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After optimization, when comparing the results, the mass appears to have increased compared to the o

I’m a beginner with this software, so I’d like to ask not only about the issue but also how to use it.

When clicking the "Comparison of Results" tab after performing structural optimization, the optimized result is displayed, but the displayed mass value is clearly incorrect.
The optimization conditions were:

Maximization of stiffness
Target mass: 70%

Even when overlaying the original shape, there is clearly no added volume, yet the mass has increased.

No structural overlap has been detected, and even when checking with other software, no overlap was found.　There might be some kind of overlap that is counted only within this software, but I don’t know how to display or check for that.

If anyone knows why this might be happening, I would greatly appreciate your insights.

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loistf

I am not sure exactly about your process, and how you are measuring mass and from which data, but I believe I might have some valuable input, hopefully. When comparing mass after topology optimization, it is important to understand that the results of topology include all the elements in the design space with a certain value of density (from 0.0 to 1.0). If, with these results, you create a cad file by defining a threshold, the mass will be different than in the topology result. That is expected.

Once the cad is generated, it should match the volume that other cad programs measure.

Does this help?

loistf

Maybe you can ellaborate how you are measuring the mass? If you use a dummy , simple model that you can share here, we can look at the values together. Hopefully that would clarify.

All comments

loistf

Once the cad is generated, it should match the volume that other cad programs measure.

Does this help?

北川理子

Thank you for your response. The idea that the results of topology include all the elements in the design space with a certain value of density (from 0.0 to 1.0) is a new insight for me, and I would like to take it into consideration moving forward. However, this alone does not explain the increase in mass, so the issue remains unresolved. I believe I might have some valuable input, so I will continue to investigate. Thank you again.

loistf

Maybe you can ellaborate how you are measuring the mass? If you use a dummy , simple model that you can share here, we can look at the values together. Hopefully that would clarify.

北川理子

I'm sorry for the delayed reply. I contacted support regarding this issue, and they informed me of the following:

In the comparison of results, shapes created using Poly NURBS were also included in the total, which led to an increase in mass.
The tab for measuring mass (the red scale icon displayed at the top right of the Measure panel) is also available in the upper ribbon, allowing you to measure the mass of individual parts.

In addition, I received various insights that contributed to my personal growth. Thank you very much again for your response.