ISO 34501:2022

Road vehicles - Test scenarios for automated driving systems - Vocabulary

The document defines terms in the context of test scenarios for automated driving systems (ADS). The document is applicable to ADS of Level 3 and above defined in ISO/SAE PAS 22736.

Véhicules routiers — Scénarios d'essai pour les systèmes de conduite automatisée — Vocabulaire

General Information

• Status: Published
• Publication Date: 05-Oct-2022
• ICS: 01.040.43 - Road vehicle engineering (Vocabularies)
• ICS: 43.020 - Road vehicles in general
• Technical Committee: ISO/TC 22/SC 33 - Vehicle dynamics and chassis components
• Drafting Committee: ISO/TC 22/SC 33/WG 9 - Test scenarios of automated driving systems
• Current Stage: 6060 - International Standard published
• Start Date: 06-Oct-2022
• Due Date: 27-Oct-2022
• Completion Date: 06-Oct-2022

Overview

ISO 34501:2022, titled "Road Vehicles - Test Scenarios for Automated Driving Systems - Vocabulary," is a critical international standard developed by ISO Technical Committee ISO/TC 22, Subcommittee SC 33. This document defines precise terminology related to test scenarios for Automated Driving Systems (ADS), specifically for systems classified as Level 3 and above, according to ISO/SAE PAS 22736.

Automated Driving Systems encompass the hardware and software that enable vehicles to perform driving tasks with minimal or no human intervention. As ADS technology advances rapidly, standardizing the vocabulary used in test scenarios becomes essential for clear communication, regulatory compliance, and ensuring vehicle safety.

Key Topics

ISO 34501:2022 provides comprehensive definitions and explanations of terms crucial for understanding and developing test scenarios for ADS:

• Automated Driving System (ADS): Hardware and software capable of executing full dynamic driving tasks on a sustained basis, particularly Level 3 to Level 5 systems.
• Test Scenario: A sequence of scenes designed to assess ADS performance, including subject vehicles, actors, environmental conditions, and interactions.
• Scene and Situation: Snapshots of all relevant entities and the surrounding environment at specific moments within a scenario, described from actors' perspectives.
• Entities: Elements of interest which can be static (unchanging during the test) or dynamic (state-changing), including infrastructure, road users, and environmental features.
• Actors and Actions: Entities capable of interacting within a test scenario, including the behavior and activities they perform.
• Scenario Categorization: Different levels of scenario abstraction are defined - functional, abstract, logical, and concrete - to progressively increase detail and specificity.
• Operational Design Domain (ODD): Specifies the environmental and operational conditions under which the ADS is designed to function safely.

The vocabulary emphasizes clear distinctions among these terms, which are foundational for constructing, executing, and interpreting ADS test scenarios. The document recognizes the interrelation of these terms with other standards like ISO 21448 and ISO 26262-1 but focuses on their unique application in scenario-based testing.

Applications

The terminology defined in ISO 34501:2022 is vital for professionals and organizations involved in the design, testing, evaluation, and regulatory compliance of automated driving technologies. Its practical applications include:

• Development of Test Scenarios: Helps engineers and testers construct consistent, unambiguous test scenarios with clearly identified entities, triggers, actions, and expected behaviors.
• Safety Assessment: Assists in defining scenarios that accurately reflect realistic and edge-case driving conditions to ensure ADS reliability.
• Regulatory Frameworks: Facilitates government and industry collaboration by providing a shared language that supports legislation and certification processes for ADS technologies.
• Scenario-Based Engineering: Enables systematic documentation, communication, and analysis in the engineering lifecycle of automated vehicles.
• Standardization of Reporting: Promotes consistent reporting formats and terminology across projects and organizations, reducing misunderstandings and increasing efficiency.

By adopting the standardized vocabulary, stakeholders can better coordinate the integration of ADS features, test their performance under varied conditions, and meet safety and operational criteria effectively.

Related Standards

ISO 34501:2022 complements and interfaces with several key standards relevant to automated driving and functional safety:

• ISO/SAE PAS 22736: Defines levels of driving automation systems - foundational for understanding the scope of ADS in ISO 34501.
• ISO 21448: Focuses on safety of the intended functionality (SOTIF) and shares some terminologies related to scenarios and actors.
• ISO 26262-1: Addresses functional safety for road vehicles, especially electrical and electronic systems.
• ISO/IEC Directives, Part 1 & 2: Governs the editorial standards and procedures for ISO documents, ensuring consistency in terminology and document structure.
• PEGASUS Project: Influences scenario modeling approaches referenced in ISO 34501, particularly in defining scenario abstraction layers.

Together, these standards provide a comprehensive framework for the development, testing, and validation of advanced driving automation systems, reinforcing safety, reliability, and interoperability in the automotive industry.

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Keywords: ISO 34501:2022, Automated Driving Systems, ADS test scenarios, automated vehicle vocabulary, operational design domain, scenario-based testing, functional scenario, abstract scenario, logical scenario, concrete scenario, road vehicle automation, ADS safety testing, ADS regulatory standards.

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 34501
First edition
2022-10
Road vehicles — Test scenarios
for automated driving systems —
Vocabulary
Véhicules routiers — Scénarios d'essai pour les systèmes de conduite
automatisée — Vocabulaire
Reference number
© ISO 2022
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ii
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
Bibliography . 9
Index .10
iii
Foreword
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This document was prepared by Technical Committee ISO/TC 22, Road vehicles, Subcommittee SC 33,
Vehicle dynamics and chassis components.
Any feedback or questions on this document should be directed to the user’s national standards body. A
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iv
Introduction
Automated driving systems (ADS) combine a variety of sensors to perceive their surroundings, such as
cameras, radars, lidars, sonars, GNSS receivers, HD maps, odometry and inertial measurement units.
ADS advanced control systems interpret sensory information to identify appropriate navigation paths,
as well as obstacles and relevant signage and automatically control the vehicle. To make this work, the
vehicle is developed by simulation and real-world operation to ensure the driving capacities of the ADS,
with the priority being safety. Prior to releasing to the public, the system is tested for many scenarios
from varieties of sources, not limited to naturalistic driving situations and known corner cases.
Scenario-based test methods for ADS mainly consist of four aspects: test scenarios, procedures,
equipment and criteria with which the performance of ADS can be evaluated. Among these aspects,
the development of test scenarios is most fundamental since their integrity and representativeness are
crucial for evaluating the performance of ADS. Test scenarios serve as a basis for developing relevant
procedures, equipment and criteria. Because of the importance of the test scenarios, the needs for
standardizing the language we use to describe scenarios are derived from the demand of government
and industry in terms of performing ADS design, testing, evaluation, and management, etc.
A universal norm of vocabularies supports providing basic ideas and clarifying the interrelations and
concepts commonly used in scenarios. These vocabularies could be useful to facilitate the mutual-
understanding, communication, and development of scenario-based engineering process.
In the context of automated driving, the vocabulary of test scenario is inevitably associated with
existing standards like ISO 21448, ISO 26262-1 or other technical documents. However, people may find
that some terms being defined in this document might not be identical with those in other documents.
That is because, terms in this document are defined and interpreted in the context of test scenarios
description with emphasis on their interrelationship to each other, while other standards may focus on
safety or other aspects.
v
INTERNATIONAL STANDARD ISO 34501:2022(E)
Road vehicles — Test scenarios for automated driving
systems — Vocabulary
1 Scope
The document defines terms in the context of test scenarios for automated driving systems (ADS).
The document is applicable to ADS of Level 3 and above defined in ISO/SAE PAS 22736.
2 Normative references
There are no normative references in this document.
3 Terms and definitions
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
automated driving system
ADS
hardware and software that are collectively capable of performing the entire dynamic driving task
(DDT) (3.27) on a sustained basis, regardless of whether it is limited to a specific operational design
domain (ODD) (3.26)
Note 1 to entry: ADS is used specifically to describe a Level 3, 4, or 5 driving automation system.
Note 2 to entry: In contrast to ADS, the generic term “driving automation system” refers to any Level 1 to 5
system or feature that performs part or all of the DDT on a sustained basis. Given the similarity between the
generic term, “driving automation system” and the Level 3 to 5 specific term, “automated driving system”, the
latter term should be capitalized when spelled out and reduced to its abbreviation, ADS, as much as possible,
while the former term should not be.
[SOURCE: ISO/SAE PAS 22736: 2021, 3.2, modified — Note 1 to entry has been added.]
3.2
system under test
SUT
automated driving system (ADS) (3.1) that is tested with test scenarios (3.5)
3.3
subject vehicle
ego vehicle
host vehicle
vehicle under observation in the process of testing, evaluation, or demonstration
Note 1 to entry: Subject-vehicle testing can be connected with automated driving system (ADS) (3.1) testing. In
certain cases, the ADS can be tested via vehicle testing. Under these circumstances, the performance of the vehicle
does not differ from the performance of the ADS. This is not applicable to the tests that involve the interaction
between the ADS and the user.
3.4
scenario
sequence of scenes (3.6) usually including the automated driving system(s) (ADS) (3.1)/subject vehicle(s)
(3.3), and its/their interactions in the process of performing the dynamic driving task (DDT) (3.27)
Note 1 to entry: The definition is an editorial rework of the definition in ISO 21448. The intended meaning of both
definitions is the same.
EXAMPLE In the scenario in Figure 1, there are two actors (3.16), actor 1 is the subject vehicle, actor 2 is the
pedestrian who is about to cross the street. The purpose of this scenario is to specify the behaviour of the subject
vehicle (actor 1) in response to the given actions (3.15) of the pedestrian (actor 2). There are two 2 triggers (3.14)
in this scenario. The initiation of the scenario is indicated by trigger 1, which corresponds to the moment that
the pedestrian starts crossing the street. At the same time, the subject vehicle is traveling at a pre-set speed
for the test purpose. In this case, the scene of a pedestrian appearing on the street becomes the situation (3.17)
from the perspective of the subject vehicle. The expected behaviour of the subject vehicle under ADS control is to
decelerate to stop until the pedestrian safely finishes crossing the road. The event (3.13) of a pedestrian arriving
at the opposite roadside could be the trigger 2 for t
...