Data Exchange Standards & STEP, EXPRESS & EXPRESS-G

Data Exchange Standards & STEP, EXPRESS & EXPRESS-G

Alper DİNÇER

02 December 2008

Contents

Data Exchange Standards and STEP STEP Architecture EXPRESS EXPRESS-G Example of EXPRESS and EXPRESS-G Results

Data Exchange Standards and STEP

Technology is advancing rapidly Different user needs Different kinds of software Different data formats


Need to work interoperable Conversion is not fully compatible

Need for a standard!


ISO started Technical Committee (TC) 184

Subcommittee (SC) 4 TC184/SC4 -> Industrial data


ISO 10303 is an ISO standard for thecomputer-interpretable representation and exchange of industrial product data. Its official title is "Industrial automation systems and integration - Product data representation and exchange", known as "STEP" or "STandard for the Exchange of Product model data".


http://www.iso.org/


http://www.tc184-sc4.org/


STEP has three phases : Phase 1 (1994/95) Phase 2 (2002) Phase 3 (Still going on)

It is the successor of IGES and VDA-FS


Phase 1: parts 1, 11, 21, 31, 41, 42, 43, 44, 46,

101, AP201 and AP203 are released


Phase 2: AP202, 209, AP210, AP212, AP214,

AP224, AP225, AP227 and AP232 are released.


Phase 3: Standard is getting bigger and bigger Overlapping occurs Harmonization needed.

Modular Architecture is developed The series of 400 and 1000 are introduced.

STEP Architecture

Environmento Parts 1x: Description methods: EXPRESS, EXPRESS-Xo Parts 2x: Implementation methods: STEP-File, STEP-XML, SDAIo Parts 3x: Conformance testing methodology and framework

Integrated data modelso The Integrated Resources (IR), consisting of

+ Parts 4x and 5x: Integrated generic resources+ Parts 1xx: Integrated application resources+ PLIB ISO 13584-20 Parts library: Logical model of expressions

o Parts 5xx: Application Integrated Constructs (AIC)o Parts 1xxx: Application Modules (AM)

Top partso Parts 2xx: Application Protocols (AP)o Parts 3xx: Abstract Test Suites (ATS) for APso Parts 4xx: Implementation modules for APs

STEP Architecture

Application Protocols (AP) Top parts of STEP Conformance Classes (cc) are suitable for a

particular kind of product or data exchange scenario.

Information requirements and usage scenarios an informative application activity model (AAM) is added to every AP, using IDEF0. ,

Development of an ATS was very expensive

STEP Architecture

Application Integrated Model (AIM) / Module Integrated

Models (MIM). They are constructed by choosing generic objects defined in

lower level data models (4x, 5x, 1xx, 5xx) The models are the basis for interoperability between APs for

different kinds of industries and life cycle stages

STEP Architecture

The Application Reference Models (ARM) The mediator between the AAM and the AIM/MIM. Its purpose was only to document high level application

objects and the basic relations between them EXPRESS which was originally only developed for the AIM

was also used for the ARM.

STEP Architecture

ATS

ATS = Abstract Test Suite

STEP Architecture

Application Protocolsand Abstract Test Suites

Parts 2XX & 3XX

Generic Resources Parts 41-99

AIC / Implementation modules Parts 4XX, 5XX

Integrated Resources

Application Resources Parts 101+

Implementation MethodsPart 21 Exchange File, Parts 22-29

Description Methods

Part 11 EXPRESS

Framework

Part 13 STEP Development Methodology

ConformanceMethods

Part 31 Conformance Testing Methods: General Concepts

Parts 32-39

Application ModulesParts 1XXX

STEP Architecture

Part 439 - AP239 product life cycle support

* Part 1287 - AP239 activity recording * Part 1297 - AP239 document management * Part 1289 - AP239 management resource information * Part 1293 - AP239 part definition information * Part 1292 - AP239 product definition information * Part 1304 - AP239 product status recording * Part 1295 - AP239 properties * Part 1306 - AP239 task specification resourced * Part 1307 - AP239 work definition

Application Protocols (AP)

Implementation modules

Application Modules

STEP Architecture

STEP Architecture

* AP202 and AP225 are related withDesign, Architecture, Engineering and Construction issues. * They already IS.

STEP Architecture

Coverage of STEP Application Protocols (AP)Design APs Mechanical Building

o Part 202 - Associative draughting. 2D/3D drawing with association, but no product structure.

o Part 225 - Building elements using explicit shape representation Connectivity oriented electric, electronic and piping/ventilation Ship Others

Manufacturing APsLife Cycle Support APs

STEP Architecture

AP 202 - Associative Draughting (ISO 10303-202:1996) This part of ISO 10303 provides for the inter-organization exchange of computer-interpretable drawing information andassociated product definition data. 10 Conformance Classes : cc 1: Administration, annotation, data organization (layers, groups), and drawing

structure presentation (colors, fonts) without shape cc 2: cc 1 and elementary 2D geometrically bounded wireframe cc 3: cc 1 and all 2D geometrically bounded wireframe cc 4: cc 1 and 2D topological wireframe cc 5: cc 1 and 3D geometrically bounded wireframe and/or surfaces cc 6: cc 1 and 3D topological wireframe cc 7: cc 1 and faceted B-Rep cc 8: cc 1 and elementary B-Rep cc 9: cc 1 and advanced B-Rep cc 10: cc 1 and manifold surface models with topology

STEP Architecture

STEP Architecture

AP225 - Building Elements Using Explicit Shape Representation (ISO 10303-225:1999)

* This part of ISO 10303 specifies the building element shape, property, and spatial arrangement information requirements for building elements. * Information requirements specified in this part support the following activities: Concurrent design processes or building design iterations; Integration of building structure designs with building systems designs to enable design analysis; Building design visualization; Specifications for construction and maintenance; and Analysis and review. (e.g., A design analysis function combines the building structure design with

building service systems designs (for systems such as heating, ventilation, and air conditioning (HVAC) and piping) to check for physical clashes of the building structural elements with piping or air conditioning elements.

* AP225 has 14 Conformance Classes can be accessible from the report

STEP Architecture

EXPRESS

EXPRESS is a standard data modeling language for product data. EXPRESS is formalized in the ISO Standard for the Exchange of Product model STEP (ISO 10303), and standardized as ISO 10303-11.

Main Elements: Schema Type Entity Rule

Other Elements Constants Functions and procedures Executable statements

EXPRESS

Schema is the main container for all EXPRESS elements.

SCHEMA YourSchemaName;

[type declarations][entity declarations][rule declarations][functions]

END_SCHEMA;

EXPRESS

Types are the smallest elements of EXPRESS. They are using in entities to define their properties or attributes.

Type hierarchy can be seen as follows:

Simple (built-in) types: BINARY, BOOLEAN, INTEGER, LOGICAL, NUMBER, REAL, STRING

Collection types: Array (fixed size, ordered) Bag (variable size, no order, dublication allowed) Set (like bag but without duplicates, no order) List (variable size, no dublication, ordered)

Enumeration type Select type (supertype-subtype) User Defined Types

TYPE trafficLightColor = ENUMERATION OF (Red, Amber, Green);END_TYPE;

EXPRESS

Entity is a reflection of real world objects. It is composed of types.

Entities can be used as an attribute of other entities. The difference between type and entity is that

entities can have instances, but types can not. They can also have to parameters as “OPTIONAL”

and “DERIVE”.

EXPRESS

ENTITY point; x : REAL; y : REAL;END_ENTITY;

ENTITY line; end1 : point; end2 : point; length : distance;END_ENTITY;

ENTITY polyline; lines : LIST[ 1 : ? ] OF line;END_ENTITY;

EXPRESS

ENTITY line; start : point; end : point;DERIVE length : distance:=SQRT((end.xcoord - start.xcoord)**2 + (end.ycoord - start.ycoord)**2);END_ENTITY;

ENTITY person; first_name : STRING; last_name : STRING; nickname : OPTIONAL STRING;END_ENTITY;

EXPRESS

Inverse Relationships A complete relation between classes may

need to be described in both the normal direction as described above and in the inverse direction. An inverse relationship is indicated by writing (INV) at the front of the name of the relationship.

EXPRESS

ENTITY employee; name : person_name;END_ENTITY;

ENTITY person_name; last_name : STRING; first_name : STRING;INVERSE link : employee FOR name;END_ENTITY

EXPRESS

Supertype/ Subtype Relationships There is a general specification for a class but that

this is expanded by particular characteristics of subtypes. Each subtype has all the characteristics of the layered element acquired by INHERITANCE. However, each subtype may have additional attributes.

The term (ABS) is used to indicate that it is an abstract supertype. This means that it cannot exist in itself, only by virtue of its subtypes.

EXPRESSmammal

human catdog

1

ENTITY mammal ABSTRACT SUPERTYPE OF (OneOf(human,dog,cat)); weight : REAL;END_ENTITY;

ENTITY human SUBTYPE OF (mammal);(* human attributes *)END_ENTITY;

ENTITY dog SUBTYPE OF (mammal);(* dog attributes *)END_ENTITY;

ENTITY cat SUBTYPE OF (mammal);(* cat attributes *)END_ENTITY;

OneOf Property

EXPRESS

person

studentbusiness

owneremployee

ENTITY person ssn : STRING;END_ENTITY;

ENTITY student SUBTYPE OF (person);(*student attributes*)END_ENTITY;

ENTITY employee SUBTYPE OF (person);(*employee attributes*)END_ENTITY;

ENTITY business_owner SUBTYPE OF (person);(*business_owner atts*)END_ENTITY;

Subtypes/Supertypes (AndOr)

EXPRESS

Local Rules vs Global Rules Local rules are defined within the

entities and they are valid only for entity defined in

Global rules are defined within the schema and valid for whole model.

EXPRESS

ENTITY unit_vector; a,b,c : REAL;WHERE unit_length_rule : a**2+b**2+c**2 = 1.0;END_ENTITY;

ENTITY student; first_name : STRING; last_name : STRING; ssn : STRING;UNIQUE unique_ssn_rule : ssn;END_ENTITY;

Local Rules

EXPRESS

RULE max_number_of_students FOR (student); WHERE max_is_40 : SIZEOF(student) <= 40;END_RULE;

RULE rule_name FOR (entity_type_1,…, entity_type_N); (* executable statements *)WHERE (* some expression that returns TRUE or FALSE *)END_RULE;

Global Rules

EXPRESS

Functions are the methods defined within the schema. They are object's abilities. Functions are used to do something in schema related with entities.

EXPRESS

FUNCTION days_between( d1 : date, d2 : date ) : INTEGER; (* returns the number of days between the two input dates. If d1 is earlier than d2, a positive number is returned *)END_FUNCTION;

ENTITY destroyed_part; production_date : date; destruction_date : date;WHERE dates_ok : days_between(production_date,destruction_date) >=0;END_ENTITY;

EXPRESS

ENTITY closed_planar_curve ABSTRACT SUPERTYPE; area : REAL;END_ENTITY;

ENTITY circle SUBTYPE OF (closed_planar_curve); center : point; radius : REAL;DERIVE SELF\closed_planar_curve.area : REAL := PI*radius**2;END_ENTITY;

Attribute Redeclaration

EXPRESS-G

EXPRESS-G is a standard graphical notation for information models. It is a useful companion to the EXPRESS language for displaying entity and type definitions, relationships and cardinality.

Everything that is drawn in EXPRESS-G can be defined in EXPRESS. However, not everything that can be defined in EXPRESS can be drawn in EXPRESS-G.

EXPRESS-G

BOOLEAN LOGICAL BINARY

NUMBER INTEGER REAL STRING

Simple types symbols

anEnumeration aSelectuserDefinedType

Type definition symbols

EXPRESS-G

Entity symbol

attribute Optional attribute subtype-supertype

Relationship line styles

EXPRESS-G

Cross references Graphical representations can span more

than one page. If a relationship occurs between definitions on separate pages, the relationship line on each of the two pages is ended by a rounded box. It contains the page number, the reference number and the name of the entity referred to.

Example of EXPRESSSCHEMA example; TYPE hair_type = ENUMERATION OF (blonde, black, brown, white); END_TYPE; TYPE date = ARRAY [1:3] of integer; END TYPE; ENTITY person SUPERTYPE OF (ONEOF(female, male)); first_name : STRING; last_name : STRING; nickname : OPTIONAL STRING; birth_date : date; children : SET [0:?] OF person; hair : hair_type; DERIVE age : INTEGER := years(birth_date); INVERSE parents : SET [0:2] OF person FOR children; END_ENTITY;

ENTITY female SUBTYPE OF (person); INVERSE husband : SET [0:1] OF male FOR wife; ---husband is optional! END_ENTITY; ENTITY male SUBTYPE OF (person); wife : OPTIONAL female; END_ENTITY;

FUNCTION years(past : date): INTEGER; (*This function calculates years from birthdate and current date.) END_FUNCTION;END_SCHEMA;

Example of EXPRESS-G

person

male female

INTEGER

STRING

2,5 date

hair_typehairchildren S[0:?]

(INV) parents S[0:2]

birth_date

first_name

last_name

nickname

(DER) age

1

wife

(INV) husband

2,5 (1) INTEGERdateA[1:3]

Page 1 of 2

Page 2 of 2expg

ISO 10303-21 File ExampleISO-10303-21;HEADER;FILE_DESCRIPTION((‘This is a sample person schema’),’1’);FILE_NAME(‘Example P21 File’,’1999-08-08 T15:30:00’,(‘J.Doe’), (PDES, Inc.’),‘Version 1’,’APPROVED BY P.H. Boss’);FILE_SCHEMA;ENDSEC;DATA;#1=PERSON(‘Dilbert’,’Jones’,$,(30,5,1962),(),.WHITE.);#2=PERSON(‘Wally’,’Smith’,$,(30,5,1960),(#11,#20),.BROWN.);...#10=MALE(‘Pointy’,’Boss’,$,(29,05,1961),(),.BLACK.,#21);#11=MALE(‘Atos’,’Smith’,$,(16,03,1990),(),.BROWN.,$);...#20=FEMALE(‘Ellen’,’Smith’,$,(08,03,1992),().BLONDE.);#21=FEMALE(‘Francis’,’Boss’,’Fran’,(18,6,1962),(),.BROWN.);. .ENDSEC;END-ISO-10303-21;

MetaData

Data

Example 2

SCHEMA example1;

ENTITY point; x : REAL; y : REAL;END_ENTITY;

ENTITY line; end1 : point; end2 : point;END_ENTITY;

END_SCHEMA;

x

y

line

point

REAL

end1

end2

Primitive attributes

Complex attributes

Example 2 – cont.

21 3 4 5 6 7

2

1

3

4

5

6

x

y

21 3 4 5 6 7

2

1

3

4

5

6

x

y

P01 L01 P02

L03

P03

Instance Model FragmentPart 21 (p21) format

#10 = POINT (2.0, 2.0);#20 = POINT (5.0, 2.0);#30 = POINT (5.0, 4.0);#110 = LINE (#10, #20);#150 = LINE (#10, #30);

Reference to another instance

Instance identifier (arbitrary number within a given p21 model) Attribute values (in order

as given in schema)

Results

Why EXPRESS? Precision in definition of information model Allows use of computers to check for

consistency of presentation Allows use of computers to develop any number

of secondary views, particularly implementation views

Results

STEP is designed to provide specifications and methods that enable the exchange and sharing of enterprise information

New approaches are defining a modular architecture and methods for using STEP on the Web

STEP provides a flexible way for implementors to meet the data exchange needs for multiple industries and disciplines

Thanks for attention!