1. XASTRO-2 Presentation CCSDS SAWG 17-18 th November 2004

2. XASTRO-2 Presentation2 Presentation Outline Objectives Modelling Approach RASDS Viewpoint Languages Space System Model Metamodel Current Status

3. XASTRO-2 Presentation3 Objectives Improve Interoperability between Ground System Software Reference Architecture Standardised Services Standardised Information Models Standardised Component Configurations / Templates Support Ground Systems Architecture Specification Promote Automation in Ground System Operations Ground System Configuration Documentation Production

4. XASTRO-2 Presentation4 Modelling Approach Basic approach is based on OMG‘s Model Driven Architecture XASTRO-2 Modelling is based on UML 1.4 CCSDS RASDS viewpoint concepts captured using XASTRO-2 Framework UML Profile Borrowing SysML Requirements Model Profile UML 2.0 / SysML is long term objective Much better support for component based modelling Currently lacks stable XMI 2.0 spec and tool support PIM – PSM Mappings XML Schema – information viewpoint CORBA IDL – functional viewpoint

5. XASTRO-2 Presentation5 Architectural Modelling

6. XASTRO-2 Presentation6 Architectural Model Types

7. XASTRO-2 Presentation7 UML Profiles UML Profile extends metaclasses from existing UML metamodel to incorperate new concepts through Stereotypes Tagged Values (name-value pairs) Constraints (OCL) UML Profile can be used to extend UML metamodel (lightweight extension) Incorporate CCSDS RASDS concepts UML Profile can be used for specifying mapping rules from a UML model to an implementation technology XML Schema CORBA IDL

8. XASTRO-2 Presentation8 Communications ViewpointPhysical Viewpoint RASDS Viewpoints Enterprise Viewpoint Information Viewpoint Functional Viewpoint Standardised Data Models Standardised Services XASTRO-2 Framework

9. XASTRO-2 Presentation9 Information Viewpoint Language to model Information Objects and their semantics, independent of technology or distribution concerns Models information in the real system, but not how information is exchanged (this is captured in functional viewpoint) Used to specify standard information domain languages or vocabularies, such as: Monitoring & Control Flight Dynamics Mission Planning

10. XASTRO-2 Presentation10 Information Viewpoint Concepts Information Viewpoint Language supports Complex Type Definitions Inheritance Aggregration Choice Referencing Constraints (OCL) State Machines can be used to show valid state transitions Mapping to XML Schema is supported

11. XASTRO-2 Presentation11 Profile Example – XML Schema Mapping

12. XASTRO-2 Presentation12 Information Viewpoint Example - XTCE

13. XASTRO-2 Presentation13 Auto-generated XTCE XML Schema

14. XASTRO-2 Presentation14 Functional Viewpoint Language to model Functional Objects (independent of technology and distribution concerns) Used to specify standard ground system services / functions End-to-End Services Interactions between functional objects through Interfaces Services realised by interfaces RM-ODP Interface types supported (next slide) Hierarchical decomposition of components not perfect in UML 1.4 – better in UML 2.0 & SysML Can make use of UML behavioral models Activity Diagram (sequencing of interactions on function object interfaces) State Diagram (valid state changes of function object)

15. XASTRO-2 Presentation15 Functional Viewpoint Interfaces Interface types based on RM-ODP Stream Interface Flow of information Audio/Video data, Packet Streams Operation Interface All interactions are operations Interrogation – two way interaction Announcement – one way interaction Signal/Event Interface One way interaction Message / Event Based Systems

16. XASTRO-2 Presentation16 Functional Viewpoint Profile

17. XASTRO-2 Presentation17 Functional Object Example

18. XASTRO-2 Presentation18 Functional Object Example - Analysis

19. XASTRO-2 Presentation19 Functional Object Clients

20. XASTRO-2 Presentation20 Functional Object Composition

21. XASTRO-2 Presentation21 CORBA Generation UML Example: CORBA Mapping : typedef Int16 ValidIndexRange;

22. XASTRO-2 Presentation22 Enterprise Viewpoint Provides Requirements Model UML Profile for modelling of textual requirements and their traceability to system design Based on SysML (v0.85) requirements model Requirements can be assigned to model elements in other viewpoints to determine requirements coverage Modelling of the Organisational or Business Logic aspects of the system can be done using UML modelling concepts (such as Use Cases) Import of requirements from an XML document in UML as XMI to be supported Requirements XML Schema modelled as Information Model

23. XASTRO-2 Presentation23 Requirments Model

24. XASTRO-2 Presentation24 Req‘s Model Example (from SysML)

25. XASTRO-2 Presentation25 Comminications Viewpoint Language to model Communication Objects in a space data system Communications Viewpoint is a subset of the RM-ODP Engineering Viewpoint Functional Objects appear as Basic Engineering Objects in the Communication Viewpoints Communication between Engineering Objects is via Channels Basic Engineering Objects can be mapped to Functional Objects by a stereotyped association Engineering (and Technology) Viewpoint metamodel and UML 1.4 profile has already developed by David Frankel We plan to reuse the profile from David Frankel, with some possible modifications

26. XASTRO-2 Presentation26 Engineering Viewpoint Objects

27. XASTRO-2 Presentation27 Engineering Viewpoint Channels

28. XASTRO-2 Presentation28 Commincations Views Example

29. XASTRO-2 Presentation29 Physical Viewpoint Language to model Physical Objects in a space data system Profile is TBD, but is likely to be very simple (stereotype UML component as a physical component) Nodes in the communication viewpoint could be allocated to physical components (stereotyped association)

30. XASTRO-2 Presentation30 Space System Model

31. XASTRO-2 Presentation31 Space System Model Knowledge

32. XASTRO-2 Presentation32 Current Status XASTRO-2 profile undergoing development and will continue in response to feedback from modellers Modelling of the Reference Architecture starting Split between XASTRO-2a and XASTRO-2b teams Using Magic Draw 8.0 (excellent XMI support) Tools to be developed have been identified Requirements Import Tool CORBA IDL Generation Tool XML Schema Generation Tool Documentation Generation Tool XASTRO-2 (Space System Model) Editor Web Portal – http://portal.vega.de/xastrohttp://portal.vega.de/xastro Contact Niklas Lindman (niklas.lindman@esa.int) to request full accessniklas.lindman@esa.int