Feature Extraction is how you author a Feature Set for 3D Auto-Dimensioning. A Feature Set is the collection of geometric primitives Voyager measures to and from: planes, cylinders, and a full-part mesh used by Profile.
Extraction is no longer a single fixed-detail click. In Dimensioning Mode, the Features toolbar button opens a workflow with a detail slider and four live readouts that update as you drag, so you can see what you will get before you run it.
Author a Feature Set: open Features, set detail with the slider, and review Resolution, Voxel size, Smallest radius, and Thinnest wall before you run extraction.
What a Feature Set is
Dimensional features are geometric primitives extracted from full-resolution reconstruction data. Extraction runs once on the parent reconstruction. Every ROI built on that reconstruction inherits the resulting Feature Set. Adding or editing an ROI does not re-run extraction.
The returned features are:
- Planes
- Cylinders
- A full-part mesh used for Profile Analysis
Those primitives — automatic and manually authored — are the inputs to Direct Dimensions, Flatness, Cylindricity, Datums, and Profile.
Extraction works best on monomaterial, low-attenuation parts. Mixed-material assemblies and high-attenuation alloys may produce noisier features; reach out to Lumafield to discuss your application.
Open Dimensioning Mode
Switch to Dimensioning Mode and select the parent reconstruction (or an ROI that inherits from it). Open Features
Choose Features in the Toolbar.
Set the detail slider
Drag the detail slider. Four readouts update live: Resolution, Voxel size, Smallest radius, and Thinnest wall. Use them to judge what the Feature Set will resolve before you commit.
Choose a setting that matches the part
Finer detail is the right choice for small pins, thin rims, and threaded holes. Coarser detail is faster and is often enough when you mainly need large planes. Watch Smallest radius and Thinnest wall against the smallest geometry you care about.
Submit
Run extraction. When it finishes, planes, cylinders, and the full-part mesh appear in the Viewport and Data Panel. Child ROIs on that reconstruction show the same Feature Set.
Work with Lumafield to integrate Auto-Dimensioning into Recipes for fully automated GD&T runs across a fleet of scans. Algorithm v20 or newer
Manual Feature Authoring requires a Feature Set extracted with algorithm v20 or newer. On an older extraction, the Features controls used for authoring are greyed out and a tooltip explains why.
To enable authoring on an older Project, re-run Feature Extraction on the parent reconstruction. Re-extracting replaces the previous Feature Set on that reconstruction. After a v20 (or newer) run, authored features behave like automatic ones: selectable, measurable, and usable as datums.
Feature Extraction v20 and later also produce more complete surfaces, which yields cleaner full-part Profile evaluations.
When to author features by hand
Automatic extraction is the starting point. Use Manual Feature Authoring when you need control over thin rims, disconnected components, small patches that mimic CMM probe points, or any surface the automatic Feature Set missed or over-included.
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