Standardized CAD Application Relationships (Autodesk Inventor)
This section describes the components necessary for the mapping of CAD external relationships in Windchill. While many categories of external relationship are defined, not all will be used by every application, as not all CAD applications provide access to detailed reference information:
Design Reference - The design external reference is a general category of external reference used in two situations:
When your CAD application generates external reference information which is not granular enough to map to a specific category of reference.
When data is upgraded from an older Windchill release, the external references are also upgraded to the latest version after the first check-in to Windchill.
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"Upgrade" is not mere migration. It refers to the situation where, during or after migration, additional categorization of external reference information is captured in data files.
Assembly Design Reference - An assembly design reference is created when a feature is created in the context of assembly in the assembly components.
Relation Reference -- Relational references are generally not required references. They are created when two items are linked together the by sharing of a physical reference, or by an equation that links the two items. The reference is used by the target, but is not copied to the target. Relation references point to the context in which the relationship was created (for example, an assembly or layout). For example:
Create an up-to-surface protrusion or using holes in one part to position holes in a mating part
Write expressions to drive model A, using model B; or use physical references in the one part to drive a feature in another part
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