multiple channels matching

[Aleksadner]

Hi,

I am having a problem with multiple channels matching. Namely, I have a lot of waveforms from accelerometers. The main problem is that those readings are from different test rigs and recorded at different time. In consequence, it was impossible to trigger the accelerometers at the same time (see acc1). I was wondering if DIAdem provides an option to rescale the time axis. I did some kind of “walk-around” and shift the entire signal by changing the waveform x-offset to match signals to one another (time-consuming but possible). However, I do not know how to rescale the x-axis to begin from 0 [s]. For example, in acc2 the figure should start from 0, not form 3.6s. could you please advise me on how to rescale the time axis? Also, maybe there is a less time-consuming way to match the signals than changing the waveform x-offset.

Thanks a lot

Aleksander

[Brad_Turpin]

Hi Aleksadner,

The waveform x axis properties are the most efficient way to shift curves "left and right" along the x axis-- the trick is determining the right amount to shift each curve.  I have a script I created that will enable you to interactively time align all the curves on a given VIEW graph (attached), for instance.

There is also an ANALYSIS dialog you can use, the "Synchronize Data From Different Files" in the "Channel Functions" palette.  This is the only ANALYSIS function in DIAdem that requires each curve you select to have been loaded from a different data file, though, so that may or may not fit your workflow either.  Still, it's worth a look.

Brad Turpin

Principal Technical Support Engineer

NI

[Aleksadner]

Hi Brad

That is awesome. The code works like a charm. Thank you very much for your help.

Best whishes

Aleksander