Fetch parent assembly's position for a sub-assembly part

Question:
I would like to include the position number of the footing in the anchor bolt's properties in the IFC export. How could I do that?

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Answer:
I suppose that the anchor bolt is a sub-assembly below the footing-assembly, and the object that we want to insert the property is a part inside the sub-assembly. To get to the main assembly's level, you need to climb from the part level first to its assembly level (to reach the sub-assembly), and then continue to the main assembly level.

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When climbing up in a model hierarchy to fetch higher hierarchy level attribute values, you need to add prefix "ASSEMBLY." to the property you're calling. So for instance, if you want to fetch the assembly position of the anchor bolt sub-assembly for the part, you call ASSEMBLY.ASSEMBLY_POS. But now that we want to write on the sub assembly part the position number of the footing (main assembly), we need to call it by ASSEMBLY.ASSEMBLY.ASSEMBLY_POS.

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When exporting the model with this additional property set, you'll find the footing's position number on the anchor bolt part's information.

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Note that this same property will be written to all IfcBeam entities, so the naming of the property may not be valid for all of the other objects.