ISO 7626-2:2015

Mechanical vibration and shock — Experimental determination of mechanical mobility — Part 2: Measurements using single-point translation excitation with an attached vibration exciter

ISO 7626-2:2015 specifies procedures for measuring linear mechanical mobility and other frequency-response functions of structures, such as buildings, machines and vehicles, using a single-point translational vibration exciter attached to the structure under test for the duration of the measurement. It is applicable to measurements of mobility, accelerance, or dynamic compliance, either as a driving-point measurement or as a transfer measurement. It also applies to the determination of the arithmetic reciprocals of those ratios, such as free effective mass. Although excitation is applied at a single point, there is no limit on the number of points at which simultaneous measurements of the motion response may be made. Multiple-response measurements are required, for example, for modal analyses.

Vibrations et chocs — Détermination expérimentale de la mobilité mécanique — Partie 2: Mesurages avec utilisation d'une excitation de translation en un seul point, au moyen d'un générateur de vibrations solidaire de ce point

General Information

• Status: Published
• Publication Date: 12-Apr-2015
• ICS: 17.160 - Vibrations, shock and vibration measurements
• Technical Committee: ISO/TC 108 - Mechanical vibration, shock and condition monitoring
• Drafting Committee: ISO/TC 108 - Mechanical vibration, shock and condition monitoring
• Current Stage: 9093 - International Standard confirmed
• Start Date: 17-Dec-2021
• Completion Date: 19-Apr-2025

Relations

• Consolidated By: ISO 19085-9:2019 - Woodworking machines — Safety — Part 9: Circular saw benches (with and without sliding table)
• Effective Date: 06-Jun-2022
• Revises: ISO 7626-2:1990 - Vibration and shock — Experimental determination of mechanical mobility — Part 2: Measurements using single-point translation excitation with an attached vibration exciter
• Effective Date: 14-Jul-2012

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 7626-2
Second edition
2015-04-01
Mechanical vibration and shock —
Experimental determination of
mechanical mobility —
Part 2:
Measurements using single-point
translation excitation with an attached
vibration exciter
Vibrations et chocs — Détermination expérimentale de la mobilité
mécanique —
Partie 2: Mesurages avec utilisation d’une excitation de translation en
un seul point, au moyen d’un générateur de vibrations solidaire de ce
point
Reference number
©
ISO 2015
© ISO 2015
All rights reserved. Unless otherwise specified, 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
Case postale 56 • CH-1211 Geneva 20
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail [e-mail]
Web www.iso.org
Published in Switzerland
ii © ISO 2015 – All rights reserved

Contents Page
Foreword .v
Introduction .vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Overall configuration of the measurement system . 2
5 Support of the structure under test . 3
5.1 General . 3
5.2 Grounded measurements . 3
5.3 Ungrounded measurements . 3
6 Excitation . 4
6.1 General . 4
6.2 Excitation waveforms . 4
6.2.1 General. 4
6.2.2 Discretely dwelled sinusoidal excitation . 4
6.2.3 Slowly swept sinusoidal excitation . 5
6.2.4 Stationary random excitation . 5
6.2.5 Other excitation waveforms . 5
6.3 Vibration exciters . 5
6.4 Avoidance of spurious forces and moments . 8
6.4.1 General. 8
6.4.2 Transducer mass loading . 8
6.4.3 Transducer rotational inertia loading . 8
6.4.4 Exciter attachment restraints . 8
7 Measurement of the exciting force and resulting motion response .9
7.1 General . 9
7.2 Attachment of transducers . 9
7.3 Mass loading and mass cancellation .10
7.4 Signal amplifiers .10
7.5 Calibrations .11
7.5.1 General.11
7.5.2 Operational calibration .11
8 Processing of the transducer signals .14
8.1 Determination of the frequency-response function .14
8.1.1 General.14
8.1.2 Sinusoidal excitation .14
8.1.3 Random excitation .14
8.2 Filtering .14
8.2.1 Sinusoidal excitation .14
8.2.2 Random excitation .14
8.3 Avoidance of saturation .15
8.4 Frequency resolution.15
8.4.1 General.15
8.4.2 Sinusoidal excitation .15
8.4.3 Random excitation .15
8.4.4 Periodic excitation .15
9 Control of the excitation .16
9.1 General .16
9.2 Time required for sinusoidal excitation .16
9.2.1 General.16
9.2.2 Discretely dwelled sinusoidal excitation .16
9.2.3 Slowly swept sinusoidal excitation .17
9.3 Time required for random excitation .17
9.4 Dynamic range.18
9.4.1 General.18
9.4.2 Sinusoidal excitation .18
9.4.3 Random excitation .18
10 Tests for valid data .18
11 Modal parameter identification .19
Annex A (normative) Tests for validity of measurement results .20
Annex B (normative) Requirements for excitation frequency increments and duration .23
Annex C (informative) Modal parameter identification .25
Bibliography .26
iv © ISO 2015 – All rights reserved

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 meaning of ISO specific terms and expressions related to conformity
assessment, as well as information about ISO’s adhe
...