Inventor Assembly Hierarchy Issue: Model States & Position Reps in Nested Sub-Assemblies

[deodoro_filho]

Hey,

I'm facing a puzzling issue with Inventor assemblies involving Model States and Position Representations in a nested hierarchy.

Here's the setup: I have a "Master" assembly with a hierarchical structure of sub-assemblies. This allows me to manage different product configurations (via Model States) and display various component positions (via Position Representations).

The core problem lies within a specific Sub-Assembly A. Inside Sub-Assembly A, there are two instances of another sub-assembly, let's call it Sub-Assembly B. Each instance of Sub-Assembly B occupies a distinct Model State and Position Representation within Sub-Assembly A. These internal positions for Sub-Assembly B are predefined and locked; they're not intended for free movement.

• When Sub-Assembly A is placed directly into the "Master" assembly, the internal Position Representations of both Sub-Assembly B instances work perfectly. Their components move to their correct, defined locked positions as expected.

• However, when Sub-Assembly A is placed within an intermediate sub-assembly (meaning, it's not at the very top level, but a sub-assembly of a sub-assembly), one of the Sub-Assembly B instances fails to produce the expected movement, while the other does.

I've already confirmed:

• Sub-Assembly A itself has no errors and functions correctly when placed at the Master level.

• The "Flexible" setting is NOT the solution for Sub-Assembly A, as its internal positions (and thus Sub-Assembly B's positions) are predefined and locked, not intended for free movement.

Getting this to work at the intermediate level is crucial for my 2D drawing workflow and will avoid significant rework.

Has anyone encountered similar behavior with nested sub-assemblies (like A containing B) where Position Representations (or Model States interacting with them) behave differently depending on their hierarchy level? Any insights or troubleshooting tips would be greatly appreciated!

Inventor 2022

Thanks in advance!

Deodoro B.

[hollypapp65]

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@deodoro_filho wrote:

• However, when Sub-Assembly A is placed within an intermediate sub-assembly (meaning, it's not at the very top level, but a sub-assembly of a sub-assembly), one of the Sub-Assembly B instances fails to produce the expected movement, while the other does.

Those sub-assembly need PosRep for each PosRep in Sub-A.

[johnsonshiue]

Hi Deodoro,

Without seeing the files, I can only speculate. It is possible one of the subassemblies is corrupted. You may want to open the subassembly in its own window. Next, save it as a different assembly. Then try demoting the components to a new subassembly. After that, go back to the top-level assembly and replace the current subassembly with the newly demoted subassembly. This will help you purge any corruption existing in the old subassembly.

Please feel free to share the files here. The forum experts can help take a look.

Many thanks!