Incorrect position of Center of Gravity in assembly

[Odalv_Arkonski]

Hello!

I am using Inventor 2026.0.1.

I have an issue with the Center of Gravity (CoG) in an assembly. Inside the main part, the CoG is positioned as expected, and I believe it is correct.

 

After placing this part into an assembly and adding some other components, the CoG remains in the correct position, only slightly shifted from the original point, which is expected.

 

However, after I place additional small and lightweight parts, the CoG shifts significantly away from where it should be.

 

I have checked the material properties for all parts, and I have tried suppressing and deleting certain components.

The issue with the CoG position is also noticeable when the assembly is simplified by removing large parts. The resulting part retains the CoG position from the full assembly.

To check if these side plates are affecting CoG position that much, I have tried to model it in the main part. This hasn't changed the position of CoG at all.

 

Any clues as to what may be causing this behavior?

[Odalv_Arkonski · Accepted solution]

After further experimenting, it appears that the BOM structure affects the position of CoG.

In the above-mentioned example, it was related to the BOM structure of the main part.

The BOM structure was set to "Reference." After I changed it to "Default," the CoG triad has gone back to the right place.