SIST-TS CEN ISO/TS 15530-3:2008
(Main)Geometrical product specifications (GPS) - Coordinate measuring machines (CMM): Technique for determining the uncertainty of measurement - Part 3: Use of calibrated workpieces or standards (ISO/TS 15530-3:2004)
Geometrical product specifications (GPS) - Coordinate measuring machines (CMM): Technique for determining the uncertainty of measurement - Part 3: Use of calibrated workpieces or standards (ISO/TS 15530-3:2004)
This part of ISO 15530 specifies the evaluation of measurement uncertainty for results of measurements obtained by a CMM and by using calibrated workpieces. It provides an experimental technique for simplifying the uncertainty evaluation of CMM measurements, whose approach (substitution measurements) leads to measurements being carried out in the same way as actual measurements, but with calibrated workpieces of similar dimension and geometry instead of the unknown workpieces to be measured. Non-substitution measurements on CMMs are also covered, as are the requirements of the uncertainty evaluation procedure, the measurement equipment needed, and the reverification and the interim check of the measurement uncertainty.
NOTE The evaluation of measurement uncertainty is always related to a specific measuring task.
Geometrische Produktspezifikation (GPS) - Verfahren zur Ermittlung der Messunsicherheit von Koordinatenmessgeräten (KMG) - Teil 3: Anwendung von kalibrierten Werkstücken oder Normalen (ISO/TS 15530-3:2004)
Dieser Teil von ISO/TS 15530 legt die Ermittlung der Messunsicherheit für Ergebnisse von Messungen mit einem KMG unter Verwendung kalibrierter Werkstücke fest. Er bietet ein experimentelles Verfahren zur Vereinfachung der Unsicherheitsermittlung für Messungen mit KMG, dessen Ansatz (Substitutionsmessungen) dazu führt, dass Messungen in derselben Weise vorgenommen werden wie die eigentlichen Messungen, aber mit kalibrierten Werkstücken ähnlicher Abmessungen und Form anstelle der unbekannten zu messenden Werkstücke.
Messungen ohne Substitution auf KMG werden ebenfalls behandelt, sowie auch die Anforderungen des Verfahrens der Unsicherheitsermittlung, die benötigten Hilfsmittel, die Bestätigungsprüfung und die Zwischen¬prüfung der Messunsicherheit.
ANMERKUNG Die Ermittlung der Messunsicherheit bezieht sich immer auf eine bestimmte Messaufgabe.
Spécification géométrique des produits (GPS) - Machines a mesurer tridimentionnelles (MMT): Technique pour la détermination de l'incertitude de mesure - Partie 3: Utilisation de pieces étalonnées ou des normes (ISO/TS 15530-3:2004)
Specifikacija geometrijskih veličin izdelka - Koordinatni merilni stroji (CMM): postopek določevanja negotovosti meritev - 3. del: Uporaba kalibriranih izdelkov ali standardov (ISO/TS 15530-3:2004)
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST-TS CEN ISO/TS 15530-3:2008
01-april-2008
6SHFLILNDFLMDJHRPHWULMVNLKYHOLþLQL]GHOND.RRUGLQDWQLPHULOQLVWURML &00
SRVWRSHNGRORþHYDQMDQHJRWRYRVWLPHULWHYGHO 8SRUDEDNDOLEULUDQLKL]GHONRY
DOLVWDQGDUGRY ,6276
Geometrical product specifications (GPS) - Coordinate measuring machines (CMM):
Technique for determining the uncertainty of measurement - Part 3: Use of calibrated
workpieces or standards (ISO/TS 15530-3:2004)
Geometrische Produktspezifikation (GPS) - Verfahren zur Ermittlung der
Messunsicherheit von Koordinatenmessgeräten (KMG) - Teil 3: Anwendung von
kalibrierten Werkstücken oder Normalen (ISO/TS 15530-3:2004)
Spécification géométrique des produits (GPS) - Machines a mesurer tridimentionnelles
(MMT): Technique pour la détermination de l'incertitude de mesure - Partie 3: Utilisation
de pieces étalonnées ou des normes (ISO/TS 15530-3:2004)
Ta slovenski standard je istoveten z: CEN ISO/TS 15530-3:2007
ICS:
17.040.30 Merila Measuring instruments
SIST-TS CEN ISO/TS 15530-3:2008 en,fr
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST-TS CEN ISO/TS 15530-3:2008
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SIST-TS CEN ISO/TS 15530-3:2008
TECHNICAL SPECIFICATION
CEN ISO/TS 15530-3
SPÉCIFICATION TECHNIQUE
TECHNISCHE SPEZIFIKATION
December 2007
ICS 17.040.30
English Version
Geometrical product specifications (GPS) - Coordinate
measuring machines (CMM): Technique for determining the
uncertainty of measurement - Part 3: Use of calibrated
workpieces or standards (ISO/TS 15530-3:2004)
Spécification géométrique des produits (GPS) - Machines à Geometrische Produktspezifikation (GPS) - Verfahren zur
mesurer tridimentionnelles (MMT): Technique pour la Ermittlung der Messunsicherheit von
détermination de l'incertitude de mesure - Partie 3: Koordinatenmessgeräten (KMG) - Teil 3: Anwendung von
Utilisation de pièces étalonnées ou des normes (ISO/TS kalibrierten Werkstücken oder Normalen (ISO/TS 15530-
15530-3:2004) 3:2004)
This Technical Specification (CEN/TS) was approved by CEN on 8 October 2007 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, Cyprus, Czech Republic, Denmark, Estonia, Finland,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,
Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36 B-1050 Brussels
© 2007 CEN All rights of exploitation in any form and by any means reserved Ref. No. CEN ISO/TS 15530-3:2007: E
worldwide for CEN national Members.
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CEN ISO/TS 15530-3:2007 (E)
Contents Page
Foreword.3
2
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CEN ISO/TS 15530-3:2007 (E)
Foreword
The text of ISO/TS 15530-3:2004 has been prepared by Technical Committee ISO/TC 213 “Dimensional and
geometrical product specifications and verification” of the International Organization for Standardization (ISO)
and has been taken over as CEN ISO/TS 15530-3:2007 by 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, Cyprus, Czech
Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain,
Sweden, Switzerland and the United Kingdom.
Endorsement notice
The text of ISO/TS 15530-3:2004 has been approved by CEN as a CEN ISO/TS 15530-3:2007 without any
modification.
3
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SIST-TS CEN ISO/TS 15530-3:2008
TECHNICAL ISO/TS
SPECIFICATION 15530-3
First edition
2004-03-01
Geometrical Product Specifications
(GPS) — Coordinate measuring machines
(CMM): Technique for determining the
uncertainty of measurement —
Part 3:
Use of calibrated workpieces or
standards
Spécification géométrique des produits (GPS) — Machines à mesurer
tridimentionnelles (MMT): Technique pour la détermination de
l'incertitude de mesure —
Partie 3: Utilisation de pièces étalonnées ou des normes
Reference number
ISO/TS 15530-3:2004(E)
©
ISO 2004
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ISO/TS 15530-3:2004(E)
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ii © ISO 2004 – All rights reserved
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ISO/TS 15530-3:2004(E)
Contents Page
Foreword. iv
Introduction . v
1 Scope. 1
2 Normative references . 1
3 Terms and definitions. 1
4 Symbols . 2
5 Requirements . 2
5.1 Operating conditions . 2
5.2 Similarity conditions. 3
6 Principle of the uncertainty evaluation using calibrated workpieces . 4
7 Procedure. 4
7.1 Measuring equipment. 4
7.2 Execution . 4
7.3 Calculation of the uncertainty. 5
7.4 Applying the substitution method: special considerations . 8
8 Reverification of the measurement uncertainty. 9
9 Interim check of the measurement uncertainty . 9
Annex A (informative) Examples of application . 10
Annex B (informative) Relation to the GPS matrix model . 15
Bibliography . 16
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ISO/TS 15530-3:2004(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.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
In other circumstances, particularly when there is an urgent market requirement for such documents, a
technical committee may decide to publish other types of normative document:
— an ISO Publicly Available Specification (ISO/PAS) represents an agreement between technical experts in
an ISO working group and is accepted for publication if it is approved by more than 50 % of the members of
the parent committee casting a vote;
— an ISO Technical Specification (ISO/TS) represents an agreement between the members of a technical
committee and is accepted for publication if it is approved by 2/3 of the members of the committee casting a
vote.
An ISO/PAS or ISO/TS is reviewed after three years in order to decide whether it will be confirmed for a
further three years, revised to become an International Standard, or withdrawn. If the ISO/PAS or ISO/TS is
confirmed, it is reviewed again after a further three years, at which time it must either be transformed into an
International Standard or be withdrawn.
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.
ISO/TS 15530 was prepared by the Technical Committee ISO/TC 213, Dimensional and geometrical product
specifications and verification and consists of the following parts under the general title Geometrical Product
Specification (GPS) — Coordinate measuring machines (CMM) — Techniques for determining the uncertainty
of measurement:
Part 1: Overview and general issues
Part 2: Use of multiple measurement strategies
Part 3: Use of calibrated workpieces or standards
Part 4: Use of computer simulation
Part 5: Use of expert judgement
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ISO/TS 15530-3:2004(E)
Introduction
This part of ISO 15530 is a Geometrical Product Specification (GPS) Technical Specification and is to be
regarded as a general GPS document (see ISO/TR 14638). It influences chain link 6 of the chain of standards
on size, distance, radius, angle, form, orientation, location, run-out and datums.
For more detailed information on the relation of this standard to the GPS matrix model, see Annex B.
Coordinate measuring machines (CMMs) have become essential for the verification of geometry in industry.
According to the ISO 9000 series of standards, in a quality management system the relevant measuring
equipment is required to be calibrated against certified equipment having a known and valid relationship to
internationally or nationally recognized standards in order to establish traceability. According to the
International Vocabulary of Basic and General Terms in Metrology (VIM), a calibration comprises — besides
the establishment of the relationship between the measured and the correct values of a quantity — the
uncertainty evaluation in the final results (measurands) of the measurement task. However, uncertainty
evaluation methods covering the errors arising in the innumerable measurement tasks a CMM can actually
perform are often very complex. In these cases the risk of an unrealistic estimation of task-related uncertainty
is likely to arise.
The aim of this part of ISO 15530 is to provide an experimental technique for simplifying the uncertainty
evaluation of CMM-measurements. In this experimental approach measurements are carried out in the same
way as actual measurements, but with calibrated workpieces or standards of similar dimension and geometry
instead of the unknown objects to be measured. The description of this experimental technique to evaluate
measurement uncertainty is the key element of this part of ISO 15530. The standardization of such
procedures for the uncertainty evaluation serves the world-wide mutual recognition of calibrations and other
measurement results.
This part of ISO 15530 is applicable for non-substitution measurement of workpieces or standards, where the
measurement result is given by the indication of the CMM. Furthermore, this part of ISO 15530 is applicable
for substitution measurement, where, in opposition to the non-substitution measurement, a check standard is
used to correct for the systematic errors of the CMM. The latter will generally decrease the measurement
uncertainty and is often used, especially in the field of gauge calibration.
This part of ISO 15530 describes one of several methods of uncertainty evaluation, which will be outlined in
later ISO documents. Because of the experimental approach, it is simple to perform, and it provides realistic
statements of measurement uncertainties.
The limitations of this method can be summarised as: the availability of artefacts with sufficiently defined
geometrical characteristics, stability, reasonable costs, and the possibility of being calibrated with sufficiently
small uncertainty.
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SIST-TS CEN ISO/TS 15530-3:2008
TECHNICAL SPECIFICATION ISO/TS 15530-3:2004(E)
Geometrical Product Specifications (GPS) — Coordinate
measuring machines (CMM): Technique for determining the
uncertainty of measurement —
Part 3:
Use of calibrated workpieces or standards
1 Scope
This part of ISO 15530 specifies the evaluation of measurement uncertainty for results of measurements
obtained by a CMM and by using calibrated workpieces. It provides an experimental technique for simplifying
the uncertainty evaluation of CMM measurements, whose approach (substitution measurements) leads to
measurements being carried out in the same way as actual measurements, but with calibrated workpieces of
similar dimension and geometry instead of the unknown workpieces to be measured.
Non-substitution measurements on CMMs are also covered, as are the requirements of the uncertainty
evaluation procedure, the measurement equipment needed, and the reverification and the interim check of the
measurement uncertainty.
NOTE The evaluation of measurement uncertainty is always related to a specific measuring task.
2 Normative references
The following referenced documents are indispensable for the application 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 10360-1:2000, Geometrical Product Specifications (GPS) — Acceptance and reverification tests for
coordinate measuring machines (CMM) — Part 1: Vocabulary
International vocabulary of basic and general terms in metrology (VIM). BIPM, IEC, IFCC, ISO, IUPAC, IUPAP,
OIML, 2nd edition, 1993
Guide to the expression of uncertainty in measurement (GUM). BIPM, IEC, IFCC, ISO, IUPAC, IUPAP, OIML,
1st edition, 1993, corrected and reprinted in 1995
3 Terms and definitions
For the purpose of this part of ISO 15530, the terms and definitions given in ISO 10360-1, VIM and GUM, and
the following apply
3.1
non-substitution measurement
measurement where the uncorrected indication of the CMM is used as a result
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ISO/TS 15530-3:2004(E)
3.2
substitution measurement
measuring procedure where both a workpiece and a check standard are measured in order to provide
additional corrections for systematic errors of the CMM
4 Symbols
For the purpose of this part of ISO 15530, the symbols given in Table 1 apply.
Table 1 — Symbols
Symbol Interpretation
b Systematic error observed during the evaluation of the measurement uncertainty
Difference between the measured and calibrated values of the check standard when applying the
∆
i
substitution method
k Coverage factor
l Measured dimension
n Number of repeated measurements
T Average temperature of the workpiece or standard
u Standard uncertainty of the parameter of the calibrated workpiece or standard
cal
u Standard uncertainty of the measurement procedure
p
u Standard uncertainty resulting from the influences of the workpiece or standard
w
u Standard uncertainty of the expansion coefficient of the workpiece or standard
α
U Expanded measurement uncertainty
U Expanded uncertainty of the calibrated workpiece parameter
cal
x Value of the parameter of the calibrated workpiece or standard
cal
y Measurement result
y Measurement results during evaluation of measurement uncertainty
i
Uncorrected indications of the CMM during evaluation of measurement uncertainty when applying the
*
y
i
substitution method
y Mean value of the measurement result
5 Requirements
5.1 Operating conditions
Before starting the measurements, the CMM shall be initialized and procedures like probe configuration and
probe qualification shall be performed according to the conditions specified in the manufacturer’s operating
manual. In particular, an adequate thermal equilibrium of the (calibrated) workpiece or standard and the CMM
should exist.
For the measurements given in 7.2, the environmental and operational conditions quoted by the CMM
manufacturer and conditions quoted in the user's quality manual shall apply. In particular, existing error
compensating functions (like corrections applied via the software of the CMM’s computer) shall be active if this
is prescribed in the quality manual.
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ISO/TS 15530-3:2004(E)
The CMM shall fulfil the specifications of the manufacturer, or — if different — the specifications laid down in
the procedural instructions for the measurement task (task-related calibration, see ISO 14978), therefore, it is
not necessary to calibrate all the metrological characteristics of a CMM (global calibration, see ISO 14978).
5.2 Similarity conditions
The method requires similarity of the following.
a) The dimension and geometry of the workpiece or standard used in the actual measurements (see 7.2.1)
and the calibrated workpiece or standard used in the evaluation of measurement uncertainty (see 7.2.2).
NOTE Conditions to be reflected are, for example, positions and orientations.
b) The measurement procedure of the evaluation of measurement uncertainty and the actual measurement.
NOTE Conditions to be reflected are, for example, handling, exchange and clamping, time elapsed between
probing points, loading and unloading procedures, measuring force and speed.
c) The environmental conditions (including all variations) during evaluation of measurement uncertainty and
actual measurement.
NOTE Conditions to be reflected are, for example, temperature, temperature stabilisation time and temperature
corrections (if used).
In Table 2, the similarity requirements are given.
Table 2 — Similarity requirements for workpieces or standard to be measured and the calibrated
workpieces or standard used during evaluation of measurement uncertainty
Subject Requirements
Identical within:
10 % beyond 250 mm
Dimensions
Dimensional characteristics
25 mm below 250 mm
Angles Identical within ± 5°
Form deviations and surface texture Similar due to functional properties
Material (e.g. thermal expansion, elasticity, hardness) Similar due to functional properties
Measuring strategy Identical
Probe configuration Identical
The similarity of the thermal conditions are considered to be assured if the above requirements are met. The
evaluation of measurement uncertainty shall cover in particular the range of temperature which will prevail
during the actual measurement. If the variation of the thermal expansion coefficient of the measured
workpieces or standards is assumed as significant, this uncertainty contribution has to be taken into account
(see 7.3.2).
For some CMMs, errors associated with dynamic effects may become significant with decreasing probe
approach distance. For small internal features, e.g. a hole, the probe approach distance may be limited by the
feature size. Consequently, care shall be taken to ensure that the probe approach distance is identical.
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ISO/TS 15530-3:2004(E)
6 Principle of the uncertainty evaluation using calibrated workpieces
The evaluation of measurement uncertainty is a sequence of measurements, performed in the same way and
under the same conditions as the actual measurements. The only difference is that instead of the workpieces
to be measured, one or more calibrated workpieces are measured. The differences between the results
obtained by the measurement and the known calibration values of these calibrated workpieces are used to
estimate the uncertainty of the measurements.
The uncertainty of the measurement consists of uncertainty contributions:
a) due to the measurement procedure;
b) from the calibration of the calibrated workpiece;
c) due to the variations of the measured workpieces (changing form deviations, expansion coefficient and
surface texture).
The full effect of all variation in environmental conditions should be included, to perform a comprehensive
evaluation of the measurement uncertainty.
7 Procedure
7.1 Measuring equipment
The uncertainty evaluation on a CMM using calibrated workpieces requires the following equipment:
a) a task-related stylus set-up;
b) at least one calibrated workpiece.
The metrological characteristics of the calibrated workpieces shall be calibrated with a known and sufficiently
low uncertainty to fulfil the requirements of the measurement task.
NOTE The uncertainty stated for the calibration of the calibrated workpieces should be valid for the measurement
strategy employed during the actual measurements and the uncertainty evaluation.
7.2 Execution
7.2.1 General
The user of the CMM has a high degree of freedom to design the measurement procedure (i.e. the
measurement strategy) according to the technical requirements. This is possible, because the procedure and
conditions of actual measurements and those during the uncertainty evaluation shall be the same.
7.2.2 Actual measurement
One cycle of an actual measurement consists of the handling of the workpieces and one or more
measurements of the workpieces (see Figure 1).
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ISO/TS 15530-3:2004(E)
Figure 1 — Procedure of non-substitution measurement — Measuring cycle
The position and the orientation of the measured workpieces are free within the range covered by the
uncertainty evaluation.
7.2.3 Uncertainty evaluation
The uncertainty evaluation shall be as follows.
Calibrated workpieces are measured instead of the workpieces. Calibrated workpieces and workpieces shall
fulfill the similarity conditions outlined in 5.2. Special loading and unloading procedures shall be performed
during the uncertainty evaluation.
To obtain a sufficient number of samples for the uncertainty evaluation, at least 10 measurement cycles and a
total of at least 20 measurements on calibrated workpieces shall be carried out. This implies, e.g. a total of
20 cycles min., if only one calibrated workpiece per cycle is measured.
During the uncertainty evaluation, the position and orientation of the calibrated workpieces are systematically
varied within the limits given by the procedure of the actual measurements.
As specified in 7.2.1, a measuring cycle shall contain all actions involved in a real measurement to assure the
similarity of thermal conditions. This implies, e.g. that the CMM has to move through the same positions as if a
complete measurement were being carried out, even though during the uncertainty evaluation not all
workpieces may be present (dummy measurements).
7.3 Calculation of the uncertainty
7.3.1 General
In a calibration certificate or measurement report the measurement result, y, and its expanded uncertainty, U,
shall be expressed in the form y ± U, where U is determined with a coverage factor k = 2 for an approximated
coverage probability of 95 %.
When performing the measurements, basically three uncertainty contributions shall be taken into account,
described by the following standard uncertainties:
u standard uncertainty resulting from the uncertainty of the calibration of the calibrated workpiece
cal
stated in the calibration certificate;
u standard uncertainty resulting from the measurement procedure as assessed in the uncertainty
p
evaluation described below;
u standard uncertainty resulting from material and manufacturing variations (due to the variation of
w
expansion coefficient, form errors, roughness, elasticity and plasticity).
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ISO/TS 15530-3:2004(E)
In addition, a systematic error, b, may be considered separately.
The expanded measuring uncertainty, U, of any measured parameter is calculated from these standard
uncertainties as:
222
Uk=× u +u +u +b
cal p w
The coverage factor, k, is recommended to be chosen as k = 2 for a coverage probability of 95 %.
In Table 3, the uncertainty contributions for the measurement are listed.
Table 3 — The uncertainty components and their consideration in the uncertainty assessment
Method of evaluation
Uncertainty component Designation
(according to GUM)
Geometrical errors of CMM
Temperature of CMM
Drift of CMM
Temperature of workpiece
Systematic errors of probing system
Repeatability of the CMM
assessed in a sum
Scale resolution of the CMM A
u
P
Temperature gradients of the CMM
Random errors of the probing system
Probe changing uncertainty
Errors induced by the procedure (clamping, handling, etc.)
Errors induced by dirt
Errors
...
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