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

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 the

computer-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 " ST andard for

the E xchange of P roduct model data".

Data Exchange Standards and STEP http://www.iso.org/

Data Exchange Standards and STEP 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

T he series of 400 and 1000 are introduced.

STEP Architecture

Environment

o Parts 1x: Description methods: EXPRESS, EXPRESS-X

o Parts 2x: Implementation methods: STEP-File, STEP-XML, SDAI

o Parts 3x: Conformance testing methodology and framework

Integrated data models

o 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 parts

o Parts 2xx: Application Protocols (AP)

o Parts 3xx: Abstract Test Suites (ATS) for APs

o Parts 4xx: Implementation modules for APs

STEP Architecture

Application Protocols (AP)

T op parts of STEP

Conformance Classes (cc) are suitable for a particular kind of product or data exchange scenario.

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

D evelopment 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)

T he mediator between the AAM and the AIM/MIM.

I ts 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 Protocols and Abstract Test Suites Parts 2 XX & 3 XX Generic Resources Parts 41-99 A IC / Implementation modules Parts 4XX, 5 XX Integrated Resources Application Resources Parts 101+ Implementation Methods Part 21 Exchange File, Parts 22-29 Description Methods Part 11 EXPRESS Framework Part 13 STEP Development Methodology Conformance Methods Part 31 Conformance Testing Methods: General Concepts Parts 32-39 Application Modules Parts 1 XXX

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 with Design, Architecture, Engineering and Construction issues. * They already IS.

STEP Architecture

Coverage of STEP Application Protocols (AP)

Design APs

Mechanical

Building

Part 202 - Associative draughting. 2D/3D drawing with association,

but no product structure.

Part 225 - Building elements using explicit shape representation

Connectivity oriented electric, electronic and piping/ventilation

Ship

Others

Manufacturing APs

Life 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 and

associated 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

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.

* I nformation 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 type s .

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.

EXPRESS mammal human cat dog 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 student business owner employee 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 SELFclosed_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.

E verything 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 Simple types symbols Type definition symbols BOOLEAN LOGICAL BINARY NUMBER INTEGER REAL STRING anEnumeration aSelect userDefinedType

EXPRESS-G Entity symbol Relationship line styles attribute Optional attribute subtype-supertype

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 EXPRES S SCHEMA 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

ISO 10303-21 File Example ISO-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; Primitive attributes Complex attributes x y line point REAL end1 end2

Example 2 – cont. Instance Model Fragment Part 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