Overview
EN ISO 14406:2010 - Geometrical product specifications (GPS) - Extraction defines the basic terminology and conceptual framework for extracting geometrical information from measured surfaces. Published by ISO and adopted by CEN as EN ISO 14406:2010, the standard introduces sampling and reconstruction concepts for GPS extraction and describes principal sampling schemes for common geometries. It targets the digital-processing stage where physical surface measurements become primary extracted surfaces used for filtering, characterization and verification.
Key Topics
- Scope and terminology for GPS extraction including definitions of skin model, real surface, mechanical surface, and electromagnetic surface.
- Primary mathematical model and primary surface concepts: nested representations indexed by a nesting index and described by a finite number of parameters (degrees of freedom).
- Primary extracted surface: finite sets of data points sampled from the primary surface - the basis for digital filtering and parameter calculation.
- Sampling and reconstruction:
- Reconstruction methods that select a primary mathematical model passing exactly through sampled points.
- Concept of exact reconstruction and risks such as sampling aliasing (multiple models fitting the same samples).
- Filtering concepts relevant to extraction:
- Wavelets (exact reconstruction properties)
- Morphological filters and associated reconstruction zones (e.g., circular disk, horizontal-line structuring elements)
- Sampling schemes covered (principal examples):
- Orthogonal grid (including variants such as birdcage and polar-grid arrangements)
- Specified grid
- Stratified sampling
- Helical, spiral and spider-web patterns
- Points-method sampling
- Relationship of extraction concepts to the GPS matrix model and measurement uncertainty considerations.
Applications and Users
EN ISO 14406:2010 is practical for organizations and professionals involved in:
- Coordinate and surface metrology (metrologists, lab managers)
- Quality assurance and inspection engineers converting sensor outputs into verification data
- Developers of measurement software and signal-processing algorithms (sampling, reconstruction, filtering)
- Manufacturers of tactile and optical measurement instruments (scanners, interferometers)
- Product designers and tolerance engineers who rely on robust surface characterization for function and fit
Typical applications include surface characterization, datum and form extraction, reverse engineering, digital filtering before tolerance evaluation, and choosing sampling strategies to avoid aliasing.
Related Standards
Key normative references and adjacent GPS standards:
For implementation, refer to EN ISO 14406:2010 alongside these GPS standards to ensure coherent terminology and compliant extraction practices.
