Product Structure, Identity, and References

A design handoff is more than a set of component shapes. The receiving system may also need the assembly hierarchy, repeated occurrences, configuration context, identifiers, update relationships, and every external dependency required to use the intended whole.

What this category covers

Use this category when a file opens but the design is still not usable for its next purpose. It explains how to describe the product structure that must survive, distinguish an occurrence from copied geometry, reconcile a model with a BOM or report, package or resolve references, and accept a transfer against a real reuse, update, supplier, or archive requirement.

The terms used by CAD, BIM, PDM, and scene-description systems are not interchangeable. A part number, an instance label, a namespace path, and a schema identifier may each be meaningful in its own system without being equivalent across systems. The articles therefore use bounded examples and keep format- or product-specific behavior qualified.

Articles

1. Structure as Data: Why an Assembly Is More Than Its Parts — Define the structural objects and relationships a receiver may need beyond individual shapes.
2. Identity, Instances, and Configurations in a Design Handoff — Specify the identity and variant context needed for reuse, replacement, or controlled updates.
3. Reconciling BOM Views with Model Membership in a Design Handoff — Explain membership, row, depth, and quantity differences before treating them as transfer loss.
4. External References, Dependencies, and Portable Design Packages — Treat a handoff as a dependency graph and choose deliberately between live links, copied packages, and flattened or bound results.
5. Reference State and Update Behavior in Design Handoffs — Check whether links resolve, remain accessible, and update as the receiving task requires.
6. Accepting a Product Structure Transfer: Checks for Reuse, Update, and Archive — Turn the required structure, identity, dependency, and report behavior into purpose-specific acceptance checks.

A useful starting question

Before choosing an export or package, write down the receiving task. Does the recipient need to inspect a fixed snapshot, continue editing, update a linked design, produce a supplier deliverable, select a variant, or retrieve the package years later? The answer determines which structural properties are requirements and which differences can be accepted.

Structure checks complement, rather than replace, checks for geometry, editability, engineering meaning, and downstream use. A matching tree does not prove that shapes are accurate or that feature history survived.