Geometrical product specifications (GPS) - Decomposition of geometrical characteristics for manufacturing control (ISO 20170:2019)

This document describes principles and tools to control a manufacturing process in accordance with a GPS specification. For this purpose a set of one or more complementary, independent characteristics (size, form, orientation, and location characteristics independent to each other) that correlate to the manufacturing process parameters and to the manufacturing process coordinate system established from the manufacturing datum system are used.
This document describes the concept of decomposition of the macro-geometrical part of the GPS specification. It does not cover the micro-geometry, i.e. surface texture.
The objective of the decomposition presented in this document is to define correction values for manufacturing control or to perform a statistical analysis of the process.

Geometrische Produktspezifikation (GPS) - Zerlegung von geometrischen Merkmalen für die Fertigungskontrolle (ISO 20170:2019)

Dieses Dokument beschreibt Grundsätze und Werkzeuge zur Kontrolle eines Fertigungsprozesses in Übereinstimmung mit einer GPS-Spezifikation. Zu diesem Zweck wird ein Satz aus einem oder mehreren komplementären und unabhängigen Merkmalen (Größenmaß, Form, Richtungs- und Ortsmerkmale unabhängig voneinander) verwendet, die mit den Parametern des Fertigungsprozesses und mit dem Fertigungskoordinatensystem, das aus dem Fertigungsbezugssystem abgeleitet ist, korrelieren.
Dieses Dokument beschreibt das Konzept der Dekomposition des makrogeometrischen Teils der GPS-Spezifikation. Es deckt nicht die Mikrogeometrie, d. h. die Oberflächenbeschaffenheit, ab.
Das Ziel der in diesem Dokument vorgestellten Dekomposition ist, Korrekturwerte für die Fertigungs-prozesssteuerung festzulegen oder eine statistische Analyse des Prozesses durchzuführen.

Spécification géométrique des produits (GPS) - Décomposition des caractéristiques géométriques pour la maîtrise de la fabrication (ISO 20170:2019)

Le présent document décrit les principes et outils nécessaires pour maîtriser un processus de fabrication conformément à une spécification GPS. A cet effet, on utilise un ensemble d'une ou plusieurs caractéristiques indépendantes complémentaires (taille, forme, orientation et caractéristiques de position, indépendantes les unes des autres), qui sont corrélées avec les paramètres du processus de fabrication et le système de coordonnées du processus de fabrication établi à partir du système de références, est utilisé à cet effet.
Le présent document décrit le concept de décomposition de la partie macro-géométrique de la spécification GPS. Il ne traite pas de la micro-géométrie, c'est-à-dire de l'état de surface.
L'objectif de la décomposition présentée dans le présent document est de définir les valeurs de correction pour maîtriser la fabrication ou réaliser une analyse statistique du processus.

Specifikacija geometrijskih veličin izdelka (GPS) - Razčlenitev geometrijskih lastnosti za kontrolo proizvodnje (ISO 20170:2019)

Ta standard opisuje načela in orodja za kontrolo proizvodnega procesa v skladu s specifikacijo GPS. Določa, da rezultat specifikacije GPS, ki je sestavljen iz ene vrednosti, ne zadostuje za kontrolo proizvodnega procesa. Za ta namen je treba uporabiti nabor ene ali več komplementarnih, neodvisnih lastnosti, ki so povezane s parametri proizvodnega procesa.  Ta standard opisuje koncept razčlenitve makro-geometrijskega dela specifikacije GPS. Ne obsega mikro-geometrije, tj. teksture površine.  Cilj razčlenitve, predstavljene v tem standardu, je opredeliti korekcijske vrednosti za kontrolo proizvodnje ali izvesti statistično analizo postopka.

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Publication Date
14-May-2019
Current Stage
6060 - Definitive text made available (DAV) - Publishing
Due Date
15-May-2019
Completion Date
15-May-2019

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SLOVENSKI STANDARD
SIST EN ISO 20170:2019
01-julij-2019
Specifikacija geometrijskih veličin izdelka (GPS) - Razčlenitev geometrijskih
lastnosti za kontrolo proizvodnje (ISO 20170:2019)

Geometrical product specification (GPS) - Decomposition of geometrical characteristics

for manufacturing control (ISO 20170:2019)

Geometrische Produktspezifikation (GPS) - Zerlegung von geometrischen Merkmalen für

die Fertigungskontrolle (ISO 20170:2019)

Spécification géométrique des produits (GPS) - Décomposition des caractéristiques

géométriques pour le contrôle en fabrication (ISO 20170:2019)
Ta slovenski standard je istoveten z: EN ISO 20170:2019
ICS:
17.040.40 Specifikacija geometrijskih Geometrical Product
veličin izdelka (GPS) Specification (GPS)
SIST EN ISO 20170:2019 en,fr,de

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

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SIST EN ISO 20170:2019
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SIST EN ISO 20170:2019
EN ISO 20170
EUROPEAN STANDARD
NORME EUROPÉENNE
May 2019
EUROPÄISCHE NORM
ICS 17.040.01; 17.040.40
English Version
Geometrical product specifications (GPS) - Decomposition
of geometrical characteristics for manufacturing control
(ISO 20170:2019)

Spécification géométrique des produits (GPS) - Geometrische Produktspezifikation (GPS) - Zerlegung

Décomposition des caractéristiques géométriques pour von geometrischen Merkmalen für die

la maîtrise de la fabrication (ISO 20170:2019) Fertigungskontrolle (ISO 20170:2019)

This European Standard was approved by CEN on 19 February 2019.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this

European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references

concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN

member.

This European Standard exists in three official versions (English, French, German). A version in any other language made by

translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management

Centre has the same status as the official versions.

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, Serbia, 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: Rue de la Science 23, B-1040 Brussels

© 2019 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 20170:2019 E

worldwide for CEN national Members.
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SIST EN ISO 20170:2019
EN ISO 20170:2019 (E)
Contents Page

European foreword ....................................................................................................................................................... 3

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SIST EN ISO 20170:2019
EN ISO 20170:2019 (E)
European foreword

This document (EN ISO 20170:2019) 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.

This European Standard shall be given the status of a national standard, either by publication of an

identical text or by endorsement, at the latest by November 2019, and conflicting national standards

shall be withdrawn at the latest by November 2019.

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

patent rights. CEN 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 implement this European Standard: 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, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,

Turkey and the United Kingdom.
Endorsement notice

The text of ISO 20170:2019 has been approved by CEN as EN ISO 20170:2019 without any modification.

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SIST EN ISO 20170:2019
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SIST EN ISO 20170:2019
INTERNATIONAL ISO
STANDARD 20170
First edition
2019-04
Geometrical product specifications
(GPS) — Decomposition of
geometrical characteristics for
manufacturing control
Spécification géométrique des produits (GPS) — Décomposition des
caractéristiques géométriques pour la maîtrise de la fabrication
Reference number
ISO 20170:2019(E)
ISO 2019
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SIST EN ISO 20170:2019
ISO 20170:2019(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2019

All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may

be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting

on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address

below or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Fax: +41 22 749 09 47
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii © ISO 2019 – All rights reserved
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SIST EN ISO 20170:2019
ISO 20170:2019(E)
Contents Page

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

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

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

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

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

4 Symbols .......................................................................................................................................................................................................................... 3

5 Principles ..................................................................................................................................................................................................................... 3

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

5.2 Decomposition process ................................................................................................................................................................... 4

5.3 Determination of components of a collected characteristic .........................................................................12

5.4 Use of collected characteristics ..............................................................................................................................................13

5.5 Presentation of a GPS or a collected characteristic results ............................................................................14

5.5.1 General...................................................................................................................................................................................14

5.5.2 Decomposition steps .................................................................................................................................................15

Annex A (informative) Relationship to the ISO GPS matrix model .....................................................................................19

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

© ISO 2019 – All rights reserved iii
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SIST EN ISO 20170:2019
ISO 20170:2019(E)
Foreword

ISO (the International Organization for Standardization) is a worldwide federation of national standards

bodies (ISO member bodies). The work of preparing International Standards is normally carried out

through ISO technical committees. Each member body interested in a subject for which a technical

committee has been established has the right to be represented on that committee. International

organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.

ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of

electrotechnical standardization.

The procedures used to develop this document and those intended for its further maintenance are

described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the

different types of ISO documents should be noted. This document was drafted in accordance with the

editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/directives).

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

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

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

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

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

constitute an endorsement.

For an explanation of 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 213, Dimensional and geometrical product

specifications and verification.

Any feedback or questions on this document should be directed to the user’s national standards body. A

complete listing of these bodies can be found at www .iso .org/members .html.
iv © ISO 2019 – All rights reserved
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SIST EN ISO 20170:2019
ISO 20170:2019(E)
Introduction

This document is a geometrical product specifications (GPS) standard and is to be regarded as a

fundamental GPS standard (see ISO 14638). It influences indirectly chain link E of the chains of

standards of geometrical characteristic (size, distance, form, orientation, location and run-out) in

the general GPS matrix model as graphically illustrated in Table A.1. The measurement as given in

chain link E is decomposed to evaluate quantity values of a geometrical characteristic, and to define

manufacturing adjustment values, not to manage the conformance of a workpiece.

The ISO GPS matrix model given in ISO 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 relationship of this document to other standards and to the GPS

matrix model, see Annex A.

The geometrical specification, as defined in ISO 1101, allows the evaluation of conformance or non-

conformance by defining a limit value for a geometrical characteristic as a univariate characteristic

(non-signed value). This evaluation alone does not provide the information necessary to adjust machine

tools parameters to maintain the production of conforming workpieces. The goal of decomposition of

the measurement result is to isolate parameter values that can be used to adjust the manufacturing

process. This document uses simple examples to illustrate the fundamental principles.

This document defines a number of independent characteristics obtained by decomposition that are

intended to assist with adjusting and evaluating the manufacturing process.

In statistical analysis the mean value and standard deviation are used to calculate capability indices. In

the case of a position tolerance, for example the location of a hole, which applies in a plane perpendicular

to the axis of the hole, the position characteristic is two times the radial distance between the centre of

the hole and its theoretically exact location. Capability indices based on the mean value and standard

deviation of this characteristic do not properly reflect the capability of a manufacturing process.

Instead, the position characteristic could be decomposed according to the kinematic arrangement of

the manufacturing process. If the axis of the hole is manufactured using a machine with linear X- and

Y-axes, the position characteristic could be decomposed into an X-component and a Y-component and

the studies of capability could be calculated based on these components so that they properly reflect

the capability of the manufacturing process.
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SIST EN ISO 20170:2019
INTERNATIONAL STANDARD ISO 20170:2019(E)
Geometrical product specifications (GPS) —
Decomposition of geometrical characteristics for
manufacturing control
1 Scope

This document describes principles and tools to control a manufacturing process in accordance with

a GPS specification. For this purpose a set of one or more complementary, independent characteristics

(size, form, orientation, and location characteristics independent to each other) that correlate to the

manufacturing process parameters and to the manufacturing process coordinate system established

from the manufacturing datum system are used.

This document describes the concept of decomposition of the macro-geometrical part of the GPS

specification. It does not cover the micro-geometry, i.e. surface texture.

The objective of the decomposition presented in this document is to define correction values for

manufacturing control or to perform a statistical analysis of the process.
2 Normative references
There are no normative references in this document.
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.

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

— ISO Online browsing platform: available at https: //www .iso .org/obp
— IEC Electropedia: available at http: //www .electropedia .org/
3.1
univariate characteristic
characteristic represented by a single scalar variable
EXAMPLE A global size characteristic is a univariate characteristic.
3.2
collected characteristic

set of a univariate characteristic (3.1) and the multivariate characteristic required to derive it (see 3.3)

EXAMPLE For a position specification, the median line of a hole is constrained by a cylindrical tolerance

zone with a diameter of 0,4 mm. The global univariate characteristic result is 0,5 mm (out of tolerance). The

decomposition of the location in two directions (X, Y) at a given height is given by the multivariate characteristic

result (+0,15; +0,2). The collected characteristic combines the global result and its decomposition.

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SIST EN ISO 20170:2019
ISO 20170:2019(E)
Result of evaluation
Univariate characteristic 0,5
Observed deviation 0,25
Collected characteristic
X +0,15
Multivariate deviations
Y +0,2

Note 1 to entry: A collected characteristic is a set of more than one independent variable and the final result from

this set of variables, e.g. C (A, G , G , G , R , R , R , G , T , T , T ). See Table 1 for an example.

F S O X Y Z L X Y Z
Note 2 to entry: A collected characteristic is a vector.
3.3
decomposition

operation establishing a multivariate characteristic from a univariate GPS

characteristic (3.1)

Note 1 to entry: The purpose of the decomposition for manufacturing is to define a multivariate characteristic

that consists of a set of variables, each of which is related to a manufacturing process parameter (See 5.2).

3.4
location point
defined point on the reference feature used to locate a geometrical feature
3.5
real orientation vector

unit vector defining the orientation of the extracted feature from the situation feature of the associated

feature in a specified Cartesian system
3.6
nominal orientation vector

unit vector defined from the situation feature of the nominal feature in a specified Cartesian system

3.7
angular deviation set

vector having components which are the angles defined in a specified Cartesian system allowing the

transformation of the real orientation vector (3.5) into the nominal orientation vector (3.6)

3.8
actual location vector

vector defining the location of the extracted feature from the origin of a specified Cartesian system to

the location point (3.4) of the situation feature of the associated integral feature

3.9
theoretical location vector

vector defined from the origin of a specified Cartesian system to a location point of a situation feature

of the nominal geometrical feature (integral, or derived)
2 © ISO 2019 – All rights reserved
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3.10
deviation location vector

vector defined as the difference between the actual location vector (3.8) and the theoretical location

vector (3.9)

Note 1 to entry: The components of the deviation location vector defined on the X-axis, Y-axis, and Z-axis of the

specified Cartesian system are designated as T , T , T .
X Y Z.
4 Symbols
The list of symbols is given in Table 1.
Table 1 — Symbols
Symbol Description
C Generic symbol of a collected characteristic, which is a vector
A Actual value of the specified GPS characteristic
O Actual value of the orientation GPS characteristic
G Independent form characteristic
G Independent global size characteristic

G Independent orientation characteristic, corresponding to the effect of the angular deviation (R , R , R ) in length unit

O x y z

by considering the orientation deviation defined from the restricted associated feature

G Independent location characteristic, corresponding to the effect of the linear deviation (T , T , T ) considering the loca-

L x y z

tion deviation of the reference feature of the orientation characteristic from the theoretically exact location

V Real orientation vector for the extracted feature in the coordinate system
V Nominal orientation vector for the nominal feature in the coordinate system

V Angular deviation set from the theoretically exact orientation in the coordinate system

V Actual location vector for a specific point defined from extracted feature in the coordinate system

V Theoretical location vector for a specific point defined on the nominal feature in the coordinate system

V Deviation location vector from the theoretically exact location in the coordinate system

R , R , R Rotation angle components around axes of the coordinate system
X Y Z

T , T , T Components of V which are the translation deviations from the theoretically exact location of the location point

X Y Z ΔL

NOTE A geometrical GPS characteristic is defined in ISO 25378 as a “zone characteristic”.

5 Principles
5.1 General

A GPS specification is a condition (a tolerance) applied on a univariate characteristic.

In particular for a geometrical tolerance, this characteristic can include several types of independent

deviations (size, form, orientation and location) and other kinds of deviation parameters (angle

deviations, location deviations). To control the manufacturing process, these deviations shall be

separated. This document presents a way to perform this separation for a geometrical specification,

giving inputs to corrections to manufacturing process parameters. The decomposition of a GPS

characteristic yields the components of the collected characteristic. These shall be measurable

quantities. These components can be independent GPS characteristics (form, size, orientation and

location) or components from which rotation or translation parameters reflecting the kinematics of the

manufacturing process can be derived.

Typically, the univariate characteristic of a GPS specification is defined from a set of distances between

an input feature (the toleranced feature) and a reference feature or a set of sizes. This definition is the

primary model of decomposition for the GPS specification, having these n distances as the independent

variables. Therefore if the specification is verified on a feature using for example 1 000 points on the

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surface, this primary model of decomposition would result in 1 000 distances. However, these 1 000

distances cannot be used directly for manufacturing process corrections.

Three geometrical features shall be distinguished in this kind of operation: the extracted feature, its

associated feature and the situation feature of the associated feature.
5.2 Decomposition process

The first step of the decomposition is to define the default form GPS characteristic of the toleranced

feature (integral or derived), G [see Figure 2 d), Figure 3 d) and Figure 4 d)]. If the associated features

are established by another association criteria than the default criteria (minimax – Chebyshev) then it

shall be stated in the report of results of decomposition.

NOTE The curve variation of form deviation can itself be analysed by decomposition (e.g. by Fourier

analysis or modal discrete decomposition). It is not the intent of this document to describe this process of form

decomposition.

To separate the signed orientation and location parameters, a coordinate system, for example a

Cartesian system or a polar system, shall be defined for manufacturing purpose from the datum system

attached to the manufacturing process. If the specification datum system does not lock all degrees of

freedom, it shall be complemented by a secondary datum and/or a tertiary datum defined from the

workpiece interface surfaces with the manufacturing machine.

The orientation parameters (R , R , R ) expressed by V , shall be given in angular units.

X Y Z ΔΟ

The form characteristic (G ), the independent size characteristic (G ), the independent orientation

F S

characteristic (G ), the location parameters (T , T , T ) and the independent location characteristic

O X Y Z
(G ) shall be given in linear (length) unit.

The independent size characteristic, (G ), only applies to features of size or to a non-feature of size on

which an offset can be applied and which changes its nominal shape. For a feature of size, it is defined

as the difference between the size of the direct associated integral feature and the nominal size. For a

non-feature of size on which an offset can be applied, the size deviation parameter defines the observed

offset from the nominal shape.

The direction vector of the form reference feature allows establishing the transfer angles (R , R ,

X Y

R ) from the geometrical specification Cartesian system. The relation between the manufacturing

Cartesian system and the geometrical specification Cartesian system is used to define the correction

to the manufacturing process. To evaluate the independent characteristic, the restricted associated

feature shall be established by projecting the extracted feature onto the form reference feature.

The orientation reference feature is defined from the restricted associated feature. The independent

orientation characteristic, (G ), is evaluated as an orientation characteristic established from the

restricted associated feature (corresponding to the extracted feature, see Figure 2 e), Figure 3 e), and

Figure 4 e). The independent orientation characteristic can be decomposed in three angles (R , R , R ).

X Y Z

The independent location characteristic, (G ), is the signed distance between the location reference

feature and the orientation reference feature, at the location point (considered on the location reference

feature). The independent location characteristic shall be described in the manufacturing Cartesian

system. By default, it is the distance between the location point (belonging to the orientation reference

feature) and its theoretical exact location (see Figure 4 f).

The independent location characteristic can be decomposed in three linear components (T , T , T ).

X Y Z

Figure 1 a) presents a geometrical specification with datum system where the manufacturing datum

system is considered identical to the specified datum system. Figure 1 b) illustrates the manufacturing

result: the workpiece. Figures 1 c) to f) illustrate steps of the decomposition process of a specified

geometrical characteristic.
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ISO 20170:2019(E)
a) GPS specification b) Workpiece

c) Step 1: datum system and Cartesian system d) Step 2: independent form and size character-

(see Note 1) istics (see Note 2)

e) Step 3: independent orientation character- f) Step 4: independent location characteristic

istic (see Note 3) (see Note 4)
NOTE 1 To determine the collected characteristic (see Table 4):

— the univariate characteristic is the result of the evaluation of GPS location specification.

— the multivariate characteristic is the result of the decomposition, i.e. the set of independent size, form,

orientation, and location characteristic evaluations.

NOTE 2 After a first association, the evaluation of the size deviation parameter and of the form deviation is

considered independently.

NOTE 3 The evaluation of the angular deviations is established from the situation feature of the previous

associated feature from the datum A.
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NOTE 4 The evaluation of the location deviations is established from the considered location point of the

situation feature from the datum system A, B, C.

Figure 1 — Steps of manufacturing decomposition to geometrical specifications in macro

geometry

Examples 1 to 3 and Figures 2 to 4 present and illustrate the components of collected characteristics

for orientation specification or location specification.

EXAMPLE 1 A parallelism orientation characteristic applied in an intersection plane can be seen as a collected

characteristic combining the form deviation and the angular deviation of the extracted integral line as shown in

Figure 2, when it is assumed that the manufacturing fixture surface and datum feature K are the same.

a) GPS specification b) GPS orientation characteristic evaluation: A
NOTE L: Complementary datum feature used to
establish the Cartesian system ( X, Y, Z).

c) Introduction of Cartesian system and at- d) Independent form characteristic evalua-

tached complementary datum tion: G
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NOTE In the case of orientation GPS characteristic, O is equal to A [distance between 3)].

e) Independent orientation characteristic: G [distance between 12)]
Key
A GPS characteristic of parallelism 5 normal vector from 2)
O actual value of orientation GPS characteristic (in this 6 datum K
case O = A)
G GPS characteristic of form 7 datum feature K
G independent orientation characteristic 8 normal vector from 6)
R angle deviation around Z-axis 9 limits of minimum zone for form

1 toleranced feature: extracted integral surface 10 restricted associated feature, restricted by the

2 reference feature of 1) for orientation GPS projection of 1) on the medi
...

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