Optistruct ERROR # 1461

Mhd saeed Albadawi

I am attempting to perform a topology optimization based on static load and frequency response analysis. I am using the "compliance index" response to consider various load cases. However, I encounter the following error message:

*** ERROR # 1461 *** in the input data:
 Card "WEIGHT" is not allowed for this subcase type

Rajashri_Saha

Hi Saeed,

It is difficult to tell without the model.

I am attaching an example for you with compliance index as response.

Please go through it and set up accordingly.

Thanks

Rajashri

Mhd saeed Albadawi

Thank you for your help. I notice that in the Compliance Index Response, you only imported static loads and not the NM load case. Will the NM load case still be considered in the topology optimization?

Mhd saeed Albadawi

And I have another question. I want to create a stress constraint. Should I use the FRF stress or static stress response? Or should I define that in the design variable parameters under stress constraint?

Rajashri_Saha

Mhd saeed Albadawi said:

Thank you for your help. I notice that in the Compliance Index Response, you only imported static loads and not the NM load case. Will the NM load case still be considered in the topology optimization?

It will consider internally the modal case.

Rajashri_Saha

Mhd saeed Albadawi said:

And I have another question. I want to create a stress constraint. Should I use the FRF stress or static stress response? Or should I define that in the design variable parameters under stress constraint?

If you are defining the stress constraint in DTPL card then it will consider only vonmises stress. If you have other stresses as constraint like principal, major principal, minor principal etc. then in that case you can define it as a static stress response in DRESP1 card and give the value accordingly in constraint parameter. According to your requirement you can go for static stress or FRF stress.

Thanks

Rajashri

Rajashri_Saha

Mhd saeed Albadawi said:

And I have another question. I want to create a stress constraint. Should I use the FRF stress or static stress response? Or should I define that in the design variable parameters under stress constraint?

Hi,

You can do it both ways either in DRESP1 card or DTPL card with response type as Static stress. If it is created in DTPL card then it will consider only vonmises stress and in DRESP1 card you can select other stress too like principal, major minor etc.

See the below pic for differences.

Thanks

Rajashri