book

A Practical Guide to SysML: The Systems Modeling Language

Name: A Practical Guide to SysML: The Systems Modeling Language
ISBN: 9780123743794

by Sanford Friedenthal, Alan Moore, Rick Steiner

July 2008

Intermediate to advanced

576 pages

15h 28m

English

Morgan Kaufmann

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Copyright
Morgan Kaufmann OMG Press
Preface
Acknowledgments
About the Authors
I. Introduction
1. Systems Engineering Overview
1.1. Motivation for Systems Engineering1.2. The Systems Engineering Process1.3. Typical Application of the Systems Engineering Process1.4. Multidisciplinary Systems Engineering Team1.5. Codifying Systems Engineering Practice through Standards1.6. Summary1.7. Questions
2. Model-Based Systems Engineering
2.1. Contrasting the Document-Based and Model-Based Approach2.1.1. Document-Based Systems Engineering Approach2.1.2. Model-Based Systems Engineering ApproachThe System ModelThe Model RepositoryTransitioning to MBSE2.2. Modeling Principles2.2.1. Model and MBSE Method Definition2.2.2. The Purpose for Modeling a System2.2.3. Establishing Criteria to Meet the Model PurposeIs the model’s scope sufficient to meet its purpose?Is the model complete relative to its scope?Is the model well formed such that model constraints are adhered to?Is the model consistent?Is the model understandable?Are modeling conventions documented and used consistently?Is the model self-documenting in terms of providing sufficient supporting information?Does the model integrate with other models?2.2.4. Model-Based MetricsWhat is the quality of the design?What is the progress of the design and development effort?What is the estimated effort to complete design and development?2.2.5. Other Model-Based Metrics2.3. Summary2.4. Questions
3. SysML Language Overview
3.1. SysML Purpose and Key Features3.2. SysML Diagram Overview3.3. Using SysML in Support of MBSE3.4. A Simple Example Using SysML for an Automobile Design3.4.1. Example Background and Scope3.4.2. Problem Summary3.4.3. Capturing the Automobile Specification in a Requirement Diagram3.4.4. Defining the Vehicle and Its External Environment Using a Block Definition Diagram3.4.5. Use Case Diagram for Operate Vehicle3.4.6. Representing Drive Vehicle Behavior with a Sequence Diagram3.4.7. Referenced Sequence Diagram to Start Vehicle3.4.8. Control Power Activity Diagram3.4.9. State Machine Diagram for Drive Vehicle States3.4.10. Vehicle Context Using an Internal Block Diagram3.4.11. Vehicle Hierarchy Represented on a Block Definition Diagram3.4.12. Activity Diagram for Provide Power3.4.13. Internal Block Diagram for the Power Subsystem3.4.14. Defining the Equations to Analyze Vehicle Performance3.4.15. Analyzing Vehicle Acceleration Using the Parametric Diagram3.4.16. Analysis Results from Analyzing Vehicle Acceleration3.4.17. Using the Vehicle Controller to Optimize Engine Performance3.4.18. Specifying the Vehicle and Its Components3.4.19. Requirements Traceability3.4.20. Package Diagram for Organizing the Model3.4.21. Model Interchange3.5. Summary3.6. Questions
II. Language Description
4. SysML Language Architecture
4.1. The OMG SysML Language Specification4.2. The Architecture of the SysML Language4.2.1. The General-Purpose Systems Modeling Domain4.2.2. The Modeling Language (or Metamodel)4.2.3. The System Model (or User Model)4.2.4. Model Interchange4.3. SysML Diagrams4.3.1. Diagram Frames4.3.2. Diagram HeaderDiagram KindModel Element TypeDiagram NameDiagram Usage4.3.3. Diagram Description4.3.4. Diagram ContentProperties and KeywordsNode SymbolsPath SymbolsIcon SymbolsNote Symbols4.3.5. Additional Notations4.4. The Surveillance System Case Study4.4.1. Case Study Overview4.4.2. Modeling Conventions4.5. Chapter Organization for Part II4.6. QuestionsDiscussion Topics

5. Organizing the Model with Packages
5.1. Overview5.2. The Package Diagram5.3. Defining Packages Using a Package Diagram5.4. Organizing a Package Hierarchy5.5. Showing Packageable Elements on a Package Diagram5.6. Packages as Namespaces5.7. Importing Model Elements into Packages5.8. Showing Dependencies between Packageable Elements5.9. Specifying Views and Viewpoints5.10. Summary5.11. QuestionsDiscussion Topic
6. Modeling Structure with Blocks
6.1. Overview6.1.1. Block Definition Diagrams6.1.2. Internal Block Diagram6.2. Modeling Blocks on a Block Definition Diagram6.3. Modeling the Structure and Characteristics of Blocks Using Properties6.3.1. Modeling Block Composition Hierarchies Using Part PropertiesComposite AssociationsModeling Parts on an Internal Block DiagramConnecting Parts on an Internal Block DiagramModeling Deeply Nested Structures and Connectors6.3.2. Modeling Noncomposite Relationships between Blocks Using Reference PropertiesReference AssociationsModeling Reference Properties on Internal Block DiagramsUsing Associations to Define Common Features of ConnectorsAssociation Blocks6.3.3. Modeling Quantifiable Characteristics of Blocks Using Value PropertiesModeling Value Types on a Block Definition DiagramAdding Units and Dimensions to Value TypesThe SI Standard for Units and DimensionsAdding Value Properties to BlocksDerived PropertiesModeling Property Values and Distributions6.4. Modeling Interfaces Using Ports and Flows6.4.1. Modeling Items that Flow6.4.2. Modeling Flows between Internal Block Diagram Parts6.4.3. Modeling Flow-Based Interfaces Using Flow PortsAtomic Flow PortsNonatomic Flow PortsConnecting Flow Ports on an Internal Block DiagramDelegating Responsibility between PortsModeling Flows between Ports6.5. Modeling Block Behavior6.5.1. Modeling the Main Behavior of a Block6.5.2. Specifying the Behavioral Features of Blocks6.5.3. Modeling Service-Based Interfaces Using Standard PortsModeling InterfacesAdding Interfaces to Standard Ports6.5.4. Connecting Standard Ports on an Internal Block Diagram6.5.5. Modeling Block-Defined Methods6.6. Modeling Classification Hierarchies Using Generalization6.6.1. Classification and the Structural Features of a Block6.6.2. Modeling Overlapping Classifications Using Generalization Sets6.6.3. Modeling Variants Using Classification6.6.4. Using Property-Specific Types to Model Context-Specific Block Characteristics6.6.5. Modeling Block Configurations as Specialized BlocksModeling a Configuration on a Block Definition DiagramModeling Configuration Details on an Internal Block Diagram6.6.6. Classification and Behavioral Features6.7. Summary6.8. QuestionsDiscussion Topic
7. Modeling Constraints with Parametrics
7.1. Overview7.1.1. Defining Constraints Using the Block Definition Diagram7.1.2. The Parametric Diagram7.2. Using Constraint Expressions to Represent System Constraints7.3. Encapsulating Constraints in Constraint Blocks to Enable Reuse7.3.1. Additional Parameter Characteristics7.4. Using Composition to Build Complex Constraint Blocks7.5. Using a Parametric Diagram to Bind Parameters of Constraint Blocks7.6. Constraining Value Properties of a Block7.7. Capturing Values in Block Configurations7.8. Constraining Time-Dependent Properties to Facilitate Time-Based Analysis7.9. Using Constraint Blocks to Constrain Item Flows7.10. Describing an Analysis Context7.11. Modeling Evaluation of Alternatives and Trade Studies7.12. Summary7.13. QuestionsDiscussion Topics
8. Modeling Flow-Based Behavior with Activities
8.1. Overview8.2. The Activity Diagram8.3. Actions—The Foundation of Activities8.4. The Basics of Modeling Activities8.4.1. Specifying input and Output Parameters for an Activity8.4.2. Composing Activities Using Call Behavior Actions8.5. Using Object Flows to Describe the Flow of Items between Actions8.5.1. Routing Object Flows8.5.2. Routing Object Flows from Parameter Sets8.5.3. Buffers and Data Stores8.6. Using Control Flows to Specify the Order of Action Execution8.6.1. Depicting Control Logic with Control Nodes8.6.2. Using Control Operators to Enable and Disable Actions8.7. Handling Signals and Other Events8.8. Advanced Activity Modeling8.8.1. Interruptible Regions8.8.2. Modeling Flow Rates and Flow OrderFlow RatesFlow Order8.8.3. Modeling Probabilistic Flow8.8.4. Modeling Pre- and Postconditions and Input and Output States8.9. Relating Activities to Blocks and Other Behaviors8.9.1. Linking Behavior to Structure Using Partitions8.9.2. Specifying an Activity in a Block ContextActivities as Block BehaviorsActivities as Methods8.9.3. Relationship between Activities and Other Behaviors8.10. Modeling Activity Hierarchies Using Block Definition Diagrams8.10.1. Modeling Activity Invocation Using Composite Associations8.10.2. Modeling Parameter and Other Object Nodes Using Associations8.11. Enhanced Functional Flow Block Diagram8.12. Executing Activities8.12.1. Primitive Actions8.12.2. Executing Continuous Activities8.13. Summary8.14. QuestionsDiscussion Topic
9. Modeling Message-Based Behavior with Interactions
9.1. Overview9.2. The Sequence Diagram9.3. The Context for Interactions9.4. Using Lifelines to Represent Participants in an Interaction9.4.1. Events and Occurrences9.5. Exchanging Messages between Lifelines9.5.1. Synchronous and Asynchronous Messages9.5.2. Lost and Found Messages9.5.3. Weak Sequencing9.5.4. Executions9.5.5. Create and Destroy Messages9.6. Representing Time on a Sequence Diagram9.7. Describing Complex Scenarios Using Combined Fragments9.7.1. Basic Interaction Operators9.7.2. Additional Interaction Operators9.7.3. State Invariants9.8. Using Interaction References to Structure Complex Interactions9.9. Decomposing Lifelines to Represent Internal Behavior9.10. Summary9.11. QuestionsDiscussion Topic
10. Modeling Event-Based Behavior with State Machines
10.1. Overview10.2. State Machine Diagram10.3. Specifying States in a State Machine10.3.1. Region10.3.2. State10.4. Transitioning between States10.4.1. Transition FundamentalsTriggerGuardEffectTransition Notation10.4.2. Routing Transitions Using Pseudostates10.4.3. Showing Transitions Graphically10.5. State Machines and Operation Calls10.6. State Hierarchies10.6.1. Composite State with a Single Region10.6.2. Composite State with Multiple (Orthogonal) Regions10.6.3. Transition Firing Order in Nested State Hierarchies10.6.4. Using the History Pseudostate to Return to a Previously Interrupted State10.6.5. Reusing State MachinesEntry and Exit Points on State MachinesSubmachine StatesEntry- and Exit-Point Pseudostates on Composite States10.7. Contrasting Discrete versus Continuous States10.8. Summary10.9. QuestionsDiscussion Topic
11. Modeling Functionality with Use Cases
11.1. Overview11.2. Use Case Diagram11.3. Using Actors to Represent the Users of a System11.3.1. Further Descriptions of Actors11.4. Using Use Cases to Describe System Functionality11.4.1. Use Case RelationshipsInclusionExtensionClassification11.4.2. Use Case Descriptions11.5. Elaborating Use Cases with Behaviors11.5.1. Context Diagrams11.5.2. Sequence Diagrams11.5.3. Activity Diagrams11.5.4. State Machine Diagrams11.6. Summary11.7. QuestionsDiscussion Topics
12. Modeling Text-Based Requirements and Their Relationship to Design
12.1. Overview12.2. Requirement Diagram12.3. Representing a Text Requirement in the Model12.4. Types of Requirements Relationships12.5. Representing Cross-Cutting Relationships in SysML Diagrams12.5.1. Depicting Requirements Relationships Directly12.5.2. Depicting Requirements Relationships Using Compartment Notation12.5.3. Depicting Requirements Relationships Using Callout Notation12.6. Depicting Rationale for Requirements Relationships12.7. Depicting Requirements and Their Relationships in Tables12.7.1. Depicting Requirement Relationships in Tables12.7.2. Depicting Requirement Relationships as Matrices12.8. Modeling Requirement Hierarchies in Packages12.9. Modeling a Requirements Containment Hierarchy12.9.1. The Browser View of a Containment Hierarchy12.10. Modeling Requirement Derivation12.11. Asserting That a Requirement Is Satisfied12.12. Verifying That a Requirement Is Satisfied12.13. Reducing Requirements Ambiguity Using the Refine Relationship12.14. Using the General-Purpose Trace Relationship12.14.1. Reusing Requirements with the Copy Relationship12.15. Summary12.16. QuestionsDiscussion Topics
13. Modeling Cross-Cutting Relationships with Allocations
13.1. Overview13.2. Allocation Relationship13.3. Allocation Notation13.4. Types of Allocation13.4.1. Allocation of Requirements13.4.2. Allocation of Behavior or Function13.4.3. Allocation of Flow13.4.4. Allocation of Structure13.4.5. Allocation of Properties13.4.6. Summary of Relationships Associated with the Term “Allocation”13.5. Planning for Reuse: Specifying Definition and Usage in Allocation13.5.1. Allocating Usage13.5.2. Allocating Definition13.5.3. Allocating Asymmetrically13.5.4. Guidelines for Allocating Definition and Usage13.6. Allocating Behavior to Structure Using Functional Allocation13.6.1. Modeling Functional Allocation of Usage13.6.2. Modeling Functional Allocation of Definition13.6.3. Notational Simplicity: Modeling Functional Allocation Using Allocate Activity Partitions (Swimlanes)13.7. Connecting Functional Flow with Structural Flow Using Functional Flow Allocation13.7.1. Options for Functionally Allocating Flow13.7.2. Allocating an Object Flow to a Connector13.7.3. Allocating Object Flow to Item Flow13.8. Modeling Allocation between Independent Structural Hierarchies13.8.1. Modeling Structural Allocation of Usage13.8.2. Allocating a Logical Connector to a Physical Structure13.8.3. Modeling Structural Allocation of Definition13.9. Modeling Structural Flow Allocation13.10. Evaluating Allocation across a User Model13.10.1. Establishing Balance and Consistency13.11. Taking Allocation to the Next Step13.12. Summary13.13. QuestionsDiscussion Topics
14. Customizing SysML for Specific Domains
14.1. Overview14.1.1. A Brief Review of Metamodeling Concepts14.2. Defining Model Libraries to Provide Reusable Constructs14.3. Defining Stereotypes to Extend Existing SysML Concepts14.3.1. Adding Properties and Constraints to Stereotypes14.4. Extending the SysML Language Using Profiles14.4.1. Specifying a Profile’s Reference Metamodel and Other Inputs14.5. Applying Profiles to User Models in Order to Use Stereotypes14.6. Applying Stereotypes when Building a Model14.6.1. What Happens When Model Elements with Applied Stereotypes Are Specialized?14.7. Summary14.8. QuestionsDiscussion Topics
III. Modeling Examples
15. Water Distiller Example Using Functional Analysis
15.1. Stating the Problem15.2. Defining the Model-Based Systems Engineering Approach15.3. Organizing the Model15.4. Establishing Requirements15.5. Modeling Behavior15.5.1. Simple Behavior15.5.2. Parallel Flow15.5.3. Continuous Flow15.5.4. Allocated Flow15.6. Modeling Structure15.6.1. Defining Distiller’s Blocks in the Block Definition Diagram15.6.2. Defining the Ports on the Blocks15.6.3. Creating the Internal Block Diagram with Parts, Connectors, and Item Flows15.6.4. Allocation of Actions and Flows15.7. Analyzing Performance15.7.1. Item Flow Heat Balance Analysis15.7.2. Resolving Heat Balance15.8. Modifying the Original Design15.8.1. Updating Behavior15.8.2. Updating Allocation and Structure15.8.3. Controlling the Distiller and the User Interaction15.8.4. Developing a User Interface and a Controller15.8.5. Startup and Shutdown Considerations15.9. Summary15.10. Questions
16. Residential Security System Example Using the Object-Oriented Systems Engineering Method
16.1. Method Overview16.1.1. Motivation and Background16.1.2. System Development Process OverviewManage System DevelopmentSpecify and Design SystemDevelop Hardware, Software, Database, and Operational ProceduresIntegrate and Verify System16.1.3. OOSEM System Specification and Design Process16.2. Residential Security Example Overview and Project Setup16.2.1. Problem Background16.2.2. Modeling Conventions and Standards16.2.3. Model Organization16.3. Applying the Method to Specify and Design the System16.3.1. Analyze Stakeholder NeedsCharacterize As-Is System and EnterprisePerform Causal AnalysisSpecify Mission RequirementsCapture Measures of EffectivenessDefine To-Be Domain ModelDefine Enterprise Use Cases16.3.2. Analyze System RequirementsDefine Enterprise ScenariosDefine System ContextCapture Critical System Properties and ConstraintsSpecify Black-Box System RequirementsDefine System State MachineAnalyze System Requirements VariationIdentify System Design Constraints16.3.3. Define Logical ArchitectureDefine Logical DecompositionDefine Interaction between Logical Components to Realize System Activity and/or OperationDefine System Logical Internal Block DiagramSpecify Logical ComponentsDefine Logical Component State Machine16.3.4. Synthesize Candidate Physical ArchitecturesDefine Partitioning CriteriaDefine Logical Node ArchitectureDefine Physical Node ArchitectureDefine Software ArchitectureDefine Data ArchitectureDefine Hardware ArchitectureDefine Operational ProceduresSpecify Component RequirementsDefining Other Architecture Views16.3.5. Optimize and Evaluate AlternativesIdentify Analyses to Be PerformedDefine the Analysis ContextCapture Constraints in Parametric DiagramPerform Engineering Analysis16.3.6. Manage Requirements TraceabilityDefine Specification TreeCapture Text-Based Requirements in ModelEstablish Requirements Relationships and RationaleAnalyze Traceability GapsManaging Requirements Updates16.3.7. Integrate and Verify System16.3.8. Develop Enabling Systems16.4. Summary16.5. Questions
IV. Transitioning to Model-Based Systems Engineering
17. Integrating SysML into a Systems Development Environment
17.1. Understanding the System Model’s Role in a Systems Development Environment17.1.1. Systems Development Environment17.1.2. The System Model as an Integrating Framework17.1.3. Relation of a System Model to an Executable System Model17.2. Integrating the Systems Modeling Tool with Other Tools17.2.1. Classes of Tools in a Systems Development Environment17.2.2. An Interconnected Set of Tools17.2.3. Interface with Requirements Management Tool17.2.4. Interface with Performance Analysis and Other Engineering Analysis Tools17.2.5. Interface with Documentation Generation Tool17.2.6. Interface with Configuration Management Tool17.2.7. Interface with Project Management Tool17.2.8. Interface with Verification Tool17.2.9. Interface with Development Tool17.3. Data Exchange Mechanisms in an Integrated Systems Development Environment17.3.1. Data Exchange Mechanisms17.3.2. Role of Data Exchange StandardsXML Metadata InterchangeApplication Protocol 233Diagram Interchange StandardsModel Transformation17.4. Selecting a System Modeling Tool17.4.1. Tool Selection Criteria17.4.2. Specific Tool Support for the MBSE Method17.4.3. SysML Compliance17.5. Summary17.6. QuestionsDiscussion Topics
18. Deploying SysML into an Organization
18.1. Improvement Process18.1.1. Monitor and Assess18.1.2. Plan the Improvement18.1.3. Define Changes to Process, Methods, Tools, Metrics, and TrainingProcess ChangesMethod ChangesTool ChangesMBSE MetricsTraining Changes18.1.4. Pilot the Approach18.1.5. Deploy Changes Incrementally18.2. Summary18.3. Questions
SysML Reference Guide
A.1. OverviewA.2. Notational ConventionsA.3. Package DiagramA.4. Block Definition DiagramA.5. Internal Block DiagramA.6. Parametric DiagramA.7. Activity DiagramA.8. Sequence DiagramA.9. State Machine DiagramA.10. Use Case DiagramA.11. Requirement DiagramA.12. AllocationA.13. Stereotypes
References

Content preview from A Practical Guide to SysML: The Systems Modeling Language

Chapter 8. Modeling Flow-Based Behavior with Activities

This chapter describes concepts needed to model behavior in terms of the flow of inputs, outputs, and control using an activity diagram. An activity diagram is similar to a traditional functional flow diagram with many additional features to precisely specify a behavior.

Overview

In SysML, an activity is a formalism for describing behavior that specifies the transformation of inputs to outputs through a controlled sequence of actions. The activity diagram is the primary representation for modeling flow-based behavior and is analogous to the functional flow diagram that has been widely used for modeling systems. Activities provide enhanced capabilities over traditional functional flow diagrams, ...

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A Practical Guide to SysML: The Systems Modeling Language

by Sanford Friedenthal, Alan Moore, Rick Steiner

Chapter 8. Modeling Flow-Based Behavior with Activities

Overview

Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
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