Working procedure - find forces, export and import forces in Hypermesh and optimize the topology of a part

FloMa93
FloMa93 Altair Community Member
edited October 2020 in Community Q&A

Hi Community,

 

I am currently working on a project to optimize the topology of an robot arm. 

Specification is as follows: Rigid bodies, extract forces by using MotionView, optimize robot arm with Hypermesh / Optistruct.

Attached a picture of the roboter, the red robot arm is the one to optimize.

 

Therefore I made a simulation with MotionView - Robot picks a cube, lifts, rotates and puts it back down, then it rotates back without the cube.

To get the forces acting on this robot arm (or on the 2 joints of the robot arm) I placed 2 Outputs on the joints. Now I used the tutorial MV-3030: Load Export to get these forces.

I tried to import these in Hypermesh to use it for optimization, but I don't know how.

 

My questions:

- How to get forces / loads from MotionView to Hypermesh?

- Is the procedure I am trying currently correct or is there another way to optimize a part?  

- What's the usual procedure to solve a problem like this?

- I found out that there's the Equivalent Static Load Method, but it's only usable with flexible bodies... is there a possibility to use it with rigid bodies?

 

Thanks in advance and best regards,

Flo

<?xml version="1.0" encoding="UTF-8"?>Roboter.jpg

Answers

  • asajd_20372
    asajd_20372 New Altair Community Member
    edited November 2019

    If you use Inspire then you can optimize the topology of a part in 'one click'.

    1. open CAD files in Inspire

    2. organize model into design space and non-design space parts (use partitions)

    3. mechanize the model (ground, rigid groups, joints, motors)

    4. define design space

    5. run a motion event.

    6. click 'Optimize Part' and run the optimization.

    7. when optimization run finishes you have a new topology shape for the part.

     

    Optionally you can export the .fem deck in step #5 if you prefer.

     

    Attached video shows one of the motion tutorials on this in Inspire 2019.3

    Unable to find an attachment - read this blog

  • FloMa93
    FloMa93 Altair Community Member
    edited November 2019

    Hi,

     

    thanks a lot for the tip with Inspire, I will clarify with my professor if it's possible this way.

     

    Is there another way using MotionView and Hypermesh in combination, as described in my first post?

     

    Regards

    Flo

  • Chris Coker_21312
    Chris Coker_21312 New Altair Community Member
    edited November 2019

    Hi Flo-

    The short answer is yes.

    1. First change you need to make is to your outputs.  You need to create Force outputs on each Body of interest, not the joints.

    2. When you run the your simulation a .meta file will be created (because you have a model with Force Outputs on Bodies)

    3. Use the Load Export Utility (instructions in our help) to export the loads of interest.  It will need to read in the .meta file created during the run.  The utility will export loads in a tabular format, or in a format compatible with Optistruct

     

    Chris

  • FloMa93
    FloMa93 Altair Community Member
    edited November 2019

    Hi Chris,

    thanks for your reply.

    This is what I already did, but I've got some problems to get these extracted loads into Hypermesh. There is following error while importing the Loads:

     

    ...

    Error:      Unable to find load id 2794 to attach attribute to.
                    Resolution:  Attribute data ignored.
    Error:      Node 0 was not found in model.
                    Resolution:  Entities attached to this node will be skipped.

    ...

    Error is repeating.

     

    I searched in the forum and in the tutorials but didn't find anything.

    I hope you can help.

     

    Regards

    Flo

     

  • Chris Coker_21312
    Chris Coker_21312 New Altair Community Member
    edited November 2019

    My background is mainly with MotionView. Now that you have successfully exported the loads, you may want to pose your question in the Hypermesh forums to get a better answer with that product.

    One tip when you export the loads using the Load export utility, you can specify the specific grid ID numbers you wish to apply the loads to.  These should be ID's that already exist in the FE model.

     

    Kind regards,

    Chris