,

 

I am trying to use the LabVIEW Real-time module to control the vibrations of a flexible link. The highest frequency I am dealing with is around 1000 Hz. Considering that, I have a few questions:

 

1) I am using the 1 KHz clock with a period of 1 ms for the timed-loop, namely, I am capturing data at 1 KHz. I read in NI forums that there are limitations on the determinisim of the timed-loop if the MHz clock is used with loop rates of less than 1 msec, for Windows host PCs, even if the target isoperating under RTOS. Given data acquisition rate should be at least twice as fast as the highest frequency, I was wondering if I would run into problems using the 1 msec period with 1 KHz clock?

 

If yes, what if I increase the samples per channel of the DAQmx Read VI from 1 to 10 or something? Does that really increase my sampling rate?

 

2) Also, I realized that after runnig my real-time project for a certain time duration (e.g. 20 sec), I am not getting enough samples that I expect (assuming a sampling rate of 1000 Hz for the DAQmx Timing VI and 20 sec of runnig the code, I expect to see 20,000 samples). It seems to be that some data is lost either due to non-optimized parameters of the time-loop or due to the network stream parameters (e.g. buffer sizes that transfer the aquisition files to host PC).

 

 

Any idea would be greatly appreciated.    


Viewing all articles
Browse latest Browse all 66732

Trending Articles



<script src="https://jsc.adskeeper.com/r/s/rssing.com.1596347.js" async> </script>