Welcome to
TE 303
Control Systems!
Fall 2012
Wednesday, Thursday
Section A: 11.30-13.00 (C1, C2)
Section B: 08:30-10.00 (C2, C1)
Basic Information
• Instructor Contact Information
– Muhammad Ali Riaz, 2134 Coover Hall
– ali.riaz@uettaxila.edu.pk; 9047-773
– Office Hours: Monday 11:30-13:00 (2k10A), Monday
10:00-11:30 (2k10B)
– Or any other time convenient to you
– Please include “TE 303” in the subject line in all email communications
to avoid auto-deleting or junk-filtering
Textbook
• Modern Control Engineering
Fifth Edition
Katsuhiko Ogata
• Reference books shall be provided later
Final Grade Weighting Schedule
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Homework average: 10%
Midterm exam1: 20%
Final exam: 40%
Quizzes: 10%
Laboratory: 20%
Grading Scale: Depends on class distribution
Catalog Description
• Classification of open and closed loop control,
advantages and disadvantages
• Effects of feedback, examples including
servomechanism
• System model and characterization, Block
diagrams and canonical form
• Examples of control systems from Telecom
applications such as satellite
Catalog Description
• Signal flow graphs and Laplace Transforms,
Transfer function
• Poles and zeros
• Time domain analysis
• Steady state error using static error coefficient
method
• Dynamic error constant method
• Feedback characteristics of control systems
• Sensitivity of control systems
Catalog Description
• Basic action of Controllers (Proportional,
Integral, PI and PID controllers)
• Stability assessment (Routh, Bode, Nyquist,
Nicholes chart)
• Compensation and compensator design
• State space Analysis
Prerequisite by topics
• Knowledge and proficiency in Matlab
• Concept and solution of linear ordinary
differential equations
• Laplace transform and its applications
• Poles, zeros, transfer functions, frequency
response, Bode plots
• Vectors and matrices
• Complex numbers
OBJECTIVES
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On completion of TE 303, the student will be able to do the following either by hand or with
the help of computation tools such as Matlab:
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Define the basic terminologies used in controls systems
Explain advantages and drawbacks of open-loop and closed loop control systems
Obtain models of simple dynamic systems in ordinary differential equation, transfer function, state
space, or block diagram form
Obtain overall transfer function of a system using either block diagram algebra, or signal flow graphs,
or Matlab tools.
Compute and present in graphical form the output response of control systems to typical test input
signals
Explain the relationship between system output response and transfer function characteristics or
pole/zero locations
Determine the stability of a closed-loop control systems using the Routh-Hurwitz criteria
Analyze the closed loop stability and performance of control systems based on open-loop transfer
functions using the Root Locus technique
Design PID or lead-lag compensator to improve the closed loop system stability and performance
using the Root Locus technique
Analyze the closed loop stability and performance of control systems based on open-loop transfer
functions using the frequency response techniques
Design PID or lead-lag compensator to improve the closed loop system stability and performance
using the frequency response techniques
Topics Covered
• Review of signal systems concepts and techniques as applied to control
system
• Block diagrams and signal flow graphs
• Modeling of control systems using ode, block diagrams, and transfer
functions
• Modeling and analysis of control systems using state space methods
• Analysis of dynamic response of control systems, including transient
response, steady state response, and tracking performance.
• Closed-loop stability analysis using the Routh-Hurwitz criteria
• Stability and performance analysis using the Root Locus techniques
• Control system design using the Root Locus techniques
• Stability and performance analysis using the frequency response
techniques
• Control system design using the frequency response techniques
• If there is time, Control system design using the state space techniques
Student behavior expectations
• Full attendance expected, except with prior-notified
excuses
• On-time arrival
• Active participation
– Ask questions
– Answer questions from instructor or students
• Be cordial and considerate to students
• Help each other in reviewing notes, HW, Matlab
• Promptly report/share problems/issues, including
typos on slides, or misspoken words from instructor
Prohibited behaviors
• Any foul language or gestures
• Comments to other students that are
discriminatory in any form
• Any harassments as defined by the university
• Academic dishonesty
• No alcohol, drugs, or any other illegal /
improper substances
– Snacks/drinks OK as long as you don’t spill and
clean up
Accommodation/Assistance
• Please let me know if you
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Have any special needs
Have disability in any form
Have any medical/mental/emergency conditions
Have field trip / interview
Have special requests
Want me to adjust lecture contents/pace
• Can also consult me if you
– Would like to seek advice on any professional or personal
issues
– Would like to have certain confidential discussions
Collaboration And Helping Each
Other
• For tasks intended for group work, you are expected to find a
partner and share the tasks among the group members. In a
group project, effective teamwork is critical to maximize the
productivity of the whole group. In the submitted work,
identify components and indicate percentage contribution by
each member to each component.
• For tasks not intended for group work, individual submission
is required. In this case, you are encouraged to discuss among
your friends on how to attack problems. However, you should
write your own solution. Copying other people’s work is
strictly prohibited.
Academic dishonesty
• Cheating is a very serious offense. It will be dealt with in the
most severe manner allowable under University regulations. If
caught cheating, you can expect a failing grade and initiation
of a cheating case in the University system.
• Basically, it’s an insult to the instructor, the department and
major program, and most importantly, to the person doing the
cheating. Just don't.
• If in doubt about what might constitute cheating, send e-mail
to your instructor describing the situation. If you notice
anyone cheating, please report it to the instructor. Do not
deal with it yourself.
Discrimination
• Federal laws as well as UET, Taxila policies prohibit any form of
discrimination on the basis of race, color, age, religion,
national origin, gender, marital status, or disability. Language
or gestures of discriminatory nature will not be tolerated.
Severe cases will be reported to appropriate offices.
• Let us make every effort to work together and create a
positive, collegial, caring, and all-supportive learning
environment in our classroom, laboratory, and instructor
office.
Disability accommodation
• Individuals with physical or mental impairments who
are otherwise qualified to perform their work or
pursue their studies may request reasonable
accommodations to enable them to work or continue
their studies.
• If you believe you have learning disability, you must
contact me right away.
Control Systems History
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Watt, steam engine speed control governor
Black, feedback amplifiers
Minorsky, ship steering stability
Nyquist, closed-loop stability from open-loop
Hazen, Servomechanisms
Bode, Bode plot, and BP based control design
Evans, root locus plot, RL based design
Kalman, state space, controllability, Kalman filter
Anderson…, linear optimal control
Figure 1-1 Speed control system.
Control Systems History
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Bellman, dynamic programming
Pontryagin, maximum principle
Lyapunov, nonlinear systems
Sastry…, adaptive control
Arimoto, learning control
Doyle…, robust control
Byrnes/Isidori, nonlinear regulation
Devasia/Chen/Paden, stable inversion
Kokotovic, backstepping
Control System Terminology
• Input - Excitation applied to a control system
from an external source.
• Output - The response obtained from a system
• Feedback - The output of a system that is
returned to modify the input.
• Error - The difference between the reference
input and the output.
Negative Feedback Control System
+
CONTROLLER
-
FEEDBACK
ELEMENT
+
+
CONTROLLED
DEVICE
Negative Feedback Control System
+
CONTROLLER
-
FEEDBACK
ELEMENT
+
+
CONTROLLED
DEVICE
Types of Control Systems
ø Open-Loop
– Simple control system which performs its function
with-out concerns for initial conditions or external
inputs.
– Must be closely monitored.
ø Closed-Loop (feedback)
– Uses the output of the process to modify the
process to produce the desired result.
– Continually adjusts the process.
Advantages of a Closed-Loop
Feedback System
ø Increased Accuracy
– Increased ability to reproduce output with varied input.
ø Reduced Sensitivity to Disturbance
– By self correcting it minimizes effects of system changes.
ø Smoothing and Filtering
– System induced noise and distortion are reduced.
ø Increased Bandwidth
– Produces sat. response to increased range of input
changes.
Major Types of Feedback Used
ø Position Feedback
– Used when the output is a linear distance or
angular measurement.
ø Rate & Acceleration Feedback
– Feeds back rate of motion or rate of change of
motion (acceleration)
– Motion smoothing
– Uses a electrical/mechanical device call an
accelerometer
Fire Control Problem
Present
Position
Ship’s
Heading
Bearing
Change
Future
Position
Range Change
A German anti-aircraft 88
mm gun with its fire-control
computer from World War II.
Displayed in the Canadian
War Museum.
Fire Control Problem
• Input
– Target data
– Own ship data
• Computations
– Relative motion procedure
– Exterior ballistics procedure
Fire Control Problem
• Solutions
– Weapons time of flight
– Bearing rate
– Line of Sight(LOS): The line between the target and the firing
platform
– Speed across LOS
– Future target position
– Launch angles
• Launch azimuth
• Launch elevation
– Weapon positioning orders
• The above determines weapon trajectory: The line the weapon must
travel on to intercept the target.
The Iterative Process to the
Fire Control Solution
Step 1
Step 2
Step 3
Last Step
A 3-Dimensional Problem
Line of Sight
Target
Elevation
Gun
Elevation
Horizontal Reference Plane
Solving the Fire Control Problem
Continuously Measure
Present Target Position
Stabilize Measured
Quantities
Compute Relative
Target Velocity
Environmental Inputs
Weapons Positioning orders
Unstabilized
Launch
Angles
Ballistic
Calculations
Launch Angles
(Stabilized)
Future
Target
Position
Time of
Flight
Relative
Motion
Calculations
Prediction Procedure
Temperature control system.
Block diagram of an engineering organizational system.
Idle-speed control system.
Conceptual method of efficient water extraction
using solar power.
Important components of the sun-tracking
control system.
Antenna azimuth position control system:
a. system concept;
b. detailed layout;
c. schematic;
d. functional block diagram
a. Video laser disc
player;
b. objective lens
reading pits on a
laser disc;
c. optical path for
playback showing
tracking mirror rotated by a
control system to keep the
laser beam positioned on
the pits.
(a)
(b)
(c)
© Pioneer Electronics, Inc.
Computer hard
disk drive,
showing disks and
read/write head
Courtesy of Quantum Corp.
High gain; fast but oscillating
Response of a
position control
system showing
effect of high and
low controller
gain on the
output response
Control goal; fast reaction, lower
overshoot, less settling time