INCOSE Model-Based Systems Engineering (MBSE)
CubeSat Modeling Efforts
Dave Kaslow
International Council on Systems Engineering (INCOSE)
Space Systems Working Group (SSWG)
Copyright © 2015 INCOSE
SSWG. All rights reserved
1
GSFC Systems Engineering
Seminar - June 2015
Agenda
•
Project Objectives and Team
•
INCOSE MBSE Initiative and Roadmap
•
What is MBSE
•
SSWG Challenge Project
•
CubeSat Reference Model Development and Distribution
•
CubeSat Reference Model Architecture
•
Next Steps
•
References
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GSFC Systems Engineering
Seminar - June 2015
Project Objectives
Prove-out MBSE methodology on a CubeSat
Provide a CubeSat Reference Model
that CubeSat teams can use as a
starting point for their
mission specific CubeSat model
Copyright © 2015 INCOSE
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GSFC Systems Engineering
Seminar - June 2015
Team Composition
Aerospace Students and Professors
JPL and NASA Engineers
Engineers and Software Developers from NASA Centers,
Aerospace Companies, and Modeling and Simulation Tool Providers
Telecons every Friday at 1pm east coast time
Meeting materials and links to meeting recordings in Google docs
Conference papers posted in INCOSE Space Systems
Working Group Web Site
Email me to be included on the email reflector list:
david.kaslow@gmail.com
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GSFC Systems Engineering
Seminar - June 2015
INCOSE MBSE Initiative - Genesis, Flow, Interaction
International Council on
Systems Engineering (INCOSE)
Working Groups
Object
Oriented
SE Method.
(OOSEM) [5]
2000
Space
Systems
2000
SE Vision 2020 [1]
2007
MBSE & SysML
Systems
Modeling
Language
(SysML) [4]
2006
Unified
Modeling
Language
(UML)
MBSE Initiative &
Roadmap [2] [3]
MBSE Challenge Teams
Space System Modeling
Copyright © 2015 INCOSE
SSWG. All rights reserved
Object Modeling
Group (OMG)
5
SSWG
Challenge
Project
GSFC Systems Engineering
Seminar - June 2015
MBSE Roadmap
Well
Defined
MBSE
Extending Maturity
and Capability
Distributed and secure model
repositories crossing multiple domains
Defined MBSE theory,
ontology, and formalisms
Maturity
Institutionalized
MBSE Across
Academia /
Industry
Architecture model integrated with
simulation, analysis, and visualization
Matured MBSE methods and metrics
Integrated system / HW / SW models
Ad Hoc MBSE
Document Centric
Emerging MBSE Standards
2010
2015
2020
2025
Adapted from [3]
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GSFC Systems Engineering
Seminar - June 2015
MBSE
•
INCOSE Systems Engineering Vision [1]
– MBSE: Formalized application of modeling to support system requirements,
design, analysis, verification, and validation activities
•
Survey of Model Based Systems Engineering Methodologies [6], [7]
– e.g. INCOSE OOSEM, IBM Telelogic Harmony SE, Vitech MBSE
– MBSE: A collection of related processes, methods, and tools
•
Object Management Group [4]
– OMG SysML: A graphical modeling language for modeling complex systems
including hardware, software, information, personnel, procedures, and
facilities
– SysML is just a language
– SysML is not a methodology or a tool
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GSFC Systems Engineering
Seminar - June 2015
MBSE
•
INCOSE OOSEM [5] [8]
– Objectives
• Capture and analyze requirements and design information
• Integrate MBSE methods with oo software and other engineering
methods
• Support system level reuse and design evolution
‒ Activities
• Analyze needs
• Define system requirements
• Define logical architecture
• Synthesize allocated architectures
• Optimize, evaluate alternatives • Validate and verify system
Copyright © 2015 INCOSE
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GSFC Systems Engineering
Seminar - June 2015
MBSE
INCOSE Object-Oriented Systems
Engineering Methodology
System Modeling
Tools
Interfaces with
Other Models
SysML
Structure
Diagrams
Model
Elements
Block Definition
Internal Block
Blocks
Requirements
Diagram
Actors
Parametric
Diagram
Flow
Behavior
Diagrams
Constraint
Blocks
Use Case
Activity
Sequence
State Machine
Signals
Copyright © 2015 INCOSE
SSWG. All rights reserved
Package
Diagram
Ports
…
Diagrams are
views of the
underlying
system model
9
Block
Properties
Parts
References
Values
Constraints
Operations
…
A Block is the
basic unit of
structure
GSFC Systems Engineering
Seminar - June 2015
MBSE
Model Based Systems Engineering
Performing SE with models
System and subsystem level models
Integration of models and simulations
Authoritative, integrated repository
of information from procurement
through operations
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SSWG. All rights reserved
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GSFC Systems Engineering
Seminar - June 2015
SSWG Challenge Project
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SSWG. All rights reserved
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GSFC Systems Engineering
Seminar - June 2015
SSWG Challenge Project
INCOSE MBSE
Challenge Project
Initiated in 2007
Recent Efforts (Phase 3)
MBSE CubeSat Project
Phase 1 [9]
CubeSat Framework
Enterprise Modeling
for CubeSats [11]
Preliminary RAX Model
INCOSE SSWG
2007-2010
Phase 0
Phase 2 [10]
RAX Behavior Modeling
Power, Comm, State
RAX CubeSat Model
Trade Studies [12]
Modeled a SpaceSystem
in SysML
Current Efforts (Phase 4)
Hypothetical FireSat
Space Mission Analysis
and Design (SMAD)
Develop a CubeSat
MBSE Reference
Model [13] [14]
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SSWG. All rights reserved
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GSFC Systems Engineering
Seminar - June 2015
MBSE CubeSat Project
Initiated 2011
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GSFC Systems Engineering
Seminar - June 2015
Radio Aurora Explorer (RAX) Mission
•
Michigan Exploration Lab and SRI
International mission
•
Studies formation of magnetic field
aligned plasma irregularities in the
lower polar ionosphere
•
Radar signal is transmitted by
Incoherent Scatter Radar site in
Poker Flat, Alaska and received by
RAX’s radar receiver
• Science data processed on-board,
compressed, transmitted to the
primary ground station and control
center in Ann Arbor, Michigan
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GSFC Systems Engineering
Seminar - June 2015
Radio Aurora Explorer (RAX) Mission
STK-generated schematic of RAX spacecraft with vectors pointing towards the
experimental zone, Poker Flat, AK, the sun, and along the Earth’s magnetic field.
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GSFC Systems Engineering
Seminar - June 2015
Tools
•
No Magic
– Magic Draw: Graphical SysML modeling tool
– Cameo Simulation Toolkit: Time-step execution of behavior models
•
InterCAX
– Pararamagic: Plug-in modudle for MagicDraw - wraps external models
– Systems LIfecycle Management (SLIM): Version control and config mgt
•
Analytical Graphics
– Systems Tool Kit: Simulation and visualization of spacecraft behavior
•
Phoenix Integration
– Model Center: Graphical environment for creating simulation workflows by
integrating of simulation models including STK scenarios.
– MBSE Analyzer: Execution of parametric diagrams
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GSFC Systems Engineering
Seminar - June 2015
Phase 2
Model Based Systems Engineering (MBSE) Applied to
Radio Aurora Explorer (RAX) CubeSat Mission
Operational Scenarios
2013 IEEE Aerospace Conference
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GSFC Systems Engineering
Seminar - June 2015
Phase 2 - RAX Behavior Modeling - Power, Comm, State
System Model
No Magic - MagicDraw
SysML Models
Block Definition Diagram
Internal Block Diagram
Activity Diagram
State Machine Diagram
Parametric Diagram
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GSFC Systems Engineering
Seminar - June 2015
Phase 2 - RAX Behavior Modeling - Power, Comm, State
Orbit Dynamics
Power
‒ Power gathering
‒ Subsystem power usage
‒ Orbit and attitude
‒ Data collection and ground
station access opportunities
‒ Solar power collection
Phoenix Integration
ModelCenter
Analytical Graphics
Systems Tool Kit
‒ Animation of SysML parametric
diagrams .
‒ Interface with STK and MATLAB
‒ Mission modeling, analysis
and visualization
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GSFC Systems Engineering
Seminar - June 2015
Phase 2 - RAX Behavior Modeling - Power, Comm, State
Communication Download
‒ Signal to noise ratio
‒ Downlink data rate
‒ Available power
InterCAX
ParaMagic
‒ Execution of constraint behaviors
in SysML parametric diagrams
•
Trades of data downlink rate, available power, and signal to noise ratio
– Data downlink rate and available power => Max feasible SNR
– Data downlink rate and desired SNR => Min feasible power required
– Available power and desired SNR => Max feasible data downlink rate
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GSFC Systems Engineering
Seminar - June 2015
Phase 2 - RAX Behavior Modeling - Power, Comm, State
Mission System Activity
‒ Behavior and interactions
No Magic
Cameo Simulation Toolkit
‒ Animation of SysML state
machines and activity models
•
Model commanding of subsystems for state changes and activities as
directed by a command sequence
– In-view of ground station uplink of command sequence
– In-view of mission object – collect mission data
– In-view of ground station – downlink mission data
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GSFC Systems Engineering
Seminar - June 2015
Phase 3
Integrated Model-Based Systems Engineering (MBSE)
Applied to the Simulation of a CubeSat Mission
2014 IEEE Aerospace Conference
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GSFC Systems Engineering
Seminar - June 2015
RAX CubeSat Model Trade Studies
Vehicle block definition diagram
Model: Power collection and management - Data collection and management
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GSFC Systems Engineering
Seminar - June 2015
RAX CubeSat Model Trade Studies
Mapping of requirements to value properties of the Vehicle block
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GSFC Systems Engineering
Seminar - June 2015
RAX CubeSat Model Trade Studies
State Diagrams
Parametric Diagrams
• Orbit
• Get States
• Solar
• Power Collection
• Experiment
• Download
• Update Energy
Models behavior
in response to
internal and
external events
• Update Data
• Update Download
Activity Diagrams
• Run Operation
‒ Steps through time
• Update States
• Send Signals
‒ Controls update
of state values
• Update State Values
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Defines actions in the
activity along with the
flow of input, output, and
control
Mapped to analytical
and simulation models
that estimate RAX
performance
Use of SysML diagrams in RAX CubeSat
mission simulation.
25
GSFC Systems Engineering
Seminar - June 2015
RAX CubeSat Model Trade Studies
Trade Studies
Values Studied
Performance
Metric
Solar Panel Area
•
•
•
Nominal: 18.2 cm2/side
½ of nominal
¼ of nominal
On-board
energy
Max Battery
Capacity
•
•
Nominal: 115,000 J
Reduced: 100,000 J
On-board
energy
Orbital Altitude
•
•
•
Nominal: 811 km x 457 km
Low: 593 km x 250 km
High: 1311 km x 932 km
Quantity of data
downloaded
Ground Station
Network
•
•
•
Ann Arbor & Menlo Park
Ann Arbor & Fairbanks
Fairbanks & Menlo Park
Quantity of data
downloaded
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GSFC Systems Engineering
Seminar - June 2015
RAX CubeSat Model Trade Studies
120000
2
Energy
Sun state
Sun State
Energy (J)
110000
100000
1
90000
80000
0
0
20
40
60
Time (min.)
80
100
Time history of energy state of nominal RAX CubeSat design
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GSFC Systems Engineering
Seminar - June 2015
RAX CubeSat Model Trade Studies
1
2
Downloaded data
Download state
0.6
Download state
Downloaded data (MB)
0.8
1
0.4
0.2
0
0
0
20
40
60
Time (min.)
80
100
Time history of download state of nominal RAX CubeSat design.
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GSFC Systems Engineering
Seminar - June 2015
RAX CubeSat Model Trade Studies
120000
Nominal
1/2 solar panel
1/4 solar panel
Max energy level
Min energy level
Energy (J)
110000
100000
90000
80000
0
20
40
60
Time (min.)
80
100
Impact of solar panel sizing on energy state
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GSFC Systems Engineering
Seminar - June 2015
RAX CubeSat Model Trade Studies
Selection of ground stations for data download
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GSFC Systems Engineering
Seminar - June 2015
Phase 4
Develop and Distribute a CubeSat Reference Model
2015 IEEE Aerospace Conference
2015 Space Symposium
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GSFC Systems Engineering
Seminar - June 2015
Development of the CubeSat Reference Model
Model Scope
Out Reach
Mission
Stakeholders
Working Groups
Symposiums
Workshops
Needs, Objectives
Measures of
Effectiveness
Constraints
Model
Development
SSWG
Team
Tool Set
CubeSat Reference Model
Life Cycles
Conception to
retirement
Phases of
Operations
Launch, Early ops
Normal ops
Copyright © 2015 INCOSE
SSWG. All rights reserved
Plan
Standards &
Conventions
Guidance
Foundations
Cal Poly CubeSat Design Spec [15]
INCOSE Sys. Eng. Handbook [16]
NASA Sys. Eng. Handbook [17]
Management
and Sharing
Validation
Space Mission Engineering –
The New SMAD [18]
32
GSFC Systems Engineering
Seminar - June 2015
Distribution and Use of the CubeSat Reference Model
SSWG
CubeSat
Reference Model
Video of Model
Walk-Through
Copyright
and License
Distribution
Mechanisms
MagicDraw
ZIP File
XMI File
OpenMBEE
Teamwork Server
Copyright © 2015 INCOSE
SSWG. All rights reserved
User
Feedback
Mechanisms
Users
CubeSat Reference Model
CubeSat Team
Classroom
Mission Specific
CubeSat Model
Example
CubeSat Model
33
GSFC Systems Engineering
Seminar - June 2015
Development of a Mission Specific CubeSat Model
CubeSat
Reference
Model
Validation and
Verification
Strategies
Mission
Assurance
Objectives and
Strategies
Trade Studies
Requirements
Verification
Copyright © 2015 INCOSE
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Mission Specific
Stakeholders Use
Cases, Viewpoint
Stages
Mission Specific Model
Model
Elements
Diagrams
Concept
Development
Production
Operational
Retirement
Space and Ground
System Components
Library of
components to swap
in and out of model
34
Interface with
Modeling and
Simulation Tools
GSFC Systems Engineering
Seminar - June 2015
Validation and Verification
Rqts and Design Validation
CubeSat Reference Model
Test System
Requirements and
Logical Architecture
CubeSat Reference
Test Model
Test Requirements
and Objectives
SW & HW
Models & Simulators
Mission CubeSat Model
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Rqts and Design Validation
35
GSFC Systems Engineering
Seminar - June 2015
Validation and Verification
CubeSat Reference Model
Rqts and Design Validation
Test System
CubeSat Mission Model
Requirements and
Logical Architecture
Mission CubeSat
Model
Test Requirements
and Objectives
SW & HW
Models & Simulators
Physical Architecture
Build – Validate - Verify
Mission
CubeSat
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As-Built
Mission
CubeSat
GSFC Systems Engineering
Seminar - June 2015
Measures of Effectiveness and Requirements
Concept Phase
Needs Analysis
MOE / MOP Definition
and Validation
Model subsystems
and components
needed for
Trade Studies
Production Phase
System Validation
Stakeholder Needs,
MOEs, MOPs
Copyright © 2015 INCOSE
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Stakeholder
Needs, Objectives,
Constraints
Concept and
Development Phase
Requirements
Analysis and
Definition
Mission Enterprise
MOEs - Requirements
Space System
Ground System
Production Phase
MOPs - Rqts
MOPs - Rqts
Requirements
Verification
Subsystems
Subsystems
Components
Components
37
GSFC Systems Engineering
Seminar - June 2015
CubeSat System Reference Model Architecture
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GSFC Systems Engineering
Seminar - June 2015
CubeSat Stakeholders
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GSFC Systems Engineering
Seminar - June 2015
CubeSat Mission Enterprise
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GSFC Systems Engineering
Seminar - June 2015
CubeSat Logical Space System
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GSFC Systems Engineering
Seminar - June 2015
CubeSat Logical Ground System
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GSFC Systems Engineering
Seminar - June 2015
Next Steps and References
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GSFC Systems Engineering
Seminar - June 2015
Next Steps
•
Develop model glossary / ontology
•
Populate model with example:
– Stakeholder needs, objectives, constraints
– Mission and system requirements
– MOEs and MOPs
•
Demonstrate validation of MOEs and MOPs
•
Provide the model to university aerospace program
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GSFC Systems Engineering
Seminar - June 2015
References
[1] Systems Engineering Vision 2020, INCOSE –TP_2004-004-02, ver. 2/03,September 2007.
[Online]. Available:
http://oldsite.incose.org/ProductsPubs/pdf/SEVision2020_20071003_v2_03.pdf
[2] International Council on Systems Engineering (INCOSE), “MBSE Initiative,” January 2007.
[Online] Available:
https://connect.incose.org/
[3] MBSE Roadmap. MBSE Wiki, INCOSE MBSE IW 2012. MBSE Wiki. [Online} Available:
http://www.omgwiki.org/MBSE/lib/exe/fetch.php?media=mbse:mbse_iw_2012-introduction2012-01-21-friedenthal-c.pptx
[4] Object Management Group (OMG), OMG Website. [Online]. Available:
http://www.omgsysml.org/
[5] Object Management Group (OMG), OMG Wiki. [Online]. Available:
http://www.omgwiki.org/MBSE/doku.php?id=mbse:incoseoosem
[6] Survey of Model-Based Systems Engineering (MBSE) Methodologies. INCOSE-TD-2007003-01, Ver. B. 10 June 2008. [Online]. Available:
https://oldsite.incose.org/ProductsPubs/pdf/techdata/MTTC/MBSE_Methodology_Survey_2
008-0610_RevB-JAE2.pdf
Copyright © 2015 INCOSE
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GSFC Systems Engineering
Seminar - June 2015
References
[7] Additional Methodologies Identified as Gaps since 2008 INCOSE Survey. MBSE Wiki,
Metrics and Methodologies [Online]. Available:
http://www.omgwiki.org/MBSE/doku.php?id=mbse:methodology
[8] S. Friedenthal, A. Moore, R. Steiner, A Practical Guide to SysML. 3rd ed. Elsevier, Waltham,
MA, 2014
[9] S. Spangelo, D. Kaslow, C. Delp, B. Cole, L. Anderson, E. Fosse, B. Gilbert, L. Hartman, T.
Kahn, and J. Cutler, “Applying Model Based Systems Engineering (MBSE) to a Standard
CubeSat,” in Proceedings of IEEE Aerospace Conference, Big Sky, MT, March 2012.
[10] S. Spangelo, L. Anderson, E. Fosse, L Cheng, R. Yntema, M. Bajaj, C. Delp, B. Cole, G.
Soremekun, D. Kaslow, and J. Cutler, “Model Based Systems Engineering (MBSE) Applied
to Radio Explorer (RAX) CubeSat Mission Operational Scenarios,” Proceedings of IEEE
Aerospace Conference, Big Sky, MT, March 2013.
[11] L. Anderson, B. Cole, R. Yntema, M. Bajaj, S. Spangelo, D. Kaslow, C. Lowe, E. Sudano,
M. Boghosian, R. Reil, S. Asundi, and S. Friedenthal, “Enterprise Modeling for CubeSats,”
Proceedings of IEEE Aerospace Conference, Big Sky, MT, March 2014.
[12] D. Kaslow, G. Soremekun, H. Kim, S. Spangelo, “Integrated Model-Based Systems
Engineering (MBSE) Applied to the Simulation of a CubeSat Mission”, Proceedings of IEEE
Aerospace Conference, Big Sky, MT, March 2014.
Copyright © 2015 INCOSE
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GSFC Systems Engineering
Seminar - June 2015
References
[13] D. Kaslow, L. Anderson, S. Asundi. B. Ayres, C. Iwata, B. Shiotani, R. Thompson,
“Developing a CubeSat Model-Based System Engineering (MBSE) Reference Model –
Interim Status”, Proceedings of IEEE Aerospace Conference, Big Sky, MT, March 2015.
[14] D. Kaslow, L. Anderson, S. Asundi. B. Ayres, C. Iwata, B. Shiotani, R. Thompson,
“Developing and Distributing a CubeSat Model-Based System Engineering (MBSE)
Reference Model ”, Proceedings of the 31st Space Symposium, Colorado Springs, CO,
April 2015.
[15] CubeSat Design Specification, rev. 13, The CubeSat Program, Cal Poly SLO, February
2014.
[16] INCOSE Systems Engineering Handbook, v. 3.2.2, October 2011, INCOSE-TP-2003-00203.2.2.
[17] NASA Systems Engineering Handbook, rev. 1, December 2007, NASA/SP-2007-6105
Rev1.
[18] J.R. Wertz, D. Everett, and J. Puschell, Eds., Space Mission Engineering: The New SMAD,
(Space Technology. Library, Volume 28), Hawthorne, CA, Microcosm Press, 2011
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GSFC Systems Engineering
Seminar - June 2015