ISO 10303-204:2002

INTERNATIONAL ISO
STANDARD 10303-204
First edition
2002-08-15


Industrial automation systems and
integration — Product data representation
and exchange —
Part 204:
Application protocol: Mechanical design
using boundary representation
Systèmes d'automatisation industrielle et intégration — Représentation
et échange de données de produits —
Partie 204: Protocole d'application: Conception mécanique utilisant une
représentation délimitée





Reference number
ISO 10303-204:2002(E)
©
 ISO 2002

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ISO 10303-204:2002(E)
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ISO 10303-204:2002(E)
Contents Page
1 Scope . . . . . 1
2 Normativereferences . . . . 3
3 Terms,definitions,andabbreviations . . . . 5
3.1 Terms defined in ISO 10303-1 . . . . 5
3.2 Terms defined in ISO 10303-42 . . . 6
3.3 Terms defined in ISO 10303-44 . . . 6
3.4 Otherdefinitions . . . . 7
3.5 Abbreviations. . . . 8
4 Informationrequirements . . . . 9
4.1 Units of functionality . . . . 11
4.1.1 faceted_B-rep . . . . 12
4.1.2 elementary_B-rep . . . . 13
4.1.3 advanced_B-rep . . . . 14
4.1.4 name_preservation . . . . 16
4.1.5 product_structure. . . . 16
4.1.6 visual_presentation_for_B-rep . . . 17
4.2 Applicationobjects . . . . 18
4.3 Applicationassertions . . . . 34
5 Applicationinterpretedmodel . . . . 38
5.1 Mappingtable . . . . 38
5.2 AIMEXPRESSshortlisting . . . . . 67
6 Conformancerequirements . . . . 93
6.1 Conformanceclass1:B-replevel1(CC1) . . . 94
6.2 Conformanceclass2:B-replevel2(CC2) . . . 94
6.3 Conformanceclass3:B-replevel3(CC3) . . . 95
AnnexA(normative) AIMEXPRESSexpandedlisting . . . . 97
A.1 AIMEXPRESSlisting . . . . 97
AnnexB(normative) AIMshortnames. . . 185
AnnexC(normative) Implementationmethodspecificrequirements . . 192
Annex D (normative) PICS (Protocol Implementation Conformance Statement) proforma . . 193
AnnexE(normative) Informationobjectregistration . . . 195
E.1 Documentidentification . . . . 195
E.2 Schemaidentification. . . . 195
AnnexF(informative) ApplicationActivityModel(AAM) . . . 196
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ISO 10303-204:2002(E)
F.1 AAMdefinitions . . . . 196
F.2 DescriptionofAAMscenario . . . . 200
F.3 Mechanicaldesignrequirementsformodelcontentsandcompleteness . . . 203
F.4 AAMdiagrams . . . . 206
AnnexG(informative) Applicationreferencemodeldiagrams . . 211
AnnexH(informative) AIMEXPRESS-G . . . 224
AnnexJ(informative) Computerinterpretablelisting . . . 243
AnnexK(informative) Technicaldiscussions . . . 244
K.1 Geometricshapedescriptionalternatives. . . 244
K.2 Knownissues . . . . 244
Bibliography . . . . . 246
Index . . . . . 247
Figures
Figure 1 The scope of this part of ISO 10303 in the contexts of CAD models and mechanical
engineeringapplications . . . . ix
Figure2 Dataplanningmodel . . . . x
Figure3 RelationshipsbetweengeometricAICs. . . 40
Figure F.1 Conceptual structure of mechanical design product . . 205
Figure F.2 Industrial manufacturing of mechanical products (node A0) . . 207
Figure F.3 Industrial manufacturing of mechanical products (node A0 expanded) . 208
Figure F.4 Conceptual design (node A3) . . . 209
FigureF.5 Designandevaluation(NodeA4). . . 210
FigureG.1 ARMdiagram(1of12) . . . . 212
FigureG.2 ARMdiagram(2of12) . . . . 213
FigureG.3 ARMdiagram(3of12) . . . . 214
FigureG.4 ARMdiagram(4of12) . . . . 215
Figure G.5 ARM diagram (5 of 12) shell in faceted B-rep . . . . 216
FigureG.6 ARMdiagram(6of12)shellinelementaryoradvanced_B-rep . . 217
FigureG.7 ARMdiagram(7of12)surfaceinadvancedB-rep. . 218
FigureG.8 ARMdiagram(8of12)surfaceinelementaryB-rep. . 219
FigureG.9 ARMdiagram(9of12)curveinadvanced_B-rep . . 220
FigureG.10 ARMdiagram(10of12)curveinelementary_B-rep . . 221
FigureG.11 ARMdiagram(11of12) . . . . 222
FigureG.12 ARMdiagram(12of12)conventionsusedinNIAMdiagrams . . 223
FigureH.1 AIMEXPRESS-GdiagramadvancedB-rep . . . 225
FigureH.2 AIMEXPRESS-Gdiagramadvanced_face. . . 226
Figure H.3 AIM EXPRESS-G diagram surfaces . . . 227
FigureH.4 AIMEXPRESS-Gdiagramcurves . . . 228
FigureH.5 AIMEXPRESS-Gdiagramelementary_surface . . . 229
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ISO 10303-204:2002(E)
FigureH.6 AIMEXPRESS-Gdiagramb_spline_curve . . . 230
FigureH.7 AIMEXPRESS-Gdiagramb_spline_surface . . . 231
FigureH.8 AIMEXPRESS-Gdiagramsurfacecurves . . . 232
FigureH.9 AIMEXPRESS-GdiagramelementaryB-rep . . . . 233
FigureH.10 AIMEXPRESS-GdiagramfaceandcurveinelementaryB-rep . . 234
Figure H.11 AIM EXPRESS-G diagram faceted B-rep . . . 235
Figure H.12 AIM EXPRESS-G diagram product structure . . . . 236
Figure H.13 AIM EXPRESS-G diagram product structure continued . . 237
FigureH.14 AIMEXPRESS-Gdiagramvisualpresentation . . . 238
FigureH.15 AIMEXPRESS-Gdiagramcameramodelandprojection . . 239
FigureH.16 AIMEXPRESS-Gdiagrampointandcurvestyles . . 240
FigureH.17 AIMEXPRESS-Gdiagramsurfacestyles . . . 241
FigureH.18 AIMEXPRESS-Gdiagramvisualpresentationconcluded. . 242
Tables
Table 1 Use of units of functionality within functional levels. . 18
Table2 Mappingtableforadvanced_B-repUoF . . . 41
Table3 Mappingtableforelementary_B-RepUoF . . . 48
Table 4 Mapping table for faceted_B-Rep UoF . . . 52
Table5 Mappingtableforname_preservationUoF . . . 54
Table 6 Mapping table for product_structure UoF . . . 55
Table 7 Mapping table for visual_presentation_for_B-rep UoF . . 59
Table 8 Units of functionality within conformance classes . . 94
Table 9 AIM entities within conformance classes. . . 96
Table B.1 AIM short names of entities . . . . 185
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ISO 10303-204:2002(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 com-
mittee 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 stan-
dardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 3.
The main task of technical committees is to prepare International Standards. Draft International Stan-
dards 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.
Attention is drawn to the possibility that some of the elements of this part of ISO 10303 may be the
subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights.
International Standard ISO 10303-204was prepared by Technical Committee ISO TC184/SC4. Industrial
automation systems and integration, Subcommittee SC4 Industrial data.
This International Standard is organised as a series of parts, each published separately. The structure of
this International Standard is decribed in ISO 10303-1.
Each part of this International Standard is a member of one of the following series: decription meth-
ods, implementation methods, conformance testing methodology and framework, integrated generic re-
sources, integrated application resources, application protocols, abstract test suites, application inter-
preted constructs, and application modules. This part is a member of the application protocol series.
A complete list of parts of ISO 10303 is available from Internet:

Annexes A, B, C, D and E form an integral part of this part of ISO 10303. Annexes F, G, H, J and K are
for information only.
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ISO 10303-204:2002(E)
Introduction
ISO 10303 is an International Standard for the computer-interpretable representation and exchange of
product data. The objective is to provide a neutral mechanism capable of describing products throughout
their life cycle. This mechanism is suitable not only for neutral file exchange, but also as a basis for
implementing and sharing product databases and as a basis for archiving.
This part of ISO 10303 is a member of the application protocol series.
This Part of ISO 10303 specifies an application protocol (AP) for mechanical design using boundary
representation solid models. A boundary representation solid model provides a complete descripton of
the shape of a solid object by describing precisely the geometry and topology of all its internal and
external boundaries.
This application protocol defines the context, scope, and information requirements for mechanical design
using boundary representation models and specifies the integrated resources necessary to satisfy these
requirements.
Application protocols provide the basis for developing implementations of ISO 10303. Application
protocols provide the basis for developing abstract test suites for the conformance testing of AP imple-
mentations.
Clause 1 defines the scope of the application protocol and summarizes the functionality and data covered
by the AP. An application activity model that is the basis for the definition of the scope is provided in
annex F. The information requirements of the application are specified in clause 4 using terminology
appropriate to the application. A graphical representation of the information requirements, referred to as
the application reference model, is given in annex G.
Resource constructs are interpreted to meet the information requirements. This interpretation produces
the application interpreted model (AIM). This interpretation, given in 5.1, shows the correspondence
between the information requirements and the AIM. The short listing of the AIM specifies the interface
to the integrated resources and is given in 5.2. note that definitions and the EXPRESS provided in
the integrated resources for constructs used in the AIM may include select list items and subtypes not
imported into the AIM. The expanded listing given in Annex A contains the complete EXPRESS of
the AIM without annotation. A graphical representation of the AIM is given in annex H. Additional
requirements for specific implementation methods are given in annex C.
This Part of ISO 10303 contains the definition of conforming boundary representation solid models
and the mechanisms to transfer them via an exchange structure as defined in Part ISO 10303-21. The
exchange of such models, with associated visual presentation information is required during the initial
desgn of a mechanical product and when detailed designs of components are communicated to suppliers
and sub-contractors. In this Part B-reps are characterised by the fact that they can represent models with
only planar surfaces (faceted B-rep), models with only analytical surfaces (elementary B-rep) and models
with sculptured surfaces and curves (advanced B-rep). The application reference environment in which
these B-rep models are used is the generation and exchange of volume-based data in the Computer-aided
Mechanical design process. This application places fundamental requirements on the model exchange
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ISO 10303-204:2002(E)
and the neutral representation of models. The transfer and archiving of B-rep models at different stages
of the design and engineering process requires the following to be maintained:
— the completeness of the models when mapped between application systems;
— the correctness of semantics of the representation;
— the accuracy of the geometric relationships between entity instances which form part of a B-rep
model; in particular all vertices shall lie on the edges using them and all edge_curves shall lie on
each face using this edge as part of the boundary.
Three different classes of implementation are specified in clause 6.
This application protocol was developed as one component of a series of Mechanical Design application
protocols and is complemented by ISO 10303-205 Mechanical design using surface models, see (1).
These Parts share a common application environment and have a similar scope for the representation
of mechanical parts. The significant differences among these Parts of ISO 10303 is in the manner in
which the shape of a mechanical part is represented. In this Part the representation is as a manifold solid
boundary representation model. In ISO 10303-205 the shape of the part is represented by a surface model
in which all surfaces and bounding curves are fully represented. Figure 1 gives a pictorial representation
of the scope of this AP.
NOTE 1 In figure 1 the term scope refers to the intended scope of the information models in this Part of ISO
10303. These information models may be useful as part of an information model for applications shown as ’out of
scope’ in this diagram.
Figure 2 contains the data planning model that gives a high level description of the requirements for this
application protocol, as well as the relationships between the basic data objects.
NOTE 2 A dashed line in figure 2 is used to denote an optional association.
The planning model illustrates that a product may be either a part or an assembly. The shape of a part
or assembly is represented by a shape model which takes the form of one, or more, B-reps. Each B-rep
is either a faceted B-rep, an elementary B-rep, or an advanced B-rep. Names can be associated with
products, parts or shape models. Visual properties may optionally be attached to B-rep models.
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ISO 10303-204:2002(E)
CAD Models6

Other Solid Models

CSG Models
’$
B-rep Models
freeform geometry

B-rep Models
Part 204 Scope
analytic geometry

Faceted B-rep
&%
Surface Models

Wireframe Models

2D Drawings
Mechanical Engineering Applications
-
???????
2d Initial Detail Assemblies FE NC Robotics
Design 3D Design Part Design Analysis Programming
Figure 1 – The scope of this part of ISO 10303 in the contexts of CAD
models and mechanical engineering applications
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ISO 10303-204:2002(E)
PRODUCT
ASSEMBLY PART
SHAPE
NAME
MODEL
VISUAL
B-rep
APPEARANCE
elementary
faceted advanced
B-rep B-rep
B-rep
Figure 2 – Data planning model
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ISO 10303-204:2002(E)
INTERNATIONAL STANDARD
Industrial automation systems and integration —
Product data representation and exchange —
Part 204:
Application protocol:
Mechanical design using boundary representation
1Scope
This part of ISO 10303 specifies the use of the integrated resources necessary for the scope and informa-
tion requirements for the use and exchange of boundary representation solid models in the mechanical
engineering design context.
NOTE The application activity model in annex F provides a graphical representation of the processes and infor-
mation flows that are the basis for the definition of the scope of this part of ISO 10303.
This document describes an application reference environment for the generation and exchange of volume-
based design data in the computer-aided mechanical design process, together with appropriate data mod-
els and a physical file implementation form. The information model supports all geometric and topolog-
ical aspects of a complete description of the shape and size of an object. It was originally developed for
applications in mechanical engineering design using the CAD modelling technique boundary represen-
tation (B-rep) solid modelling and may be appropriate for other application areas using this technique.
The following are within the scope of this Part of ISO 10303:
— Three types of B-rep model that are used to represent shape:
a) faceted B-rep model;
b) B-rep model with elementary surfaces;
c) B-rep model with sculptured surfaces;
— curve and surface geometry;
— curves defined in parameter space (pcurves);
— manifold topology;
— product identification information;
— the association of simple presentation attributes such as line-style, line-width, colour with an entire
B-rep model, or, with geometric or topological elements of a B-rep model;
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ISO 10303-204:2002(E)
— preservation of user-defined names of objects;
— units and measures associated with geometric elements;
— assemblies of parts and sub-assemblies.
The following are outside the scope of this Part of ISO 10303:
— Other types of shape representation:
a) wireframe models;
b) surface models;
c) geometrically trimmed curves and surfaces;
d) constructive solid geometry models;
e) compound B-rep models.
— Geometric and topological data:
a) 2D geometry, other than for the definition of pcurves;
b) self-intersecting geometry;
c) non-manifold topology.
— Dimensioning;
— Tolerances;
— Manufacturing information;
— Advanced presentation features such as multiple views, character fonts and symbols.
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ISO 10303-204:2002(E)
2 Normative references
The following normative documents contain provisions which, through reference in this text, constitute
provisions of this part of ISO 10303. For dated references, subsequent amendments to, or revisions of,
any of these publications do not apply. However, parties to agreements based on this part of ISO 10303
are encouraged to investigate the possibility of applying the most recent editions of the normative docu-
ments indicated below. For undated references, the latest edition of the normative document referred to
applies. Members of ISO and IEC maintain registers of currently valid International Standards.
ISO 10303-1:1994, Industrial automation systems and integration — Product data representation and
exchange— Part 1: Overview and fundamental principles
ISO 10303-11:1994, Industrial automation systems and integration — Product data representation and
exchange— Part 11: Description methods: The EXPRESS language reference manual
ISO 10303-21:1994, Industrial automation systems and integration — Product data representation and
exchange— Part 21: Implementation methods: Clear text encoding of the exchange structure
ISO 10303-22:1998, Industrial automation systems and integration — Product data representation and
exchange— Part 22: Implementation methods: Standard data access interface
ISO 10303-31:1994, Industrial automation systems and integration— Product data representation and
exchange— Part 31: Conformance testing methodology and framework: General concepts
ISO 10303-41:1994, Industrial automation systems and integration — Product data representation and
exchange— Part 41: Integrated generic resources: Fundamentals of product description and support
ISO 10303-42:1994, Industrial automation systems and integration — Product data representation and
exchange— Part 42: Integrated generic resources: Geometric and topological representation
ISO 10303-43:1994, Industrial automation systems and integration — Product data representation and
exchange— Part 43: Integrated generic resources: Representation structures
ISO 10303-44:1994, Industrial automation systems and integration — Product data representation and
exchange— Part 44: Integrated generic resources: Product structure configuration
ISO 10303-46:1994, Industrial automation systems and integration — Product data representation and
exchange— Part 46: Integrated generic resources: Visual presentation.
ISO 10303-511:2001, Industrial automation systems and integration— Product data representation
and exchange— Part 511: Application interpreted construct: Topology bounded surface
ISO 10303-512:1999, Industrial automation systems and integration— Product data representation
and exchange— Part 512: Application interpreted construct: Faceted boundary representation
ISO 10303-513:2000, Industrial automation systems and integration— Product data representation
and exchange— Part 513: Application interpreted construct: Elementary boundary representation
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ISO 10303-204:2002(E)
ISO 10303-514:1999, Industrial automation systems and integration— Product data representation
and exchange— Part 514: Application interpreted construct: Advanced boundary representation
ISO 10303-517:2000, Industrial automation systems and integration— Product data representation
and exchange— Part 517: Application interpreted construct: Mechanical design geometric presentation
1)
ISO 10303-518 , Industrial automation systems and integration — Product data representation and
exchange— Part 518: Application interpreted construct: Mechanical design shaded presentation
ISO/IEC 8824-1:1998, Information technology— Abstract Syntax Notation One (ASN.1): Specification
of basic notation
1)
To be published.
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ISO 10303-204:2002(E)
3 Terms, definitions, and abbreviations
3.1 Terms defined in ISO 10303-1
For the purposes of this part of ISO 10303, the following terms defined in ISO 10303-1 apply.
— abstract test suite;
— application;
— application activity model (AAM);
— application context;
— application interpreted model (AIM);
— application object;
— application protocol (AP);
— application reference model (ARM);
— assembly;
— component;
— conformance class;
— conformance requirement;
— conformance testing;
— context;
— data;
— data exchange;
— implementation method;
— interpretation;
— integrated resource;
— model;
— PICS proforma;
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ISO 10303-204:2002(E)
— presentation;
— product;
— product data;
— resource construct;
— structure;
— unit of functionality (UoF);
3.2 Terms defined in ISO 10303-42
For the purposes of this part of ISO 10303, the following terms defined in ISO 10303-42 apply.
— arcwise connected;
— boundary;
— boundary representation solid model;
— bounds;
— curve;
— euler equations;
— inside;
— interior;
— parameter space;
— surface;
— topological sense.
3.3 Terms defined in ISO 10303-44
For the purposes of this part of ISO 10303, the following terms defined in ISO 10303-44 apply.
— bill_of_material structure;
— component;
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ISO 10303-204:2002(E)
— constituent;
— form, fit and function.
3.4 Other definitions
For the purposes of this part of ISO 10303 the following definitions apply:
3.4.1
advanced B-rep
general boundary representation model which may have any geometric form for the faces and edges. In
particular B-splines may be used to define the face and edge geometry.
3.4.2
computer-aided design
way of designing mechanical and other products utilizing computerized tools.
3.4.3
elementary B-rep
boundary representation model in which all surfaces are planar, cylindrical, conical, spherical or toroidal.
3.4.4
elementary geometry
geometry composed of lines, polylines, conics and elementary_surfaces.
3.4.5
faceted B-rep
simplified boundary representation model with planar faces and implicitly defined edges and vertices.
3.4.6
functional level
indicator used to distinguish geometric complexity of a B-rep model or other representation.
3.4.7
genus
topological property used to classify solids. The genus of a solid is an abstraction for the number of
through holes in the solid.
3.4.8
manifold solid
arcwise connected solid such that, the interior of any infinitessimally small sphere, centred at any point
on the boundary of the solid, is divided into precisely 2 regions, inside and outside the solid respectively.
3.4.9
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ISO 10303-204:2002(E)
normal direction
unit vector perpendicular to a surface and pointing away from the material.
3.4.10
orientation
mathematical sense of curves, loops or edges.
3.4.11
product version
identifier for a variant of a product.
3.5 Abbreviations
For the purposes of this Part of ISO 10303, the following abbreviations apply:
B-rep Boundary representation solid
CAE Computer Aided Engineering
CIM Computer Integrated Manufacturing
CSG Constructive Solid Geometry
FEA Finite Element Analysis
ID Identification
IDEF0 ICAM definition language 0
NIAM Nijssen’s Information Analysis Method
NC Numerical Control
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ISO 10303-204:2002(E)
4 Information requirements
This clause specifies the information required for mechanical design using boundary representation.
The information requirements are specified as a set of units of functionality, application objects, and
application assertions. These assertions pertain to individual application objects and to relationships
between application objects. The information requirements are defined using the terminology of the
subject area of this application protocol.
NOTE 1 A graphical representation of the information requirements is given in annex G.
NOTE 2 The information requirements correspond to those of the activities identified as being within the scope
of this application protocol in annex F.
NOTE 3 The mapping table specified in 5.1 shows how the integrated resources and application interpreted
constructs are used to meet the information requirements of this application protocol.
These requirements apply to system developers developing conforming implementations and to users of
this application protocol to exchange physical files containing B-rep model data. An implementation
claiming to conform to this application protocol shall ensure that the structure and constraints defined by
these information requirements are satisfied when physical files are exchanged.
Functional Levels
The information requirements for mechanical design using boundary representation models are presented
in terms of three distinct levels of functionality. The
...