Introduction to
Automatic Control
Systems
Basic Information
• Instructor Contact Information
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Degang Chen, 2134 Coover Hall
djchen@iastate.edu; 294-6277
Office Hour: MWF 12:00 – 2:00 pm
Or any other time convenient to you
– Please include "EE475" in the subject line in all email
communications to avoid auto-deleting or junk-filtering
• TA
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Jon Watson, 3201 Coover Hall
Office Hour: 1:00-2:00 pm, TR, ALC Village B, #6
E-mail: jonrwat@gmail.com;
Voice phone: 515-520-9569
Class Webpage
• http://class.ece.iastate.edu/djchen/ee475/2009
• Please check the page for
– Any announcement
– Class notes
– HW assignments
– Lab assignments
– Project requirements
– Class policy and other info
Final Grade Weighting Schedule
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Homework average: 15%
Midterm exam1: 20%
Midterm exam2: 20%
Final exam: 30%
Quizzes: 15%
Discretionary bonus: 0-5%
Fixed Grading Scale:
A:
B+:
B–:
C:
F:
95 – 100%
85 – 90 %
75 – 80%
65 – 70%
<60%
A–:
B:
C+:
C–:
90 – 95%
80 – 85%
70 – 75%
60 – 65%
Student behavior expectations
• Full attendance expected, except with priornotified excuses
• On-time arrival
• Active participation
– Ask questions
– Answer questions from instructor or students
• Be cordial and considerate to students and TA
• 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
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
Catalog Description
• E E 475. Automatic Control Systems.
(3-0) Cr. 3. F.Prereq: 324. Stability and
performance analysis of automatic control
systems. The state space, root locus, and
frequency response methods for control
systems design. PID control and lead-lag
compensation. Computer tools for control
system analysis and design. Nonmajor
graduate credit.
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 EE 475, 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
Textbook
• Automatic Control Systems, Golnaraghi
and Kuo, ninth edition, Wiley, 2009
• Price: $114.84 & this item ships for FREE with
Super Saver Shipping.
• 20 new from $86.04 7 used from $101.57
Other References
• Feedback Control of Dynamic Systems (6th Edition) by
Gene Franklin, J.D. Powell, and Abbas Emami-Naeini
(Hardcover - Oct 11, 2009) Buy new: $150.00 $120.00
• Modern Control Engineering (5th Edition) by Katsuhiko
Ogata (Paperback - Aug 30, 2009) Buy new: $150.00
$135.00
Other References
• Modern Control Systems (11th Edition) (Pie) by Richard
C. Dorf and Robert H. Bishop (Hardcover - Aug 10,
2007) Buy new: $159.00 $115.32 65 Used & new from
$104.97
• Control Systems Engineering, Just Ask! Package by
Norman S. Nise (Hardcover - Jun 21, 2004) Buy
new: $140.60 28 Used & new from $7.00
Other References
• Modern Control Theory (3rd Edition) by William L.
Brogan (Paperback - Oct 11, 1990) Buy new: $150.00
$133.34 22 Used & new from $120.41
• Feedback Control Systems (4th Edition) by Charles L.
Phillips and Royce D. Harbor (Hardcover - Aug 19, 1999)
Buy new: $159.00 $121.62 35 Used & new from $99.97
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 email to your instructor describing the situation. If you
notice anyone cheating, please report it to the instructor
or the TA. Do not deal with it yourself.
Discrimination
• State and Federal laws as well as Iowa State University
policies prohibit any form of discrimination on the basis
of race, color, age, religion, national origin, sexual
orientation, gender identity, sex, marital status, disability,
or status as a U.S. veteran. Language or gestures of
discriminatory nature will not be tolerated. Severe cases
will be reported to appropriate offices. See ISU policies
at http://www.hrs.iastate.edu/hrs/files/reaffirmation.pdf
• Let us make every effort to work together and create a
positive, collegial, caring, and all-supportive learning
environment in our classroom, laboratory, TA office, 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 Student Disability Resources at the
Academic Success Center to initiate the
accommodation process.
Accommodation for
religion based conflict
• Iowa State University welcomes diversity
of religious beliefs and practices,
recognizing the contributions differing
experiences and viewpoints can bring to
the community. Students with religion
based conflict should talk to the instructor
and appropriate university offices to
request accommodations at the earliest
possible time.
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
Types of Control Systems
Open-Loop
– Simple control system which performs its
function with-out concerns for initial conditions
or external inputs.
– Must be closely monitored.
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
 Increased Accuracy
– Increased ability to reproduce output with varied
input.
 Reduced Sensitivity to Disturbance
– By self correcting it minimizes effects of system
changes.
 Smoothing and Filtering
– System induced noise and distortion are reduced.
 Increased Bandwidth
– Produces sat. response to increased range of input
changes.
Major Types of Feedback Used
Position Feedback
– Used when the output is a linear distance or
angular measurement.
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
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
Idle-speed control system.
Figure 1-5 (p. 5)
Solar collector field.
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
The control system design process
Aircraft attitude defined
Winder
© J. Ayers, 1988.
Control of a nuclear reactor
Grinder system
© 1997, ASME.
High-speed proportional
solenoid valve
© 1996, ASME.
High-speed rail system showing
pantograph and catenary
© 1997, ASME.