ISO 23132:2020

Road vehicles — Extended Vehicle (ExVe) time critical applications — General requirements, definitions and classification methodology of time-constrained situations related to Road and ExVe Safety (RExVeS)

This document defines the classification methodology of time-constrained situations and their requirements, that are to be addressed by the "ExVe time critical interfaces" described in ISO 20077‑1. Time-constrained situations include safety-critical situations. It is important for the design of the vehicle to have priority management of "ExVe time critical interface" resources in order to comply with time constrained situations requirements. The methodology provides a classification, which determines application priorities for optimal vehicle resource allocation.

Véhicules routiers — Applications temps critiques du véhicule étendu (ExVe) — Exigences générales, définitions et méthodologie de classification des situations sous contrainte de temps liées à la sécurité routière et à la sûreté du véhicule étendu (RExVeS)

General Information

• Status: Published
• Publication Date: 09-Jul-2020
• ICS: 43.040.15 - Car informatics. On board computer systems
• Technical Committee: ISO/TC 22/SC 31 - Data communication
• Drafting Committee: ISO/TC 22/SC 31 - Data communication
• Current Stage: 9020 - International Standard under periodical review
• Start Date: 15-Jul-2025
• Completion Date: 15-Jul-2025

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 23132
First edition
2020-07
Road vehicles — Extended Vehicle
(ExVe) time critical applications —
General requirements, definitions and
classification methodology of time-
constrained situations related to Road
and ExVe Safety (RExVeS)
Véhicules routiers — Applications temps critiques du véhicule
étendu (ExVe) — Exigences générales, définitions et méthodologie
de classification des situations sous contrainte de temps liées à la
sécurité routière et à la sûreté du véhicule étendu (RExVeS)
Reference number
©
ISO 2020
© ISO 2020
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ii © ISO 2020 – All rights reserved

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Symbols and abbreviated terms . 3
5 Conventions and guidelines for specifying RExVeS-related requirements.3
6 The RExVeS methodology . 3
6.1 General . 3
6.2 Analysis of RExVeS-related scenarios . 4
6.3 Classification of RExVeS-related time-constrained and safety-critical situations . 5
6.3.1 Classification scheme . 5
6.3.2 Classes of severity . 6
6.3.3 Classes of probability of exposure . 6
6.3.4 Classes of controllability . 6
6.3.5 Determination of the priority class of a RExVeS-related time-constrained
situation . . 7
6.3.6 Template for the description and priority class assignment of a RExVeS-
related situation . 8
7 Connected vehicle design prerequisites . 8
Annex A (normative) Template for the description and priority class assignment of RExVeS-
related situations (including safety-critical situations) . 9
Annex B (informative) Example 1 of use of the RExVeS template .10
Annex C (informative) Example 2 of use of the RExVeS template .14
Annex D (informative) Example 3 of use of the RExVeS template .18
Annex E (informative) List of use-cases .21
Bibliography .23
Foreword
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electrotechnical standardization.
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different types of ISO documents should be noted. This document was drafted in accordance with the
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This document was prepared by Technical Committee ISO/TC 22, Road vehicles, Subcommittee SC 31,
Data communication.
Any feedback or questions on this document should be directed to the user’s national standards body. A
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iv © ISO 2020 – All rights reserved

Introduction
Preventing death and serious injury in road traffic crashes is a global priority. With the advent of
vehicular data communications, road vehicles become connected vehicles, and safety is one of the key
issues in the development of such road vehicles. ISO 26262-1 defines the vehicle safety as the absence
of unreasonable risks that arise from malfunctions of the E/E system. The absence of unreasonable
risk due to these potentially hazardous behaviours related to specific limitations (identified in
[7]
ISO/PAS 21448 ) is defined as the safety of the intended functionality (SOTIF). Functional safety
(addressed by the ISO 26262 series) and SOTIF are distinct and complementary aspects of safety.
This document defines a complementary methodology for the prioritization of safety-related external
communication use-cases to help to design extended vehicle time-critical interfaces described in the
ISO 20077-1.
NOTE 1 ISO 20077-1 defines the concepts and terms related to the extended vehicle (ExVe), whereas
ISO 20077-2 specifies general rules and basic principles that the manufacturer of the ExVe considers when
elaborating its own design method.
NOTE 2 ISO 20077-1 defines an "extended vehicle" (ExVe) as an "entity, still in accordance with the
specifications of the vehicle manufacturer, that extends beyond the physical boundaries of the road vehicle and
consists of the road vehicle, off-board systems, external interfaces, and the data communication between the
road vehicle and the off-board systems". Road vehicles without off-board systems and road vehicles equipped
with telematics units are extended vehicles.
Recent developments in the field of connected vehicles, in various parts of the world, bring hope of being
able to improve road safety, e.g. by reducing the number of road fatalities through collision avoidance
cooperation. Connected vehicles taking into account ISO 20077-1 and ISO 20077-2 take their part in this
global effort.
Due to the limited per design embedded resources, a priority management is necessary to apply these
resources to the function and request with the highest criticality.
For these connected vehicles, the use of the “ExVe time critical interfaces" is firstly associated with
safety-critical functions (e.g. emergency braking, steering) that are functions for which the priorities
are based on a criticality concept.
It is important that all the functions using the “ExVe time critical interfaces” take into account the
capabilities of the vehicles in which they are installed.
During the design phase, the connected vehicle behaviour regarding all safety-critical situations and its
interactions with the external environment should be defined. Its implementation can be based on the
methodology proposed in this document.
INTERNATIONAL STANDARD ISO 23132:2020(E)
Road vehicles — Extended Vehicle (ExVe) time critical
applications — General requirements, definitions and
classification methodology of time-constrained situations
related to Road and ExVe Safety (RExVeS)
1 Scope
This document defines the classification methodology of time-constrained situations and their
requirements, that are to be addressed by the “ExVe time critical interfaces" described in ISO 20077-1.
Time-constrained situations include safety-critical situations.
It is important for the design of the vehicle to have priority management of "ExVe time critical interface"
resources in order to comply with time constrained situations requirements.
The methodology provides a classification, which determines application priorities for optimal vehicle
resource allocation.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 20077-1, Road Vehicles — Extended vehicle (ExVe) methodology — Part 1: General information
ISO 20077-2, Road Vehicles — Extended vehicle (ExVe) methodology — Part 2: Methodology for designing
the extended vehicle
ISO 26262-1, Road vehicles — Functional safety — Part 1: Vocabulary
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 20077-1, ISO 20077-2,
ISO 26262-1 and the following apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
3.1
road and ExVe safety
RExVeS
set of means (e.g. use cases), conditions and requirements to be considered by the “ExVe time-critical
interfaces” described in ISO 20077-1, including time-constrained and safety-critical situations (3.4)
Note 1 to entry: The intent is to minimise risk of harm (as described in ISO 26262-1) in road safety-related
situations.
Note 2 to entry: In the context of RExVeS, a use case is a set of scenarios (3.2) that have a common goal.
3.2
scenario
sequence of connected vehicle (3.11) actions, events, reactions, and interactions, in a road
safety setting
3.3
time-constrained situation
combination of a road safety-related connected vehicle (3.11) scenario (3.2) and RExVeS-
related time constraints, in which lack of communication capability or excessive (communication)
latency can lead to malfunctions or other injurious consequences
3.4
safety-critical situation
combination of a road safety-related connected vehicle (3.11) scenario (3.2) and an
unacceptable risk of harm
3.5
situation priority class
one of six situation priority classes (P1, P2, P3, P4, P5 or P6) determined according to the
severity, the probability of exposure, and the controllability associated with an evaluated time-
constrained situation (3.3)
3.6
safety-critical situation priority class
one of the four situation priority classes (3.5) (P3, P4, P5 or P6) determined according to the
severity, the probability of exposure, and the controllability associated with an evaluated safety-critical
situation (3.4)
3.7
time-constrained safety-r
...