1) How this page is organized

Hover a card for a quick scan, then click it to jump straight to that part of the page.

2) Naming conventions and file relationships

Use stable, descriptive names that include object identity, part identity (if needed), date, version, and file role. Hover or click each segment to see what it contributes.

CoopersHawk_001_wing_exterior_20260220_v01_raw.tif
CoopersHawk_001_master_assembly_20260224_v03_pres.obj
CoopersHawk_001_web_20260224_v01_access.glb

Keep names machine-sortable and avoid spaces or punctuation that can break scripts.

A 3D asset is a package, not a single file

Open the example, then hover or click each file to see how the package works as one connected unit.

Example

View Example File Relationship

Trace how geometry, materials, textures, scene notes, metadata, and paradata stay connected.

The thesis treats 3D data as a compound object. Below are the pieces that may need to travel together:

.OBJGeometry mesh .PNGTexture image .mtlMaterial links .jsonScene or assembly data Metadata.txtObject metadata paradata.txtProcess notes

Geometry mesh

CoopersHawk_001_master_assembly_v03.obj holds the specimen's form. It is the core file, but it still depends on the rest of the package to represent the model completely.

Texture image

CoopersHawk_001_feather_diffuse.png carries color and surface detail. If it gets separated from the mesh and material file, the model may open with the right shape but the wrong appearance.

Material links

CoopersHawk_001_master_assembly_v03.mtl tells software which textures belong on which surfaces and how the geometry should be rendered.

Scene or assembly data

assembly_relationships.json records relationships that do not fit neatly inside the mesh itself, such as transforms, part arrangement, or other structural context needed for reuse.

Object metadata

CoopersHawk_001_Metadata.txt identifies the object, describes capture context, and documents which files belong together in the package.

Process notes

CoopersHawk_001_paradata.txt explains the human decisions behind the model, such as filtering, registration, smoothing, decimation, and export choices.

CoopersHawk_001_preservation_package/
  geometry/CoopersHawk_001_master_assembly_v03.obj
  materials/CoopersHawk_001_master_assembly_v03.mtl
  textures/CoopersHawk_001_feather_diffuse.png
  metadata/object_metadata.txt
  metadata/paradata.txt
  assembly/assembly_relationships.json

Each preview below opens the full image in a new tab, and each card has its own direct page link for sharing.

• Keep linked sidecars together as one identifiable package.
• Record expected directory structure and dependencies in metadata.
• Reopen the package in a second tool after moving it to confirm links still resolve.

3) Characteristics of sustainable 3D file types

Long-term preservation depends on format qualities, not short-term popularity. Guidance from organizations such as the Library of Congress and Duke Libraries prioritizes formats that remain readable across tools and over time.

• Open and documented: technical specifications are publicly available.
• Transparent: structure and content can be inspected without one vendor's software.
• Widely supported: multiple independent tools can open and convert the format.
• Interoperable: data can move between tools with limited loss or lock-in.
• Low dependency: long-term access does not require fragile hardware or discontinued platforms.
• Migration-friendly: geometry, texture, units, and context can be moved without major data loss.

4) Common 3D file formats and where they fit

No single format covers every need. Use different formats for mesh fidelity, point-cloud preservation, access delivery, and print production.

5) Preservation masters vs access copies vs print files

Preservation and delivery have different goals. Keep a master-plus-derivative workflow and retain original scan data whenever possible.

Obsolescence risks to monitor

• Files survive in storage but become unusable because required software or plugins are no longer available.
• Geometry remains but textures, material files, or coordinate context are separated or undocumented.
• Teams lose track of why files were retained, which copy is authoritative, or how derivatives were produced.
• Packages are never reopened after transfer, so broken links remain hidden until much later.

Example: how decimation changes an access copy

In both comparison views below, the left model is the access copy at 10,000 faces and 5.65 MB, while the right model is the preservation model at 1,000,000 faces and 107 MB.

7) Choose the structural model and plan for parts

You have two valid structural models, and for complex machines you will often use both:

If the machine is scanned within a larger survey, keep both contexts:

Projects/
  FactorySurvey_2026/
    Machine_12_WaterPump/

Objects/
  Mechanical/
    WaterPump_001/

• Projects document workflow context and campaign activity.
• Objects document long-term intellectual identity.

Do not collapse these into one folder tree. For complex machines, use project structure for workflow and object structure for durable identity.

Objects/
  Mechanical/
    WaterPump_001/
      assembly/
        WaterPump_001_master_assembly_v01.pres.obj
        assembly_metadata.txt
      parts/
        WP001_P01_Impeller/
        WP001_P02_Housing/
        WP001_P03_Shaft/
      documentation/
        metadata.txt
        paradata.txt
        rights_and_access.txt

WaterPump_001_P01_Impeller
WaterPump_001_P02_Housing

assembly/
  WaterPump_001_master_assembly_v01.pres.obj
  assembly_relationships.json

{
  "parent_object": "WaterPump_001",
  "parts": [
    {
      "id": "WP001_P01_Impeller",
      "connects_to": "WP001_P03_Shaft",
      "connection_type": "rotational_fit",
      "alignment_reference": "central_axis"
    },
    {
      "id": "WP001_P02_Housing",
      "contains": "WP001_P01_Impeller",
      "connection_type": "enclosure"
    }
  ]
}

parent_object: WaterPump_001
part_number: P01
assembly_position: internal rotating component
fits_with: WP001_P03_Shaft

8) Clean rules summary

1. Keep original capture outputs and preservation masters separate from access and print derivatives.
2. Every physical thing gets one object folder.
3. Every removable or distinct component gets a child object folder.
4. Assemblies define relationships, not filenames.
5. Unknown components use placeholders plus documented uncertainty.
6. Projects record workflow; objects record long-term identity.