Modeling Requirements, Architectures, Behaviour...

Transcription

1 Modeling Requirements, Architectures, Behaviour... The System Modeling Language (SysML) and the SYSMOD modeling approach Budapest University of Technology and Economics Department of Measurement and Information Systems

2 Acknowledgement Portions of this presentation are from o Systems Engineering with SysML/UML, by Tim Weilkiens, published by Morgan Kaufmann Publishers, Copyright 2007 Elsevier Inc. All rights reserved. o A Practical Guide to SysML, by Sanford Friedenthal, Alan Moore, and Rick Steiner, published by Morgan Kaufmann Publishers, Copyright 2009 Elsevier Inc. All rights reserved. o IBM course, Requirements management 2

3 Overview Context SysML Overview SysML details + the SYSMOD Systems Engineering Methodology 3

4 Systems Engineering Systems Engineering is a multidisciplinary approach to develop balanced system solutions in response to diverse stakeholder needs ~ Integration Engineering o Software engineering o Hardware engineering o Mechanical engineering o Safety engineering o Security engineering o... ~ Process Engineering System o Military, airplane, car, aviation, railway interlocking, notebook, etc. 4

5 Systems Engineering Process V-model 5

6 V-model v2 EN

7 V-model v3 7 Vision Operational Use Stakeholder Requirements Problem Space Acceptance Tests Solution Space System Requirements Component Requirements Component Tests System Tests

8 Differentiating Problem and Solution 8 Problem Solution Stakeholder requirements A description of the problem and its context Describes what stakeholders want from the system Not the definition of the solution (except for environment) Quality of results Created by stakeholders System requirements An abstract representation of the solution Describes what the system will do Not the definition of the design How well it does it Created by systems engineers The user shall be able to... The system shall do.

9 9 Input Specification agree with customer Acceptance Strategy Request Change analyze & model Request Change Models derive requirements and acceptance strategy Request Change Output Specification agree with supplier Acceptance Strategy

10 10 Vision Operational Use Stakeholder Requirements Acceptance Tests System Requirements System Tests Component Requirements Component Tests

11 Models Bridge Layers of Requirements 11 Vision e.g Goal / Usage modeling Stakeholder Requirements Functional e.g. Functional modeling modeling System Requirements Functional Functional e.g. Performance modeling modeling modeling Subsystem Requirements

12 Vision Importance of Traceability Impact Analysis Operational Use satisfies Accepting the product Stakeholder Requirements Acceptance Strategy satisfies Validating the product System Requirements System Test satisfies Verifying the product Architecture Acceptance Strategy Evaluating subsystems 12

13 Vision Importance of Traceability Coverage analysis Operational Use satisfies Stakeholder Requirements Acceptance Strategy satisfies? System Requirements System Test satisfies? Architecture Acceptance Strategy 13

14 Overview Context SysML Overview SysML details + the SYSMOD Systems Engineering Methodology 14

15 SysML overview UML for Systems Engineering o Supports the specification, analysis, design, verification and validation of systems that include hardware, software, data, personnel, procedures, and facilities Developed by OMG and International Council on Systems Engineering (INCOSE) OMG SysML ( o RFP March 2003 o Version 1.0 September 2007 o Version 1.1 November 2008 o Version 1.2 June 2010 o Version 1.3 June

16 Relationship Between SysML and UML UML 2 UML4SysML SysML UML not required by SysML (UML - UML4SysML) UML reused by SysML UML 2 Reuse (1, 2) SysML extensions to UML SysML Profile 16

17 SysML Diagram Taxonomy 17

18 Aspects of SysML 18

19 Overview Context SysML Overview SysML details + the SYSMOD Systems Engineering Methodology 19

20 Language vs. Methodology Modeling Language o Defines elements and their relationship o Defines syntax and semantics o What type of elements can be used during modeling? o E.g. SysML Development Methodology o Defines the steps of analyzing and designing the system o Defines the usage of the model elements and diagrams o How shall the model be built? o E.g. SYSMOD (SYStem MODeling) by Tim Weilkiens 20

21 The SYSMOD approach Analyzing Requirements 21

22 The SYSMOD approach for design 22

23 SysML Activity diagram Name of activity Action in activity Pin Object Parameter of activity Object flow Represents behavior in terms of the ordering of actions based on the availability of inputs, outputs, and control, and how the actions transform the inputs to outputs 23

24 Describe Project Context Car rental system o Works without staff Customer identification needed o Central computer in radio compartment Communicates with central reservation system Collects usage data Comfort features Navigation Radio Phone... 24

25 Determine requirements 25

26 Identify stakeholders 26

27 Identify stakeholders 27

28 Collect requirements 28

29 SysML Requirements diagram Name of diagram Type of context element Name of context element Requirement composition Requirement Requirements diagram Represents text-based requirements and their relationship with other requirements, design elements, and test cases to support requirements traceability 29

30 Collect requirements 30

31 Model System Context 31

32 Identify System Actors 32

33 SysML Block definition diagram Block Actor Block Definition Diagram Represents structural elements called blocks, and their composition and classification 33

34 Model System-Actor Information Flow 34

35 Identify System Interaction Points 35

36 System Context 36

37 Model Use Cases 38

38 Model Use Cases 39

39 SysML Use case diagram Object flow Actor Use case Use Case Diagram Represents functionality in terms of how a system or other entity is used by external entities (i.e., actors) to accomplish a set of goals 40

40 Model Use Cases Organizing use cases into packages 41

41 SysML Requirements traceability 42

42 Describe Use Cases Essences 43

43 Describe Use Cases Essences 44

44 Describe Use Cases Essences 45

45 Model Use Case Flows 46

46 Model Object Flows 47

47 Model Domain Knowledge 48

48 Create Glossary Supports better understanding 49

49 The SYSMOD approach for design 50

50 Model System/Actor Interaction 51

51 SysML Sequence diagram Sequence Diagram Represents behavior in terms of a sequence of messages exchanged between parts 52

52 Derive System Interfaces 53

53 Model System Structures Identify system components 54

54 Model System Structures Identify relation of components 55

55 SysML Internal block diagram Standard port Flow port Item flow Interfaces Part: usage of block type Internal Block Diagram Represents interconnection and interfaces between the parts of a block 56

56 Model System Structures Structural allocation 57

57 Model System Structures Functional allocation: Actions to System components 58

58 Model System Structures Traceability to requirements: Blocks satisfying a req. 59

59 Derive State Model 60

60 Derive State Model 61

61 SysML State Machine Diagram Represents behavior of an entity in terms of its transitions between states triggered by events 62

62 Parametrics Constraints on block properties 66

63 SysML Parametric diagram Parametric Diagram Represents constraints on property values used to support engineering analysis Constraint property node Block value Value binding 67

64 Variant Management 68