1.
An Introduction to Capella and
Arcadia with Tutorial
Peter L. Jackson
Head of Pillar
Engineering Systems and Design (ESD)
Singapore University of Technology and Design
6/30/2019 Capella Webinar 2019 1

2.
Overview of Webinar
• Systems engineering and SysML
• Systems architecture and Capella
• Attractive features of Capella
• Motivation for tutorial
• Overview of tutorial
• Additional resources and link to tutorial
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3.
What is Systems Engineering?
Systems engineering is the process by which
we understand a complex need and create
elegant and harmonious solutions to meet that
need.
P. Jackson
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4.
Systems Architecting vs
Systems Engineering
• Systems architecting is responsible for
the conceptual design
• Systems engineering is responsible for
the full cycle of design-build-test-deploy
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5.
Why Model-Based Systems
Engineering?
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Document-centric systems engineering Model-based systems engineering
Computer aided design/manufacturingDrafting
Analogous to:

6.
Document-Centric Systems
Engineering
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7.
Model-Based Systems
Engineering (MBSE)
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Systems
model
Model
libraries
Requirements
management
Project
management
Configuration
management
Document
generation
Simulation
and test
Software
engineering
Hardware
engineering

8.
Anticipated Benefits of MBSE
• More rigorous means of information
capture
• Enhanced communications
• Reduced development risk
• Improved quality
• Increased productivity
• Enhanced knowledge transfer
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Friedenthal, Moore, and Steiner. 2008. A Practical Guide to SysML, The Systems Modeling Language. Morgan Kaufmann
Publishers.

9.
MBSE Tools
• SysML (the Systems Modeling Language)
is an extension to UML (the Unified
Modeling Language) which is becoming
an industry standard for systems
engineering
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10.
Why SysML?
• Standard language endorsed by
professional societies
• Growing adoption within industry for
larger and larger projects
• Well-supported with both open-source
and commercial software
• Growing connections with management,
modeling, and analysis tools
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11.
The Four Pillars of SysML
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Requirements Behavior
Structure Parametrics
Requirements diagram
Activity diagram
Interaction diagram
State machine diagram
Block definition diagram
Internal block diagram
Package diagram
Parametric diagram
Use case diagram

12.
Cross-Cutting Relations in SysML
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Requirements Behavior
Structure Parametrics
“satisfied by”
“bind values with”
“allocated to”
“verify”

13.
Why Not SysML?
• Teaching course in Engineering Systems
Architecture (ESA) for Junior engineering
students
• Focus on architecture (design)
• Core class for all ESD students at SUTD
• Systems engineering more suitable for
graduate study
• Seek modeling tool for systems architecture
• SysML is ‘overkill’ for systems architecture
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14.
Overview of Webinar
• Systems engineering and SysML
• Systems architecture and Capella
• Attractive features of Capella
• Motivation for tutorial
• Overview of tutorial
• Additional resources and link to tutorial
6/30/2019 Capella Webinar 2019 14

15.
Document-Centric Systems
Architecture
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System
architecture
documents

16.
Model-Based Systems
Architecture
• Arcadia: a process
for conducting
systems
architecting
1. Operational analysis
2. Systems analysis
3. Logical architecture
4. Physical architecture
• Capella: a
modeling language
for systems
architecture
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17.
The Arcadia Viewpoints
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Adopted by
Thales and
supported by
Capella
modeling tool

18.
The Arcadia Process
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Arcadia Process Activity
Operational Analysis Think through what your users need to accomplish
(e.g. journey maps) with multiple scenarios
System Analysis Repeat those scenarios but now show what
functions or services the system could provide
Logical Architecture Chunk the system functionality into major blocks
(sub-systems) with interfaces
Physical
Architecture
Map the logical architecture to physical
components; prepare to release for detailed design

19.
Overview of Webinar
• Systems engineering and SysML
• Systems architecture and Capella
• Attractive features of Capella
• Motivation for tutorial
• Overview of tutorial
• Additional resources and link to tutorial
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20.
Attractive Features of Capella
• Enforces a methodology (Arcadia)
• SysML is methodology-agnostic
• Methodology is repetitive: faster learning
• Simpler than SysML
• Open license for core features
• Will have wide user base
• Eclipse-based
• Robust graph-based architecture
• Supports many common diagramming tools
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21.
Capella: Supported Diagrams
• Operational Diagrams
• Capability Diagrams
• Dataflow Diagrams
• Architecture Diagrams
• Tree Diagrams
• Sequence Diagrams
• Modes and States Diagrams
• Software Classes and Interface Diagrams
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22.
Overview of Webinar
• Systems engineering and SysML
• Systems architecture and Capella
• Attractive features of Capella
• Motivation for tutorial
• Overview of tutorial
• Additional resources and link to tutorial
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23.
Our Educational Goals
• Target audience: Junior year engineering
students
• Teach the first three levels of the Arcadia
approach (Operational Analysis, System
Analysis, and Logical Architecture)
• Teach the Capella software with a simple
example
• Teach additional diagramming tools using
Capella
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24.
Overview of Webinar
• Systems engineering and SysML
• Systems architecture and Capella
• Attractive features of Capella
• Motivation for tutorial
• Overview of tutorial
• Additional resources and link to tutorial
6/30/2019 Capella Webinar 2019 24

25.
Landing Page of Tutorial
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26.
Getting Started
• Basic instructions for installing
Capella and setting up initial
workspace and project
• PC-based instructions
• (Request author for Mac-based)
• Introduction to Eclipse-based user
interface
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27.
Operational Analysis
• Introduce actors and operational
entities
• Identify mission and required
capabilities
• Familiarize user with scenario
creation process
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28.
Operational Capability and
Mission Statement
• Our mission is to design a toy catapult to safely amuse
a three-year old grandchild, creating an opportunity
for parent and child to play together in a way that
delights both parent and child.”
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29.
Simple Operational Analysis
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30.
Use Cases or ‘Scenarios’?
• Capella uses “scenarios” to describe the
modeling activity
• Can include journey maps during operational
analysis phase (before the system has been
identified)
• Can include use cases during system analysis
phase (once you have a system concept)
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31.
How to Describe Scenario
Behavior
• Capella encourages use of Sequence
diagrams to describe behaviors
• I prefer Activity Diagrams (with
swimlanes)
• With a little work, we can adapt Capella to
create Activity Diagrams
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32.
System Analysis
• From required capabilities, explore
use cases using activity diagrams
with swimlanes
• Summarize system architecture in a
single diagram
• Highlight functional chains
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33.
Identify Required Capabilities
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34.
Child Plays With
Toy Scenario
• Basic load and
launch scenario
• User swimlane on
left
• System swimlane in
middle
• Auxiliary actors,
external systems on
right
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35.
Parent Teaches
Scenario
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• Dad has idea to
trigger catapult
from passing toy
train
• Add users on
left, external
systems on right

36.
Discovery
• It would be nice to trigger the catapult directly,
by child, and indirectly, by passing toy train
• Easiest for child would be vertical downward motion
• Toy train would need horizontal trigger motion
• We have identified a design opportunity:
• Greater entertainment if trigger mechanism is
responsive to both horizontal and vertical motions
• (Motivates a concept generation cycle: how
could we design such a trigger?)
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37.
System Architecture for Toy
Catapult
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38.
‘Single Shot’ Functional Chain
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39.
‘Train Shot’ Functional Chain
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40.
Logical Architecture
• Identify logical subsystems
• Allocate functions to subsystems
• Detailing where necessary
• Conduct modal analysis
• Identify system states and transitions
• Summarize logical architecture
• Display functional chains
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41.
Identify Logical Subsystems
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42.
Allocate Behavior to
Subsystems
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43.
Conduct Modal Analysis
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Set the stage: Students will
take course in simulation next
semester

44.
Summarize Logical
Architecture
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45.
‘Single Shot’ Chain
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46.
‘Train Shot’ Chain
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47.
Physical Architecture
• Not detailed by this tutorial
• Out of scope for ESA course
• Sketch main steps of approach
only
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48.
Document Generation
• How to export all of the
diagrams as images
• How to export the architecture
model in HTML format for non-
architects to browse
• A powerful feature
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49.
Class Diagram
• How to create three useful styles
of diagrams using the Capella
class diagram format
• Concept Diagram
• Concept Classification Diagram
• Influence Diagram
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50.
Context Diagram
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51.
Concept
Classi-
fication
Diagram
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52.
Influence Diagram
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53.
Overview of Webinar
• Systems engineering and SysML
• Systems architecture and Capella
• Attractive features of Capella
• Motivation for tutorial
• Overview of tutorial
• Additional resources and link to tutorial
6/30/2019 Capella Webinar 2019 53

54.
Resources
• Roques, Pascal. 2018. Systems Architecture Modeling with
the Arcadia Method: A Practical Guide to Capella, 1st
Edition, ISTE Press ISBN 978-1785481680
• Voirin, J-L. 2018. Model-based System and Architecture
Engineering with the Arcadia Method (Implementation of
Model Based System Engineering), ISTE Press, ISBN 978-
1785481697
• Tutorial (Jackson and Arikan)
• https://esd.sutd.edu.sg/40014-capella-tutorial/
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55.
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