DICAnalysis stops before the end

[AlexandreTlili]

Hello @PolymerGuy and muDIC users !

I have written a little Python script to use muDIC's functions for my needs. I am simply following the tutorial; but I have added a way to manually define the mesh (without the GUI) and keep only desired images.

However, when I run a DICAnalysis job, it often happens that the routine stops before going through the whole image stack.

I have checked that the parameters I have given to the DICInput object are noconverge="ignore" and max_nr_im=None (default). If I understand the code correctly, when max_nr_im=None, its value should be set to the length of the image stack. So I do not understand why the DICAnalysis job stops sooner than expected.

Attached are my Python script compute_DIC.txt and its output.txt. In this example, the length of image stack was 720, but only the first 95 images were analyzed.

Note : I can not send a .py file on GitHub, so I sent a txt file. A screenshot of the first part of the script is also .

If you have any idea why the job stops, I would really appreciate your help.

Have a nice day

[Skaraa]

Any new insight on the issue ? Got the same problem...

[PolymerGuy]

Hi! My apologies for my absence. My situation has been such that I have not been able to follow this repo as I should. My guess is that the update reference routine crashes due to distorted elements. I should obviously report a error message as that happens, but somehow this is not triggered. Can you share a picture of the mesh the frame before the reference update?

[Skaraa]

Hi! My apologies for my absence. My situation has been such that I have not been able to follow this repo as I should. My guess is that the update reference routine crashes due to distorted elements. I should obviously report a error message as that happens, but somehow this is not triggered. Can you share a picture of the mesh the frame before the reference update?

Sure, here it is :

[Skaraa]

I've also managed to log the error :

Traceback (most recent call last):
File "C:\Users\alexa\AppData\Local\Programs\Python\Python310\lib\site-packages\muDIC\solver\correlate.py", line 200, in correlate
reference = gen_ref(node_coords, mesh, images[image_id - 1], settings, image_id=(image_id - 1))
File "C:\Users\alexa\AppData\Local\Programs\Python\Python310\lib\site-packages\muDIC\solver\correlate.py", line 129, in wrapper
ref = reference_generator(*args, **kwargs)
File "C:\Users\alexa\AppData\Local\Programs\Python\Python310\lib\site-packages\muDIC\solver\reference_q4.py", line 102, in generate_reference_Q4
epE[el], nyE[el], Xe[el], Ye[el] = find_element_coordinates_q4(node_coords[0,mesh.ele[:, el]], node_coords[1,mesh.ele[:, el]], elm)
File "C:\Users\alexa\AppData\Local\Programs\Python\Python310\lib\site-packages\muDIC\solver\reference_q4.py", line 78, in find_element_coordinates_q4
ep, ny = elm_coords_from_global_q4(np.array([xnod[elm.corner_nodes], ynod[elm.corner_nodes]]).flatten(), X, Y)
File "C:\Users\alexa\AppData\Local\Programs\Python\Python310\lib\site-packages\muDIC\solver\reference_q4.py", line 57, in elm_coords_from_global_q4
nn1 = xi1(a1, b1, c1)
File "C:\Users\alexa\AppData\Local\Programs\Python\Python310\lib\site-packages\muDIC\solver\reference_q4.py", line 38, in
xi1 = lambda ai, bi, ci: 2. * ci / (-bi - (bi ** 2. - 4. * ai * ci) ** 0.5)
FloatingPointError: invalid value encountered in sqrt