Overview
ISO 11067:2015 - Intelligent transport systems - Curve speed warning systems (CSWS) - Performance requirements and test procedures - defines the minimum functionality, warning strategy, driver interface elements, diagnostics and failure reactions, and the performance test procedures for Curve Speed Warning Systems (CSWS). The standard applies to vehicles with four or more wheels and is focused on systems that warn drivers about excessive speed for upcoming curved roads; it does not mandate automated vehicle control. Responsibility for safe vehicle operation always remains with the driver.
Key topics and requirements
- Basic operation principle: how CSWS locates the vehicle relative to upcoming curved road sections and assesses collision risk based on curvature and vehicle speed.
- Warning threshold speed (V_WT): how the system determines the safe speed threshold for a given curvature point of interest and when a warning must be issued.
- Target curvature and look-ahead: methods to select the target curvature point of interest within the defined look ahead distance (S_LAD) and criteria for single, multiple and variable-radius curves.
- Timing and warning criteria: minimum curve speed warning time, warning end speed, warning distance and driver response time considerations.
- Driver interface and alerts: minimum driver interface capabilities including visual, audible and optional haptic elements, operation controls and system state transitions (on, off, unavailable, warning).
- Diagnostics and failure response: minimum requirements for detecting sensor/map/GNSS faults and transitioning to safe/unavailable states.
- Performance evaluation and test procedures: environmental, test-course and vehicle conditions, system installation/configuration and step-by-step performance tests.
- Definitions and calculation annexes: terms, symbols and informative annexes covering curve definitions, operation principles and calculation of parameters (e.g., minimum angle of curve).
Applications and who uses it
ISO 11067:2015 is intended for:
- Automotive OEMs and Tier‑1 suppliers designing CSWS hardware and software
- Intelligent Transport Systems (ITS) vendors integrating GNSS and digital-map data
- Test laboratories and certification bodies performing performance and compliance tests
- Road authorities and fleet operators evaluating safety features for vehicles (cars, vans, trucks, buses)
- Regulators and standards committees harmonizing vehicle safety and ITS specifications
Practical benefits include improving road safety by providing standardized warning behavior, consistent test methods for validation, and interoperability guidance for map/GNSS-based speed-warning implementations.
Related standards (if applicable)
ISO 11067:2015 was developed by ISO/TC 204 (Intelligent transport systems) and complements other ITS and vehicle safety standards addressing sensors, positioning, digital maps and human‑machine interface design. For implementation, coordinate with relevant ITS standards and national regulatory requirements.