Averaging LVDT Signals

[JayBeau]

I am attempting to use Labview and a usb6210 DAQ unit to acquire and process voltage readings from two DC lvdt's.  The lvdt's will be used to measure strain resulting when a vertically oriented piston is driven into a sample.  I've used a bearing assemble to reduce wobble, but would also like to use the two lvdt's to elimate any remaining noise.

Being new to Labview I have as of yet only managed to acquire and process voltage readings from one of the two lvdt's.  I have found the best result by using a RSE setup, but would like to improve this by plotting and logging the average of every 100 samples.

Any help would be appreciated.

Jay

[jyang72211]

On your DAQmx red function, have you tried to use the Analog 1D DBL 1Chan NSamp option?  If you do so, you will get an array, with sampling rate that you set up with the timing node.  Then you read the array and average it inside a loop.  The loop would produce an average of the array on each iteration.

[mikealder]

I usually record at a much higher rate than required then average the data during post processing when using LVDTs rather than trying to do this in real time, this also gives you a chance to remove the unrequired data from the start and finish of the trace - Mike

[mikealder]

Data is stored in csv format (coma delimitted) viewing top to bottom:

Data is read from file

First loop applies the average

Second Loop trims the end of the data to remove unwanted trace portion

Third Loop trims the start of the data to remove unwanted trace portion

Finally the averaged and trimed data is saved to file with the word "_Averaged" appended to the file name