Hello everyone,

Recently a customer asked me if there is way in which you can filter the results in Abaqus/Viewer without applying a backward pass filter on the data.

The answer is yes!  If you set the parameter backwardPass to False while using a filter such as butterworth the filtered results will match the results obtained by filtering data in Abaqus/Explicit.

Here is an example:

In this example we intend to apply a butterworth filter to the reaction force RF1 at node 17291 over time.

 In the image shown above we have 3 curves:

RF1_SAE-1000N (red curve) is obtained using the keyword block:

*FILTER, TYPE=BUTTERWORTH, NAME=SAE-1000

 1666.67,

(Note the red curve is hidden under the green curve)

filtered-viewer (purple curve) is obtained by applying the butterworth filter on the raw data i.e., reaction force RF1 at node 17291.

Python CLI commands:

xy2 = butterworthFilter(xyData=xy1, cutoffFrequency=1666.7)

filtered-vwr-no-backpass (green curve) is obtained by applying butterworth filter on the raw data with the option backwardPass set to false.

xy2 = butterworthFilter(xyData=xy1, cutoffFrequency=1666.7, backwardPass=False)

As you can see the curve obtained by filtering data in Abaqus/Explicit (red curve) matches the curve obtained from the viewer (green curve) when the option backwardPass is set to false. For more details on filtering you can refer Section 47.4.26 (Applying Butterworth filtering to an X–Y data object) of Abaqus/CAE User’s manual for release 6.11-1.