ISO/FDIS 23792-2
(Main)Intelligent transport systems — Motorway chauffeur systems (MCS) — Part 2: Requirements and test procedures for discretionary lane change
Intelligent transport systems — Motorway chauffeur systems (MCS) — Part 2: Requirements and test procedures for discretionary lane change
Motorway Chauffeur Systems (MCS) performs level 3 automated driving [1] on limited access motorways with the presence of a fallback-ready user (FRU). MCS will be implemented in various forms capable of responding to different driving scenarios. This document specifies the requirements and test procedure to verify the requirements for the discretionary lane change functionality (DLC). The DLC is an additional functionality that a MCS compliant to the general requirements specified in ISO 23792-1 can be equipped with. When conditions are satisfied, a DLC equipped MCS performs the entire DDT to change the current lane of travel even though it is still possible to continue operation within its current lane of travel. The system monitors the driving environment in the adjacent lanes and operates the SV by adjusting the speed and lateral position to move the SV to the intended lane. MCS may delay the manoeuvre until the conditions for initiating the lane change are satisfied or cancel the lane change when conditions are not satisfied. Activation of the DLC requires an engaged MCS performing in-lane driving. Means related to setting a destination and selecting a route to reach the destination are not in the scope of this document. This document applies to the system installed in light vehicles [2]. Reference; [1] ISO/SAE PAS 22736, Intelligent transport systems -- Taxonomy and definitions for terms related to driving automation systems for on-road motor vehicles [2] International Organization of Motor Vehicle Manufacturers, Vehicle type definitions http://www.oica.net/production-statistics/
Systèmes de transport intelligents — Systèmes de conduite automatisée sur voie à chaussée séparée (MCS) — Partie 2: Exigences et procédures d'essai pour le changement de voie
General Information
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Standards Content (Sample)
FINAL DRAFT
International
Standard
ISO/TC 204
Intelligent transport systems —
Secretariat: ANSI
Motorway chauffeur systems
Voting begins on:
(MCS) —
2025-12-18
Part 2:
Voting terminates on:
2026-02-12
Requirements and test procedures
for discretionary lane change
Systèmes de transport intelligents — Systèmes de conduite
automatisée sur voie à chaussée séparée (MCS) —
Partie 2: Exigences et procédures d'essai pour le changement de
voie
RECIPIENTS OF THIS DRAFT ARE INVITED TO SUBMIT,
WITH THEIR COMMENTS, NOTIFICATION OF ANY
RELEVANT PATENT RIGHTS OF WHICH THEY ARE AWARE
AND TO PROVIDE SUPPOR TING DOCUMENTATION.
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BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO-
LOGICAL, COMMERCIAL AND USER PURPOSES, DRAFT
INTERNATIONAL STANDARDS MAY ON OCCASION HAVE
TO BE CONSIDERED IN THE LIGHT OF THEIR POTENTIAL
TO BECOME STAN DARDS TO WHICH REFERENCE MAY BE
MADE IN NATIONAL REGULATIONS.
Reference number
FINAL DRAFT
International
Standard
ISO/TC 204
Intelligent transport systems —
Secretariat: ANSI
Motorway chauffeur systems
Voting begins on:
(MCS) —
Part 2:
Voting terminates on:
Requirements and test procedures
for discretionary lane change
Systèmes de transport intelligents — Systèmes de conduite
automatisée sur voie à chaussée séparée (MCS) —
Partie 2: Exigences et procédures d'essai pour le changement de
voie
RECIPIENTS OF THIS DRAFT ARE INVITED TO SUBMIT,
WITH THEIR COMMENTS, NOTIFICATION OF ANY
RELEVANT PATENT RIGHTS OF WHICH THEY ARE AWARE
AND TO PROVIDE SUPPOR TING DOCUMENTATION.
© ISO 2025
IN ADDITION TO THEIR EVALUATION AS
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO-
LOGICAL, COMMERCIAL AND USER PURPOSES, DRAFT
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
INTERNATIONAL STANDARDS MAY ON OCCASION HAVE
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
TO BE CONSIDERED IN THE LIGHT OF THEIR POTENTIAL
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Published in Switzerland Reference number
ii
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Symbols and abbreviated terms. 2
5 Motorway chauffer systems (MCS) with discretionary lane change (DLC) . 5
5.1 DLC functionality .5
5.2 Lane change procedure . .5
6 Requirements . 6
6.1 General .6
6.2 State transitions .6
6.2.1 The states of DLC .7
6.2.2 The states of MCS .7
6.2.3 Transitions between the states .8
6.3 Detection function . .9
6.3.1 Detection of a sufficient gap and target lane availability .9
6.4 Driver interface . 13
6.4.1 Internal display elements . 13
6.4.2 External notifications . 13
6.4.3 Fallback ready user (FRU) input . 13
6.4.4 DLC manoeuvre .14
6.4.5 Failure reactions .14
7 Minimum performance . 14
7.1 Duration of the lane change manoeuvre .14
7.2 Operational limit . 15
8 Performance evaluation test methods .15
8.1 Environment conditions. 15
8.2 Test course conditions . 15
8.3 Test vehicle conditions . 15
8.4 Test system installation and configuration .16
8.5 Test procedures .16
8.5.1 Normal operation.16
8.5.2 Response to MCS cancellation condition during DLC .17
8.5.3 DLC conditions not met before starting the lane change procedure (Phase 1).17
8.5.4 DLC conditions not met after starting the lane change procedure (start of Phase
2) .18
8.5.5 Steering input during DLC .18
Annex A (informative) Permitted velocity for conducting a lane change . 19
Bibiography . .21
iii
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out through
ISO technical committees. Each member body interested in a subject for which a technical committee
has been established has the right to be represented on that committee. International organizations,
governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely
with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are described
in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types
of ISO document should be noted. This document was drafted in accordance with the editorial rules of the
ISO/IEC Directives, Part 2 (see www.iso.org/directives).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent
rights in respect thereof. As of the date of publication of this document, ISO had not received notice of (a)
patent(s) which may be required to implement this document. However, implementers are cautioned that
this may not represent the latest information, which may be obtained from the patent database available at
www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and expressions
related to conformity assessment, as well as information about ISO's adherence to the World Trade
Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 204, Intelligent transport systems.
A list of all parts in the ISO 23792 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
iv
Introduction
In order to operate a vehicle automatically on motorways, it is necessary for the automated driving system
(ADS) to be designed with the capability to cope with various conditions such as the driving environment,
status of other vehicles in the surroundings, traffic regulations, etc.
In addition, an ADS designed to operate on motorways can encounter various situations such as merging
into the main lane of traffic, adjusting the speed according to congested or freely flowing traffic, overtaking
other vehicles, or changing lanes when approaching an exit or lane closure.
For Level 3 automated driving, the ADS issues a request to the fallback-ready user (FRU) to take over driving
tasks when it cannot respond to certain conditions and situations.
The ISO 23793 series identifies the performance requirements of an ADS based on its capability to respond
to various conditions and situations. The requirements are derived in order to reliably transfer the vehicle
operation between the human driver and ADS, and for the safe operation by the ADS.
This series focuses on the system functionalities, keeping in mind that the FRU is assumed to be receptive
and properly responding to system requests to take over driving tasks, which is a prerequisite condition for
the use of Level 3 driving automation.
This document focuses on discretionary lane change (DLC) for motorway chauffeur systems (MCS). When
conditions are satisfied, a DLC equipped MCS performs the entire DDT to change the current lane of travel
independently of the possibility of continuing operation within its current lane of travel. The system
monitors the driving environment in the adjacent lanes and operates the SV by adjusting the speed and
lateral position to move the SV to the intended lane. The MCS can delay the manoeuvre until the conditions
for initiating the lane change are satisfied or can cancel the lane change when conditions are not satisfied.
Activation of the DLC requires an engaged MCS performing in-lane driving.
v
FINAL DRAFT International Standard ISO/FDIS 23792-2:2025(en)
Intelligent transport systems — Motorway chauffeur systems
(MCS) —
Part 2:
Requirements and test procedures for discretionary lane
change
1 Scope
This document specifies the requirements for discretionary lane change (DLC) for motorway chauffeur
[1]
systems (MCS) that perform Level 3 automated driving on limited access motorways. It also specifies the
test procedures to verify the requirements. DLC is an additional functionality that can be added to an MCS
compliant with the general requirements specified in ISO/TS 23792-1.
Means related to setting a destination and selecting a route to reach the destination are not in the scope of
this document.
[2]
This document applies to the system installed in light vehicles.
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/TS 23792-1, Intelligent transport systems — Motorway chauffeur systems (MCS) — Part 1: Framework and
general requirements
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
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
subject vehicle
SV
vehicle equipped with the system in question and related to the topic of discussion
3.2
lane
strip of road intended to accommodate a single line of moving vehicles, frequently defined by visible lane
marking (3.6)
3.3
initial lane
lane (3.2) in which the subject vehicle (3.1) is driving before starting the lane change manoeuvre (3.7)
Note 1 to entry: See Figure 2 for a description of lanes and vehicles.
3.4
target lane
lane (3.2) next to the initial lane (3.3), which the subject vehicle (3.1) targets to make a lane change
Note 1 to entry: See Figure 2 for a description of lanes and vehicles.
3.5
adjacent to target lane
lane (3.2) next to the target lane (3.4), which the subject vehicle (3.1) targets to make a lane change
3.6
lane marking
delineators or markings intentionally placed on the borderline of the lane (3.2)
EXAMPLE Botts' dots.
3.7
lane change manoeuvre
addition of a lateral movement to the current longitudinal motion of the subject vehicle (3.1), which the
system automatically executes with the sole purpose of changing lanes (3.2) from its initial lane (3.3) to an
adjacent lane with the same direction of travel
3.8
time gap
t
gap
value calculated from vehicle speed, v, and clearance, c
Note 1 to entry: The time gap is calculated using Formula (1):
t = c/v (1)
gap
Note 2 to entry: to entry: If the subject vehicle (3.1) is one of vehicles for which the time gap is being calculated, as in
Figure 1, the subject vehicle speed should be taken as the value for v.
Key
c clearance
v vehicle speed
Figure 1 — Time gap
3.9
gap search
function of searching for a sufficient gap to make a lane (3.2) change into the target lane (3.4)
4 Symbols and abbreviated terms
For the purposes of this document, the abbreviated terms listed in Table 1 and the symbols listed in Table 2
apply.
Table 1 — Abbreviated terms
Abbreviated terms Definition
ADS automated driving system
adjacent to target lane following vehicle, i.e. immediate following vehicle in the adjacent
AFV
to target lane before starting a lane change manoeuvre
adjacent to target lane leading vehicle, i.e. immediate leading vehicle in the adjacent to
ALV
target lane before starting a lane change manoeuvre
DDT dynamic driving task
DLC discretionary lane change
FRU fallback-ready user
initial lane following vehicle, i.e. immediate following vehicle in the initial lane before
IFV
starting a lane change manoeuvre
initial lane leading vehicle, i.e. immediate leading vehicle in the initial lane before starting
ILV
a lane change manoeuvre
MCS motorway chauffeur systems
ODD operational design domain
RTI request to intervene
SV subject vehicle
target lane following vehicle, i.e. immediate following vehicle in the target lane before
TFV
starting a lane change manoeuvre
target lane leading vehicle, i.e. immediate leading vehicle in the target lane before starting
TLV
a lane change manoeuvre
Table 2 — Symbols
Symbols Definition
a maximum lateral acceleration the subject vehicle may generate during the DLC
Lat_max
a maximum lateral jerk that the subject vehicle may generate during the DLC
Lat_Jerk_max
c clearance
necessary deceleration to be generated by the SV for the v to become equivalent to v
SV TLV
d
SV
and to maintain the required distance between the TLV and the SV at steady state
d deceleration assumed to be performed by the TFV
TFV
d deceleration assumed to be performed by the TLV
TLV
required distance between the SV and the TLV assumed to be remaining at the end of the
D
SV_TLV
lane change
minimum distance to be maintained between the SV and the TLV at low speed, based on
D
SV_TLVmin
a predetermined distance limit
relative distance between the TFV and the SV that would shorten while TFV decelerates
D
TFVdec
at an assumed level (d )
TFV
required distance between the TFV and the SV assumed to be remaining at the end of
D
TFV_SV
the lane change
minimum distance to be maintained between the TFV and the SV at low speed, based on
D
TFV_SVmin
a predetermined distance limit
D detection range required to detect the distance between the SV and the TFV
TFVrange
relative distance between the TFV and the SV that would shorten while TFV is assumed
D
TFVreact
to react (t ) to start decelerating
TFVreact
required distance to be detected between the TFV and the SV to determine a sufficient
D
TFVreq
gap for executing a lane change
relative distance between the TLV and the SV that would shorten while TLV decelerates
D
TLVdec
at an assumed level (d )
TLV
TTabablele 2 2 ((ccoonnttiinnueuedd))
Symbols Definition
relative distance between the TLV and the SV that would shorten while TLV is assumed
D
TLVreact
to react (t ) to start decelerating
TLVreact
required distance to be detected between the TLV and the SV to determine a sufficient
D
TLVreq
gap for executing a lane change
t time gap
gap
t time gap between the SV and the TLV
gapSV_TLV
t time gap between the TFV and the SV
gapTFV_SV
reaction time of the SV to start deceleration after the SV starts a lane change manoeuvre
t
SVreact
towards the target lane
assumed reaction time of the TFV to start the deceleration, after the SV starts a lane
t
TFVreact
change manoeuvre towards the target lane
assumed reaction time of the TLV to start the deceleration, after the SV starts a lane change
t
TLVreact
manoeuvre towards the target lane
v vehicle speed
v speed limit of the motorway
limit
v current velocity of the SV as observed in real time
SV
v velocity of the following vehicle approaching in the target lane
TFV
v velocity of the leading vehicle in the target lane
TLV
Figure 2 provides a description of the lanes and vehicles associated with the lane change. See Table 1 for the
relevant abbreviated terms.
Key
1 IFV
2 SV
3 ILV
4 TLV
5 ALV
6 AFV
7 TFV
a
Initial lane.
b
Target lane.
c
Adjacent to target lane.
Figure 2 — Description of lanes and vehicles
5 Motorway chauffer systems (MCS) with discretionary lane change (DLC)
5.1 DLC functionality
A DLC-functionality-equipped MCS (hereafter referred to as a “system”) performs the entire dynamic driving
task (DDT) for lane changes when a manufacturer-defined motivation for lane change exists. Motivation for
a lane change is based upon conditions designed for the system. Examples of possible discretionary lane
change motivations can be:
a) FRU makes an input to request a lane change;
b) to follow the lane of travel to keep the planned route;
c) to overtake the ILV.
5.2 Lane change procedure
The DLC is executed through the following phases. Figure 3 illustrates the position of the SV at the start of
each phase.
Figure 3 — Phases of DLC
— Phase 0: Lane change functionality is idle and is in the standby state (refer to 6.2.1.3). Motivation for lane
change does not exist.
— Phase 1: Motivation for a lane change exists. The system executes the gap search.
— Phase 2: start of a lane change procedure. The system will notify the FRU of the start of the procedure.
The procedure is indicated to surrounding vehicles with the turn indicator. It is up to the manufacturer
to determine how the lane change procedure is cancelled if the lane change manoeuvre cannot be started
within a certain time period.
— Phase 3: The sufficient gap conditions have been confirmed and lane change manoeuvre has started and
DLC is in the active state (refer to 6.2.1.4), but the SV has not yet left the initial lane. The SV leaves the
initial lane after the turn signal is indicated for the specified period of time (refer to 6.2.1.4).
— Phase 4: The system is performing a lane change and the SV has entered the target lane with at least one
tyre in contact with the lane marking (refer to 6.2.1.4).
— Phase 5: The SV has almost finished performing the lane change (point of no return), i.e. the manoeuvre
has reached a sufficient point for it to be considered that the target lane is now the travel lane. The lane
change manoeuvre may therefore be completed even though a new vehicle is detected to be approaching
from behind, within the area of the sufficient gap. The SV should be positioned with at least half the
lateral position at the front tyres within the target lane, but not completely within the target lane.
— Phase 6: The SV has finished performing the lane change and all tyres are completely within the target
lane. The lane change manoeuvre is therefore completed and the DLC returns to the standby state (refer
to 6.2.1.3). Lane centring may be performed separately in order to position the vehicle within the target
lane.
6 Requirements
6.1 General
The system performs the lane change manoeuvre with the existence of a FRU. The system shall have
detection, driver interface, manoeuvring and failure reaction functions as described in this clause (see also
6.4.5).
6.2 State transitions
The system shall, at a minimum, provide the operations and state transitions described in Figure 4.
Key
DL1 DLC turned on
DL2 DLC conditions to start manoeuvre are satisfied
DL3 DLC manoeuvre completed
DL4 DLC turned off
M1 MCS turned on
M2 Engagement conditions are satisfied
M3 FRU override
M5 Disengagement-triggering condition detected
M6 FRU override
M7 MCS turned off
M8 MCS turned off
Figure 4 — DLC state diagram
6.2.1 The states of DLC
6.2.1.1 DLC off
DLC functions are not performed in the DLC off state. DLC is turned off or a failure of DLC is detected.
6.2.1.2 DLC on
DLC can automatically transition to DLC on upon entering MCS normal state, thus entering DLC standby, in
case MCS is engaged. It is also allowed that the DLC first starts from DLC off in case MCS is engaged.
6.2.1.3 DLC standby (Phases 0 – 2 and 6)
The system evaluates the conditions to perform a lane change using information on surroundings which is
obtained from sensors installed on the vehicle. This state corresponds to Phase 0 – Phase 2 and Phase 6 of
the lane change procedure (see Figure 3).
6.2.1.4 DLC Active (Phases 3 – 5)
The DLC manoeuvre is performed. This state corresponds to Phase 3 – Phase 5 of the lane change procedure
(see Figure 3). No SV tyre shall touch the lane marker earlier than 3 s after activation of the turn signal. The
gap confirmation shall continue throughout the lane change manoeuvre until reaching the point of no return
defined in Phase 5. Once at least one tyre of the SV is in contact with and crosses the lane marking (Phase 4),
the manoeuvre shall be executed with a single lateral velocity peak, unless a cancellation condition or
insufficient gap condition has been detected.
6.2.2 The states of MCS
6.2.2.1 MCS off
In the off state, the MCS including the DLC functionality is turned off. Monitoring functions can be active in
order to detect conditions that influence transitions.
6.2.2.2 MCS standby
In addition to the conditions required in ISO/TS 23792-1, the system shall determine if engagement conditions
are satisfied by continuously monitoring, at a minimum, the conditions of the driving environment, MCS and
SV that are relevant for DLC.
6.2.2.3 MCS requesting fallback during lane change manoeuvre
In the requesting fallback state, the system shall have the following means:
— extend its operation of the lane change procedure and continue to perform the DDT for a sufficient length
of time for the FRU to perform the fallback, unless the transition condition M6 or M7 in Figure 4, as
defined in ISO/TS 23792-1, is satisfied;
— whilst performing the DDT, prioritize keeping distance from surrounding vehicles and if possible, bring
the SV fully into either the initial or the target lane.
In the requesting fallback state, in case the FRU does not respond adequately to the request to intervene
(RTI), the system should in addition:
— perform a minimal risk manoeuvre (MRM) by manoeuvring the SV into either the initial or target lane
and if capable, either define and manoeuvre to a stopping location or reach minimal risk condition
(MRC), or both, prioritizing maintaining distance from the detected obstacles including the vehicles in
the initial, target and adjacent lanes before bringing the SV to a complete stop.
6.2.2.4 MCS normal
In the normal state, where DLC function is activated, the system shall:
— perform the entire DDT in accordance with the minimum DDT performance requirements of those for
DLC;
— detect the occurrence of disengagement-triggering conditions and direct disengagement conditions by
continuously monitoring, at a minimum, conditions of the driving environment, MCS system, and SV,
which apply to DLC.
6.2.3 Transitions between the states
The transitions b
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ISO/DIS FDIS 23792-2:2025(en) .
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Intelligent transport systems — Motorway chauffeur
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ISO/DIS 23792-2:2025(en)
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Contents
Adjust space between Asian text and numbers
Foreword . v
Introduction. vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions. 1
4 Symbols and abbreviated terms . 3
5 Motorway chauffer systems (MCS) with discretionary lane change (DLC) . 7
5.1 DLC functionality . 7
5.2 Lane change procedure . 7
6 Requirements . 8
6.1 General . 8
6.2 State transitions . 8
6.3 Detection function . 13
6.4 Driver interface . 18
7 Minimum performance . 20
7.1 Duration of the lane change manoeuvre . 20
7.2 Operational limit . 20
8 Performance evaluation test methods . 20
8.1 Environment conditions . 20
8.2 Test course conditions. 21
8.3 Test vehicle conditions . 21
8.4 Test system installation and configuration . 21
8.5 Test procedures . 21
Annex A (informative) Permitted velocity for conducting a lane change . 26
Bibiography . 28
Foreword . iv
Introduction. v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions. 1
3.1 subject vehicle (SV) . 1
3.2 lane . 1
3.3 initial lane . 2
3.4 target lane . 2
3.5 adjacent to target lane . 2
3.6 lane marking . 2
3.7 lane change manoeuvre . 2
3.8 time gap. 2
3.9 gap search . 2
4 Symbols and abbreviated terms . 2
iii
5 Motorway chauffer systems (MCS) with discretionary lane change (DLC) . 4
5.1 DLC functionality . 4
5.2 The lane change procedure . 4
6 Requirements . 5
6.1 General . 5
6.2 State transitions . 5
6.2.1 The states of DLC. 6
6.2.2 The states of MCS . 7
6.2.3 Transitions between the states . 8
6.3 Detection function . 9
6.3.1 Detection of a sufficient gap and target lane availability . 9
6.4 Driver interface . 12
6.4.1 Internal Display elements . 12
6.4.2 External notifications . 13
6.4.3 Fallback ready user (FRU) input . 13
6.4.4 DLC manoeuvre . 13
6.4.5 Failure reactions . 14
7 Minimum performance . 14
7.1 Duration of the lane change manoeuvre . 14
7.2 Operational Limit . 14
8 Performance evaluation test methods . 15
8.1 Environment conditions . 15
8.2 Test course conditions. 15
8.3 Test vehicle conditions . 15
8.4 Test system installation and configuration . 15
8.5 Test procedures . 15
8.5.1 Normal operation . 15
8.5.2 Response to MCS cancellation condition during DLC . 17
8.5.3 DLC conditions not met before starting the lane change procedure (Phase1) . 17
8.5.4 DLC conditions not met after starting the lane change procedure (Start of Phase2) . 17
8.5.5 Steering input during DLC . 18
9 Bibliography . 20
ISO/DIS 23792-2:2025(en)
Formatted: Adjust space between Latin and Asian text,
Foreword
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ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO
collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO document should be noted. This document was drafted in accordance with the
English (United Kingdom)
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives). Formatted:
ISO draws attention to the possibility that the implementation of this document may involve the use of
(a) patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed
patent rights in respect thereof. As of the date of publication of this document, ISO had not received notice
of (a) patent(s) which may be required to implement this document. However, implementers are
cautioned that this may not represent the latest information, which may be obtained from the patent
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identifying any or all such patent rights.
Any trade name used in this document is information given for the convenience of users and does not
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For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the World
Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see
English (United Kingdom)
www.iso.org/iso/foreword.htmlwww.iso.org/iso/foreword.html. Formatted:
This document was prepared by Technical Committee ISO/TC 204, Intelligent transport systems. Formatted: Font: Italic
A list of all parts in the ISO 23792 series can be found on the ISO website.
English (United Kingdom)
Any feedback or questions on this document should be directed to the user’s national standards body. A Formatted:
complete listing of these bodies can be found at www.iso.org/members.html.
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Formatted: English (United Kingdom)
Field Code Changed
v
Introduction
In order to operate a vehicle automatically on motorways, it is necessary for the automated driving
system (ADS) mustto be designed with the capability to cope with various conditions such as the driving
environment, status of other vehicles in the surroundings, traffic regulations, etc.
In addition, an ADS designed to operate on motorways can encounter various situations such as merging
into the main lane of traffic, adjusting the speed according to congested or freely flowing traffic,
overtaking other vehicles, or changing lanes when approaching an exit or lane closure.
For Level 3 automated driving, the ADS issues a request to the fallback-ready user (FRU) to take over
driving tasks when it cannot respond to certain conditions and situations.
The ISO 23793 series identifies the performance requirements of an ADS based on its capability to
respond to various conditions and situations. The requirements are derived in order to reliably transfer
the vehicle operation between the human driver and ADS, and for the safe operation by the ADS.
This series focuses on the system functionalities, keeping in mind that the FRU is assumed to be receptive
and properly responding to system requests to take over driving tasks, which is a prerequisite condition
for the use of Level 3 driving automation.
Motorway chauffer systems (MCS) – Part2: This document focuses on discretionary lane change (DLC) for
motorway chauffeur systems (MCS). When conditions are satisfied, a DLC equipped MCS performs the entire
DDT to change the current lane of travel independently of the possibility of continuing operation within its
current lane of travel. The system monitors the driving environment in the adjacent lanes and operates the SV
by adjusting the speed and lateral position to move the SV to the intended lane. The MCS can delay the
manoeuvre until the conditions for initiating the lane change are satisfied or can cancel the lane change when
conditions are not satisfied. Activation of the DLC requires an engaged MCS performing in-lane driving.
vii
DRAFT International Standard ISO/DIS 23792-2:2025(en)
Intelligent transport systems — Motorway chauffeur systems
(MCS) —
Formatted: Main Title 2, Adjust space between Latin
Part 2:
and Asian text, Adjust space between Asian text and
numbers
Requirements and test procedures for discretionary lane change
1 Scope
This document specifies the requirements for discretionary lane change (DLC) for Motorway Chauffeur
[1][1]
Systemsmotorway chauffeur systems (MCS) that perform Level 3 automated driving on limited access
motorways and. It also specifies the test procedures to verify the requirements. The DLC is an additional
functionality that can be added to an MCS compliant with the general requirements specified in ISO/TS 23792- Formatted: Default Paragraph Font
1.
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Formatted:
When conditions are satisfied, a DLC equipped MCS perform the entire DDT to change the current lane of travel
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independent of the possibility to continue operation within its current lane of travel. The system monitors the
driving environment in the adjacent lanes and operates the SV by adjusting the speed and lateral position to
move the SV to the intended lane. MCS may delay the manoeuvre until the conditions for initiating the lane
change are satisfied or cancel the lane change when conditions are not satisfied.
Activation of the DLC requires an engaged MCS performing in-lane driving. Means related to setting a Formatted: Adjust space between Latin and Asian
text, Adjust space between Asian text and numbers
destination and selecting a route to reach the destination are not in the scope of this document. This document
applies to the system installed in light vehicles [2].
[2]
This document applies to the system installed in light vehicles.
2 Normative references Formatted: Adjust space between Latin and Asian
text, Adjust space between Asian text and numbers
Default Paragraph Font
The following documents are referred to in the text in such a way that some or all of their content constitutes Formatted:
requirements of this document. For dated references, only the edition cited applies. For undated references,
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the latest edition of the referenced document (including any amendments) applies.
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ISO/TS 23792--1, Intelligent transport systems — Motorway chauffeur systems (MCS) — Part 1: Framework
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Formatted:
and general requirements
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Formatted:
text, Adjust space between Asian text and numbers,
3 Terms and definitions
Tab stops: Not at 0.7 cm + 1.4 cm + 2.1 cm + 2.8 cm
+ 3.5 cm + 4.2 cm + 4.9 cm + 5.6 cm + 6.3 cm + 7
For the purposes of this document, the following terms and definitions apply.
Adjust space between Latin and Asian
Formatted:
text, Adjust space between Asian text and numbers
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
Formatted: English (United Kingdom)
Formatted: Font: 11 pt, English (United Kingdom)
— — ISO Online browsing platform: available at https://www.iso.org/obphttps://www.iso.org/obp
English (United Kingdom)
Formatted:
— — IEC Electropedia: available at https://www.electropedia.org/https://www.electropedia.org/
Formatted: English (United Kingdom)
Formatted: TermNum2, Adjust space between Latin
3.1 3.1
and Asian text, Adjust space between Asian text and
subject vehicle
numbers
SV
Footer, Left, Space After: 0 pt, Line
Formatted:
vehicle equipped with the system in question and related to the topic of discussion
spacing: single, Tab stops: Not at 17.2 cm
HeaderCentered
Formatted:
3.2 3.2
lane
strip of road intended to accommodate a single line of moving vehicles, frequently defined by visible lane Formatted: Font: Italic
marking (3.6)
3.3 3.3
initial lane
lane (3.2) in which the subject vehicle (3.1)(3.1) is driving before starting the lane change manoeuvre (3.7) Formatted: Font: Italic
Formatted: Font: Not Italic
Note 1 to entry: See Figure 2Figure 2 for a description of lanes and vehicles.
Formatted: Font: Italic
Default Paragraph Font
Formatted:
3.4 3.4
target lane
Font: Italic
lane (3.2) next to the initial lane (3.3),(3.3), which the subject vehicle (3.1) targets to make a lane change Formatted:
Formatted: Font: Italic
Note 1 to entry: See Figure 2Figure 2 for a description of lanes and vehicles.
Formatted: Default Paragraph Font
3.5 3.5
adjacent to target lane
the lane (3.2) next to the target lane (3.4),(3.4), which the subject vehicle (3.1)(3.1) targets to make a lane Font: Italic
Formatted:
change
3.6 3.6
lane marking
delineators, or markings, or Botts’ dots intentionally placed on the borderline of the lane (3.2) Formatted: Font: Italic
3.7EXAMPLE Botts' dots.
3.7
Formatted: TermNum2, Adjust space between Latin
and Asian text, Adjust space between Asian text and
lane change manoeuvre
numbers
the addition of a lateral movement to the current longitudinal motion of the subject vehicle, (3.1), which the
Font: Italic
Formatted:
system automatically executes with the sole purpose of changing lanes (3.2) from its initial lane (3.3) to an
adjacent lane with the same direction of travel Formatted: Font: Italic
Formatted: Font: Italic
3.8 3.8
time gap
t
gap
value calculated from vehicle speed, v, and clearance, c by:
Note 1 to entry: The time gap is calculated using Formula (1):
t = c/v. In case (1)
gap
Note 2 to entry: to entry: If the subject vehicle (3.1)(3.1) is one of vehicles offor which the time gap is being calculated, as Note, Adjust space between Latin and
Formatted:
in the below Figure 1,Figure 1, the subject vehicle (3.1) speed should be taken as v, in generalthe value for v. Asian text, Adjust space between Asian text and
numbers
Formatted: Font: Not Italic
Formatted: FooterPageNumber
ISO/DIS FDIS 23792-2:2025(en) Formatted: Font: Bold, English (United Kingdom)
Font: Bold, English (United Kingdom)
Formatted:
Formatted: Font: Bold
Formatted: HeaderCentered, Left
Figure 1 — The time gap
Formatted: Adjust space between Latin and Asian
3.9
text, Adjust space between Asian text and numbers
Formatted: Font: Italic
Formatted: Default Paragraph Font, Font: 11 pt, Not
Bold, English (United Kingdom)
None, Adjust space between Latin and
Formatted:
Asian text, Adjust space between Asian text and
Key
numbers
c clearance
Formatted: Font: Not Bold
v vehicle speed
Adjust space between Latin and Asian
Formatted:
text, Adjust space between Asian text and numbers
Figure 1 — Time gap
Formatted Table
Formatted: Font: Not Bold
3.9
Formatted: Left, Adjust space between Latin and
gap search
Asian text, Adjust space between Asian text and
function to searchof searching for a sufficient gap to make a lane (3.2) change into the target lane (3.4)(3.4)
Formatted: Adjust space between Latin and Asian
text, Adjust space between Asian text and numbers
4 Symbols and abbreviated terms
Formatted Table
Left, Adjust space between Latin and
Formatted:
For the purposes of this document, the symbols and abbreviated terms listed in Table 1Table 1 and the
Asian text, Adjust space between Asian text and
symbols listed in Table 2 apply.
Formatted: Adjust space between Latin and Asian
text, Adjust space between Asian text and numbers
Table 1 — Abbreviated terms
Left, Adjust space between Latin and
Formatted:
Asian text, Adjust space between Asian text and
Symbols and MeaningDefinition
Formatted: Font: Not Italic
abbreviatedAbbreviated
terms
Formatted: Adjust space between Latin and Asian
text, Adjust space between Asian text and numbers
ADS automated driving system
Left, Adjust space between Latin and
Formatted:
adjacent to target lane following vehicle, i.e. immediate following vehicle in the Asian text, Adjust space between Asian text and
AFV adjacent to target lanelane next to the target lane before starting a lane change
Formatted: Font: Not Italic
manoeuvre
Formatted: Adjust space between Latin and Asian
adjacent to target lane leading vehicle, i.e. immediate leading vehicle in the adjacent to text, Adjust space between Asian text and numbers,
ALV
Tab stops: Not at 1.87 cm + 3.74 cm
target lanelane next to the target lane before starting a lane change manoeuvre
Formatted Table
the deceleration SV requires to generate for the v_SV to become equivalant tomatch
Formatted: Left, Adjust space between Latin and
dSVDDT v_TLV and to maintain the required distance between the TLV and SV at steady
Asian text, Adjust space between Asian text and
statedynamic driving task
Formatted: Font: Not Italic
dTFV deceleration that is assumed to be performed by the TFV
Formatted: Adjust space between Latin and Asian
text, Adjust space between Asian text and numbers,
distance between the SV and TLV required and assumed to be remaining at the end of
Tab stops: Not at 1.87 cm + 3.74 cm
DSV_TLVDLC
the lane changediscretionary lane change
Formatted: Font: 10 pt
minimum distance to keep between SV and TLV at low speed based on a predetermined
Formatted: Font: 10 pt
D FRU
SV_TLVmin
distance limitfallback-ready user
Formatted: Font: 10 pt
distance between the TFV and SV required and assumed to be remaining at the end of
Formatted: FooterCentered, Left, Space Before: 0 pt,
DTFV_SV
the lane change
Line spacing: single, Tab stops: Not at 17.2 cm
Formatted: Font: 11 pt
© ISO 2025 – All rights reserved
HeaderCentered
Formatted:
Symbols and MeaningDefinition Font: Not Bold
Formatted:
abbreviatedAbbreviated
Formatted: Adjust space between Latin and Asian
terms
text, Adjust space between Asian text and numbers
minimum distance to keep between TFV and SV at low speed based on a predetermined Formatted Table
D
TFV_SVmin
distance limit
Font: Not Bold
Formatted:
DTFVrange detection range required to detect the distance between the SV and TFV
distance required to be detected between TFV and SV to determine a sufficient gap for
DTFVreg
executing a lane change
distance required to be detected between TLV and SV to determine a sufficient gap for
DTLVreg
executing a lane change
initial lane following vehicle, i.e. immediate following vehicle in the initial lane before
Formatted: Left, Adjust space between Latin and
IFV
Asian text, Adjust space between Asian text and
starting a lane change manoeuvre
Formatted: Adjust space between Latin and Asian
initial lane leading vehicle, i.e. immediate leading vehicle in the initial lane before
ILV
text, Adjust space between Asian text and numbers
starting a lane change manoeuvre
Formatted Table
maximum lateral acceleration the subject vehicle may generate during the
aLat_Acel_maxMCS
Formatted: Left, Adjust space between Latin and
DLCmotorway chauffeur systems
Asian text, Adjust space between Asian text and
ODD operational design domain
Adjust space between Latin and Asian
Formatted:
text, Adjust space between Asian text and numbers
RTI request to intervene
Formatted: Left, Adjust space between Latin and
aLat_Jerk_maxSV maximum lateral jerk the subject vehicle may generate during the DLC
Asian text, Adjust space between Asian text and
Font: Not Italic
target lane following vehicle, i.e. immediate following vehicle in the target lane before Formatted:
TFV
starting a lane change manoeuvre
Formatted: Adjust space between Latin and Asian
text, Adjust space between Asian text and numbers
T time gap between the SV and the TLV
gapSV_TLV
Formatted: Font: Not Italic
Adjust space between Latin and Asian
Formatted:
TgapTFV_SV time gap between the TFV and SV
text, Adjust space between Asian text and numbers
Formatted: Left, Adjust space between Latin and
target lane leading vehicle, i.e. immediate leading vehicle in the target lane before
TLV Asian text, Adjust space between Asian text and
starting a lane change manoeuvre
Formatted Table
reaction time of SV to start deceleration after the SV starts a lane change manoeuvre
T
SVreact Left, Adjust space between Latin and
Formatted:
towards the target lane
Asian text, Adjust space between Asian text and
assumed reaction time of the TFV to start the deceleration, after the SV starts a lane
Formatted: Adjust space between Latin and Asian
T
TFVreact
change manoeuvre towards the target lane
text, Adjust space between Asian text and numbers
Left, Adjust space between Latin and
Formatted:
Vlimit Speed limit of the motorway
Asian text, Adjust space between Asian text and
Formatted: Adjust space between Latin and Asian
Vsv current velocity of the SV as observed in real time
text, Adjust space between Asian text and numbers
Formatted Table
VTFV velocity of the following vehicle approaching in the target lane
V maximum assumed velocity of the following vehicle approaching in the target lane
TFVlimit
VTLV velocity of the leading vehicle in the target lane
FigureTable 2 shows the — Symbols Formatted: Default Paragraph Font
Symbols Definition
aLat_max maximum lateral acceleration the subject vehicle may generate during the DLC
Formatted: FooterPageNumber
ISO/DIS FDIS 23792-2:2025(en) Formatted: Font: Bold, English (United Kingdom)
Font: Bold, English (United Kingdom)
Formatted:
Formatted: Font: Bold
Symbols Definition Formatted: HeaderCentered, Left
aLat_Jerk_max maximum lateral jerk that the subject vehicle may generate during the DLC
c clearance
necessary deceleration to be generated by the SV for the vSV to become equivalent to
dSV
vTLV and to maintain the required distance between the TLV and the SV at steady state
d deceleration assumed to be performed by the TFV
TFV
dTLV deceleration assumed to be performed by the TLV
required distance between the SV and the TLV assumed to be remaining at the end of
DSV_TLV
the lane change
minimum distance to be maintained between the SV and the TLV at low speed, based
DSV_TLVmin
on a predetermined distance limit
relative distance between the TFV and the SV that would shorten while TFV decelerates
DTFVdec
at an assumed level (dTFV)
required distance between the TFV and the SV assumed to be remaining at the end of
D
TFV_SV
the lane change
minimum distance to be maintained between the TFV and the SV at low speed, based
DTFV_SVmin
on a predetermined distance limit
DTFVrange detection range required to detect the distance between the SV and the TFV
relative distance between the TFV and the SV that would shorten while TFV is assumed
DTFVreact
to react (t ) to start decelerating
TFVreact
required distance to be detected between the TFV and the SV to determine a sufficient
DTFVreq
gap for executing a lane change
relative distance between the TLV and the SV that would shorten while TLV decelerates
DTLVdec
at an assumed level (dTLV)
relative distance between the TLV and the SV that would shorten while TLV is assumed
D
TLVreact
to react (tTLVreact) to start decelerating
required distance to be detected between the TLV and the SV to determine a sufficient
D
TLVreq
gap for executing a lane change
tgap time gap
tgapSV_TLV time gap between the SV and the TLV
t time gap between the TFV and the SV
gapTFV_SV
reaction time of the SV to start deceleration after the SV starts a lane change
tSVreact
manoeuvre towards the target lane
assumed reaction time of the TFV to start the deceleration, after the SV starts a lane
t
TFVreact
change manoeuvre towards the target lane
assumed reaction time of the TLV to start the deceleration, after the SV starts a lane
t
TLVreact
change manoeuvre towards the target lane
v vehicle speed
vlimit speed limit of the motorway
v current velocity of the SV as observed in real time Formatted: Font: 10 pt
SV
Formatted: Font: 10 pt
v velocity of the following vehicle approaching in the target lane
TFV
Formatted: Font: 10 pt
vTLV velocity of the leading vehicle in the target lane
Formatted: FooterCentered, Left, Space Before: 0 pt,
Line spacing: single, Tab stops: Not at 17.2 cm
Formatted: Font: 11 pt
© ISO 2025 – All rights reserved
HeaderCentered
Formatted:
Figure 2 provides a description of the lanes and vehicles associated with the lane change. Table 1 shows the Space Before: 12 pt, Adjust space
Formatted:
between Latin and Asian text, Adjust space between
abbreviationsSee Table 1 for the relevant abbreviated terms.
Asian text and numbers
Key
Formatted: Key Title, Adjust space between Latin and
Asian text, Adjust space between Asian text and
1 IFV:
numbers, Tab stops: Not at 0.7 cm + 1.4 cm + 2.1 cm
2 SV
+ 2.8 cm + 3.5 cm + 4.2 cm + 4.9 cm + 5.6 cm +
3 ILV
6.3 cm + 7 cm
4 TLV
5 ALV
6 AFV
7 TFV
a
1 Initial lane Following Vehicle. Formatted: Fig Legend, No bullets or numbering,
Adjust space between Latin and Asian text, Adjust
2 SV: Subject Vehicle
space between Asian text and numbers, Tab stops:
Not at 0.7 cm + 1.4 cm + 2.1 cm + 2.8 cm + 3.5 cm
3 ILV: Initial lane Leading Vehicle
+ 4.2 cm + 4.9 cm + 5.6 cm + 6.3 cm + 7 cm
b
4 TLV: Target lane Leading Vehicle.
Formatted: Fig Legend, No bullets or numbering,
c Adjust space between Latin and Asian text, Adjust
5 ALV: Adjacent to target lane Leading Vehicle.
space between Asian text and numbers, Tab stops:
6 AFV: Adjacent to target lane Following Vehicle
Not at 0.7 cm + 1.4 cm + 2.1 cm + 2.8 cm + 3.5 cm
+ 4.2 cm + 4.9 cm + 5.6 cm + 6.3 cm + 7 cm
7 TFV: Target lane Following Vehicle
Formatted: FooterPageNumber
ISO/DIS FDIS 23792-2:2025(en) Formatted: Font: Bold, English (United Kingdom)
Font: Bold, English (United Kingdom)
Formatted:
Formatted: Font: Bold
a: Initial lane
Formatted: HeaderCentered, Left
b: Target lane
c: Adjacent to target lane
Figure 2 — Description of lanes and vehicles Formatted: None, Adjust space between Latin and
Asian text, Adjust space between Asian text and
numbers
5 Motorway chauffer systems (MCS) with discretionary lane change (DLC)
5.1 DLC functionality
Formatted: Adjust space between Latin and Asian
text, Adjust space between Asian text and numbers,
Tab stops: Not at 0.71 cm
A DLC -functionality -equipped MCS (hereafter referred to as “the a “system”) performperforms the entire
Adjust space between Latin and Asian
Formatted:
dynamic driving task (DDT) for lane changes when a manufacturer -defined motivation for lane change exists.
text, Adjust space between Asian text and numbers
Motivation for a lane change is based upon conditions designed for the system. Examples of possible
discretionary lane change motivations can be:
a) a) FRU makes an input to request a lane change; Formatted: Numbered + Level: 1 + Numbering Style:
a, b, c, … + Start at: 1 + Alignment: Left + Aligned at: 0
cm + Indent at: 0 cm, Adjust space between Latin and
b) b) to follow the lane of travel to keep the planned route;
Asian text, Adjust space between Asian text and
numbers, Tab stops: Not at 0.7 cm + 1.4 cm + 2.1 cm
c) c) to overtake the initial lane leading vehicle (ILV).
+ 2.8 cm + 3.5 cm + 4.2 cm + 4.9 cm + 5.6 cm +
6.3 cm + 7 cm
5.2 Lane change procedure Formatted: Adjust space between Latin and Asian
text, Adjust space between Asian text and numbers,
Tab stops: Not at 0.71 cm
The DLC is executed through the following phases. Figure 3Figure 3 illustrates the position of the SV at the
Formatted: Adjust space between Latin and Asian
start of each phase.
text, Adjust space between Asian text and numbers
None, Adjust space between Latin and
Figure 3 — Phases of DLC Formatted:
Asian text, Adjust space between Asian text and
numbers
— — Phase 0: Lane change functionality is idle and is in the standby state (refer to 6.2.1.3).6.2.1.3).
Formatted: Adjust space between Latin and Asian
Motivation for lane change does not exist.
text, Adjust space between Asian text and numbers,
Tab stops: Not at 0.7 cm + 1.4 cm + 2.1 cm + 2.8 cm
+ 3.5 cm + 4.2 cm + 4.9 cm + 5.6 cm + 6.3 cm + 7
— — Phase 1: Motivation for a lane change exists. The system executes the gap search.
— — Phase2Phase 2: start of a lane change procedure. The system will notify the FRU of the start of the
procedure. The procedure is indicated to surrounding vehicles with the turn indicator. It is up to the
Formatted: Font: 10 pt
manufacturer to determine how the lane change procedure is cancelled if the lane change manoeuvre
Formatted: Font: 10 pt
cannot be started within a certain time period.
Formatted: Font: 10 pt
Formatted: FooterCentered, Left, Space Before: 0 pt,
— — Phase 3: The sufficient gap conditions have been confirmed and lane change manoeuvre has started
Line spacing: single, Tab stops: Not at 17.2 cm
and DLC is in the active state (refer to 6.2.1.4),6.2.1.4), but the SV has not yet left the initial lane. The SV
Formatted: Font: 11 pt
© ISO 2025 – All rights reserved
HeaderCentered
Formatted:
leaves the initial lane after the turn signal is indicated for the specified period of time (refer to
6.2.1.4).6.2.1.4).
— — Phase 4: The system is performing a lane change and the SV has entered the target lane with at least
one tiretyre in contact with the lane marking (refer to 6.2.1.4).6.2.1.4).
— — Phase 5: The SV is approaching the end ofhas almost finished performing the lane change (point of no
return), wherei.e. the manoeuvre has been sufficiently conductedreached a sufficient point for it to be
considered that the target lane has becomeis now the travel lane, hence the. The lane change manoeuvre
may therefore be completed even though a new vehicle is detected to be approaching from behind in,
within the area of the sufficient gap. The SV should be positioned with at least half the lateral position at
the front tyres intowithin the target lane and no more than the SV, but not completely within the target
lane.
— — Phase 6: The SV is at the end ofhas finished performing the lane change and all tyres are completely
within the target lane, then the. The lane change manoeuvre is therefore completed and the DLC goes
backreturns to the standby state (refer to 6.2.1.3).6.2.1.3). Lane centring may be performed separately in
order to position the vehicle within the target lane.
6 Requirements Formatted: Adjust space between Latin and Asian
text, Adjust space between Asian text and numbers
6.1 General Adjust space between Latin and Asian
Formatted:
text, Adjust space between Asian text and numbers,
Tab stops: Not at 0.71 cm
The system performs the lane change manoeuvre with the existence of a FRU. The system shall have detection,
Formatted: Adjust space between Latin and Asian
driver interface, manoeuvring and failure reaction functions as described in this clause (refer to 6.4.5).see also
text, Adjust space between Asian text and numbers
6.4.5).
6.2 State transitions Formatted: Adjust space between Latin and Asian
text, Adjust space between Asian text and numbers,
Tab stops: Not at 0.71 cm
The system shall, at a minimum, provide the operations and state transitions described in Figure 4
Formatted: Adjust space between Latin and Asian
below.Figure 4.
text, Adjust space between Asian text and numbers
Formatted: FooterPageNumber
ISO/DIS FDIS 23792-2:2025(en) Formatted: Font: Bold, English (United Kingdom)
Font: Bold, English (United Kingdom)
Formatted:
Formatted: Font: Bold
Formatted: HeaderCentered, Left
Formatted: Font: 10 pt
Formatted: Font: 10 pt
Formatted: Font: 10 pt
Formatted: FooterCentered, Left, Space Before: 0 pt,
Line spacing: single, Tab stops: Not at 17.2 cm
Formatted: Font: 11 pt
© ISO 2025 – All rights reserved
HeaderCentered
Formatted:
Key
DL1 DLC turned on
DL2 DLC conditions to start manoeuvre are satisfied
DL3 DLC manoeuvre completed
DL4 DLC turned off
M1 MCS turned on
M2 Engagement conditions are satisfied
M3 FRU override
M5 Disengagement-triggering condition detected
M6 FRU override
M7 MCS turned off
None, Adjust space
...
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