This document discusses tailoring model-based systems engineering (MBSE) and the Harmony/SE process for use in the automotive sector. It proposes using a simplified approach focused on modeling individual features rather than entire systems. The tailored process involves three phases: requirements analysis using use case and activity models; system functional analysis using state machines; and design synthesis moving to white-box simulation. Challenges in applying MBSE to automotive include fixed schedules, existing foundations, and feature-focused development. The approach aims to provide quick wins and be deployed with minimal training.

1. Copyright © 2017 by MBSE Training and Consulting Ltd. Published and used by INCOSE UK Ltd and INCOSE with permission.
“hear and I forget. I
see and I remember.
I do and I understand”
(Confucius)
www.executablembse.com
Tailoring the Harmony/SE
MBSE Process for Automotive Sector
Fraser Chadburn (fraser.chadburn@mbsetraining.com)
MBSE Training and Consulting Ltd, Kenilworth, UK
INCOSE UK Annual Systems Engineering Conference 2017
www.mbsetraining.com
INCOSE UK ASEC 2017 “Pushing the Boundaries of Systems Engineering”

2. INCOSE UK ASEC 2017 “Pushing the Boundaries of Systems Engineering”
Objectives of Presentation
• Why Model-based Systems Engineering (MBSE) is important for automotive?
• What is concept-of-operations modelling + “Classic” Harmony/SE process?
• Provide an appreciation where the quick wins are
• How is automotive different from aerospace/defence?
• Lessons/experiences of adapting MBSE/SysML/Harmony for automotive
feature development
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Caveat: Represents authors own opinions
not those of any of his employers

3. INCOSE UK ASEC 2017 “Pushing the Boundaries of Systems Engineering”
Building a solid foundation
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• To have success with MBSE requires:
– Language
– Tool
– People
– Process

4. INCOSE UK ASEC 2017 “Pushing the Boundaries of Systems Engineering”
Yester-year…
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5. INCOSE UK ASEC 2017 “Pushing the Boundaries of Systems Engineering”
Tomorrow’s world / today …
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6. INCOSE UK ASEC 2017 “Pushing the Boundaries of Systems Engineering”
Challenges for automotive manufactures/suppliers
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http://www.redbend.com/data/upl/whitepapers/Cost%20Effective%20Upd
ating%20of%20Software%20in%20Cars%20Whitepaper.pdf

7. INCOSE UK ASEC 2017 “Pushing the Boundaries of Systems Engineering”
Challenges for automotive manufactures/suppliers
• "Road vehicles – Functional safety", ISO 26262
is an international standard for functional
safety of electrical and/or electronic systems in
production automobiles defined by the
International Organization for Standardization
(ISO) in 2011.
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8. INCOSE UK ASEC 2017 “Pushing the Boundaries of Systems Engineering”
Mastering MBSE with Rhapsody
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• Model-based systems
engineering (MBSE) is a systems
engineering methodology which
focuses on creating and
exploiting models as the primary
means of information exchange
between engineers, rather than on
document-based information
exchange
https://en.wikipedia.org/wiki/Model-
based_systems_engineering
INCOSE kicked off an MBSE Initiative in January 2007. Goals
included increased productivity, by minimizing unnecessary
manual transcription of concepts when coordinating the
work of large teams.

9. INCOSE UK ASEC 2017 “Pushing the Boundaries of Systems Engineering”
What is Telelogic/IBM Harmony™
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10. INCOSE UK ASEC 2017 “Pushing the Boundaries of Systems Engineering”
“Classic” Harmony™/SE
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11. INCOSE UK ASEC 2017 “Pushing the Boundaries of Systems Engineering”
A couple of key things about Classic Harmony/SE
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Concept-of-Operations …
… ‘a verbal and graphic statement…of an
organisation’s assumptions or intent in
regard to an operation or series of
operations’ (ISO/IEC/IEEE 2011, p. 4)
‘… represents a system user’s operational
view of a system under development’
(Cohen 1999, 2000)…
… it’s executable MBSE based!
Op
Op Op
Feature A

12. INCOSE UK ASEC 2017 “Pushing the Boundaries of Systems Engineering”
Some of the real-life challenges
• Product schedules are fixed
• Foundations are already built
• Use cases and requirements already in use
• Features are of interest
• Time for training
• Deploying tools
• …
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13. INCOSE UK ASEC 2017 “Pushing the Boundaries of Systems Engineering”
How do we make MBSE and Harmony/SE fit?
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14. INCOSE UK ASEC 2017 “Pushing the Boundaries of Systems Engineering”
Phase 1: Requirements Analysis
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15. INCOSE UK ASEC 2017 “Pushing the Boundaries of Systems Engineering”
Challenges / Opportunities for use case analysis
• Focus on use case models of new “Features” rather system as a whole
• We define requirements for new “Features” from use case analysis, i.e. focus
is on requirements definition/elicitation
• Align the Requirements Analysis to build on top of existing use case practices
in business
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16. INCOSE UK ASEC 2017 “Pushing the Boundaries of Systems Engineering”
What are Features?
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Range Rover Velar_ Safety and Driver Assistance - Land
Rover Australia
https://www.youtube.com/watch?v=8lIn9KvAPJk

17. INCOSE UK ASEC 2017 “Pushing the Boundaries of Systems Engineering”
Use of MBSE for use case analysis
• Loosen rules => More textual step-based Activity Diagrams, allow
extend/include in use case model
• Focus on customer usage (the art of the possible).
• Textual requirements (in DOORS) as formal “currency”
• Provide an alternative open-source toolkit (www.executablembse.com)
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18. INCOSE UK ASEC 2017 “Pushing the Boundaries of Systems Engineering”
Use Activity Model to model customer usage
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19. INCOSE UK ASEC 2017 “Pushing the Boundaries of Systems Engineering”
Textual vs function-based activity diagrams
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20. INCOSE UK ASEC 2017 “Pushing the Boundaries of Systems Engineering”
Generate textual requirements and sync into DOORS
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Derive
requirements
from use
case
steps/guards
Auto-sync
requirements
and
diagrams into
a DOORS
module

21. INCOSE UK ASEC 2017 “Pushing the Boundaries of Systems Engineering”
Creating requirements from use case steps
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22. INCOSE UK ASEC 2017 “Pushing the Boundaries of Systems Engineering”
Benefits of simplified Act approach
• Light-weight, i.e. can be deployed with minimal training
• Can be deployed alongside existing text-based use case analysis as output
currency is the same
• Improves requirement
elicitation / stakeholder
communication
• Aligns with new DOORS
NG “external reqts”
approaches/OSLC
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Copyright: https://www.123rf.com
Stock image

23. INCOSE UK ASEC 2017 “Pushing the Boundaries of Systems Engineering”
Req’ts Analysis in action (www.executablembse.com)
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https://www.youtube.com/watch?v=wZZkhvgArRk

24. INCOSE UK ASEC 2017 “Pushing the Boundaries of Systems Engineering”
Phase 2: System Functional Analysis
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25. INCOSE UK ASEC 2017 “Pushing the Boundaries of Systems Engineering”
System Functional Analysis
• In the System Functional Analysis phase, the focus is on the
translation of the functional requirements into a coherent
description of system functions (operations)
• Each use case is translated into a model and the underlying
requirements verified and validated through model execution
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26. INCOSE UK ASEC 2017 “Pushing the Boundaries of Systems Engineering”
Constraining behaviour using an executable STM
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27. INCOSE UK ASEC 2017 “Pushing the Boundaries of Systems Engineering”
Method is Harmony/SE…
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Build Executable Model of Use Case
[Alternative 1]
[Alternative 3]
Define Use Case Model Context
( UC Internal Block Diagram )
[Alternative 2]
Define UC Functional Flow
( UC Black-Box Activity Diagram )
Derive UC Scenarios
from UC Functional Flow
( UC Black-Box Sequence Diagrams )
Derive UC Functional Flow
from UC Scenarios
( UC Black-Box Activity Diagram )
Define UC Scenarios
( UC Black-Box Sequence Diagrams )
Define Ports And Interfaces
( UC Internal Block Diagram )
Define UC State-Based Behavior
( UC Statechart Diagram )
Derive UC Scenarios
from UC Statechart Diagram
( UC Black-Box Sequence Diagram )
Verify / Validate UC Model
trough Model Execution
Define Ports and Interfaces
( UC Internal Block Diagram )
Derive UC State-Based Behavior
from UC BB-AD and BB-SD’s
( UC Statechart Diagram )
Link
UC Block Properties to Reqs
… but not as you know it

28. INCOSE UK ASEC 2017 “Pushing the Boundaries of Systems Engineering”
Considerations
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I already have activity
diagrams/requirements,
can I use these to create
traced operations?
When I create
operations can I put it
straight into the state-
machine to generate the
SD test scenarios?
Will my state-machine
be too complex if I do it
for a whole feature,
rather than just a use
case?
Can people build
executable models
without deep
tool/method training?

29. INCOSE UK ASEC 2017 “Pushing the Boundaries of Systems Engineering”
Functional Analysis in action (www.executablembse.com)
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https://www.youtube.com/watch?v=LqMjDV6cPmY&t=545s

30. INCOSE UK ASEC 2017 “Pushing the Boundaries of Systems Engineering”
Some conclusions…
• A systematic approach is possible. However, Functional Analysis requires
deeper knowledge
• Tool automation is essential
• “Wing Person” approach
• Process is a bit like unit testing. It finds duplicate, ambiguous, and missing
requirements
• Method generates strawman test cases traced to req’ts
• Automotive engineers gravitate towards a “flavour” of SysML
• Challenges arise where Features are dependent on each others
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31. INCOSE UK ASEC 2017 “Pushing the Boundaries of Systems Engineering”
Strategies for dealing with complexities
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Fig 1 - Using
object-orientated
inheritance to
manage
complexity
Fig 2 – Using straight-to-white
box simulation to manage
complexity
Copyright : rf123.com Andreas Mann

32. INCOSE UK ASEC 2017 “Pushing the Boundaries of Systems Engineering”
Phase 3: Design Synthesis
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33. INCOSE UK ASEC 2017 “Pushing the Boundaries of Systems Engineering”
Design Synthesis
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Op
Op Op
Feature A
Prelim.
Feature Reqts
System Y
Comp
X
Comp
G
Comp
L
Comp
K
Op
Op Op
Feature B
Prelim.
Feature Reqts
Op
Op Op
Feature C
Prelim.
Feature Reqts
Op
Op Op
Feature D
Prelim.
Feature Reqts
State
State
ev1 ev2
Final
Feature Reqts
State
State
ev1 ev2
Final
Feature Reqts
State
State
ev1 ev2
Final
Feature Reqts
State
State
ev1 ev2
Final
Feature Reqts
System X
State
State
ev1 ev2
Comp
A
Comp
B
Comp
C
Comp
D
Comp A
Reqts
Comp B
Reqts
Comp D
Reqts
Comp C
Reqts

34. INCOSE UK ASEC 2017 “Pushing the Boundaries of Systems Engineering”
Lessons learnt in moving to white-box simulation
• Architectures tend towards data-centric / broadcast architecture
• Flow-ports and more continuous-orientated simulations
• Undesirable emergent behavior becomes readily apparent
• Complexity of model is increased but complexity of state machines is reduced
• State machines become more aligned/understood by component owners
• It’s a good point to add real/simulated-HMI
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35. INCOSE UK ASEC 2017 “Pushing the Boundaries of Systems Engineering”
Overall Summary
• The work here is new and represents first impressions
• High-potential for executable MBSE of certain types of systems
• Pull rather than push, from engineers, for executable MBSE
• Challenges similar to requirements management concepts, e.g., abstraction
• Tailoring/limiting the language was really found to help
• Tailoring the tool was found to really help initial deployment
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36. INCOSE UK ASEC 2017 “Pushing the Boundaries of Systems Engineering”
Summary 2/2
• Full “integrated feature” executable MBSE at a large scale, requires high-level
orchestration
• Light-weight techniques surprisingly high value/low cost… the approach to
the “people-process” side is fundamental
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Copyright Iakov Filimonov (rf123 stockimage)

37. INCOSE UK ASEC 2017 “Pushing the Boundaries of Systems Engineering”
Building a solid foundation
38
• To have success with MBSE requires:
– Language
– Tool
– People
– Process

38. INCOSE UK ASEC 2017 “Pushing the Boundaries of Systems Engineering”
Contact Info
• 20 years of modelling experience
(UML/SysML)
– 3 ¾ years in automotive industry using SysML
– 7 ½ years as an IBM Rational Rhapsody/ Jazz
specialist for IBM/Telelogic
– 3 ½ years as product manager for Artisan
Studio UML/SysML tool
– 4 ½ years prior to Artisan using UML
(software), Xerox, WWG/Acterna, DS&S
• Other points: PGCE (Cambridge)
• Live in Kenilworth, Warwickshire
UML4SysML
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Fraser Chadburn B.Sc (Hons)
fraser.Chadburn@mbsetraining.com
www.executablembse.comwww.mbsetraining.com

39. INCOSE UK ASEC 2017 “Pushing the Boundaries of Systems Engineering”
Training
• For paid training, I deliver open-training
on Mastering MBSE with SysML and IBM
Rational Rhapsody in conjunction with
HORIBA MIRA Ltd, Warwickshire, CV10
0TU, UK
• The next course is: 5-7th December 2017
https://www.horiba-mira.com/our-
services/capabilities/model-based-
systems-engineering
UML4SysML
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www.executablembse.comwww.mbsetraining.com
• Free tutorial on “Making Executable MBSE
Simple” is tomorrow!
• I’ll take you through developing a feature
from a blank idea