Practical Guide to SysML (eBook)

The Systems Modeling Language

Sanford Friedenthal, Alan Moore, Rick Steiner (Autoren)

eBook Download: PDF | EPUB

2011 | 2. Auflage
640 Seiten
Elsevier Science (Verlag)
978-0-12-385207-6 (ISBN)

Infos

This book is the bestselling, authoritative guide to SysML for systems and software engineers, providing a comprehensive and practical resource for modeling systems with SysML. Fully updated to cover newly released version 1.3, it includes a full description of the modeling language along with a quick reference guide, and shows how an organization or project can transition to model-based systems engineering using SysML, with considerations for processes, methods, tools, and training. Numerous examples help readers understand how SysML can be used in practice, while reference material facilitates studying for the OMG Systems Modeling Professional (OCSMP) Certification Program, designed to test candidates' knowledge of SysML and their ability to use models to represent real-world systems.

• The authoritative guide for understanding and applying SysML


• Written by the leader and two key members of the OMG SysML standardization team


• Language description, examples, and quick reference guide included

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A Practical Guide to SysML: The Systems Modeling Language is a comprehensive guide for understanding and applying SysML to model systems. The Object Management Group's OMG SysML is a general-purpose graphical modeling language for representing systems that may include combinations of hardware, software, data, people, facilities, and natural objects. SysML supports the practice of model-based systems engineering (MBSE) used to develop system solutions in response to complex and often technologically challenging problems. The book is organized into four parts. Part I provides an overview of systems engineering, a summary of key MBSE concepts, a chapter on getting started with SysML, and a sample problem highlighting the basic features of SysML. Part II presents a detailed description of the SysML language, while Part III illustrates how SysML can support different model-based methods. Part IV discusses how to transition MBSE with SysML into an organization. This book can serve as an introduction and reference for industry practitioners, and as a text for courses in systems modeling and model-based systems engineering. Because SysML reuses many Unified Modeling Language (UML) concepts, software engineers familiar with UML can use this information as a basis for understanding systems engineering concepts. Authoritative and comprehensive guide to understanding and implementing SysML A quick reference guide, including language descriptions and practical examples Application of model-based methodologies to solve complex system problems Guidance on transitioning to model-based systems engineering using SysML Preparation guide for OMG Certified Systems Modeling Professional (OCSMP)

Inhalt

Front Cover 1
Morgan Kaufmann OMG Press 3
A Practical Guide to SysML: The Systems Modeling Language 4
Copyright 5
Contents 6
Preface 18
Book Organization 18
Uses of this Book 19
How to Read This Book 20
Changes from Previous Edition 21
Acknowledgments 22
About the Authors 24
Part I Introduction 26
Chapter 1 - Systems Engineering Overview 28
1.1 Motivation for Systems Engineering 28
1.2 The Systems Engineering Process 29
1.3 Typical Application of the Systems Engineering Process 30
1.4 Multidisciplinary Systems Engineering Team 34
1.5 Codifying Systems Engineering Practice through Standards 35
1.6 Summary 38
1.7 Questions 39
Chapter 2 - Model-Based Systems Engineering 40
2.1 Contrasting the Document-Based and Model-Based Approach 40
2.2 Modeling Principles 46
2.3 Summary 52
2.4 Questions 52
Chapter 3 - Getting Started with SysML 54
3.1 SysML Purpose and Key Features 54
3.2 SysML Diagram Overview 54
3.3 Introducing SysML-Lite 56
3.4 A Simplified MBSE Method 69
3.5 The Learning Curve for SysML and MBSE 72
3.6 Summary 73
3.7 Questions 73
Chapter 4 - An Automobile Example Using the SysML Basic Feature Set 76
4.1 SysML Basic Feature Set 76
4.2 Automobile Example Overview 76
4.3 Automobile Model 77
4.4 Model Interchange 107
4.5 Summary 107
4.6 Questions 108
Part II Language Description 110
Chapter 5 - SysML Language Architecture 112
5.1 The OMG SysML Language Specification 112
5.2 The Architecture of the SysML Language 113
5.3 SysML Diagrams 118
5.4 The Surveillance System Case Study 125
5.5 Organization of Part II 126
5.6 Questions 127
Chapter 6 - Organizing the Model with Packages 128
6.1 Overview 128
6.2 The Package Diagram 129
6.3 Defining Packages Using a Package Diagram 129
6.4 Organizing a Package Hierarchy 131
6.5 Showing Packageable Elements on a Package Diagram 132
6.6 Packages as Namespaces 134
6.7 Importing Model Elements into Packages 134
6.8 Showing Dependencies between Packageable Elements 137
6.9 Specifying Views and Viewpoints 139
6.10 Summary 140
6.11 Questions 141
Chapter 7 - Modeling Structure with Blocks 144
7.1 Overview 144
7.2 Modeling Blocks on a Block Definition Diagram 146
7.3 Modeling the Structure and Characteristics of Blocks Using Properties 148
7.4 Modeling Flows 167
7.5 Modeling Block Behavior 172
7.6 Modeling Interfaces Using Ports 177
7.7 Modeling Classification Hierarchies Using Generalization 192
7.8 Modeling Block Configurations Using Instances 201
7.9 Deprecated Features 203
7.10 Summary 205
7.11 Questions 207
Chapter 8 - Modeling Constraints with Parametrics 210
8.1 Overview 210
8.2 Using Constraint Expressions to Represent System Constraints 212
8.3 Encapsulating Constraints in Constraint Blocks to Enable Reuse 213
8.4 Using Composition to Build Complex Constraint Blocks 215
8.5 Using a Parametric Diagram to Bind Parameters of Constraint Blocks 216
8.6 Constraining Value Properties of a Block 218
8.7 Capturing Values in Block Configurations 220
8.8 Constraining Time-Dependent Properties to Facilitate Time-Based Analysis 220
8.9 Using Constraint Blocks to Constrain Item Flows 222
8.10 Describing an Analysis Context 223
8.11 Modeling Evaluation of Alternatives and Trade Studies 225
8.12 Summary 227
8.13 Questions 228
Chapter 9 - Modeling Flow-Based Behavior with Activities 230
9.1 Overview 230
9.2 The Activity Diagram 231
9.3 Actions—The Foundation of Activities 233
9.4 The Basics of Modeling Activities 234
9.5 Using Object Flows to Describe the Flow of Items between Actions 238
9.6 Using Control Flows to Specify the Order of Action Execution 245
9.7 Handling Signals and Other Events 249
9.8 Structuring Activities 250
9.9 Advanced Flow Modeling 253
9.10 Modeling Constraints on Activity Execution 256
9.11 Relating Activities to Blocks and Other Behaviors 259
9.12 Modeling Activity Hierarchies Using Block Definition Diagrams 265
9.13 Enhanced Functional Flow Block Diagram 268
9.14 Executing Activities 268
9.15 Summary 273
9.16 Questions 274
Chapter 10 - Modeling Message-Based Behavior with Interactions 276
10.1 Overview 276
10.2 The Sequence Diagram 277
10.3 The Context for Interactions 277
10.4 Using Lifelines to Represent Participants in an Interaction 279
10.5 Exchanging Messages between Lifelines 281
10.6 Representing Time on a Sequence Diagram 286
10.7 Describing Complex Scenarios Using Combined Fragments 289
10.8 Using Interaction References to Structure Complex Interactions 295
10.9 Decomposing Lifelines to Represent Internal Behavior 295
10.10 Summary 298
10.11 Questions 299
Chapter 11 - Modeling Event-Based Behavior with State Machines 302
11.1 Overview 302
11.2 State Machine Diagram 303
11.3 Specifying States in a State Machine 303
11.4 Transitioning between States 306
11.5 State Machines and Operation Calls 312
11.6 State Hierarchies 313
11.7 Contrasting Discrete and Continuous States 322
11.8 Summary 324
11.9 Questions 325
Chapter 12 - Modeling Functionality with Use Cases 328
12.1 Overview 328
12.2 Use Case Diagram 328
12.3 Using Actors to Represent the Users of a System 329
12.4 Using Use Cases to Describe System Functionality 330
12.5 Elaborating Use Cases with Behaviors 335
12.6 Summary 339
12.7 Questions 340
Chapter 13 - Modeling Text-Based Requirements and Their Relationship to Design 342
13.1 Overview 342
13.2 Requirement Diagram 343
13.3 Representing a Text Requirement in the Model 345
13.4 Types of Requirements Relationships 347
13.5 Representing Cross-Cutting Relationships in SysML Diagrams 347
13.6 Depicting Rationale for Requirements Relationships 350
13.7 Depicting Requirements and Their Relationships in Tables 351
13.8 Modeling Requirement Hierarchies in Packages 353
13.9 Modeling a Requirements Containment Hierarchy 353
13.10 Modeling Requirement Derivation 354
13.11 Asserting That a Requirement Is Satisfied 356
13.12 Verifying That a Requirement Is Satisfied 357
13.13 Reducing Requirements Ambiguity Using the Refine Relationship 360
13.14 Using the General-Purpose Trace Relationship 363
13.15 Reusing Requirements with the Copy Relationship 363
13.16 Summary 364
13.17 Questions 365
Chapter 14 - Modeling Cross-Cutting Relationships with Allocations 368
14.1 Overview 368
14.2 Allocation Relationship 368
14.3 Allocation Notation 370
14.4 Types of Allocation 372
14.5 Planning for Reuse: Specifying Definition and Usage in Allocation 374
14.6 Allocating Behavior to Structure Using Functional Allocation 377
14.7 Connecting Functional Flow with Structural Flow Using Functional Flow Allocation 383
14.8 Modeling Allocation between Independent Structural Hierarchies 386
14.9 Modeling Structural Flow Allocation 389
14.10 Evaluating Allocation across a User Model 391
14.11 Taking Allocation to the Next Step 391
14.12 Summary 392
14.13 Questions 392
Chapter 15 - Customizing SysML for Specific Domains 394
15.1 Overview 394
15.2 Defining Model Libraries to Provide Reusable Constructs 398
15.3 Defining Stereotypes to Extend Existing SysML Concepts 399
15.4 Extending the SysML Language Using Profiles 404
15.5 Applying Profiles to User Models in Order to Use Stereotypes 406
15.6 Applying Stereotypes when Building a Model 407
15.7 Summary 413
15.8 Questions 414
Part III Modeling Examples 416
Chapter 16 - Water Distiller Example Using Functional Analysis 418
16.1 Stating the Problem – The Need for Clean Drinking Water 418
16.2 Defining the Model-Based Systems Engineering Approach 419
16.3 Organizing the Model 419
16.4 Establishing Requirements 421
16.5 Modeling Structure 434
16.6 Analyze Performance 442
16.7 Modify the Original Design 445
16.8 Summary 454
16.9 Questions 454
Chapter 17 - Residential Security System Example Using the Object-Oriented Systems Engineering Method 456
17.1 Method Overview 456
17.2 Residential Security Example Overview 462
17.3 Applying OOSEM to Specify and Design the Residential Security System 463
17.4 Summary 543
17.5 Questions 544
Part IV Transitioning to Model-Based Systems Engineering 546
Chapter 18 - Integrating SysML into a Systems Development Environment 548
18.1 Understanding the System Model’s Role in the Broader Modeling Context 548
18.2 Tool Roles in a Systems Development Environment 555
18.3 An Overview of Information Flow between Tools 560
18.4 Data Exchange Mechanisms 567
18.5 Data Exchange Applications 573
18.6 Selecting a System Modeling Tool 578
18.7 Summary 579
18.8 Questions 580
Chapter 19 - Deploying SysML into an Organization 582
19.1 Improvement Process 582
19.2 Summary 588
19.3 Questions 588
Appendix A - SysML Reference Guide 590
A.1 Overview 590
A.2 Notational Conventions 590
A.3 Package Diagram 592
A.4 Block Definition Diagram 594
A.5 Internal Block Diagram 600
A.6 Parametric Diagram 602
A.7 Activity Diagram 603
A.8 Sequence Diagram 607
A.9 State Machine Diagram 610
A.10 Use Case Diagram 613
A.11 Requirement Diagram 614
A.12 Allocation 617
A.13 Stereotypes 618
References 620
Index 624

Textauszug

Preface

Systems engineering is a multidisciplinary approach for developing solutions to complex engineering problems. The continuing increase in system complexity is demanding more rigorous and formalized systems engineering practices. In response to this demand, along with advancements in computer technology, the practice of systems engineering is undergoing a fundamental transition from a document-based approach to a model-based approach. In a model-based approach, the emphasis shifts from producing and controlling documentation about the system, to producing and controlling a coherent model of the system. Model-based systems engineering (MBSE) can help to manage complexity, while at the same time improve design quality and cycle time, improve communications among a diverse development team, and facilitate knowledge capture and design evolution.

A standardized and robust modeling language is considered a critical enabler for MBSE. The Systems Modeling Language (OMG SysML™) is one such general-purpose modeling language that supports the specification, design, analysis, and verification of systems that may include hardware, software, data, personnel, procedures, and facilities. SysML is a graphical modeling language with a semantic foundation for representing requirements, behavior, structure, and properties of the system and its components. It is intended to model systems from a broad range of industry domains such as aerospace, automotive, health care, and so on.

SysML is an extension of the Unified Modeling Language (UML), version 2, which has become the de facto standard software modeling language. Requirements were issued by the Object Management Group (OMG) in March 2003 to extend UML to support systems modeling. UML 2 was selected as the basis for SysML because it is a robust language that addresses many of the systems engineering needs, while enabling the systems engineering community to leverage the broad base of experience and tool vendors that support UML. This approach also facilitates the integration of systems and software modeling, which has become increasingly important for today's software-intensive systems.

The development of the language specification was a collaborative effort between members of the OMG, the International Council on Systems Engineering (INCOSE), and the AP233 Working Group of the International Standards Organization (ISO). Following three years of development, the OMG SysML specification was adopted by the OMG in May 2006 and the formal version 1.0 language specification was released in September 2007. Since that time, new versions of the language have been adopted by the OMG. This book is intended to reflect the SysML v1.3 specification, which was close to finalization at the time of this writing. It is expected that SysML will continue to evolve in its expressiveness, precision, usability, and interoperability through further revisions to the specification based on feedback from end users, tool vendors, and research activities. Information on the latest version of SysML, tool implementations of SysML, and related resources, are available on the official OMG SysML web site at http://www.omgsysml.org.

Book Organization

This book provides the foundation for understanding and applying SysML to model systems as part of a model-based systems engineering approach. The book is organized into four parts: Introduction, Language Description, Modeling Examples, and Transitioning to Model-Based Systems Engineering.

Part I, Introduction, contains four chapters that provide an overview of systems engineering, a summary of key MBSE concepts, a chapter on getting started with SysML, and a sample problem to highlight the basic features of SysML. The systems engineering overview and MBSE concepts in Chapters 1 and 2 set the context for SysML, and Chapters 3 and 4 provide an introduction to SysML.

Part II, Language Description, provides the detailed description of the language. Chapter 5 provides an overview of the language architecture, and Chapters 6 through 14 describe key concepts related to model organization, blocks, parametrics, activities, interactions, states, use cases, requirements, and allocations, and Chapter 15 describes the language extension mechanisms to further customize the language. The ordering of the chapters and the concepts are not based on the ordering of activities in the systems engineering process, but are based on the dependencies between the language concepts. Each chapter builds the readers’ understanding of the language concepts by introducing SysML constructs: their meaning, notation, and examples of how they are used. The example used to demonstrate the language throughout Part II is a security surveillance system. This example should be understandable to most readers and has sufficient complexity to demonstrate the language concepts.

Part III, Modeling Examples, includes two examples to illustrate how SysML can support different model-based methods. The first example in Chapter 16 applies to the design of a water distiller system. It uses a simplified version of a classic functional analysis and allocation method. The second example in Chapter 17 applies to the design of a residential security system. It uses a comprehensive object-oriented systems engineering method (OOSEM) and emphasizes how the language is used to address a wide variety of systems engineering concerns, including black-box versus white-box design, logical versus physical design, and the design of distributed systems. While these two methods are considered representative of how model-based systems engineering using SysML can be applied to model systems, SysML is intended to support a variety of other model-based systems engineering methods as well.

Part IV, Transitioning to Model-Based Systems Engineering, addresses how to transition MBSE with SysML into an organization. Chapter 18 describes how to integrate SysML into a systems development environment. It describes the different tool roles in a systems development environment, and the type of data that are exchanged between a SysML tool and other classes of tools. The chapter also describes some of the types of data exchange mechanisms and applications, and a discussion on the criteria for selecting a SysML modeling tool. Chapter 19 is the last chapter of the book, and describes how to deploy MBSE with SysML into an organization as part of an improvement process.

Questions are included at the end of each chapter to test readers’ understanding of the material. The answers to the questions can be found on the following Web site at http://www.elsevierdirect.com/companions/9780123852069.

The Appendix contains the SysML notation tables. These tables provide a reference guide for SysML notation along with a cross reference to the applicable sections in Part II of the book where the language constructs are described in detail.

Uses of this Book

This book is a “practical guide” targeted at a broad spectrum of industry practitioners and students. It can serve as an introduction and reference for practitioners, as well as a text for courses in systems modeling and model-based systems engineering. In addition, because SysML reuses many UML concepts, software engineers familiar with UML can use this information as a basis for understanding systems engineering concepts. Also, many systems engineering concepts come to light when using an expressive language, and as such, this book can be used to help teach systems engineering concepts. Finally, this book can serve as a primary reference to prepare for the OMG Certified System Modeling Professional (OCSMP) exam (refer to http://www.omg.org/ocsmp/).

How to Read This Book

A first-time reader should pay close attention to the introductory chapters including Getting Started with SysML in Chapter 3, and the application of the basic feature set of SysML to the Automobile Example in Chapter 4. The introductory reader may also choose to do a cursory reading of the overview sections in Part II, and then review the simplified distiller example in Part III. A more advanced reader may choose to read the introductory chapters, do a more comprehensive review of Part II, and then review the residential security example in Part III. Part IV is of general interest to those interested in trying to introduce SysML and MBSE to their organization or project.

The following recommendations apply when using this book as a primary reference for a course in SysML and MBSE. An instructor may refer to the course on SysML that was prepared and delivered by The Johns Hopkins University Applied Physics Lab that is available for download at http://www.jhuapl.edu/ott/Technologies//Copyright/SysML.asp. This course provides an introduction to the basic features of SysML so that students can begin to apply the language to their projects. This course consists of eleven (11) modules that use this book as the basis for the course material. The course material for the language concepts is included in the download, but the course material for the tool instruction is not included. Using this course as an example course that introduces the language concepts, the instructor can create a course that includes both the language concepts and tool instruction on how to create and update the modeling artifacts using a selected tool. A shorter version of this course is also included on The Johns Hopkins site which has been used as a full day tutorial to provide an introductory short course on SysML. Refer to the End-User License Agreement included with the download instructions on The Johns Hopkins site for how...

Produkt-Details

• Erscheint lt. Verlag: 22.11.2011
• Sprache: englisch
• Themenwelt: Mathematik / Informatik ► Informatik ► Programmiersprachen / -werkzeuge
• Themenwelt: Informatik ► Software Entwicklung ► Objektorientierung
• Themenwelt: Technik
• ISBN-10: 0-12-385207-2 / 0123852072
• ISBN-13: 978-0-12-385207-6 / 9780123852076