Rotation problem

Submitted by shahabgol on Tue, 11/25/2014 - 08:44

Dear all,

I have problem with rotating the geometry stl file in LIGGGHTS.
without rotation everything is working well and no problem occurs but when I insert the following rotation line to the script:

fix movecad1 all/move/mesh mesh cad1 rotate origin 0. 0. 0. axis 0. 1. 0. period 1

this error happens:
ERROR: Could not find fix group ID (modify.cpp:657)

Forums:

j-kerbl's picture

j-kerbl | Tue, 11/25/2014 - 10:04

Hi shabagol,

between all and move/mesh should be a blank and not a "/", since all is the group name!
Therefore it cannot find the group ID.

Cheers
Josef

shahabgol | Tue, 11/25/2014 - 12:11

Thank you very much Josef,

This problem is solved.
I have another problem here. I make two geometries for a mixer in Autocad 2013 (mixer body.stl and impellers.stl, and the impeller shaft locates exactly at the center of the cylinder body). When I export files in the .stl format, the impeller shaft moves and does not locate at the center of the body.
Can I fix this problem using Autocad? or are there any other software to help me solve this problem?

aaigner's picture

aaigner | Tue, 11/25/2014 - 15:33

Hello shahabgol,

Unfortunately I don't know Autocad very well, but may be you can choose the reference coordinate system. It seems that you are currently using local coordinate systems for each body.
So...

  • You can check if you can use the global coordinate system. Take care, it may be that you have to addept your simulation domain.
  • Move the geometry in the LIGGGHTS input script to the correct position. ('move' option for the fix mesh/gran)

Bests
Andreas