SIST-TS CEN ISO/TS 15530-1:2014

Geometrical product specifications (GPS) - Coordinate measuring machines (CMM): Technique for determining the uncertainty of measurement - Part 1: Overview and metrological characteristics (ISO/TS 15530-1:2013)

This part of ISO 15530 provides an overview of the ISO 15530 series. It discusses the metrological characteristics of coordinate measuring machines (CMMs), the sources of task-specific uncertainty, and the relationship between the ISO 10360 and ISO 15530 series.

Geometrische Produktspezifikation und -prüfung (GPS) - Verfahren zur Ermittlung der Messunsicherheit von Koordinatenmessgeräten (KMG) - Teil 1: Übersicht und metrologische Merkmale (ISO/TS 15530-1:2013)

Dieser Teil von ISO 15530 gibt einen Überblick über die ISO 15530-Serie. Er erläutert die metrologischen Merkmale von Koordinatenmessgeräten (KMG), die Ursachen der aufgabenspezifischen Messunsicherheit und die Beziehungen zwischen der ISO 10360- und der ISO 15530-Normenserie.

Spécification géométrique des produits (GPS) - Machines à mesurer tridimentionnelles (MMT): Technique pour la détermination de l'incertitude de mesure - Partie 1: Vue d'ensemble et caractéristiques métrologiques (ISO/TS 15530-1:2013)

L'ISO/TS 15530-1:2013 fournit une vue d'ensemble de la série ISO 15530. Elle traite des caractéristiques métrologiques des machines à mesurer tridimensionnelles (MMT), des sources d'incertitude de mesure spécifiques d'une tâche et de la relation entre les séries de l'ISO 10360 et l'ISO 15530.

Specifikacija geometrijskih veličin izdelka (GPS) - Koordinatni merilni stroji (CMM): postopek določevanja negotovosti meritev - 1. del: Pregled in metrološke karakteristike (ISO/TS 15530-1:2013)

Ta del standarda ISO 15530 podaja pregled serije standardov ISO 15530. Opisuje meroslovne značilnosti koordinatnih merilnih strojev (CMM), vire netočnosti glede na nalogo ter razmerje med serijama standardov ISO 10360 in ISO 15530.

General Information

• Status: Published
• Publication Date: 26-May-2014
• ICS: 17.040.30 - Measuring instruments
• ICS: 17.040.40 - Geometrical Product Specification (GPS)
• Technical Committee: ISEL - Mechanical elements
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 14-May-2014
• Due Date: 19-Jul-2014
• Completion Date: 27-May-2014
• Ref Project: CEN ISO/TS 15530-1:2013 - Geometrical product specifications (GPS) - Coordinate measuring machines (CMM): Technique for determining the uncertainty of measurement - Part 1: Overview and metrological characteristics (ISO/TS 15530-1:2013)

Standards Content (Sample)

SLOVENSKI STANDARD
SIST-TS CEN ISO/TS 15530-1:2014
01-julij-2014

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SRVWRSHNGRORþHYDQMDQHJRWRYRVWLPHULWHYGHO3UHJOHGLQPHWURORãNH
NDUDNWHULVWLNH,6276
Geometrical product specifications (GPS) - Coordinate measuring machines (CMM):
Technique for determining the uncertainty of measurement - Part 1: Overview and
metrological characteristics (ISO/TS 15530-1:2013)

Geometrische Produktspezifikation und -prüfung (GPS) - Verfahren zur Ermittlung der

Messunsicherheit von Koordinatenmessgeräten (KMG) - Teil 1: Übersicht und
metrologische Merkmale (ISO/TS 15530-1:2013)

Spécification géométrique des produits (GPS) - Machines à mesurer tridimentionnelles

(MMT): Technique pour la détermination de l'incertitude de mesure - Partie 1: Vue

d'ensemble et caractéristiques métrologiques (ISO/TS 15530-1:2013)
Ta slovenski standard je istoveten z: CEN ISO/TS 15530-1:2013
ICS:
17.040.30 Merila Measuring instruments
SIST-TS CEN ISO/TS 15530-1:2014 en

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST-TS CEN ISO/TS 15530-1:2014
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SIST-TS CEN ISO/TS 15530-1:2014
TECHNICAL SPECIFICATION
CEN ISO/TS 15530-1
SPÉCIFICATION TECHNIQUE
TECHNISCHE SPEZIFIKATION
September 2013
ICS 17.040.30
English Version
Geometrical product specifications (GPS) - Coordinate
measuring machines (CMM): Technique for determining the
uncertainty of measurement - Part 1: Overview and metrological
characteristics (ISO/TS 15530-1:2013)

Spécification géométrique des produits (GPS) - Machines à Geometrische Produktspezifikation und -prüfung (GPS) -

mesurer tridimentionnelles (MMT): Technique pour la Verfahren zur Ermittlung der Messunsicherheit von

détermination de l'incertitude de mesure - Partie 1: Vue Koordinatenmessgeräten (KMG) - Teil 1: Übersicht und

d'ensemble et caractéristiques métrologiques (ISO/TS metrologische Merkmale (ISO/TS 15530-1:2013)

15530-1:2013)

This Technical Specification (CEN/TS) was approved by CEN on 25 July 2011 for provisional application.

The period of validity of this CEN/TS is limited initially to three years. After two years the members of CEN will be requested to submit their

comments, particularly on the question whether the CEN/TS can be converted into a European Standard.

CEN members are required to announce the existence of this CEN/TS in the same way as for an EN and to make the CEN/TS available

promptly at national level in an appropriate form. It is permissible to keep conflicting national standards in force (in parallel to the CEN/TS)

until the final decision about the possible conversion of the CEN/TS into an EN is reached.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,

Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,

Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United

Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels

© 2013 CEN All rights of exploitation in any form and by any means reserved Ref. No. CEN ISO/TS 15530-1:2013: E

worldwide for CEN national Members.
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Contents Page

Foreword ..............................................................................................................................................................3

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CEN ISO/TS 15530-1:2013 (E)
Foreword

This document (CEN ISO/TS 15530-1:2013) has been prepared by Technical Committee ISO/TC 213

"Dimensional and geometrical product specifications and verification" in collaboration with Technical

Committee CEN/TC 290 “Dimensional and geometrical product specification and verification” the secretariat of

which is held by AFNOR.

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

rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.

According to the CEN-CENELEC Internal Regulations, the national standards organizations of the following

countries are bound to announce this Technical Specification: Austria, Belgium, Bulgaria, Croatia, Cyprus,

Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany,

Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland,

Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom.

Endorsement notice

The text of ISO/TS 15530-1:2013 has been approved by CEN as CEN ISO/TS 15530-1:2013 without any

modification.
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SIST-TS CEN ISO/TS 15530-1:2014
TECHNICAL ISO/TS
SPECIFICATION 15530-1
First edition
2013-09-01
Geometrical product specifications
(GPS) — Coordinate measuring
machines (CMM): Technique for
determining the uncertainty of
measurement —
Part 1:
Overview and metrological
characteristics
Spécification géométrique des produits (GPS) — Machines à mesurer
tridimentionnelles (MMT): Technique pour la détermination de
l’incertitude de mesure —
Partie 1: Vue d’ensemble et caractéristiques métrologiques
Reference number
ISO/TS 15530-1:2013(E)
ISO 2013
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SIST-TS CEN ISO/TS 15530-1:2014
ISO/TS 15530-1:2013(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2013

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 2013 – All rights reserved
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Contents Page

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

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

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

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

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

4 Metrological characteristics ..................................................................................................................................................................... 2

4.1 General ........................................................................................................................................................................................................... 2

4.2 Commerce ................................................................................................................................................................................................... 2

4.3 Internal use in an organization ................................................................................................................................................. 2

4.4 Identification, definition, and choice of metrological characteristics ..................................................... 2

4.5 Calibration of metrological characteristics .................................................................................................................... 3

5 Task-specific uncertainty............................................................................................................................................................................. 3

5.1 General ........................................................................................................................................................................................................... 3

5.2 Instrumentation factors .................................................................................................................................................................. 4

5.3 Measurement plan factors ............................................................................................................................................................ 4

5.4 Extrinsic factors ..................................................................................................................................................................................... 4

6 Techniques to determine task-specific measurement uncertainty components ..............................4

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

6.2 Sensitivity analysis .............................................................................................................................................................................. 4

6.3 Use of calibrated workpieces or standards (ISO 15530-3) .............................................................................. 5

6.4 Use of computer simulation (ISO/TS 15530-4) ......................................................................................................... 5

Annex A (informative) Relationship between CMM metrological characteristics,the ISO 10360

series of standards and the ISO 15530 series of standards .....................................................................................6

Annex B (informative) Sources of error and uncertainty of measurement when using a CMM..............7

Annex C (informative) Relation to the GPS matrix model ............................................................................................................12

Bibliography .............................................................................................................................................................................................................................14

© ISO 2013 – All rights reserved iii
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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. 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. 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.

The committee responsible for this document is ISO/TC 213, Dimensional and geometrical product

specifications and verification.

ISO 15530 consists of the following parts, under the general title Geometrical product specifications

(GPS) — Coordinate measuring machines (CMM): Technique for determining the uncertainty of measurement:

— Part 1: Overview and metrological characteristics [Technical Specification]
— Part 3: Use of calibrated workpieces or measurement standards

— Part 4: Evaluating task-specific measurement uncertainty using simulation [Technical Specification]

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Introduction

This part of ISO 15530 is a general GPS document which influences chain link 6 of the chain of standards

on size, distance, radius, angle, form, orientation, location, run-out and datums in the general GPS matrix.

The ISO/GPS masterplan given in ISO/TR 14638 gives an overview of the ISO/GPS system of which this

document is a part. The fundamental rules of ISO/GPS given in ISO 8015 apply to this document and

the default decision rules given in ISO 14253-1 apply to specifications made in accordance with this

document, unless otherwise indicated.

For more detailed information on the relation of this part of ISO 15530 to other standards and the GPS

matrix model, see Annex C.

It is the purpose of the ISO 15530 series to provide terminology, techniques and guidelines for estimating

task-specific measurement uncertainty when using coordinate measuring machines (CMMs). These

techniques allow for the evaluation of sources of uncertainty that affect a stated measurement, including

the influence of the coordinate measuring system, the sampling strategy, environmental effects, operator

variability and any other factors affecting the actual measurement result.

CMMs are considered to be complex GPS measuring equipment, and the estimation of the uncertainty

of CMM measurements often involves more advanced techniques than those described in ISO 14253-2.

The techniques presented in the ISO 15530 series are compliant with both ISO 14253-2 and

ISO/IEC Guide 98-3 (GUM). The techniques are developed specifically for CMMs but could be applied to

other GPS measuring equipment.

CMMs are specified by acceptance tests in the ISO 10360 series, which typically involve their ability

to measure calibrated lengths (e.g. volumetric tests using calibrated gauge blocks or step gauges) and

form (e.g. probing tests using a calibrated sphere). It is recognized that although these test results may

be used to determine an uncertainty for the specific types of length and form measurements involved

in these procedures, without further analysis or testing, these results are insufficient to determine the

task-specific measurement uncertainty of most workpiece measurements.

The goal of determining the measurement uncertainty can be achieved through many different

techniques; however, all methods must be consistent with ISO/IEC Guide 98-3, which yields a combined

standard uncertainty. The expanded uncertainty is connected to the combined standard uncertainty

via the coverage factor, which is selected to produce the desired level of confidence. The default value

for the coverage factor is two, i.e. k = 2, which yields a level of confidence of approximately 95 % if the

uncertainty is associated with a Gaussian distribution. It is the purpose of this document to provide

guidance on recognized techniques for the estimation of uncertainty of CMM measurements.

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SIST-TS CEN ISO/TS 15530-1:2014
TECHNICAL SPECIFICATION ISO/TS 15530-1:2013(E)
Geometrical product specifications (GPS) — Coordinate
measuring machines (CMM): Technique for determining
the uncertainty of measurement —
Part 1:
Overview and metrological characteristics
1 Scope

This part of ISO 15530 provides an overview of the ISO 15530 series. It discusses the metrological

characteristics of coordinate measuring machines (CMMs), the sources of task-specific uncertainty, and

the relationship between the ISO 10360 and ISO 15530 series.
2 Normative references

The following documents, in whole or in part, are normatively referenced in this document and are

indispensable for its application. For dated references, only the edition cited applies. For undated

references, the latest edition of the referenced document (including any amendments) applies.

ISO 10360-1:2000, Geometrical Product Specifications (GPS) — Acceptance and reverification tests for

coordinate measuring machines (CMM) — Part 1: Vocabulary

ISO 14253-1:— , Geometrical product specifications (GPS) — Inspection by measurement of workpieces and

measuring equipment — Part 1: Decision rules for proving conformity or nonconformity with specifications

ISO 14253-2:2011, Geometrical product specifications (GPS) — Inspection by measurement of workpieces

and measuring equipment — Part 2: Guidance for the estimation of uncertainty in GPS measurement, in

calibration of measuring equipment and in product verification

ISO 14978:2006, Geometrical product specifications (GPS) — General concepts and requirements for GPS

measuring equipment

ISO/IEC Guide 98-3, Uncertainty of measurement — Part 3: Guide to the expression of uncertainty in

measurement (GUM:1995)

ISO/IEC Guide 99, International vocabulary of metrology — Basic and general concepts and associated

terms (VIM)
3 Terms and definitions

For the purpose of this document, the terms and definitions given in ISO 10360-1, ISO 14253-1,

ISO 14253-2, ISO 14978, ISO/IEC Guide 98-3, ISO/IEC Guide 99 and the following apply.

3.1
task-specific measurement uncertainty

expanded uncertainty using a coverage factor of two (k = 2), evaluated according to ISO/IEC Guide 98-3,

of a specific measurement result

Note 1 to entry: Task-specific measurement uncertainty takes into account all uncertainty sources associated

with the details of the measurement process, including the CMM, probing system, sampling strategy, workpiece

location and orientation, fixturing, contamination, thermal environment.
1) To be published. (Revision of ISO 14253-1:1998)
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Note 2 to entry: Different parameters of a feature, in general, have different uncertainties, e.g. the X and Y ordinates

of the centre of a circle could have different uncertainties.

Note 3 to entry: Changing any influence quantity, e.g. the workpiece location in the CMM work zone, may change

the task-specific measurement uncertainty.
3.2
sampling strategy

number and spatial distribution of probing points used to measure a geometric feature

4 Metrological characteristics
4.1 General

Metrological characteristics of CMMs are of interest for the control of errors and uncertainty contributors

originating from the CMM and for the evaluation of uncertainty of measurement when using the CMM.

The influence of the individual metrological characteristics on the uncertainty of measurement is

dependent on the measurement process. The knowledge of the existence of the actual metrological

characteristics and the magnitude of their values may be the basis for the design of the measurement

process and the choice of the CMM.
4.2 Commerce

All metrological characteristics and their MPE (maximum permissible error) or MPL (maximum

permissible limit) values apply to the defined operating conditions of the specific CMM, e.g. probe

system qualification, speed of travel, etc. Operating conditions for CMMs are generally found in the

manufacturer’s operating manuals and specification data sheets and not normally in ISO standards.

All metrological characteristics and their MPE or MPL values apply to all possible orientations in

space, unless specific restrictions to the orientation are stated in the specific ISO standard or by the

manufacturer.

MPE or MPL values or functions for metrological characteristics for acceptance tests shall be supplied

by the manufacturer/supplier. The manufacturer may add additional information about metrological

characteristics and their MPE or MPL values.
4.3 Internal use in an organization

The customer shall identify and understand the major metrological characteristics by means of

uncertainty budgeting (for examples, see ISO 14253-2). Expert judgment and prior knowledge can be

used in the uncertainty estimation procedure. Calibration procedures can also be chosen based on

uncertainty budgets using expert judgment and prior knowledge.

MPE or MPL values or functions for metrological characteristics for internal calibrations and for

reverification tests shall be supplied by the user.
4.4 Identification, definition, and choice of metrological characteristics
4.4.1 Choice of metrological characteristics

Metrological characteristics of the CMM may be chosen and defined in several ways. Metrological

characteristics of the requirements (MPE and MPL) for these characteristics should preferably be chosen

and defined, including the necessary conditions, with respect to:
— common intended use of the CMM;
— independence of other metrological characteristics;
— the use in control of uncertainty contributors that relate to the CMM;
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— relevance to the physical principles inherent in the CMM;
— the use in maintenance activities and error identification;
— relation to specific parts or functions, or both, in the CMM;
— measuring principle;
— relevance of magnitude compared to other metrological characteristics.

It may be beneficial for a user of a CMM to define metrological characteristics other than those given in

the standards to better fit the needs and intended use of the CMM.
4.4.2 Metrological characteristics in ISO 10360

The metrological characteristics defined in various parts of ISO 10360, as specified by the MPE or MPL

values, could be considered in the choice of metrological characteristics for a CMM.

4.4.3 Machine geometry errors and residual error motion

The geometric error motions of the moving elements of a CMM, e.g. straightness, squareness, roll, pitch,

and yaw, can often be measured. CMMs often utilize some type of software compensation for these

geometric error motions; however, residual errors may exist and these errors could also be considered

in the choice for metrological characteristics for a CMM.
4.4.4 Organization-specific requirements

Organizations may have specific or unique measurement requirements that can result in the selection

of specific metrological characteristics to meet those requirements.
4.4.5 Other metrological characteristics

A list of possible metrological characteristics to consider for a CMM is included in Annex B. This list is

not exhaustive, though it can be considered rather complete.
4.5 Calibration of metrological characteristics

The necessary metrological characteristics for the intended use of the CMM should be chosen and verified

by calibration (or reverification tests.) The calibrated values of the metrological characteristics should

be stated with the related measurement uncertainty, and, where appropriate, the calibrated values of

the metrological characteristic should be proven to be in conformance with MPE values.

NOTE In the normal use of measuring instruments, it is often possible and proper to limit the number of

requirements (different MPEs) and the extent of resources used to prove that the measuring instrument is

functioning according to the setup requirements (MPLs and MPEs).
5 Task-specific uncertainty
5.1 General

Modern coordinate measurement systems, typically involving multi-axis CMMs, are affected by an

extraordinary range of uncertainty sources. Thus, a complete assessment of the uncertainty sources

and how they influence a specific measurement result can be a formidable task. For purposes of this

part of ISO 15530, three general uncertainty categories are described that encompass not only the CMM

itself but also the entire measurement process. An extensive list of potential uncertainty sources can be

found in Annex B.
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5.2 Instrumentation factors

Instrumentation factors include all errors that cause the measuring instrument, e.g. the CMM, to

inaccurately measure points in space. This may be due to geometrical errors in the machine structure

(both inherent to the manufacture of the CMM and those induced by dynamic effects, workpiece loading,

and the environment, i.e. temperature, vibration, etc.), errors in the probing system, and errors in other

sensor systems (temperature sensors, pressure sensors, etc.). Additionally, errors in the mathematical

formulation and execution of associated-feature-fitting algorithms supplied by the manufacturer for

data manipulation are included in this category. These factors are typically the responsibility of the

CMM manufacturer and are controlled by establishing permissible limits, e.g. temperature ranges, under

which the CMM may be used. Some or all of these error sources may be assessed during acceptance or

reverification testing of the CMM.
5.3 Measurement plan factors

Measurement plan factors involve how the CMM user decides to execute the measurement. This

includes the workpiece location and orientation, the probes and styli selected for the measurement,

and the particular measurement point sampling strategy. Additionally, the quantity being measured,

i.e. the measurand, shall be unambiguously specified. For example, in the case of a cylinder diameter

measurement, the user shall decide if a least-squares, minimum-circumscribed, maximum-inscribed

or minimum-zone result is desired. Some measurement plan factors may also influence the sensitivity

coefficients of other uncertainty components, for example the magnitude of a probe offset amplifies

CMM geometry errors.
5.4 Extrinsic factors

Extrinsic factors are often beyond the control of the CMM manufacturer and CMM user; nevertheless,

they affect the task-specific measurement uncertainty. They include non-ideal workpiece geometry (such

as surface roughness, form errors, finite stiffness and thermal distortions), contamination, workpiece

fixturing problems and variations among operators.
6 Techniques to determine task-specific measurement uncertainty components
6.1 General issues

To evaluate task-specific measurement uncertainty, the instrumentation, measurement plan and extrinsic

uncertainty sources shall be evaluated and combined in a manner consistent with ISO/IEC Guide 98-3.

Typically, several different evaluation techniques may be needed to include all sources. The various

uncertainty sources are then combined together using the law of propagation of uncertainty, yielding the

combined standard uncertainty. The combined standard uncertainty is then multiplied by the coverage

factor to yield the expanded uncertainty. The listing of the uncertainty sources, their combination, and

expression of the expanded uncertainty is known as the uncertainty budget.
6.2 Sensitivity analysis

This technique is described in ISO/IEC Guide 98-3. ISO 14253-2 is a simplified and iterative

implementation of this technique. Since CMMs are complex measuring instruments, directly

implementing this technique may only be possible for a limited number of measuring tasks. Essentially,

the technique consists of four steps.
a) List each uncertainty source to be included in the sensitivity analysis.

NOTE There are many different ways to separate uncertainty sources; hence, two equally valid

uncertainty budgets may have a different number of sources.

b) For each uncertainty source listed, quantify its magnitude by one standard deviation (known as the

standard uncertainty of the source).
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c) For each uncertainty source, determine its sensitivity coefficient and correlation with other

uncertainty sources, i.e. determine its influenc
...