Road vehicles -- Vehicle dynamics test methods

This document specifies the general conditions that apply when vehicle dynamics properties are determined according to ISO test methods. In particular, it specifies general conditions for: — variables; — measuring equipment and data processing; — environment (test track and wind velocity); — test vehicle preparation (tuning and loading); — initial driving; and — test reports (general data and test conditions). These items are of general significance, regardless of the specific vehicle dynamics test method. They apply when vehicle dynamics properties are determined, unless other conditions are required by the standard which is actually used for the test method. This document is applicable to passenger cars as defined in ISO 3833 and light trucks. NOTE The general conditions defined in existing vehicle dynamics standards are valid until a reference to this document is included. This document is cited in many other standards without a dated reference. In the course of its revision, no change in the numbering of clauses, tables and figures is anticipated.

Véhicules routiers -- Méthodes d'essai de la dynamique des véhicules

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Status
Published
Publication Date
09-Jan-2019
Current Stage
6060 - International Standard published
Start Date
30-Nov-2018
Completion Date
10-Jan-2019
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INTERNATIONAL ISO
STANDARD 15037-1
Third edition
2019-01
Corrected version
2019-03
Road vehicles — Vehicle dynamics test
methods —
Part 1:
General conditions for passenger cars
Véhicules routiers — Méthodes d'essai de la dynamique des
véhicules —
Partie 1: Conditions générales pour voitures particulières
Reference number
ISO 15037-1:2019(E)
ISO 2019
---------------------- Page: 1 ----------------------
ISO 15037-1:2019(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2019

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
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Phone: +41 22 749 01 11
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Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii © ISO 2019 – All rights reserved
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ISO 15037-1:2019(E)
Contents Page

Foreword ........................................................................................................................................................................................................................................iv

Introduction ..................................................................................................................................................................................................................................v

1 Scope ................................................................................................................................................................................................................................. 1

2 Normative references ...................................................................................................................................................................................... 1

3 Terms and definitions ..................................................................................................................................................................................... 1

4 Variables ....................................................................................................................................................................................................................... 2

4.1 Reference system .................................................................................................................................................................................. 2

4.2 Variables to be determined .......................................................................................................................................................... 2

5 Measuring equipment ..................................................................................................................................................................................... 3

5.1 Description ................................................................................................................................................................................................. 3

5.2 Transducer installations ................................................................................................................................................................. 3

5.3 Data processing ...................................................................................................................................................................................... 3

5.3.1 General...................................................................................................................................................................................... 3

5.3.2 Analogue data processing ........................................................................................................................................ 4

5.3.3 Digital data processing ............................................................................................................................................... 4

6 Test conditions ....................................................................................................................................................................................................... 5

6.1 General ........................................................................................................................................................................................................... 5

6.2 Test track ...................................................................................................................................................................................................... 6

6.3 Wind velocity ............................................................................................................................................................................................ 6

6.4 Test vehicle ................................................................................................................................................................................................. 6

6.4.1 General data ......................................................................................................................................................................... 6

6.4.2 Tyres ........................................................................................................................................................................................... 6

6.4.3 Operating components ............................................................................................................................................... 7

6.4.4 Loading conditions of the vehicle ...................................................................................................................... 7

6.4.5 Drivetrain conditions of the vehicle ................................................................................................................ 7

6.4.6 Active systems .................................................................................................................................................................... 7

7 Test method ............................................................................................................................................................................................................... 7

7.1 Warm-up....................................................................................................................................................................................................... 7

7.2 Initial driving condition .................................................................................................................................................................. 7

7.2.1 General...................................................................................................................................................................................... 7

7.2.2 Steady-state straight-ahead run ......................................................................................................................... 8

7.2.3 Steady-state circular run ........................................................................................................................................... 8

Annex A (normative) Test report — General data ...............................................................................................................................10

Annex B (normative) Test report — Test conditions ........................................................................................................................14

Annex C (informative) Transducers and their installations......................................................................................................16

Annex D (informative) Analogue filtering: Butterworth filter ................................................................................................20

© ISO 2019 – All rights reserved iii
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ISO 15037-1:2019(E)
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 documents 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).

Attention is drawn to the possibility that some of the elements of this document may be the subject of

patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of

any patent rights identified during the development of the document will be in the Introduction and/or

on the ISO list of patent declarations received (see www .iso .org/patents).

Any trade name used in this document is information given for the convenience of users and does not

constitute an endorsement.

For an explanation on 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 and chassis components.

This third edition cancels and replaces the second edition (ISO 15037-1:2006), which has been

technically revised. The main changes compared to the previous edition are as follows:

— Recognizing regenerative braking and active control systems.

This corrected version of ISO 15037-1:2019 incorporates the following corrections:

— the date has been corrected to 2019 in the headers and footers.
A list of all parts in the ISO 15037 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 © ISO 2019 – All rights reserved
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ISO 15037-1:2019(E)
Introduction

This document was developed to define general test conditions for vehicle dynamic tests. Any given

vehicle, together with its driver and the prevailing environment, constitutes a unique closed-loop

system. The task of evaluating the dynamic behaviour of the vehicle is therefore very difficult since

there is significant interaction between these driver-vehicle-environment elements, and each of these

elements is individually complex in itself.

The test conditions exert large influence on the test results. Only test results obtained at identical test

conditions are comparable.
© ISO 2019 – All rights reserved v
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INTERNATIONAL STANDARD ISO 15037-1:2019(E)
Road vehicles — Vehicle dynamics test methods —
Part 1:
General conditions for passenger cars
1 Scope

This document specifies the general conditions that apply when vehicle dynamics properties are

determined according to ISO test methods.
In particular, it specifies general conditions for:
— variables;
— measuring equipment and data processing;
— environment (test track and wind velocity);
— test vehicle preparation (tuning and loading);
— initial driving; and
— test reports (general data and test conditions).

These items are of general significance, regardless of the specific vehicle dynamics test method. They

apply when vehicle dynamics properties are determined, unless other conditions are required by the

standard which is actually used for the test method.

This document is applicable to passenger cars as defined in ISO 3833 and light trucks.

NOTE The general conditions defined in existing vehicle dynamics standards are valid until a reference to

this document is included.

This document is cited in many other standards without a dated reference. In the course of its revision,

no change in the numbering of clauses, tables and figures is anticipated.
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
3 Terms and definitions

For the purposes of this document, the terms and definitions given in ISO 8855 apply.

© ISO 2019 – All rights reserved 1
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ISO 15037-1:2019(E)

ISO and IEC maintain terminological databases for use in standardization at the following addresses:

— ISO Online browsing platform: available at https: //www .iso .org/obp
— IEC Electropedia: available at http: //www .electropedia .org/
4 Variables
4.1 Reference system

The variables of motion used to describe vehicle behaviour in a test-specific driving situation relate to

the intermediate axis system (X, Y, Z) (see ISO 8855).

The location of the origin of the vehicle axis system (X , Y , Z ) is the reference point, and this position

V V V
shall be reported (see Annex A).

NOTE Useful positions for the reference point include (1) the centre of gravity of the vehicle and (2) a fixed

point of geometry such as the point in the longitudinal plane of symmetry at the height of the centre of gravity

and at mid-wheelbase. Locating the reference point at the centre of gravity is very useful for analytical evaluation

of the test results of individual vehicles, but can cause difficulty in comparing results for different vehicles.

Locating the reference point at the geometrical position is more convenient for comparing results from different

tests, but can complicate theoretical analysis.
4.2 Variables to be determined

To describe the vehicle dynamics in terms of driver input and vehicle response, the principal relevant

variables are the following:
— steering-wheel angle (δ );
— steering-wheel torque (M );
— longitudinal velocity (v );
— sideslip angle (β) or lateral velocity (v );
— longitudinal acceleration (a );
— lateral acceleration (a );
— yaw velocity (dψ/dt);
— roll velocity (dφ/dt);
— pitch velocity (dθ/dt);
— roll angle (φ);
— pitch angle (θ).
These variables are defined in ISO 8855.

All standards that make reference to this document shall specify which variables apply. Depending on

the specific standard, additional variables can be required or recommended.

NOTE These variables can be determined directly by measuring or by calculation from measured values.

2 © ISO 2019 – All rights reserved
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ISO 15037-1:2019(E)
5 Measuring equipment
5.1 Description

Time histories of the measured variables shall be recorded by a time-based multi-channel recording

system by means of appropriate transducers (see Annex C). Typical operating ranges and recommended

maximum errors of the transducer and recording system are shown in Table 1. The specified accuracies

should be achieved whether the variables are measured or are calculated.

Table 1 — Variables, their typical operating ranges and recommended maximum errors

Recommended maximum “overall”
Variable Typical operating range
error
Steering-wheel angle −360° to 360° ±1° for δ < 50°
±2° for δ > 50° and < 180°
±4° for δ > 180°
Steering-wheel torque −30 Nm to 30 Nm ±0,1 Nm for M < 10 Nm
±0,3 Nm for M > 10 Nm
Longitudinal velocity 0 km/h to 180 km/h ±1 km/h for v < 100 km/h
±2 km/h for v > 100 km/h
Lateral velocity −10 m/s to 10 m/s ±0,2 m/s
Sideslip angle −20° to 20° ±0,3°
2 2 2
Longitudinal acceleration −15 m/s to 15 m/s ±0,15 m/s
2 2 2
Lateral acceleration −15 m/s to 15 m/s ±0,15 m/s
Yaw velocity −50°/s to 50°/s ±0,3°/s for dψ/dt < 20°/s
±1°/s for dψ/dt > 20°/s
Pitch velocity −50°/s to 50°/s ±0,3°/s for dθ/dt < 20°/s
±1°/s for dθ/dt > 20°/s
Roll velocity −50°/s to 50°/s ±0,3°/s for dφ/dt < 20°/s
±1°/s for dφ/dt > 20°/s
Roll angle −15° to 15° ±0,15°
Pitch angle −15° to 15° ±0,15°

Increased measurement accuracy may be desirable for computation of some of the characteristic values. If any system

error exceeds the recommended maximum value, this and the actual maximum error shall be stated in the test report (see

Annex A).
5.2 Transducer installations

The transducers shall be installed according to the manufacturer’s instructions when such instructions

exist, so that the variables corresponding to the terms and definitions of ISO 8855 can be determined.

If a transducer does not measure a variable in the defined position, appropriate transformation shall be

carried out.
5.3 Data processing
5.3.1 General

The frequency range relevant for tests on horizontal dynamics of passenger cars is between 0 Hz and

the maximum utilized frequency: f = 5 Hz. Based on whether analogue or digital data processing

max
methods are used, the requirements given in 5.3.2 or in 5.3.3 apply.
© ISO 2019 – All rights reserved 3
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ISO 15037-1:2019(E)
5.3.2 Analogue data processing

The bandwidth of the entire, combined transducer/recording system shall be no less than 8 Hz.

In order to execute the necessary filtering of signals, low-pass filters shall be employed. The width of

the passband (from 0 Hz to frequency f at −3 dB) shall not be less than 9 Hz. Amplitude errors shall be

less than ±0,5 % in the relevant frequency range of 0 Hz to 5 Hz. All analogue signals shall be processed

with filters having sufficiently similar phase characteristics to ensure that time delay differences due

to filtering lie within the required accuracy for time measurement.

NOTE During analogue filtering of signals with different frequency contents, phase shifts can occur.

Therefore, a digital data processing method, as described in 5.3.3, is preferable.

5.3.3 Digital data processing
5.3.3.1 General considerations

Preparation of analogue signals includes consideration of filter amplitude attenuation and sampling rate

to avoid aliasing errors, and filter phase lags and time delays. Sampling and digitizing considerations

include pre-sampling amplification of signals to minimize digitizing errors; number of bits per

sample; number of samples per cycle; sample and hold amplifiers; and timewise spacing of samples.

Considerations for additional phaseless digital filtering include the selection of passbands and stopbands

and the attenuation and allowable ripple in each; and correction of filter phase lags. Each of these factors

shall be considered in order to achieve a relative overall data acquisition accuracy of ±0,5 %.

Attenuation and phase shift information for a Butterworth filter is provided in Annex D.

5.3.3.2 Aliasing errors and anti-aliasing filters

In order to avoid uncorrectable aliasing errors, the analogue signals shall be appropriately filtered

before sampling and digitizing. The order of the filters used and their passband shall be chosen

according to both the required flatness in the relevant frequency range and the sampling rate.

The minimum filter characteristics and sampling rate shall be such that:

a) within the relevant frequency range of 0 Hz to f = 5 Hz, the maximum attenuation of the analogue

max
signal is less than the resolution of the digitized signal;

b) at one-half the sampling rate (i.e. the Nyquist or “folding” frequency), the magnitudes of all

frequency components of signal and noise are reduced to less than the digital resolution.

For 0,05 % resolution, the filter attenuation shall be less than 0,05 % to 5 Hz, and the attenuation shall

be greater than 99,95 % at all frequencies greater than one-half the sampling frequency.

It is recommended that anti-aliasing filters be of order four or higher (see Annex D).

Although filtering for anti-aliasing is required, excessive analogue filtering shall be avoided. Moreover,

all filters shall have sufficiently similar phase characteristics to ensure that differences in time delays

between signals are compatible with the required accuracy for the time measurement.

NOTE Phase shifts are especially significant when measured variables are multiplied together to form new

variables, because, while amplitudes multiply, phase shifts and associated time delays add up. Phase shifts and

time delays are reduced by increasing the filter cut-off frequency, f . Whenever formulae describing the pre-

sampling filters are known, it is practical to remove their phase shifts and time delays by simple algorithms

performed in the frequency domain.
5.3.3.3 Data sampling and digitizing

At 5 Hz, the signal amplitude changes by up to 3 % per millisecond. To limit dynamic errors caused by

changing analogue inputs to 0,1 %, sampling or digitizing time shall be less than 32 µs. Each pair or set

of data samples to be compared shall be taken simultaneously or within a sufficiently short time period.

4 © ISO 2019 – All rights reserved
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ISO 15037-1:2019(E)

The digitizing system shall have a resolution of 12 bits (±0,05 %) or more and an accuracy of 2 LSB

(±0,1 %). Amplification of the analogue signal before digitizing shall be such that, in the digitizing

process, the combined error due to the finite resolution and inaccuracy of digitizing is less than 0,2 %.

5.3.3.4 Digital filtering

For filtering of sampled data in data evaluation, phaseless (zero phase shift) digital filters shall be used

incorporating the following characteristics (see Figure 1):
— passband shall range from 0 Hz to 5 Hz;
— stopband shall begin between 10 Hz and 15 Hz;
— the filter gain in the passband shall be 1 ± 0,005 (100 ± 0,5 %);
— the filter gain in the stopband shall be ±0,01 (±1 %).
Key
f frequency (Hz)
Y filter gain
Passband.
Stopband.
Figure 1 — Required characteristics of phaseless digital filters
6 Test conditions
6.1 General

Limits and specifications for the ambient conditions and vehicle test conditions are established below.

These shall be maintained during the specific test. Any deviations shall be shown in the test report

(see Annexes A and B), including the individual diagrams of the presentation of results. For each test

© ISO 2019 – All rights reserved 5
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ISO 15037-1:2019(E)

method, the test-specific conditions and those which cannot be kept constant (e.g. tread depths) shall

be recorded in a separate test report in accordance with Annex B.
6.2 Test track

All tests shall be carried out on a smooth, clean, dry and uniform paved road surface. The gradient of

the paved test surface to be used shall not exceed 2 % (recommended 1,5 %) in any direction when

measured over any distance interval between that corresponding to the vehicle track and 25 m. For

each test, the road surface conditions and paving material shall be recorded in the test report (see

Annex B).
6.3 Wind velocity

The ambient wind velocity shall not exceed 5 m/s during a test. For each test method, the climatic

conditions shall be recorded in the test report (see Annex B).
6.4 Test vehicle
6.4.1 General data

General data of the test vehicle shall be presented in the test report shown in Annex A. For any change

of vehicle specification (e.g. load), the general data shall be documented again.

The test vehicle shall be a passenger car or light truck in accordance with ISO 3833. If a new vehicle is

used, it is recommended to make an adequate run-in before starting the tests.

Since in certain cases the ambient temperature has a significant influence on test results, this should be

taken into account when making comparisons between vehicles.
6.4.2 Tyres

For a general tyre condition, new tyres shall be fitted on the test vehicle according to the vehicle

manufacturer’s specifications. If not specified otherwise by the tyre manufacturer, they shall be run in

for at least 150 km on the test vehicle or an equivalent vehicle without excessively harsh use, for example

braking, acceleration, cornering, hitting the kerb, etc. After run in, the tyres shall be maintained in the

same vehicle positions for the tests.

Tyres shall have a tread depth of at least 90 % of the original value across the whole breadth of the

tread and around the whole circumference of the tyre.

Tyres shall not be manufactured more than one year before the test. The date of manufacturing shall be

noted in the presentation of test conditions (see Annex B).

Tyres shall be inflated to the pressure as specified by the vehicle manufacturer for the test vehicle

configuration at the ambient temperature of the test. The tolerance for setting the cold inflation

pressure is ±5 kPa for pressures up to 250 kPa and ±2 % for pressure above 250 kPa.

Inflation pressure and tread depth of the tyres determined before tyre warm-up shall be recorded in

the test report (see Annex B).

Tests may also be performed under conditions other than general tyre conditions. The details shall be

noted in the test report (see Annex B).

NOTE Tread breadth is the width of that part of the tread that, with the tyre correctly inflated, contacts the

road in normal straight-line driving.

As the tread depth or uneven tread wear can have a significant influence on test results, it is recommended

that they be taken into account when making comparisons between vehicles or between tyres.

−2 3 2
1) 1 kPa = 10 bar = 10 N/m .
6 © ISO 2019 – All rights reserved
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ISO 15037-1:2019(E)
6.4.3 Operating components

For the standard test condition, the type (e.g. part number or model number) and condition (e.g. shock-

absorber settings and suspension-geometry adjustments) of all components likely to influence the test

results shall be as specified by the manufacturer. Any deviations from manufacturer’s specifications

shall be noted in the presentation of general data (see Annex A).
6.4.4 Loading conditions of the vehicle

The test mass shall be between the complete vehicle kerb mass (ISO 1176, code ISO-M06) plus driver

and test equipment (combined mass should not exceed 150 kg) and the maximum authorized total mass

(ISO 1176, code ISO-M08).

The maximum authorized axle loads (ISO 1176, code ISO-M13) shall not be exceeded.

Care shall be taken to generate a minimum deviation in the location of the centre of gravity and in the

moments of inertia as compared to the loading conditions of the vehicle in normal use, in accordance

with ISO 2416. The resulting wheel loads shall be determined and recorded in the test report (see

Annex A).
6.4.5 Drivetrain conditions of the vehicle

For vehicles with regenerative braking capabilities, the specific vehicle configuration can alter the

dynamic vehicle behaviour while releasing the accelerator pedal and/or while pressing the brake pedal.

For these vehicles, the different dynamic vehicle behaviour with or without active regenerative braking

shall be considered while performing the tests. The selected level of regenerative braking capability

and the transmission lever position shall be documented in the test report.
6.4.6 Active systems

For vehicles with active systems influencing the test results, such as active steering, electronic stability

control or active suspensions, the different dynamic vehicle behaviours possible with different settings

of the systems shall be considered while performing the tests. If the driver can choose between

different settings of the system, e.g. by a “sport/comfort” switch, the settings chosen for the test shall

be documented in the test report.
7 Test method
7.1 Warm-up

All relevant vehicle components shall be warmed up prior to the tests in order to achieve component

temperatures representative of normal driving conditions. Tyres shall be warmed up prior to the tests

to achieve an equilibrium temperature and pressure representative of normal driving conditions.

A procedure equivalent to driving at the test speed for a distance of 10 km, or driving 500 m at a lateral

acceleration of 3 m/s (both left and right turns), is appropriate for warming up the tyres.

7.2 Initial driving condition
7.2.1 General

The initial driving condition is specified in most of the vehicle dynamics test methods. It can either be a

steady-state straight-ahead run or a steady-state circular run.

If there is no specific requirement defined in a test method standard, the tests shall be performed

in the highest suitable gear for vehicles with manual transmission and for vehicles with automatic

transmission in drive D. The pos
...

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