Overview
ISO/TR 21718:2019 is a Technical Report from ISO/TC 204 that defines a spatio‑temporal data dictionary for cooperative ITS and automated driving systems 2.0. It compiles standardised terms, data concepts and meta‑attributes needed to describe both static (maps, road signs, buildings) and dynamic (traffic conditions, accident reports, vehicle position) spatial‑temporal information for Intelligent Transport Systems (ITS). This second edition updates and expands the 2017 edition and incorporates collaboration with SAE, including a mapping to SAE J2735 data concept names.
Key topics and technical requirements
- Data concepts and types: clear definitions for data element, data frame, value domain, aggregate domain, message, module and related classifications used in an ITS data dictionary.
- Static vs dynamic data: classification and examples (e.g., static: road geometry, signs; dynamic: vehicle position, ambient air pressure).
- Data dictionary structure: required fields such as data concept name, type, status (dynamic/static), definition, XML schema definition, source and remarks.
- Machine‑readable schemas: illustrative XML Schema (XSD) fragments are included for many data concepts (examples: AbsoluteGeoCoordinate with 24‑bit deca‑micro degree coordinates; Acceleration and AccelerationSet).
- Metadata and provenance: guidance for issuing authority, source documents and versioning (modules as version‑controlled units).
- Interoperability focus: harmonisation with SAE J2735 message set and other ITS specifications to promote common understanding and reuse.
Applications and who uses it
ISO/TR 21718:2019 is intended for practitioners designing and operating cooperative ITS and automated driving systems:
- Vehicle OEMs & ADAS/ADS developers - to standardise vehicle telemetry and object/state definitions.
- Map providers & geospatial data engineers - for unified coordinate, altitude and road feature representations.
- Road operators & traffic management centres - to exchange dynamic traffic events and advisory points.
- Telematics/RSU/OBU vendors - to implement interoperable messages and sensor data formats.
- Standards bodies and integrators - to harmonise cross‑jurisdiction data sharing and reduce duplication of effort.
Practical benefits include improved data interoperability, reduced integration costs, and accelerated deployment of cooperative ITS services and automated driving features.
Related standards
- SAE J2735 (DSRC Message Set Dictionary) - included as an annex mapping.
- ISO/TS 21219‑22 and ISO 14296 - referenced for specific data concept implementations.
- Work coordinated under ISO/TC 204 (Intelligent transport systems).
Keywords: ISO/TR 21718:2019, spatio‑temporal data dictionary, cooperative ITS, automated driving systems, intelligent transport systems, SAE J2735, data element, data frame, XML Schema.