COMPUTER SIMULATION OF CONTROL SYSTEMS
PREAMBLE
Simulation allows one to study the behavior of a system
before it is actually constructed. This can serve as an aid
to system design. Simulations are inexpensive and easy to
put together. They can handle all

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DIGITAL PHENOMENA
Today, most systems are controlled by digital computers. Within a
computer control loop, sampling of sensor signals is usually done
first
followed
by
calculation
of
control
signals
followed
by
control signal construction using ZOH. The t

SYSTEM PERFORMANCE
Often the dynamics of a control system is dominated by a pair of
roots just to the left of the imaginary axis in the S plane. All
other roots are much further to the left and have transients which
die away very quickly. In such cases, t

Nonlinear Systems
Perspective on Nonlinear Systems
All systems are nonlinear, especially if large signals are considered. 0n the
other hand, almost all physical systems can be well approximated by linear
models if the signals are small. For

AUTONOMOUS UNDERWATER VEHICLE
NYQUIST APPLICATION
To illustrate application of the Nyquist Procedure we will
consider the task of controlling the submergence depth of a
small autonomous underwater vehicle or auv. The equations
governing the motion of the

ROOT LOCUS CONCEPT
For a feedback control system 1+GH=0 when S is a root of the
overall characteristic equation for the system.
This implies that
when S is a root GH=-1. So at a root the magnitude of GH is 1 and
its angle is plus or minus 180o. The Root L

REVIEW OF LAPLACE TRANSFORMATION
Laplace Transformation converts ordinary differential equations or
ODEs into algebraic equations or AEs. Manipulation of the AEs
followed by Inverse Laplace Transformation gives responses back in
time.
Manipulation
of
the

AUTONOMOUS UNDERWATER VEHICLE
ZIEGLER NICHOLS GAINS
To illustrate a procedure for getting Ziegler Nichols gains,
we will consider the task of controlling the submergence
depth
of
a
small
autonomous
underwater
vehicle
or
auv.
According to Newton's Second L

AUTOMATIC CONTROL ENGINEERING
FEEDBACK CONTROL CONCEPT
The sketch on the next page shows a typical feedback or error
driven control system. What has to be controlled is generally
referred to as the plant. What the plant is doing is known as its
response.

NONLINEAR CONTROLLERS
Systems with nonlinear controllers often undergo finite amplitude
oscillations known as limit cycles. When a system with a nonlinear
controller is undergoing a limit cycle, its behavior resembles that
of a borderline stable linear sy

NONLINEAR PHENOMENA
Linear theory predicts that, when an unstable system is disturbed
from a rest state, the transients which develop grow indefinitely.
For example, when transients are oscillatory, the oscillation
amplitude tends to as time tends to . In

MEMORIAL UNIVERSITY OF NEWFOUNDLAND
FACULTY OF ENGINEERING AND APPLIED SCIENCE
ENGINEERING 6925
AUTOMATIC CONTROL ENGINEERING
DATE : THURSDAY 9 DECEMBER 2010
INSTRUCTOR
TIME : 9:00 AM TO 12:00
M. HINCHEY
NOON
The equations governing the
speed of a certain

MEMORIAL UNIVERSITY OF NEWFOUNDLAND
FACULTY OF ENGINEERING AND APPLIED SCIENCE
ENGINEERING 6925
AUTOMATIC CONTROL ENGINEERING
DATE : THURSDAY 9 DECEMBER 2010
INSTRUCTOR
TIME : 9:00 AM TO 12:00
M. HINCHEY
NOON
The
equations
governing
the
proportional
contr

3
+ b S2 + c S + d =
a S
0
x = bc - ad
a S4
+
b S3
c S2
+
+
b S4
+
x = bc - ad
c S3
+
d S2
+
+at
+ (X+Yj) e
+
+ 2X e
+at
+xt
e S
+
+
f
KD = KP*TD
TD = 0.125*TP
B e
+(x+yj)t
+ (G+Hj) e
A e
+
KI = KP/TI
TI = 0.5*TP
A e
e = 0
+jt
B e
= 0
z = (dx - by)y - x2f