ISO/PAS 11585:2023

PUBLICLY ISO/PAS
AVAILABLE 11585
SPECIFICATION
First edition
2023-09
Road vehicles — Partial driving
automation — Technical
characteristics of conditional hands-
free driving systems
Véhicules routiers — Automatisation partielle de la conduite —
Caractéristiques techniques des systèmes de conduite mains-libres
conditionnels
Reference number
© ISO 2023
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Functionality .3
4.1 Overall system context . 3
4.2 General requirements . 5
4.3 State: L2 hands-free . 6
4.3.1 Control loop. 6
4.3.2 Possibility for the driver to deactivate, overrule and override the L2 hands-
free state . 6
4.3.3 ODD monitoring . 7
4.3.4 Driver monitoring . 7
4.3.5 Driver information and warning . 7
4.4 Transitions . 8
4.4.1 Enter "L2 hands-free state" from "manual-driving mode", "L1-driving
mode" or "PADS active-driving mode" . 8
4.4.2 Leaving "L2 hands-free state" due to drivers' intervention . 8
4.4.3 Leaving "L2 hands-free state" due to system intervention . 8
4.4.4 Leaving "L2 hands-free state" due to risk-mitigation . 9
5 Technical characteristics of "L2 hands-free subsystems". 9
5.1 Driver-monitoring system . 9
5.2 Driver information and warning system . 10
5.3 ODD-monitoring system . 10
5.4 Risk-mitigation system . 11
Annex A (informative) Driver information and warning system .12
Bibliography .14
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 22, Road vehicles, Subcommittee SC 33,
Vehicle dynamics, chassis components and driving automation systems testing.
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
This document can be used as a system level standard by other standards, which extend the combination
of ACC according to ISO 15622 and PADS according to ISO 21717 with additional requirements motivated
by costumer use-cases and by safety to a more detailed standard for a higher level of functionality
which will include the hands-free use case in certain conditions.
The main functionality of a "L2 hands-free system" is to control and limit the vehicle behaviour for
longitudinal and lateral control, as it is described in ISO 15622 and ISO 21717, with respect to the
performance, the intended ODD and the driver’s capabilities. Together with an appropriate driver
monitoring, which is typically realized with a driver monitoring camera and in addition a hands-on/
off detection regarding to the steering wheel, it is possible for a system to operate while the driver can
take the hands away from the steering without losing the ability and the responsibility to control the
DDT.
This document contains the basic control strategy, basic driver interface elements and a minimum set of
requirements for a L2 hands-free system. This document is applicable for, but not limited to, passenger
cars. It is not applicable to automated driving systems of Level 3 according to ISO/SAE PAS 22736 or
higher.
While a lane change functionality is not specified in this document, it is explicitly considered.
Regional regulation, e.g. UN/ECE R79, can limit the applicability of parts of this document.
v
PUBLICLY AVAILABLE SPECIFICATION ISO/PAS 11585:2023(E)
Road vehicles — Partial driving automation — Technical
characteristics of conditional hands-free driving systems
1 Scope
This document provides technical characteristics of partial driving automation system according to
ISO/SAE PAS 22736 and associated control strategies enabling hands-free driving.
These technical characteristics, together with an appropriate operational design domain enable the
proper usage of such partial driving automation systems which is supervised by drivers.
This document does not address performance limits, verification and validation of such systems.
2 Normative references
There are no normative references in this document.
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
ODD
operational design domain
operating conditions under which the driving automation system is specifically designed to function,
including, but not limited to, environmental, geographical, and time-of-day restrictions, and/or the
requisite presence or absence of certain traffic or roadway characteristics
[SOURCE: ISO/SAE PAS 22736:2021, 3.21, modified —The notes to entry and examples have been
removed.]
3.2
EOR
eyes-on request
request by the L2 hands-free system to the driver to monitor the traffic situation
3.3
HOW
hands-on warning
warning by the L2 hands-free system to the driver to direct control (3.12) the vehicle, at least by lateral
steering control of the vehicle
Note 1 to entry: An HOW could be represented by a yellow warning signal accompanied by an acoustic warning.
3.4
HOA
hands-on alert
alert by the L2 hands-free system to the driver to direct control (3.12) the vehicle immediately, at least
by lateral steering control of the vehicle
Note 1 to entry: A HOA could be represented by a red warning signal accompanied by an acoustic warning.
3.5
DMS
driver-monitoring system
system that detects the presence of a driver, assesses the driver's attention towards the traffic and
assesses hands-on/off detection on steering wheel
Note 1 to entry: One part of a driver-monitoring system is typically a driver-monitoring camera (3.6) and/or other
suitable means, e.g. capacitive hands-on/off detection.
3.6
DMC
driver-monitoring camera
camera as part of the driver-monitoring system (3.5) which can determine the driver’s attention towards
the traffic
3.7
driver information and warning system
system that informs the driver about the system status and warns the driver when actions are required
by the driver
EXAMPLE Eyes-on request (3.2), hands-on warning (3.3).
3.8
overrule
action by the driver to direct control (3.12) of lateral and/or longitudinal motion of the vehicle which
deactivates the L2 hands-free system
Note 1 to entry: Overrule is a possibility to deactivate the L2 hands-free system.
3.9
override
direct control (3.12) of lateral and/or longitudinal motion of the vehicle within a defined threshold
without deactivation of the L2 hands-free system
3.10
hands-free
system condition under which the driver is permitted to remove his hands from the steering wheel
Note 1 to entry: Part of the system condition is that the vehicle is in a specified operational design domain (3.1),
the driver monitors the traffic situation and system behaviour while the system monitors the driver.
3.11
hands-on
condition of the driver to hold the steering wheel
Note 1 to entry: During "L2 hands-on driving mode", the driver directly controls the vehicle either with or
without support by a " L2 hands-free system " or a "L2 hands-on system".
3.12
direct control
control of the vehicle by the driver by holding or moving the steering wheel or using brake or driving
pedal
Note 1 to entry: Within this document the acceleration is always positive and the negative acceleration is called
deceleration.
3.13
DDT
dynamic driving task
control and execution of longitudinal and lateral movements of the vehicle
3.14
mode
behaviour of the driver in interaction with the system which depends on system states
EXAMPLE In an L2 hands-on driving mode the driver’s hands are on the steering wheel, while the system
can either be in L2 hands-on state or in L2 hands-free state with the corresponding technical requirements.
Note 1 to entry: The mode may differ from the state (3.15) of the system.
3.15
state
execution of implemented requirements depending on system and environmental conditions
4 Functionality
4.1 Overall system context
This document focus on requirements of the "L2 hands-free state" with the corresponding transitions
as shown in Figure 1. The other states beside “lateral only” are briefly described only for completeness
in this clause and those are defined in ISO 15622 and ISO 21717.
Figure 1 — L2 hands-free system modes, states and transitions in interaction with ACC
(ISO 15622), PADS (ISO 21717) and lateral only
In this document the overall functionality of an "L2 hands-free system" is represented by an overall
system-state-diagram with states and transitions. Therefore, it is possible to describe an L2 hands-
free system with function modes from a customer perspective and with states and transition from
a technical point of view. Functionality-like features or subfeatures can be distributed via several or
other states.
Transitions will describe the trigger conditions which are needed to leave or to enter a state.
State "PADS off" (ISO 21717:2018, 6.1.1):
— in the state "PADS off" there is no action performed;
— the "ON" transition from state "PADS off" to state "PADS stand-by" can be performed by the driver
or automatically, e.g. after the ignition is switched on.
State "PADS stand-by" (ISO 21717:2018, 6.1.2):
— in the state "PADS stand-by" the system is ready to be activated while the driver is performing the
DDT manually;
— the transition "ACTIVATE" from "PADS stand-by" to "PADS active" can be initiated by the driver. The
transition "ACTIVATE" could lead to "PADS longitudinal" or to "PADS longitudinal lateral" state as
a part of the “L2 hands-on driving mode". A possible transition to "lateral only" is not described in
any ISO standard yet;
— a transition to activate "L2 hands-free state" could be initiated automatically or by the driver when
the conditions for the option for "L2 hands-free driving mode" are fulfilled.;
— the transition "OFF" from "PADS stand-by" to "PADS off" can be performed by the driver or
automatically, e.g. after the ignition is switched off or a system failure has occurred.
State "lateral only":
— in "lateral only" the system does not perform accelerating or decelerating actions. This state is not
described in any ISO standards, it is not used in context of this document;
— if the driver initiated all of the selected activation criteria for long-lateral, the system can perform
the transition lateral state to PADS longitudinal-lateral state.
State "PADS active" - (L2 hands-on mode) (ISO 21717:2018, 6.1.3):
— in both substates, "longitudinal-lateral" and "longitudinal", of the "PADS active" state the system
provides speed and distance control in accordance with ISO 15622. Therefore, longitudinal control
is always active in "PADS active" state as long as the driver does not intervene;
— in both substates, "longitudinal-lateral" and "longitudinal", of the "PADS active" state the system
evaluates the conditions for lateral control;
— depending on the substates, "longitudinal-lateral" and "longitudinal", the system within "PADS
active" evaluates the activation criteria for lateral control or lat-long control which are typically the
related ODD, speed, lane boundaries of the lane and/or relative distance to forward vehicles and the
drivers vehicle control;
— under certain driving conditions (ODD, driver, vehicle, monitoring systems active) it is possible to
take the hands off from steering wheel and switch to "hands-free" state which is described in more
detail in Clause 4;
— "PADS active" in both substates could be left to "PADS-off" or "PADS stand by" by "inactive" or
"direct-off" due to the driver's action, for example, brake, or automatically for instance after a
system failure has occurred.
State "PADS active" with "longitudinal" state as a substate (L2-hands-on-mode)
(ISO 21717:2018, 6.1.4):
— in "longitudinal state" (ACC) the system performs longitudinal control with or without vehicle in
front from standstill to a defined vehicle maximum speed;
— if all criteria for lateral control are met the system can perform the transition "LAT_ON" to PADS
longitudinal-lateral state, driver initiated or automatically.
State "PADS active" with longi
...