Course Description
Almost all modern control systems, such as those found in
automobiles, aircraft, robots, or industrial processing plants, are
implemented on digital platforms, and many of them are
embedded systems.
Unfortunately, the well-rounded theory of digital
control has not kept pace with the multitude of complex system integration
issues raised by this trend. Many of the aspects that
could formerly be qualified by the control engineer as
"implementation issues" play today a crucial role in
determining the viability of the overall
system, with respect to performance,
cost, reliability, maintainability, etc.
Control system design now involves a good understanding not
only of the physical process of interest
but also of the
technological aspects such as overall system architecture,
number of computing units, communication networks and
protocols between the units, task scheduling in real-time
operating systems, etc. All these elements can impact
significantly the performance of the closed-loop system.
The result is a convergence between
the fields of control, communication, embedded system design
and software verification, which is still in its infancy.
The goal of this course is to introduce the students to some
important aspects of the design of Networked and Embedded
Control Systems, and to bring them up-to-date on this
currently very active research field. A tentative list of topics includes:
fundamentals of digital control; quantization effects; imperfect sampling; control
under computation and communication constraints, including
real-time scheduling; fundamentals of hybrid systems;
system verification: model checking and deductive methods; decentralized control;
Model-Driven Engineering.
Course Philosophy, Prerequisites, and Grading
This is a topics course that I plan to run partly as a
formal course and partly as a seminar.
The content might be adjusted
based on the interest of the participants.
Emphasis is on the theory during the lectures, but the students
are strongly encouraged to explore more practical issues
(e.g. software, implementation experiments on physical platforms) during
the project.
In contrast to other courses offered at Penn on the broader topic of
Cyber-Physical Systems (CPS), this course has a strong
emphasis on control systems, and previous exposure to
control theory is a prerequisite.
For example, students should have taken a linear systems course and know about Lyapunov
analysis.
It would be good to have some previous exposure to
stochastic models and Kalman filtering for certain parts of
the course.
Basic knowledge of computer science concepts (automata
theory, logic) is a plus but not a
strict prerequisite.
It is likely that there will be some overlap with
the
hybrid systems course offered occasionally by George
Pappas, but I expect a significant amount of new material.
We might revisit topics you have already seen if
you have taken CIS 540 (Principles of Embedded Computation)
or CIS 541 (CPS), but again in the context of control systems.
Grading: class
presentation (40%), project (40-50%), participation (10%),
homework (TBD) (0-10%).
The problem sets are mainly used to make sure you are not
lost.
Students will also be responsible for teaching a lecture, on
a topic determined with the instructor,
which includes the preparation of lecture notes (this will
be adjusted based on the number of participants).
The project constitutes a significant part of the course, and can be
done alone or in pairs (recommended). It can be either: 1)
the design of a digital control system, with the goal of
being as realistic as possible, i.e. including as many
implementation effects in your simulations and design as
possible, possibly physically implementing your controller it if you have access to
hardware (physical implementation is not required; note that the course does not discuss embedded
systems programming); or 2) a serious attempt at a novel contribution to the
field of NECS. No literature review is accepted for the
project, this being the object of the class presentation
already.
Auditors:
Auditors are welcome in the class. It is likely that student
auditors will be required to give a class presentation as well.
(very tentative schedule, with dates subject to change:
please revisit regularly during the term.
Also, the notes are pretty rough and not proofread, they
should just guide your study).
References for the notes.
| Date |
Topic |
Reading + Some References |
Assignments |
| W. Jan. 12 |
Introduction |
slides |
|
| M. Jan. 17 |
MLK Day |
|
|
| W. Jan. 19 |
Modeling of Continuous and Discrete Signals and Systems |
Notes.
Transition
Systems |
|
| M. Jan. 24 |
Modeling of Continuous and Discrete Signals and Systems |
Notes.
Hybrid Systems
I,
II |
|
| W. Jan. 26 |
Sampling and Sampled-Data Systems |
Notes,
[AW96], [CF96], [GYAC10], [A70] |
|
| M. Jan. 31 |
Sampling and Sampled-Data Systems |
Notes,
[AW96], [CF96], [GYAC10], [A70] |
|
| W. Feb. 2 |
More about step-invariant discretization, issues with DT control |
Notes
I,
Notes
II.
[AW96], [CF96]
| |
| M. Feb. 7 |
Discretization of CT controllers, bilinear
transformation, setup for optimal discretization |
[CF96] |
|
| W. Feb. 9 |
Stochastic noise, H2 norm interpretation, Sampling stochastic
differential Equations,
Class discussion about [LSM10] |
Misc |
Presentation Proposal Due |
| M. Feb. 14 |
NECS: implementation issues |
Slides.
RT
Scheduling I,
II
|
|
| W. Feb. 16 |
NECS: implementation issues, modeling discussion |
|
| M. Feb. 21 |
NECS: discretization at sampling times, Lyapunov
analysis for stability |
[ZBP01], [CHW+10] |
|
| W. Feb. 23 |
NECS: Lyapunov techniques |
[ZBP01], [CHW+10] |
|
| M. Feb. 28 |
Class canceled (traveling) |
|
|
| W. March 2 |
Time-Triggered Implementation of Controllers (Truong
Nghiem) |
|
Project Proposal Due |
| March 5-13 |
Spring Term Break |
|
|
| M. March 14 |
Wrap-up Lyapunov techniques and LMIs |
|
|
| W. March 16 |
Kalman filtering with Intermittent Observations (Yash) |
[SSF+04] |
|
| M. March 21 |
Class canceled (traveling) |
|
|
| W. March 23 |
Class canceled (traveling) |
|
|
| M. March 28 |
Control over Wireless Networks (Konstantinos) |
|
|
| W. March 30 |
Control and Real-Time Scheduling (Philip) |
|
|
| M. April 4 |
Quantization Effects (Chris) |
|
|
| W. April 6 |
Review of input-output analysis: small-gain |
|
|
| M. April 11 |
(CPS Week) Switched Systems (Zack) |
|
|
| W. April 13 |
(CPS Week) Lifting and small-gain applied to NECS |
[M07] |
|
| M. April 18 |
AADL (Oleg Sokolsky) |
|
|
| W. April 20 |
Event-Triggered Sampling in Control (Miroslav) |
|
|
| M. April 25 |
Passivity and wave-variables for NECS |
|
Final Project Report due |
Examples of Topics for Additional Student Lectures
Distributed control (decentralized fixed modes, quadratic
invariance, ...)
Distributed Estimation (distributed LMS, RLS, and Kalman
filtering, ...)
Switched Systems
Model Predictive Control with Logic Constraints
Barrier Certificates and Sum-of-Squares
Event-based sampling for control
References
(will be updated during the term)
Textbooks and Tutorials
[GPW97] G. F. Franklin, J. D. Powell and M. L. Workman, "Digital Control of Dynamic Systems",
3rd edition, Prentice Hall, 1997.
[AW96] K. J. Astrom and B. Wittenmark, "Computer-Controlled Systems: Theory and Design",
3rd edition, Prentice Hall, 1996.
[A70] K. J. Astrom, "Introduction to Stochastic Control
Theory", Academic Press, 1970 (republished by Dover in
2006).
[CF96] T. Chen and B. A. Francis, "Optimal Sampled-Data Control Systems",
Springer, 1996.
[FG96] A. Feuer and G. C. Goodwin, "Sampling in Digital Signal Processing and Control",
Birkhäuser, 1996.
[WAA02] B. Wittenmark, K. J. Astrom and K.-E. Arzen,
"Computer Control: An Overview",
IFAC Professional Brief, 2002.
[Wes00] T. Wescott,
"
PID
Without a PhD"
Embedded Systems Programming, October 2000.
[Liu00] J. W. S. Liu, "Real-Time Systems",
Prentice Hall, 2000.
[CL08] C. G. Cassandras and S. Lafortune, "Introduction to
Discrete Event Systems", 2nd edition,
Springer, 2008.
[Tab09] P. Tabuada, "
Verification
and Control of Hybrid Systems: A Symbolic Approach",
Springer, 2009.
[Pla10] A. Platzer, "
Logical Analysis of Hybrid Systems",
Springer, 2010.
[BK08] C. Baier and J.-P. Katoen, "Principles of Model Checking",
The MIT Press, 2008.
[Sch10] K. Schneider, "Verification of Reactive Systems: Formal Methods and Algorithms",
Springer, 2003.
Research Monographs and Technical Papers
[Wil78] A. S. Willsky, "Relationships Between Digital Signal
Processing and Control and Estimation Theory", Proceedings of
the IEEE, vol. 66, no. 9, pp. 996-1017, September 1978.
[GYAC10] G. C. Goodwin, J. I. Yuz, J. C. Agüero, M. Cea,
"
Sampling and Sampled-Data Models", Proceedings of the
American Control Conference, pp. 1-20, 2010.
[NCS]
Networked Control
Systems Repository
[Al+05] R. Alur, K.-E. Arzen, J. Baillieul, T.A. Henzinger,
D. Hristu-Varsakelis, W. S. Levine, Editors, "Handbook of Networked and Embedded Control Systems", Birkhauser, 2005.
[ZBP01] W. Zhang and M.S. Branicky and S.M. Philips, "
Stability
of Networked Control Systems", IEEE Control Systems
Magazine, vol. 21(1), pp. 84-99, Feb 2001.
[CHW+10] M.B.G. Cloosterman, L. Hetel, N. van de Wouw,
W.P.M.H. Heemels, J. Daafouz and H. Nijmeijer, "
Controller
Synthesis for Networked Control Systems",
Automatica , Volume 46, pp. 1584-1594, 2010.
[LSM10] J. Lavaei, S. Somayeh and R. M. Murray, "
Delay-Based
Controller Design for Continuous-Time and Hybrid
Applications", Caltech Technical Report, 2010.
[SSF+04] B. Sinopoli, L. Schenato, M. Franceschetti,
K. Poola, M.I. Jordan, S.S. Sastry, "
Kalman
Filtering with Intermittent Observations", IEEE
Transactions on Automatic Control, Vol. 49 (9),
pp. 1453-1464, Sept. 2004.
[M07] L. Mirkin, "
Some Remarks on the Use of Time-Varying
Delay to Model Sample-and-Hold Circuits", IEEE
Transactions on Automatic Control, Vol. 52 (6), pp. 1109-1112, June 2007.
[DO178]
DO-178B
and the future
DO-178C: Software Considerations in Airborne Systems and Equipment Certification
[ARINC653]
ARINC
653: Avionics Application Standard Software Interface
[AFDS]
Avionics
Full-Duplex Switched Ethernet (AFDX)
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