Learning Forum

[Hima2077]

Hello,

I am new to ansys so please be patient. I am using ansys workbench 2019 R2, and I am trying to do modal and harmonic analysis. I am simulating a robot arm that has many joints, and I defined the contact between them with torsional springs. I selected a fixed geometry at the bottom of the robot arm. I specified the force and the frequency response for the harmoinc. I used a cad model that was provided by the manufacturer, I assembled the parts in SolidWorks, and I imported them into ansys. when I tried to mesh, it says some elements failed. I changed the mesh size from default, I tried different sizes, but it did not work until I reached 0.01. when I ran the solver, it had these errors:

*** WARNING ***                        CP =      2.219  TIME= 17:16:48

 Element shape checking is currently inactive. Issue SHPP,ON or        

 SHPP,WARN to reactivate, if desired.                                   

 *** ERROR ***                          CP =      2.641  TIME= 17:16:49

 Element 7441175 has a zero length.                                     

 *** ERROR ***                          CP =      2.641  TIME= 17:16:49

 Element 7441178 has a zero length.                                     

 *** ERROR ***                          CP =      2.844  TIME= 17:16:49

 The model data was checked and there were errors found.                

 Please check output or errors file ( C:UsersEbrahGoogle            

 Driveaaa esearchjune 6 obot arm\_ProjectScratchScr9790file0.err  

 ) for messages.                        

I was not able to attach my file here. can you please help me?

[1shan]

Could you try identifying the violating element. You could use the "Identify Element Violations" option under solution information to locate the elements or use select by id to do the same. The reason probably is a bad mesh. Could you share an image of the mesh and geometry ? If its a big model it might need some geometry cleanup so as to get a good mesh.
Regards Ishan.

[Hima2077]

Hello 1Shan sorry for the late reply, I did not have access to the model. Please check the attached pictures. Identify Element Violations has 0 value in front of it. I am not sure how that was supposed to show me where this element is. I used the selection tool and I could not find that element. I could find element 1 and element 111, but when I type 7441175 I do not see any element in the wireframe view. I can see element 99999, but not 999991. These pictures are with mesh size 0.01, I decreased the mesh size by a half, and the same issue was there. I attached my file.

Best Hima