Apresentação realizada no Simpósio Brasileiro de Engenharia de Sistemas Computacionais - SBESC 2014, na cidade de Manaus -AM.

1. Assessing the Use of Continuous-Time and
Timed-Triggered Models for Designing
Cyber-Physical Systems
F. S. Goncalves, L. B. Becker
Department of Automation and Systems - DAS
Federal University of Santa Catarina - Brazil
IV Brazilian Symposium on Computing
Systems Engineering - SBESC
November 6, 2014

2. Motivation UAV TT Model CT Model Analyze Conclusion Assessing the Use of CT and TT Models for Designing CPS
Summary
Motivation
UAV Characteristics
Time-Triggered Model
Continuous-Time Model
Comparative Analyzes
Conclusion
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3. Motivation UAV TT Model CT Model Analyze Conclusion Assessing the Use of CT and TT Models for Designing CPS
Summary
Motivation
UAV Characteristics
Time-Triggered Model
Continuous-Time Model
Comparative Analyzes
Conclusion
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4. Motivation UAV TT Model CT Model Analyze Conclusion Assessing the Use of CT and TT Models for Designing CPS
Cyber Physical System - CPS
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5. Motivation UAV TT Model CT Model Analyze Conclusion Assessing the Use of CT and TT Models for Designing CPS
Cyber Physical System - CPS
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6. Motivation UAV TT Model CT Model Analyze Conclusion Assessing the Use of CT and TT Models for Designing CPS
ProVANT Project
Research testbed for Cyber-
physical systems:
) Modeling embedded critical sys-
tems;
) Wireless communication;
) Control systems;
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7. Motivation UAV TT Model CT Model Analyze Conclusion Assessing the Use of CT and TT Models for Designing CPS
Paper Goals
Present two MoCs, CT and the TT, for designing the stability control
system of an UAV, which is an example of a typical CPS;
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8. Motivation UAV TT Model CT Model Analyze Conclusion Assessing the Use of CT and TT Models for Designing CPS
Paper Goals
Present two MoCs, CT and the TT, for designing the stability control
system of an UAV, which is an example of a typical CPS;
Address the facilities and diculties on mapping the high-level mod-
els representing these two MoCs to a typical execution platform.
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9. Motivation UAV TT Model CT Model Analyze Conclusion Assessing the Use of CT and TT Models for Designing CPS
Summary
Motivation
UAV Characteristics
Time-Triggered Model
Continuous-Time Model
Comparative Analyzes
Conclusion
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10. Motivation UAV TT Model CT Model Analyze Conclusion Assessing the Use of CT and TT Models for Designing CPS
UAV Characteristics
Vertical Take-O and Landing
(VTOL) con

11. guration;
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12. Motivation UAV TT Model CT Model Analyze Conclusion Assessing the Use of CT and TT Models for Designing CPS
UAV Characteristics
Vertical Take-O and Landing
(VTOL) con

13. guration;
Physical System:
) Rotors can tilt longitudinally;
) Fixed tilt angle laterally;
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14. Motivation UAV TT Model CT Model Analyze Conclusion Assessing the Use of CT and TT Models for Designing CPS
UAV Characteristics
Vertical Take-O and Landing
(VTOL) con

15. guration;
Physical System:
) Rotors can tilt longitudinally;
) Fixed tilt angle laterally;
System's characteristics:
) Underactuated mechanical
system;
) Highly nonlinear and time
varing behavior;
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16. Motivation UAV TT Model CT Model Analyze Conclusion Assessing the Use of CT and TT Models for Designing CPS
Mathematical Representation
Control equations in relation to the control inputs:
fL =
1
2
r
h
+
l
2
+
Fzb
l
2
;
fR =
1
2
r
h
l
2
+
Fzb +
l
2
:
(1)
L = arctan
h +
l
Fzb
l
!
;
R = arctan
h
l
Fzb +
l
!
:
(2)
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17. Motivation UAV TT Model CT Model Analyze Conclusion Assessing the Use of CT and TT Models for Designing CPS
Hardware Structure
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18. Motivation UAV TT Model CT Model Analyze Conclusion Assessing the Use of CT and TT Models for Designing CPS
Summary
Motivation
UAV Characteristics
Time-Triggered Model
Continuous-Time Model
Comparative Analyzes
Conclusion
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19. Motivation UAV TT Model CT Model Analyze Conclusion Assessing the Use of CT and TT Models for Designing CPS
Time-Triggerred Model Characteristics
Composed by:
) RT Entity (control);
) Two Transducers (estimation and actuation);
) Communication System (communication);
) Three Interfaces (intEstimation, intActuation and intControl);
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20. Motivation UAV TT Model CT Model Analyze Conclusion Assessing the Use of CT and TT Models for Designing CPS
Time-Triggered Model
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21. Motivation UAV TT Model CT Model Analyze Conclusion Assessing the Use of CT and TT Models for Designing CPS
Summary
Motivation
UAV Characteristics
Time-Triggered Model
Continuous-Time Model
Comparative Analyzes
Conclusion
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22. Motivation UAV TT Model CT Model Analyze Conclusion Assessing the Use of CT and TT Models for Designing CPS
Simulink Model
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23. Motivation UAV TT Model CT Model Analyze Conclusion Assessing the Use of CT and TT Models for Designing CPS
Continuous-Time Model Characteristcs
Composed by a set of threads:
) Control thread;
) Communication thread;
) Main thread;
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24. Motivation UAV TT Model CT Model Analyze Conclusion Assessing the Use of CT and TT Models for Designing CPS
Continuous-Time Model
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25. Motivation UAV TT Model CT Model Analyze Conclusion Assessing the Use of CT and TT Models for Designing CPS
Summary
Motivation
UAV Characteristics
Time-Triggered Model
Continuous-Time Model
Comparative Analyzes
Conclusion
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26. Motivation UAV TT Model CT Model Analyze Conclusion Assessing the Use of CT and TT Models for Designing CPS
Evaluation Criteria
Maintainability: describe the easiness to make modi

27. cations in the
model;
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28. Motivation UAV TT Model CT Model Analyze Conclusion Assessing the Use of CT and TT Models for Designing CPS
Evaluation Criteria
Maintainability: describe the easiness to make modi

29. cations in the
model;
Modularity / Hierarchy: analyze the capability of split the system
into independent modules;
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30. Motivation UAV TT Model CT Model Analyze Conclusion Assessing the Use of CT and TT Models for Designing CPS
Evaluation Criteria
Maintainability: describe the easiness to make modi

31. cations in the
model;
Modularity / Hierarchy: analyze the capability of split the system
into independent modules;
Expressiveness: that use of modeling language primitives to de-
scribe the speci

32. cation;
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33. Motivation UAV TT Model CT Model Analyze Conclusion Assessing the Use of CT and TT Models for Designing CPS
Evaluation Criteria
Simulation: verify if the speci

34. cation can be used to validate the
implementation;
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35. Motivation UAV TT Model CT Model Analyze Conclusion Assessing the Use of CT and TT Models for Designing CPS
Evaluation Criteria
Simulation: verify if the speci

36. cation can be used to validate the
implementation;
Veri

37. cation: capability of demonstrating formally that the system
meets the requirements;
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38. Motivation UAV TT Model CT Model Analyze Conclusion Assessing the Use of CT and TT Models for Designing CPS
Evaluation Criteria
Simulation: verify if the speci

39. cation can be used to validate the
implementation;
Veri

40. cation: capability of demonstrating formally that the system
meets the requirements;
Implementability: evaluating how the speci

41. cation can be easily
re

42. ned or translated into an implementation.
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43. Motivation UAV TT Model CT Model Analyze Conclusion Assessing the Use of CT and TT Models for Designing CPS
Comparison Results
Evaluation Criteria TT Model CT Model
1 - Maintainability
2 - Modularity / Hierarchy
3 - Expressiveness 1250 1184
4 - Simulation
5 - Veri

44. cation
6 - Implementability
** Strong / * Adequate / 0 weak
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45. Motivation UAV TT Model CT Model Analyze Conclusion Assessing the Use of CT and TT Models for Designing CPS
Comparison Results
Evaluation Criteria TT Model CT Model
1 - Maintainability
2 - Modularity / Hierarchy
3 - Expressiveness 1250 1184
4 - Simulation
5 - Veri

46. cation
6 - Implementability
** Strong / * Adequate / 0 weak
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47. Motivation UAV TT Model CT Model Analyze Conclusion Assessing the Use of CT and TT Models for Designing CPS
Comparison Results
Evaluation Criteria TT Model CT Model
1 - Maintainability
2 - Modularity / Hierarchy
3 - Expressiveness 1250 1184
4 - Simulation
5 - Veri

48. cation
6 - Implementability
** Strong / * Adequate / 0 weak
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49. Motivation UAV TT Model CT Model Analyze Conclusion Assessing the Use of CT and TT Models for Designing CPS
Summary
Motivation
UAV Characteristics
Time-Triggered Model
Continuous-Time Model
Comparative Analyzes
Conclusion
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50. Motivation UAV TT Model CT Model Analyze Conclusion Assessing the Use of CT and TT Models for Designing CPS
Conclusions
Both models meet the requirements and support the UAV system;
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51. Motivation UAV TT Model CT Model Analyze Conclusion Assessing the Use of CT and TT Models for Designing CPS
Conclusions
Both models meet the requirements and support the UAV system;
Implementing the models in the embedded platform is not a trivial
task;
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52. Motivation UAV TT Model CT Model Analyze Conclusion Assessing the Use of CT and TT Models for Designing CPS
Conclusions
Both models meet the requirements and support the UAV system;
Implementing the models in the embedded platform is not a trivial
task;
) Implementation of the TT Model is more straightforward;
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53. Motivation UAV TT Model CT Model Analyze Conclusion Assessing the Use of CT and TT Models for Designing CPS
Conclusions
Both models meet the requirements and support the UAV system;
Implementing the models in the embedded platform is not a trivial
task;
) Implementation of the TT Model is more straightforward;
) Implementation of the CT Model needs more expertise of the
engineers.
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54. Assessing the Use of Continuous-Time and
Timed-Triggered Models for Designing
Cyber-Physical Systems
F. S. Goncalves, L. B. Becker
Department of Automation and Systems - DAS
Federal University of Santa Catarina - Brazil
IV Brazilian Symposium on Computing
Systems Engineering - SBESC
November 6, 2014