PDM-UG: Relating Part Shape Properties to Product Structure
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This page belongs to the PDM Usage Guide.
The PDM Schema allows linking geometric structures that result from relating different shape_representations with associated product structure when applicable, i.e., when the geometric structure directly corresponds to the assembly structure.
Two alternatives for the implementation of geometric structures related to assembly structures are recommended:
- The assembly is described with the components built in. With this approach the shape of the component is mapped into the shape of the assembly via mapped_item. The basic idea of the mapped_item is: an item will become part of another item. The assembly component geometry is used as a template in the assembly geometry.
- The components of an assembly are described together with the construction history. This approach uses the above-described representation_relationship_with_transformation. The transformation describes the relation between different workspaces.
The usage of both alternatives is considered reasonable, because both mechanisms make sense even in mixed combinations. With regard to the transformations in the context of assembly, a part is in principle incorporated in the assembly only by rigid motion (i.e., translation and/or rotation) excluding mirroring and scaling.
