ISO 13674-1:2023

INTERNATIONAL ISO
STANDARD 13674-1
Third edition
2023-11
Road vehicles — Test method for
the quantification of on-centre
handling —
Part 1:
Weave test
Véhicules routiers — Méthode d'essai pour la quantification du
centrage —
Partie 1: Essai en petite sinusoïde au volant
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, definitions, and symbols .1
4 Principle . 2
5 Variables . 2
5.1 Reference system . 2
5.2 Variables to be measured . 2
6 Measuring equipment . 3
6.1 Description . 3
6.2 Transducer installations . 3
6.3 Data processing. 3
7 Test conditions .3
7.1 General . 3
7.2 Test track . 3
7.3 Wind velocity . 4
7.4 Test vehicle . 4
7.4.1 General data . . . 4
7.4.2 Tyres . 4
7.4.3 Operating components . 4
7.4.4 Loading conditions of vehicle . 4
8 Procedure .5
8.1 Warm-up . 5
8.2 Initial driving condition . 5
8.3 Weave test procedure . 5
9 Data evaluation and presentation of results . 6
9.1 General . 6
9.2 Time histories . 6
9.3 Characteristic values . 6
9.3.1 General . 6
9.3.2 Steering-wheel torque versus steering-wheel angle (M versus δ ) . 8
H H
9.3.3 Yaw velocity versus steering-wheel angle (dψ/dt versus δ ). 8
H
9.3.4 Yaw velocity versus steering-wheel torque (dψ/dt versus M ) . . 8
H
9.3.5 Lateral acceleration versus steering-wheel angle (a versus δ ) .
Y H
............................................................................................................................................................................................................ 8
9.3.6 Steering-wheel torque versus lateral acceleration (M versus a ) . 8
H Y
Bibliography .10
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.
This third edition cancels and replaces the second edition (ISO 13674:2010), which has been technically
revised.
The main changes are as follows:
— references have been updated to ISO 15037-1:2019 and deleted reference to ISO/TS 20119:2002;
— corrected the key for the abscissa and ordinate dead band in Figure 1;
— removed calculated lateral acceleration to calculate lateral acceleration metrics;
— corrected incomplete steering hysteresis calculation.
A list of all parts in the ISO 13674 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
The main purpose of this document is to provide repeatable and discriminatory test results.
The dynamic behaviour of a road vehicle is a very important aspect of active vehicle safety. Any given
vehicle, together with its driver and the prevailing environment, constitutes a closed-loop system that
is unique. The task of evaluating the dynamic behaviour is therefore, very difficult since the significant
interaction of these driver-vehicle-environment elements are each complex in themselves. A complete
and accurate description of the behaviour of the road vehicle necessarily involves information obtained
from a number of different tests.
Since this test method quantifies only one small part of the complete vehicle handling characteristics,
the results of these tests can only be considered significant for a correspondingly small part of the
overall dynamic behaviour.
Moreover, insufficient knowledge is available concerning the relationship between overall vehicle
dynamic properties and accident avoidance. A substantial amount of work is necessary to acquire
sufficient and reliable data on the correlation between accident avoidance and vehicle dynamic
properties in general and the results of these tests in particular. Consequently, for any application of this
test method for regulation purposes, proven correlation between test results and accident statistics is
important.
v
INTERNATIONAL STANDARD ISO 13674-1:2023(E)
Road vehicles — Test method for the quantification of on-
centre handling —
Part 1:
Weave test
1 Scope
This document specifies a test schedule that addresses a particular aspect of the on-centre handling
characteristics of a vehicle: the weave test. It is applicable to passenger cars in accordance with
ISO 3833, and to light trucks.
NOTE The manoeuvre specified in this test method is not representative of real driving conditions but is
useful for obtaining measures of vehicle on-centre handling behaviour in response to a specific type of steering
input under closely controlled test conditions. Other aspects of on-centre handling are addressed in the
companion ISO 13674-2.
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 1176, Road vehicles — Masses — Vocabulary and codes
ISO 2416, Passenger cars — Mass distribution
ISO 3833, Road vehicles — Types — Terms and definitions
ISO 8855, Road vehicles — Vehicle dynamics and road-holding ability — Vocabulary
ISO 15037-1:2019, Road vehicles — Vehicle dynamics test methods — Part 1: General conditions for
passenger cars
3 Terms, definitions, and symbols
For the purposes of this document, the terms and definitions given in ISO 1176, ISO 2416, ISO 3833,
ISO 8855 and the following 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
on-centre handling
description of the steering “feel” and precision of a vehicle during nominally straight-line driving and in
negotiating large radius bends at high speeds but low lateral accelerations
3.2
ordinate deadband
vertical width of the hysteresis loops at abscissa zero
3.3
abscissa deadband
horizontal width of the hysteresis loops at ordinate zero
3.4
gradient
ratio of change in the ordinate with respect to a unit change in the abscissa, evaluated on each side of
the hysteresis loop
4 Principle
On-centre handling represents that part of the straight-line directional stability characteristics of the
vehicle existing at lateral acceleration levels, typically no greater than 1 m/s . On-centre handling is
concerned primarily with features that directly influence the driver's steering input, such as steering
system and tyre characteristics. Thus, test schedules for the evaluation of on-centre handling behaviour
seek to minimize other factors that influence the wider aspects of straight-line directional stability,
such as disturbance inputs due to ambient winds and road irregularities.
This document defines a test schedule that involves driving the vehicle in a nominally straight line
at a constant forward speed. During the test, driver inputs and vehicle responses are measured and
recorded. From the recorded signals, characteristic values are calculated.
5 Variables
5.1 Reference system
The variables of motion used to describe vehicle behaviour in a test-specific driving situati
...