ISO 20685-2:2023

Overview

ISO 20685-2:2023 specifies an evaluation protocol for assessing the quality of 3‑D surface-scanning systems used to create internationally compatible anthropometric databases. The standard focuses on two core aspects: the accuracy of surface shape capture and the repeatability of relative landmark positions as determined by an anthropometrist. It is applicable to whole‑body and body‑segment (head, hand, foot) scanners that measure the body in a single view, and it is intended to harmonize performance expectations between scanner users, database providers and manufacturers.

Key technical topics and requirements

• Surface-shape evaluation using calibrated test objects
  • Use of a calibrated test sphere (steel, ceramic or similar diffusely reflecting material) whose diameter and form are traceable to an international standard of length.
  • The test sphere’s spherical form dispersion value (100) shall be smaller than 0.1 mm.
  • The reference sphere supplied with a scanner must not be used for this evaluation.
  • Measurement in at least nine positions across the scanner’s volume to assess spatial performance (including center, multiple heights and lateral/front offsets).
  • Quality parameters include error of diameter measurement and spherical form dispersion.
• Repeatability of landmark positions
  • Protocols for a calibrated test object and predefined landmarks (as determined by an anthropometrist - not automatically calculated by software).
  • Procedures for multiple measurements, calculation of repeatability quality parameters, and standardized reporting.
• Evaluation of hidden areas and motion artefacts
  • Procedures for evaluating portions of the body occluded from a single view and for accounting for errors introduced by participant rotation or hand‑held scanner operators.
  • Guidance on recruitment, posture control and reporting for hidden-area tests.
• Traceability and reporting
  • Calibration certificates for test objects and clear reporting of test conditions, materials and operating modes.

Practical applications

• Ensures quality control for 3‑D scanning in industries such as apparel, automotive seating, ergonomics, digital human modeling and medical anthropometry.
• Helps manufacturers and service providers specify and verify scanner performance for database collection.
• Enables data users to judge fitness for purpose of scan-derived measurements for design, engineering and research.

Who should use this standard

• 3‑D body‑scanner designers and manufacturers
• Organizations creating or using 3‑D anthropometric databases (research centers, apparel and automotive companies)
• Metrology labs conducting scanner verification and calibration
• Ergonomists and anthropometrists responsible for landmarking and data quality

Related standards

• ISO 20685-1:2018 - evaluation protocol for body dimensions extracted from 3‑D scans
• ISO 7250-1:2017 - body measurement definitions and landmarks

Keywords: ISO 20685-2:2023, 3‑D scanning, anthropometric databases, surface shape, landmark repeatability, body scanners, test sphere, spherical form dispersion, evaluation protocol, calibration.