Display Values for Alignment Transformation Matrix

[[Jo...]]

Hello,

I'm working on a reverse engineering type project in which I have aligned a mesh to a CAD part model in GOM.  The mesh model was derived from die cavity scans and is in the proper location with respect to my die model, the CAD part model is not in proper location (e.i. the mesh aligns with the die model in my CAD software, but the CAD is off in arbitrary space).

I would like to know if there is a way to capture the transformation that GOM used to align the mesh and CAD and then reverse it in my CAD software to bring the CAD model into the same alignment it is in GOM. 

I came across this thread which seemed like it was on the right track: 

Any other suggestions for how to accomplish this task would be appreciated.

Regards,

Josh

[[Ad...]]

Hi Mr. Joshua

 

Here is a solution , script with export to json file.

[[Jo...]]

Hello Adam,

Thanks for the response.  At first glance this appears to be what I'm looking for.  I'm not familiar with scripting in GOM.  Did you create the script within GOM or did you have to use another script editor?

Also, do you happen to know what value in the matrix corresponds to what movement?  For example, when I go to Alignment->Set Matrix, I am presented with 6x options (3x for rotation and 3x for translation).  I see your script outputs 16x values...

Thanks,

Josh

[[Ad...]]

Hi Joshua

I use GOM script editor. In the top menu Scripting->Edit Script. But for scripting You need to have "GOM Professional" , it is not available in free version.

This is 4x4 matrix.

Below is link to GOM Faq with some description, it is possible to extract rotation and translation components:

https://connect.gom.com/display/GKB/Definition+of+the+gom.Mat4x4+matrix

 

But easier for You would be to access these values via report page :

1. create report page

2. insert label

3. insert keywords

[[Jo...]]

Hello Adam,

Getting the values within the report pages is perfect for my application.  I will try that method and see if I can get the results I'm looking for.  Thanks for your help!

Regards,

Josh

[[Jo...]]

Hello Adam,

Just had the chance to try this out.  Works perfectly, thanks again for your help!

For anyone else looking into this,  I was able to move the CAD model into alignment with the mesh model in my CAD packaged (NX 12) by creating an offset CSYS based on the same absolute CSYS.

I chose the "rotate first" option and reversed the direction of each translation and rotation.  I then moved the CAD component using the "CSYS to CSYS" option.  The CAD and mesh lined up perfectly.

[[Be...]]

Hi, 

one additional hint: The rotation order (which we derive from the matrix representation) is Y-X-Z. You have to respect this if you apply the rotation values in other programs. If the third party program does not allow to specify the rotation order you have to apply each rotation as a single step and afterwards you have to apply the translation (as you already mentioned)

Hope this helps?

Regards,

Bernd