Modules: Assembly structure

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(draft) Question: Does the AP210 E 2 model support using Assembly_component_relationship (or one of is subtypes such as Next_assembly_usage) to make an Information_definition a component of an assembly. The desire is to be able to assign an item number to an Information product in an assembly context for communicating engineering design intent information.

Answer: The model supports this application but not with an explicit mechanism. The details of model application are provided below.

Explanation: In the case of a part-assembly we have typically a chain of

• Assembly_definition
• (Assembled_part_association+Next_assembly_usage)
• Definition_based_part_occurrence
• Part_view_definition

This chain (or via Specification_based_part_occurrence) is enforced with the global rule Mandatory_part_occurrence_definition_relationship in module item_definition_structure and further constraints on Part_occurrence_definition_relationship

For the case of Information_definition we don't have an occurrence concept and there are no additional rules enforcing this.

Document_assignment and Information_assignment should not be treated as an assembly relationship because they will not show up in an BOM.

Note also that Assembly_item_number may be used to assign an item-number to a group of components within an assembly.