SLIDE 1 Reconfiguration in Cyber-Physical Systems
Sebastian Wätzoldt
System Analysis and Modeling Group
SLIDE 2
Motivation:
Reconfiguration in Cyber-Physical Systems
■ “Cyber-Physical Systems (CPS) are integrations of computation with physical processes.” [Lee2008] ■ “[CPS] … embed software, which: □ Record physical data via sensors □ Affect physical processes using actuators □ Actively interact with physical and digital world □ Are connected with one another and in global networks □ Use globally available data and services”
[acatech2011]
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SLIDE 3 Sebastian Wätzoldt | Reconfiguration in Cyber-Physical Systems | HPI Symposium @ SAP
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[acatech2011]
Motivation:
Reconfiguration in Cyber-Physical Systems
SLIDE 4 Sebastian Wätzoldt | Reconfiguration in Cyber-Physical Systems | HPI Symposium @ SAP
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[IEEESpectrumNov2012] http://spectrum.ieee.org/green-tech/advanced-cars/all-aboard-the-robotic-road-train
Motivation:
Reconfiguration in Cyber-Physical Systems
SLIDE 5 Sebastian Wätzoldt | Reconfiguration in Cyber-Physical Systems | HPI Symposium @ SAP
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[IEEESpectrumNov2012] http://spectrum.ieee.org/green-tech/advanced-cars/all-aboard-the-robotic-road-train
Motivation:
Reconfiguration in Cyber-Physical Systems
SLIDE 6 Sebastian Wätzoldt | Reconfiguration in Cyber-Physical Systems | HPI Symposium @ SAP
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[IEEESpectrumNov2012] http://spectrum.ieee.org/green-tech/advanced-cars/all-aboard-the-robotic-road-train
Motivation:
Reconfiguration in Cyber-Physical Systems
SLIDE 7 Software adaptation is (1) the adaptation of a software system or (2) the processes and activities related to the adaptation of a software system.
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■ Parameter adaptation vs. compositional adaptation □ “Parameter adaptation modifies program variables that determine behavior.” [McKinley2004] □ “[…] compositional adaptation exchanges algorithmic or structural system components with others that improve a program’s fit to its current environment.” [McKinley2004] ■ Static adaptation vs. dynamic adaptation [McKinley2004] ■ Internal adaptation vs. external adaptation [Salehie2009]
[Schäfer2007] [Musliner1999]
Motivation:
Reconfiguration in Cyber-Physical Systems
SLIDE 8
Points to Discuss
■ (I) cover dynamic behavior via explicit modeled and coexisting feedback loops ■ (II) reduce complexity and enable interaction via abstraction using runtime models following the model driven engineering approach ■ (III) consider specific domains and nonfunctional properties ■ (IV) support concurrent and distributed interactions of subsystems
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Reconfiguration in Cyber-Physical Systems (Adaptation)
SLIDE 9
Points to Discuss: Cyber-Physical Systems Laboratory
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SLIDE 10
Feedback Loop
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Adaptable Cyber-Physical System
SLIDE 11
Adaptation Engine
Feedback Loop
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Adaptable Cyber-Physical System Monitor Analyze Plan Execute Knowledge
SLIDE 12
Adaptation Engine
Feedback Loop with Runtime Models
■ External adaptation approach as proposed in [Salehie2009] ■ Feedback loop with four activities: □ Monitor-Analyse-Plan- Execute Knowledge (MAPE-K) [IBMKephart2003] ■ Runtime models as on-line representation of the running system [Vogel2011] □ Reflection models □ Evaluation models □ Change models □ Execution models
Sebastian Wätzoldt | Reconfiguration in Cyber-Physical Systems | HPI Symposium @ SAP
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Adaptable Cyber-Physical System Monitor Analyze Plan Execute Knowledge
SLIDE 13 Multiple Feedback Loops
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Adaptable Cyber-Physical System Self- healing
M A P E
Self-
M A P E
Separation of loops: ■ Different concerns [Frey2012] □ Self-healing □ Self-optimizing □ Hard real-time adaptation
adaptation ■ Local vs. global adaptation
[Gueye2012]
SLIDE 14 Multiple Feedback Loops
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Adaptable Cyber-Physical System
M A P E M A P E
Problems: ■ Inter-loop communication ■ Model exchange ■ Concurrency coordination ■ Contradicting model manipulation Separation of loops: ■ Different concerns [Frey2012] □ Self-healing □ Self-optimizing □ Hard real-time adaptation
adaptation ■ Local vs. global adaptation
[Gueye2012]
Self- healing Self-
SLIDE 15 Multiple Layered Feedback Loops
■ Handle different problems on different level of abstraction e.g. inspired by adaptive control theory
[Kokar1999]
■ Hierarchical control architectures
[IBMKephart2003]
■ Proposed reference architecture for self-managed software systems
[Kramer2007]
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Adaptable Cyber-Physical System Hard Real-Time Adaptation
M A P E
Self- healing
M A P E
Self-
M A P E …
SLIDE 16 Distributed Multiple Layered Feedback Loops
■ Complex CPS with several independent, heterogeneous subsystems □ Autonomous robots in a warehouse □ Distributed traffic management ■ Runtime models □ Basic communication concept □ Exchange of information possible □ Learn, adapt on new situations via model driven techniques
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Adaptable CPS HRT Self-
M A P E …
Adaptable CPS
…
Self- H. HRT
SLIDE 17
Example: Cyber-Physical Systems Laboratory
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SLIDE 18
Example
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Adaptable Cyber-Physical System
SLIDE 19
Example: Failure Detection and Repair
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Adaptable Cyber-Physical System Failure Detection + Repair
M A P E
SLIDE 20
Example: Failure Detection and Repair Monitor
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Failure Detection + Repair
M A P E
Monitor Knowledge Adaptable Cyber-Physical System
<<Component>> Navigation Logic <<Sensor>> Obstacle Detection <<Sensor>> Localization <<Actuator>> Wheel
SLIDE 21
<<Component>> Navigation Logic <<Sensor>> Obstacle Detection <<Sensor>> Localization <<Actuator>> Wheel
Example: Failure Detection and Repair Monitor
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M A P E
Monitor Knowledge Adaptable Cyber-Physical System Failure Detection + Repair
SLIDE 22
Example: Failure Detection and Repair Analyze
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M A P E
Knowledge Rules Analyze Adaptable Cyber-Physical System
<<Component>> Navigation Logic <<Sensor>> Obstacle Detection <<Sensor>> Localization <<Actuator>> Wheel
Failure Detection + Repair
SLIDE 23
Example: Failure Detection and Repair Analyze
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M A P E
Knowledge Analyze Rules Adaptable Cyber-Physical System
<<Component>> Navigation Logic <<Sensor>> Obstacle Detection <<Sensor>> Localization <<Actuator>> Wheel
replace Failure Detection + Repair
SLIDE 24
Example: Failure Detection and Repair Plan
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M A P E
Knowledge Plan Adaptable Cyber-Physical System
<<Component>> Navigation Logic <<Sensor>> Obstacle Detection <<Sensor>> Localization <<Actuator>> Wheel
replace Failure Detection + Repair
SLIDE 25
Example: Failure Detection and Repair Plan
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M A P E
Knowledge Plan Component repository
1) Remove old component 2) Load backup component 3) Connect backup component
Adaptable Cyber-Physical System
<<Component>> Navigation Logic <<Sensor>> Obstacle Detection <<Sensor>> Localization <<Actuator>> Wheel
replace
<<Sensor>> BACKUP Obstacle Detection
Failure Detection + Repair
SLIDE 26
Example: Failure Detection and Repair Execute
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M A P E
Knowledge Execute Adaptable Cyber-Physical System
1) Remove old component 2) Load backup component 3) Connect backup component <<Component>> Navigation Logic <<Sensor>> Obstacle Detection <<Sensor>> Localization <<Actuator>> Wheel
replace
<<Sensor>> BACKUP Obstacle Detection
Failure Detection + Repair
SLIDE 27
Summary: Cyber-Physical Systems Laboratory
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SLIDE 28 Sebastian Wätzoldt | Reconfiguration in Cyber-Physical Systems | HPI Symposium @ SAP
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Summary:
Reconfiguration in Cyber-Physical Systems
[acatech2011]
Adapt cyber-physical systems at runtime: A research challenge!
SLIDE 29 References
■ Erik Coelingh, Stefan Solyom. All Aboard the Robotic Road Train. IEEE Spectrum, November,2012. http://spectrum.ieee.org/green-tech/advanced-cars/all-aboard-the-robotic-road-train ■ Hyun Jung La, Soo Dong Kim. A Service-Based Approach to Designing Cyber Physical
- Systems. Computer and Information Science, ACIS International Conference on, pp. 895-900,
2010 IEEE/ACIS 9th International Conference on Computer and Information Science, 2010 ■ Edward A. Lee. Cyber Physical Systems: Design Challenges. Technical report, EECS Department, University of California, Berkeley, UCB/EECS-2008-8, Jan, 2008. ■ Wilhelm Schäfer and Heike Wehrheim. 2007. The Challenges of Building Advanced Mechatronic Systems. In 2007 Future of Software Engineering (FOSE '07). IEEE Computer Society, Washington, DC, USA, 72-84. DOI=10.1109/FOSE.2007.28 http://dx.doi.org/10.1109/FOSE.2007.28 ■ David J. Musliner, Robert P. Goldman, Michael J. Pelican and Kurt D. Krebsbach. Self-Adaptive Software for Hard Real-Time Environments. In IEEE Intelligent Systems, Vol. 14(4), July 1999. ■ Philip McKinley, Seyed Masoud Sadjadi, Eric P. Kasten and Betty H. Cheng. Composing Adaptive
- Software. In IEEE Computer, Vol. 37(7):56-64, July 2004.
■ Mazeiar Salehie and Ladan Tahvildari. Self-adaptive software: Landscape and research
- challenges. In ACM Trans. Auton. Adapt. Syst., Vol. 4(2):1--42, ACM, New York, USA , 2009.
■ Thomas Vogel, Andreas Seibel and Holger Giese. The Role of Models and Megamodels at
- Runtime. In Models in Software Engineering, Workshops and Symposia at MODELS 2010, Oslo,
Norway, October 3-8, 2010, Reports and Revised Selected Papers, Vol. 6627:224-238 of Lecture Notes in Computer Science (LNCS), Springer-Verlag, May 2011.
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SLIDE 30 References
■ Jeffrey O. Kephart and David Chess. The Vision of Autonomic Computing. In Computer, Vol. 36(1):41--50, IEEE Computer Society Press, Los Alamitos, CA, USA, January 2003. ■ Sylvain Frey, Ada Diaconescu and Isabelle M. Demeure. Architectural Integration Patterns for Autonomic Management Systems. In Proceedings of the 9th IEEE International Conference and Workshops on the Engineering of Autonomic and Autonomous Systems (EASe 2012), 2012. ■ Soguy Mak Karé Gueye, Noel De Palma and Eric Rutten. Coordinating Energy-aware Administration Loops Using Discrete Control. In Proceedings of the 8th International Conference on Autonomic and Autonomous Systems (ICAS 2012), Pages 99--106, IARIA, 2012. ■ Mieczyslaw M. Kokar, Kenneth Baclawski and Yönet A. Eracar. Control Theory-Based Foundations of Self-Controlling Software. In Intelligent Systems and their Applications, Vol. 14(3):37-45, 1999. ■ Jeff Kramer and Jeff Magee. Self-Managed Systems: an Architectural Challenge. In FOSE '07: 2007 Future of Software Engineering, Pages 259--268, IEEE Computer Society, Washington, DC, USA , 2007. ■ acatech, ed. (2011). Cyber-Physical Systems: Driving Force for Innovation in Mobility, Health, Energy and Production (acatech POSITION PAPER). acatech -- National Academy of Science and Engineering , Munich, Germany, 2011. ■ Geisberger, E. and Broy, M. agendaCPS: Integrierte Forschungsagenda Cyber-Physical
- Systems. acatech STUDIE, Springer, 2012.
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