Road vehicles — Vehicle dynamics test methods — Part 3: General conditions for passenger cars ride comfort tests

This document specifies the general conditions that apply to vehicle ride comfort 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; — test reports (general data and test conditions). These items are of general significance, regardless of the specific vehicle ride comfort test method. They apply when vehicle ride comfort 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 mainly refers to road tests, but in many cases can be applied also for bench tests.

Véhicules routiers — Méthodes d'essai de la dynamique des véhicules — Partie 3: Conditions générales pour les essais de confort de conduite des voitures particulières

General Information

Status
Published
Publication Date
24-May-2022
Current Stage
4060 - Close of voting
Start Date
10-Aug-2021
Completion Date
09-Aug-2021
Ref Project

Buy Standard

Standard
ISO 15037-3:2022 - Road vehicles — Vehicle dynamics test methods — Part 3: General conditions for passenger cars ride comfort tests Released:5/25/2022
English language
20 pages
sale 15% off
Preview
sale 15% off
Preview

Standards Content (sample)

INTERNATIONAL ISO
STANDARD 15037-3
First edition
2022-05
Road vehicles — Vehicle dynamics test
methods —
Part 3:
General conditions for passenger cars
ride comfort tests
Véhicules routiers — Méthodes d'essai de la dynamique des
véhicules —
Partie 3: Conditions générales pour les essais de confort de conduite
des voitures particulières
Reference number
ISO 15037-3:2022(E)
© ISO 2022
---------------------- Page: 1 ----------------------
ISO 15037-3:2022(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2022

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
© ISO 2022 – All rights reserved
---------------------- Page: 2 ----------------------
ISO 15037-3:2022(E)
Contents Page

Foreword ..........................................................................................................................................................................................................................................v

Introduction .............................................................................................................................................................................................................................. vi

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 .................................................................................................................................................................................... 2

5.1 Description ................................................................................................................................................................................................. 2

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

5.3 Data processing...................................................................................................................................................................................... 4

6 Test conditions .......................................................................................................................................................................................................4

6.1 General ........................................................................................................................................................................................................... 4

6.2 Test track ..................................................................................................................................................................................................... 4

6.3 Wind velocity ........................................................................................................................................................................................... 4

6.4 Test vehicle ................................................................................................................................................................................................. 4

6.4.1 General data ................................... ........................................................................................................ ................................. 4

6.4.2 Tyres .............................................................................................................................................................................................. 5

6.4.3 Operating components .................................................................................................................................................. 5

6.4.4 Loading conditions of the vehicle ........................................................................................................................ 5

6.4.5 Drivetrain conditions of the vehicle .................................................................................................................. 5

6.4.6 Active systems ...................................................................................................................................................................... 6

7 Test methods ............................................................................................................................................................................................................ 6

7.1 General ........................................................................................................................................................................................................... 6

7.2 Primary ride ............................................................................................................................................................................................. 6

7.2.1 General ........................................................................................................................................................................................ 6

7.2.2 Random disturbances .................................................................................................................................................... 6

7.3 Secondary ride ........................................................................................................................................................................................ 6

7.3.1 General ........................................................................................................................................................................................ 6

7.3.2 Random disturbances .................................................................................................................................................... 7

7.3.3 Periodic disturbances .................................................................................................................................................... 7

7.4 Impact isolation ..................................................................................................................................................................................... 7

8 Data analysis ............................................................................................................................................................................................................ 7

8.1 Frequency weighting filters application (see ISO 2631, ISO 8041 and ISO 5349) ...................... 7

8.1.1 General ........................................................................................................................................................................................ 7

8.1.2 Health application ............................................................................................................................................................. 8

8.1.3 Comfort application ......................................................................................................................................................... 8

8.1.4 Perception application .................................................................................................................................................. 8

8.1.5 Motion sickness application ..................................................................................................................................... 8

8.2 Analysis techniques for random input tests: frequency domain ............................................................... 8

8.2.1 Power spectral density ................................................................................................................................................. 8

8.2.2 Transfer function ............................................................................................................................................................... 9

8.3 Analysis techniques for single events: time domain .......................................................................................... 10

8.3.1 Overall characterization - Global energy parameters ................................................................... 10

8.3.2 Single axle characterization .................................................................................................................................. 11

Annex A (normative) Test report — General data .............................................................................................................................12

Annex B (normative) Test report — Test conditions .......................................................................................................................16

Annex C (informative) Transducers and their installations ...................................................................................................18

iii
© ISO 2022 – All rights reserved
---------------------- Page: 3 ----------------------
ISO 15037-3:2022(E)

Bibliography .............................................................................................................................................................................................................................20

© ISO 2022 – All rights reserved
---------------------- Page: 4 ----------------------
ISO 15037-3:2022(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.
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.
© ISO 2022 – All rights reserved
---------------------- Page: 5 ----------------------
ISO 15037-3:2022(E)
Introduction

This document was developed to define general test conditions for passenger-cars ride comfort 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 and environment are comparable.
© ISO 2022 – All rights reserved
---------------------- Page: 6 ----------------------
INTERNATIONAL STANDARD ISO 15037-3:2022(E)
Road vehicles — Vehicle dynamics test methods —
Part 3:
General conditions for passenger cars ride comfort tests
1 Scope

This document specifies the general conditions that apply to vehicle ride comfort 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;
— test reports (general data and test conditions).

These items are of general significance, regardless of the specific vehicle ride comfort test method.

They apply when vehicle ride comfort 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 mainly refers to road tests, but in many cases can be applied also for bench tests.

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

— ISO Online browsing platform: available at https:// www .iso .org/ obp
© ISO 2022 – All rights reserved
---------------------- Page: 7 ----------------------
ISO 15037-3:2022(E)
— IEC Electropedia: available at https:// 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).
4.2 Variables to be determined

To describe the vehicle ride comfort in terms of vehicle response, the principal relevant variables are

the following:
— general vehicle dynamics variables, as defined in ISO 8855:
— longitudinal velocity (v );
— roll velocity (dφ/dt);
— pitch velocity (dθ/dt);
— roll angle (φ);
— pitch angle (θ);

— whole-body vibrations (WBV), like accelerations on hands, feet, pelvis and back;

— accelerations on the unsprung masses (i.e. on hubs, etc.);
— accelerations on the sprung mass:
— outside the cockpit (i.e. on suspension attachments points, etc.);
— inside the cockpit (i.e. on steering wheel, seat rail, drive floor, etc.);
— accelerations in the engine compartment.

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.

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. In Table 1 there are also the

typical temperature operating ranges and the recommended transducers’ IP code (the classification

of degrees of protection provided by enclosures for electrical equipment from external influences or

conditions like dirt and water).
© ISO 2022 – All rights reserved
---------------------- Page: 8 ----------------------
ISO 15037-3:2022(E)

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

Recommended IP
Typical oper- Recommended maxi- Temperature
Variable Axes
ating range mum “overall” error operating range
(IEC 60529)
±1 km/h for
v < 100 km/h 1st digit: 5 or higher
0 km/h to X
Velocity X -10/+40 °C
180 km/h
±2 km/h for 2nd digit: 1 or higher
v > 100 km/h
±0,3°/s for dθ/dt < 20°/s 1st digit: 5 or higher
Pitch velocity Y −50°/s to 50°/s -10/+40 °C
±1°/s for dθ/dt > 20°/s 2nd digit: 1 or higher
±0,3°/s for dφ/dt < 20°/s 1st digit: 5 or higher
Roll velocity X −50°/s to 50°/s -10/+40 °C
±1°/s for dφ/dt > 20°/s 2nd digit: 1 or higher
1st digit: 5 or higher
Roll angle X −15° to 15° ±0,15° -10/+40 °C
2nd digit: 1 or higher
1st digit: 5 or higher
Pitch angle Y −15° to 15° ±0,15° -10/+40 °C
2nd digit: 1 or higher
2 1st digit: 5 or higher
Accelerations −30 m/s to
X,Y,Z ±0,3 m/s -10/+40 °C
WBV 30 m/s
2nd digit: 1 or higher
Accelerations
2 1st digit: 5 or higher
on sprung −15 m/s to
X,Y,Z ±0,15 m/s -10/+40 °C
masses inside 15 m/s
2nd digit: 1 or higher
the cockpit
Accelerations
on sprung
2 1st digit: 6
−20 m/s to
masses X,Y,Z ±0,2 m/s -30/+70 °C
20 m/s
2nd digit: 2 or higher
outside the
cockpit
Accelerations
2 1st digit: 6
−50 m/s to
on the un- X,Y,Z ±0,5 m/s -30/+70 °C
50 m/s
2nd digit: 5 or higher
sprung masses
Accelerations
2 1st digit: 6
−50 m/s to
in the engine X,Y,Z ±0,5 m/s -10/+90 °C
50 m/s
2nd digit: 2 or higher
compartment

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).

Some of the variables included in Table 1 are measured directly on driver/vehicle interface, in particular

accelerations WBV and some accelerations on sprung masses inside the cockpit such as steering wheel

accelerations. For this reason, they are strongly influenced by the driver. When different vehicles are

compared it is recommended to have the same driver in all the tests used in the comparison.

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, or the variables

defined in this norm, can be determined.

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

carried out.
All the positions of the transducers shall be stated in Annex A.

NOTE The correct position of these transducers, that determinate the new variables, is in Annex C.

© ISO 2022 – All rights reserved
---------------------- Page: 9 ----------------------
ISO 15037-3:2022(E)
5.3 Data processing

The band of human sensitivity is between 0 Hz and 100 Hz (see ISO 2631/ISO 8041), but for the analysis,

the frequency range relevant for tests on comfort dynamics of passenger cars is between 0 Hz and the

maximum utilized frequency: f = 50 Hz.
max

The bandwidth of the entire, combined transducer/recording system shall be more than 500 Hz and

amplitude errors shall be less than ±0,5 %.

If the time history has an offset, that is the time history is not centred around 0, it is important to cancel

this offset calculating the mean value of the points of the time history (all or only a section) and subtract

it from all the points. The signals also shall be filtered with a low-pass filter (like a Butterworth filter),

with a gain in the passband of 1 ± 0,005 (100 ± 0,5 %) and in the stopband ±0,01 (±1 %) with the cut-off

frequency not before 100 Hz. All the data have to be resampling at the same frequency, not less than

500 Hz.
See ISO 15037-1 for an example of filter.
6 Test conditions
6.1 General

Limits and specifications for the ambient conditions and vehicle test conditions are established in

Clause 6. 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 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

Ride comfort analysis is really sensitive to roughness and road profile. The track profile shall be added

in the test report.

The track shall have different characteristics as a function of the type of the test: smooth road (like a

highway), uneven road (like a rough country road) and urban obstacles (like cleats, humps, steps etc.).

6.3 Wind velocity

The ambient wind velocity shall not exceed 5 m/s and not have gusts during a test. For each test method,

the climatic conditions shall be recorded in the test report (see Annex B).
The tests shall not be performed with heavy rain and puddles.
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 the vehicle's 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. Before the test start, it is recommended

the have the vehicle in a garage with a temperature between 0 and 40 °C.
© ISO 2022 – All rights reserved
---------------------- Page: 10 ----------------------
ISO 15037-3:2022(E)
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 being run in, the tyres shall be

maintained in the same positions in the vehicle 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.

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 it is taken into account when making comparisons between vehicles or between

tyres.
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 in accordance with ISO 1176 (code

ISO-M06) plus driver and test equipment (combined mass should not exceed 150 kg) and the maximum

authorized total mass in accordance with ISO 1176 (code ISO-M08).

The maximum authorized axle loads in accordance with 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.
© ISO 2022 – All rights reserved
---------------------- Page: 11 ----------------------
ISO 15037-3:2022(E)
6.4.6 Active systems

For vehicles with active systems influencing the test results, such as active suspensions, the different

ride 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 methods
7.1 General
Vehicle ride comfort testing is here divided into three different areas:

— primary ride which is low frequency excitation of the sprung mass (0-5) Hz, mainly evaluating

control and balance of the sprung mass of the vehicle;

— secondary ride is evaluated in the range of the natural frequencies of the unsprung mass and

secondary masses (e.g. steering wheel, powertrain) in the range of (5-25) Hz using random and

periodic disturbances;
— impact isolation testing to evaluate the influence of discrete impacts.

Typically, primary and secondary ride analysis is performed in the frequency domain and impact

isolation is evaluated in the time domain.
7.2 Primary ride
7.2.1 General

The purpose of evaluation of the primary ride is to quantify low frequency (0-5) Hz movements of the

vehicle due to small or large continuous road undulations and periodic disturbances. Split results for

small (class A-C) and large amplitude roads (class D-H). Primary ride is typically evaluated on body

shake, control (heave, pitch and roll) and balance (travel, roll and abruptness). Control is evaluated as

road copying at one end of the scale and “floating” the desired state. Balance in turn is evaluated as the

front/rear ratio of travel, roll and abruptness to analyse if and how any part of the motion is dominated

by the front or rear axle. Abruptness is here determined by if the body movements are not continuously

fluent, round and harmonic, but interrupted by jerky transitions/acceleration peaks along with

significant primary ride motion. Shake analysis in primary ride is focused on underdamped vibrations

of the sprung mass.
7.2.2 Random disturbances

The test methods associated with evaluating primary ride should, based on the above, focus on testing

the vehicle on roads that primarily excites the sprung mass with large and low amplitude motion

(different amplitudes to evaluate the non-linear characteristics of the suspension). Typically, one wants

to choose roads and test speeds that excite the heave, roll and pitch motion of the vehicle around the

natural fre
...

Questions, Comments and Discussion

Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.