Learning Forum

[Tirtharaj Banerjee]

Hello Sir,

I need to find three dimensional micromovements of a hip stem with respect to bone. Ansys provides in-built option (SLID COMMAND) for evaluating sliding distance. But the software treats it as a scalar quantity, and I need all the X, Y, Z micromovement values.

What I have done so far...

I have identified the target node IDs that are matched with the contact node IDs based on their initial undeformed nodal locations by using a custom-written python script. Now, I subtracted the target directional deformation from contact directional deformation per each matched node and got deltaX, deltaY, deltaZ values. I thought this would give the three-dimensional micromovement values per each node. But, when I took resultant (sqrt(deltaX^2 + deltaY^2 + deltaZ^2)) of these directional deformation values, it did not match with the sliding distances readily available as an in-built option. For very few contact node IDs those did match. But for majority of the contact node IDs, those did not match. I have also combined sliding distance and gap in various ways (as micromovement is a combination of sliding distance and gap), but none of them really worked.

Please let me know where I am going wrong.

Any suggestions regarding any methods are truly helpful. Thanks in advance.

[dlooman]

Seems like your python method should work.  It can be done in POST1 with APDL also:

/post1

set,last          ! store some result

node_1=100  ! hypothetical node numbers

node_2=200

delta_x=ux(node_1)-ux(node_2)

delta_y=uy(node_1)-uy(node_2)

delta_z=uz(node_1)-uz(node_2)