Internati
o
nal
Journal of Ele
c
trical
and Computer
Engineering
(IJE
CE)
V
o
l.
5, N
o
. 1
,
Febr
u
a
r
y
201
5,
pp
. 11
1
~
11
8
I
S
SN
: 208
8-8
7
0
8
1
11
Jo
urn
a
l
h
o
me
pa
ge
: h
ttp
://iaesjo
u
r
na
l.com/
o
n
lin
e/ind
e
x.ph
p
/
IJECE
A Universal Formula for Asym
ptotic Stabilization with
Bounded Controls
Muhamm
ad Niz
a
m
Kamar
udin
a
, Abdul Ra
shid
Husa
in
b
,
Mo
ha
ma
d N
o
h
A
h
ma
d
c
,
Z
a
haruddin
Mohamed
d
a
F
acult
y of
El
ec
tric
al
Engin
eerin
g, Univers
i
ti
Te
knika
l
Ma
lay
s
ia
Me
la
ka (UTe
M),
Ha
ng Tua
h
Jaya
,
76100 Durian
Tunggal, Melaka,
Malay
s
ia.
b,c,d
Faculty
of
Electr
i
cal
E
ngineer
ing, Univ
ersiti Teknologi Mala
y
s
ia, UTM Skudai,81310 Johor, Malay
s
ia.
Article Info
A
B
STRAC
T
Article histo
r
y:
Received Oct 14, 2014
Rev
i
sed
D
ec 19
, 20
14
Accepte
d Ja
n
7, 2015
Motivated b
y
Artstein and Sontag univers
al formula, th
is brief paper presents
an explicit proo
f of the univers
al form
ula for a
s
y
m
ptotic s
t
abil
i
zat
ion and
as
y
m
ptotic disturbance
rejectio
n of
a nonlinear s
y
stem
with mismatched
uncertainties an
d time var
y
ing
disturbances.
We prove the stability
v
i
a
Ly
apunov stab
ility
criteria. We
also prove
that the control
law satisfies small
control prop
erty
such that th
e magnitude of th
e co
ntrol signal
can
be bounded
without th
e catastropic ef
fect to
the
cl
osed
loo
p
stability
.
For
clar
ity
,
we
benchmark th
e
proposed approach w
ith o
t
her
method namely
a Ly
apunov
redesign with n
onlinear damping functi
on. We
give a numerical example to
verif
y
the
results
.
Keyword:
Bounded controls
Lyap
uno
v stabilit
y
Nonlinea
r syst
e
m
s
Copyright ©
201
5 Institut
e
o
f
Ad
vanced
Engin
eer
ing and S
c
i
e
nce.
All rights re
se
rve
d
.
Co
rresp
ond
i
ng
Autho
r
:
M
uham
m
ad Ni
zam
Kam
a
rudi
n
Faculty of Elec
trical Engineering
Un
i
v
ersiti Tekn
ik
al Malaysia Melak
a
(UTeM)
,
7
610
0 Du
rian
Tu
ngg
al,
Melak
a
, MALAYSIA
Tel: +6016-2022
457 / Fax
:
+606-
5552222
E-m
a
il
:
ni
zam
k
am
arudi
n
@
ut
em
.edu.m
y
1.
INTRODUCTION
Stab
ilizin
g
syste
m
s with
u
n
certain
ty an
d
ex
og
en
ou
s d
i
st
u
r
b
a
n
ce requ
ires
m
a
ssiv
e
co
n
t
ro
l en
erg
y
.
Fo
r illu
stration, it is
easy
to
stab
ilize u
n
s
tab
l
e syste
m
b
y
forcing
th
eir po
les to
th
e left-h
and
-
si
d
e
o
f
t
h
e S-
p
l
an
e so th
at t
h
e clo
s
ed
-
l
o
op system
stab
le. Th
eor
e
tically, p
l
aci
n
g
th
e cl
o
s
ed
-
l
oop po
les
n
ear to
∞
ren
d
e
r
fast converge
nce rate but require high ene
r
gy as trad
e-
of
f
.
In som
e
i
ndu
st
ri
al
cases are DC drive sys
t
e
m
s
whe
r
e the c
onstraints are
due to th
e
phy
si
cal
l
i
m
i
t
a
ti
on
of t
h
e m
o
t
o
r
dr
i
v
e suc
h
as
conve
r
ter protection,
mag
n
e
tic satu
ratio
n
and
m
o
t
o
r ov
erh
eating th
at
m
a
k
e
th
e cu
rren
t
co
mman
d
limited
to
an
ad
m
i
ssib
l
e
set o
f
input. For a
n
other cas
e suc
h
a
s
electric vehic
l
es whe
r
e th
e co
n
t
ro
lled
v
a
riab
le is a sp
eed
,
th
e m
o
to
r to
rqu
e
or
vol
t
a
ge
m
a
y
be b
o
u
n
d
ed
wi
t
h
i
n
al
l
o
wabl
e
ra
nge
s.
There
are
vari
ous
atte
m
p
ts to
stab
ilize non
lin
ear
syste
m
with
m
i
s
m
a
t
c
h
ed un
certain
t
y
an
d
tim
e
vary
i
n
g di
st
u
r
bance
.
Suc
h
at
t
e
m
p
t
s
have b
een ad
dress
e
d
i
n
[1]
-
[
5]
. I
n
[
1
]
,
a no
nl
i
n
ear
dam
p
i
ng fu
nc
t
i
on i
s
augm
ent
e
d t
o
t
h
e n
o
m
i
nal
cont
rol
l
e
r
du
ri
n
g
t
h
e Ly
ap
u
n
ov
rede
si
g
n
p
h
ase.
In t
h
i
s
p
a
per
,
we
begi
n wi
t
h
no
rm
al
feedba
ck co
nt
r
o
l
l
a
w by
usi
n
g a Ly
apu
n
o
v
re
des
i
gn t
ech
ni
q
u
.
Du
ri
n
g
Ly
ap
u
n
o
v
re
desi
g
n
p
h
ase, a
no
nl
i
n
ea
r dam
p
i
n
g f
unct
i
on
i
s
used t
o
c
o
m
b
at
wi
t
h
unc
ert
a
i
n
t
y
or e
x
oge
n
o
u
s
di
st
u
r
bance
.
B
y
m
e
ans o
f
com
p
ari
ng s
q
u
a
re, we t
h
en i
m
prove t
h
e c
o
nt
r
o
l
l
a
w com
p
l
e
xi
t
y
by
av
o
i
di
ng t
h
e canc
e
l
l
a
t
i
on of a
u
s
eful
n
o
n
lin
ear term
. Lastly, we in
tro
d
u
ce a "un
i
v
e
rsal-lik
e"
formu
l
a to
stab
ilize
th
e syste
m
with
less con
t
ro
l effo
rt.
As su
ch
, m
a
in
o
b
j
ectiv
e o
f
t
h
is p
a
p
e
r is to
p
r
ov
id
e an
i
m
p
r
ov
ed
un
iv
ersal fo
rm
u
l
a d
u
e
to
Artstein
[6] an
d
Son
t
ag
[7-8
], su
ch
t
h
at it can
b
e
app
lied
to
no
n
lin
ear system
s
with
mis
m
a
t
ch
ed
u
n
c
ertainties an
d
tim
e v
a
rying
Evaluation Warning : The document was created with Spire.PDF for Python.
I
S
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08
I
J
ECE Vo
l. 5
,
N
o
. 1
,
Febru
a
ry
2
015
:
11
1
–
11
8
11
2
di
st
ur
ba
nces.
The i
n
t
r
od
uce
d
fo
rm
ul
a i
s
g
e
neral
i
zed
, sim
p
l
e
, ex
pl
i
c
i
t
,
and i
n
a sense
of "u
ni
ve
rsal
",
i
n
ord
e
r
to
ob
tain
g
l
o
b
a
l asy
m
p
t
o
tic stab
ility an
d
g
l
ob
al d
i
st
u
r
b
a
nce rej
ectio
n with
less con
t
ro
l effo
rt.
Let
co
ncer
n si
ngl
e
-
i
n
put
-
s
i
n
g
l
e-o
u
t
p
ut
,
one
-
d
i
m
ensi
onal
n
o
n
l
i
n
ear
sy
st
em
of
t
h
e
fo
rm
:
,
(1
)
with state
∈
an
d
cont
rol
∈
.
and
are analytic, sm
ooth vector
field
s
, wh
ich
are in
fin
itely
di
ffe
re
nt
i
a
bl
e. A
sm
oot
h
fu
nc
t
i
on
,
represen
ts th
e su
m
of
u
n
certain
tie
s a
n
d
exo
g
e
n
o
u
s
di
st
ur
ba
nces.
F
o
r
feedbac
k
stabil
ization, t
h
e e
x
istence
of a
control-Lya
p
uno
v
fun
c
tion
is
n
e
cessary, as in
Artstein
’s t
h
eorem:
“
Artstein
th
eorem sta
t
es t
h
a
t
a
d
y
na
mica
l system ha
s
a
d
ifferen
tia
b
l
e con
t
ro
l-Lyapu
nov
fu
n
c
tion
if
a
n
d
o
n
l
y if there exists a
regu
la
r
sta
b
ilizin
g feedb
a
c
k
”
-
A
r
t
stein
[6
]-
Th
erefo
r
e, th
ere ex
ists a sm
o
o
t
h
,
prop
er
and
p
o
s
itiv
e d
e
fin
ite con
t
ro
l-Ly
ap
uno
v fu
nction
:
fo
r t
h
e sy
stem
in
eq
u
a
tion (1)
where cond
itio
n
s
0
0
,
0
fo
r
0
, a
n
d
⟶
∞
as
‖
‖
⟶
∞
are
v
a
lid
.
Recall fro
m
[8
] th
at th
e ex
isten
ce
o
f
su
ch a co
n
t
ro
l
-
Lyapu
nov
fun
c
tio
n im
p
lies
th
at th
e
syste
m
is
asy
m
p
t
o
tically
con
t
ro
llab
l
e prov
id
ed th
at
the d
e
riv
a
tiv
e
o
f
:
ne
gat
i
v
e
de
fi
ni
t
e
.
As
s
u
ch
,
t
h
ere
m
u
st
be
a
feed
bac
k
c
ont
r
o
l
l
a
w:
,
,
,
0
(2
)
wh
ich
g
l
ob
ally stab
ilize th
e syste
m
in
eq
u
a
ti
o
n
(1
).
No
te t
h
at, fo
r
stab
ility, h
i
gh
con
t
ro
l
mag
n
itu
d
e
∈
is
requ
ired
in
order to
pu
sh
syst
e
m
s p
o
l
es to
th
e left h
a
n
d
side of the s-plane. Thus,
th
e reg
u
l
ar feedb
a
ck law in
equat
i
o
n
(2
) i
s
un
b
o
u
n
d
ed
i
n
m
a
gni
t
ude
, as
wel
l
as hi
gh i
n
ener
gy
c
ons
u
m
pti
on.
O
u
r c
ont
rol
pr
o
b
l
e
m
no
w i
s
to
li
m
it
∈
with
i
n
such that the
closed loop sys
t
e
m
(3
)
rem
a
in
Hu
rwitz and
,
pe
ri
she
d
as
⟶
∞
i
n
or
der
t
o
prese
r
ve a
gl
o
b
a
l
di
st
ur
ba
nce
reject
i
o
n.
2.
M
ETHOD
OLOGY - UN
IVER
SA
L FORM
U
L
A
FOR
R
O
BUST BOU
N
D
E
D CONTR
O
L
C
onsi
d
er
n
onl
i
n
ear sy
st
em
in eq
uat
i
o
n (
1
)
and a
co
nt
r
o
l
-
Ly
apu
n
ov
f
u
nct
i
on
:
. T
h
ere
exist
ope
rato
rs
∈
,
∈
,
∈
, and
∈
, where:
∙
(4
)
∙
(5
)
∙
(6
)
,
(7
)
There
also exis
t a scalar
0
and
0
, su
ch
t
h
at th
e
ro
bu
st
bo
und
ed
co
n
t
r
o
l law
:
,
,
1
1
,
0
(8
)
satisfies
sm
al
l
co
nt
rol
pr
ope
rt
y
fo
r
t
h
e
sy
s
t
em
i
n
eq
uat
i
o
n (1
) (see defi
ni
t
i
on 1
)
a
n
d
al
so gua
rant
ee
s
t
h
e
asy
m
p
t
o
tic stab
ility an
d
t
h
e asy
m
p
t
o
tic d
i
sturb
a
n
ce
rejection
(wh
i
ch m
ean
s ro
bu
st t
o
ward
,
).
Evaluation Warning : The document was created with Spire.PDF for Python.
I
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ECE
I
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8-8
7
0
8
A Un
iversa
l Fo
rmu
l
a fo
r Asymp
t
o
tic S
t
ab
iliza
tion
with
Bou
n
d
e
d
C
o
n
t
ro
ls
(
M
uh
am
m
a
d
N
i
zam
K
a
m
a
r
u
di
n)
11
3
Definiti
on 1
:
Sma
ll C
o
n
t
ro
l Pro
p
erty
For t
h
e sy
stem in e
q
uation
1
sa
tisfies sma
ll co
n
t
ro
l
p
r
op
ert
y
, th
ere is
a
kno
w
n con
t
ro
l
-
Lya
pun
o
v
fun
c
tion
:
. F
o
r
every
0
, there
exists
a
0
so
t
h
a
t
for a
ll
0
a
nd
‖
‖
, there is
contr
o
l
‖
,
,
‖
suc
h
t
hat
,
,
0
.
In
w
h
at
follo
w
s
,
Le
mma 1
is
u
s
efu
l
to reach th
e stab
ility p
r
o
o
f
o
f
th
e rob
u
st bo
und
ed contro
l law in equatio
n
(8
).
Lemma 1
[1]
:
Assume
that
,
in
eq
ua
tion (8
) are rea
l
num
bers.
And th
ere
exists rea
l
numb
e
r
suc
h
that
|
|
, and
0
fo
r
∈
. Th
erefore, th
ere exists
a
no
mi
n
a
l
stabilizin
g
fun
c
tion
,
with
pro
p
ert
y
:
|
,
|
2
|
|
,
(9
)
Proo
f
o
f
Lemma
1
If
0
, th
en
th
e
so
lu
tion
for
,
is triv
ial. Then
,
we assu
m
e
th
at
0
. Since
|
,
|
|
,
|
, the
n
0
and
. I
f
0
, then
|
|
and
0
1
.
W
ith
c
ont
rol
param
e
ter
1
,
we can see that
n
o
m
in
al stab
ilizin
g fu
n
c
ti
o
n
|
,
|
bou
nd
ed
by
as
, an
d also bou
nd
ed
b
y
i
t
s
num
erat
or.
Thi
s
y
i
el
d:
,
1
1
1
1
1
1
2
|
|
,
(1
0)
Proo
f o
f
S
t
ab
il
ity:
By
refe
rrin
g
to
Le
mma 1
, t
h
e
p
r
oo
f of st
ab
ility fo
r th
e ro
bu
st
bo
unded
con
t
ro
l
law
in eq
u
a
tion (8
) is
prese
n
t
e
d
.
W
i
t
h
c
ont
rol
-
Ly
ap
un
o
v
fu
nct
i
o
n
0.5
:
0
,
t
h
e deri
vat
i
v
e of
:
al
on
g
x
ren
d
e
rs
,
1
1
,
1
1
,
1
1
,
1
1
‖
‖
1
1
‖
‖
‖
‖
1
1
(1
1)
Evaluation Warning : The document was created with Spire.PDF for Python.
I
S
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:
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08
I
J
ECE Vo
l. 5
,
N
o
. 1
,
Febru
a
ry
2
015
:
11
1
–
11
8
11
4
W
ith
Le
mma 1
, we
ca
n f
u
rt
h
e
r pr
ove
t
h
at
:
2
|
|
,
(1
2)
Th
is co
m
p
letes
th
e
p
r
oo
f
fo
r asy
m
p
t
o
tic stab
ility. Wh
en
⟶
∞
, ter
m
vanis
h
es t
o
confirm
the
asym
pt
ot
i
c
di
st
ur
ba
nce re
ject
i
o
n
o
f
t
h
e sy
st
e
m
i
n
eq
uat
i
o
n (
1
)
.
3.
N
U
M
E
RICAL EX
AM
PLE
C
onsi
d
er
o
n
e-
d
i
m
e
nsi
onal
no
n
l
i
n
ear sy
st
em
:
,
(1
3)
with state
∈
an
d
cont
rol
∈
. Th
e
un
certain
ty
with ti
m
e
v
a
ryin
g distu
r
b
a
n
ce is den
o
t
ed
as
,
,
(1
4)
In what
follows, we stabilized
the
system
in
equ
a
tion (13
)
su
ch
th
at
th
e
state
∈
i
s
asym
pt
ot
i
cal
ly
stab
le toward
s p
e
rtu
r
b
e
d
i
n
itial state
0
an
d
al
so ac
hi
eve
t
h
e asy
m
pt
ot
i
c
di
st
u
r
ba
nce
r
e
ject
i
o
n t
o
war
d
,
.
W
e
pre
s
ent
t
w
o a
p
pr
oac
h
es
;
a Ly
apu
n
o
v
r
e
desi
g
n
wi
t
h
n
onl
i
n
ea
r
dam
p
ing
fact
o
r
a
nd t
h
e p
r
op
ose
d
bo
u
nde
d c
o
nt
r
o
l
i
n
e
q
uat
i
o
n (
8
)
.
3
.
1
.
Sta
b
iliza
t
io
n using
L
yapuno
v
Redesig
n
a
n
d No
nlinea
r Damping
Functi
o
n
Firstly, let sta
b
ilize syste
m
in
equ
a
tio
n (13
)
u
s
ing
d
i
rect Lyap
un
ov
tech
n
i
q
u
e
with
Lyap
uno
v
redesi
gn
an
d
n
onl
i
n
ea
r
dam
p
i
n
g
f
u
nct
i
o
n
as
add
r
esse
d i
n
[
1
]
.
Let
co
nsi
d
e
r
sy
st
em
13
in
a form
,
,
(1
5)
whe
r
e
i
s
a v
ect
or
of
k
n
o
w
n sm
oot
h
n
o
n
l
i
n
ear f
u
nct
i
o
n
,
an
d
,
,
is th
e
v
ector of
u
n
c
ertain
n
o
n
lin
earities an
d d
i
st
u
r
b
a
n
c
e. Then,
th
e co
n
t
ro
l law rend
ers th
e cl
o
s
ed
-l
o
o
p
system
in
pu
t-to-state stab
ility
for the system
in equation
15
wi
th
resp
ect to
the d
i
stu
r
b
a
n
ce in
pu
t
,
,
. Th
e functio
n
is d
e
no
ted
as a stab
ilizing fu
n
c
tion
for t
h
e no
m
i
n
a
l syst
e
m
in
equ
a
tion (1
5).
|
|
,
0
(1
6)
Lik
e
wise,
for
th
e system
in
eq
u
a
tion (13
)
, let
≡
.
We
firstl
y
seek
for
the no
m
i
n
a
l
un
pe
rt
ur
be
d sy
st
em
i
n
eq
uat
i
on
(
1
3)
. Let
t
h
ere e
x
i
s
t
s
a
co
nt
r
o
l
-
Ly
ap
u
n
o
v
fu
nct
i
o
n
0
.
5
s
u
ch t
h
at
th
e no
m
i
n
a
l sta
b
ilizin
g
fun
c
tio
n
i
n
equ
a
tion
(17
)
rend
ers the d
e
rivativ
e of
al
on
g
be a ne
gat
i
v
e de
fi
ni
t
e
fu
nct
i
o
n (i
.e
.
).
,
0
(1
7)
There
f
ore,
co
m
p
ari
ng e
quat
i
on
(
1
4) a
n
d e
q
uat
i
o
n
(
1
5) y
i
e
l
ds a
vect
o
r
of
kn
o
w
n
sm
oot
h
n
onl
i
n
ea
r
fu
nc
t
i
o
n
(1
8)
an
d a
robu
st st
ab
ilizin
g
fun
c
tio
n
(1
9)
3.
2. C
a
ncel
l
a
ti
on A
voi
d
a
nce
C
ont
r
o
l
l
a
w i
n
equat
i
o
n (
1
9
)
i
s
a st
rai
ght
for
w
ar
d de
si
g
n
based
on
di
re
ct
Ly
apun
o
v
i
n
spi
r
ed
by
Artstein
. Fun
c
tio
n
elim
inates
-t
erm
i
n
t
h
e sy
st
em
equat
i
on
(1
3
)
,
w
h
i
c
h i
s
k
n
o
w
n
as a
use
f
ul
no
nl
i
n
ea
r t
e
rm
. As
s
u
ch
, by
u
s
i
ng t
h
e c
o
m
p
ari
n
g s
qua
re,
we
devi
se
d a
m
e
t
hod t
o
a
voi
d t
h
e
cancel
l
a
t
i
on
of
a
u
s
efu
l
non
lin
ear term
. Let a
g
ain
≡
, an
d rec
a
l
l
a cont
r
o
l
-
L
y
apu
n
o
v
f
u
nct
i
on
0
.
5
. W
e
the
n
o
b
t
ain its d
e
r
i
vativ
e alon
g
x
as fo
llows:
Evaluation Warning : The document was created with Spire.PDF for Python.
I
J
ECE
I
S
SN
:
208
8-8
7
0
8
A Un
iversa
l Fo
rmu
l
a fo
r Asymp
t
o
tic S
t
ab
iliza
tion
with
Bou
n
d
e
d
C
o
n
t
ro
ls
(
M
uh
am
m
a
d
N
i
zam
K
a
m
a
r
u
di
n)
11
5
1
4
1
2
(2
0)
W
i
t
h
that
,
term
in
equ
a
tion
(1
7) can
b
e
redu
ced to
0
.25
(2
1)
and
he
nce
re
du
ci
ng t
h
e c
ont
ro
l
com
p
l
e
xi
t
y
of
eq
uat
i
o
n
(
1
9),
as f
o
l
l
o
w
s
:
1
4
(2
2)
By su
b
s
titu
tin
g eq
u
a
tion
(21) in
to
equ
a
tio
n
(2
0), th
e asym
p
t
o
tic stab
ilit
y c
a
n
b
e
gu
aran
teed
v
i
a th
e d
e
ri
v
a
tiv
e
of
, as fo
llows:
1
2
(2
3)
3.
3. Robus
t
B
o
un
ded Contr
o
l
usin
g Unive
r
sal
F
o
rmul
a
Th
is su
b
s
ection
is d
e
vo
ted
to th
e app
licatio
n
of th
e
p
r
op
osed
un
iv
ersal form
u
l
a in
eq
u
a
tio
n
(8
) to
t
h
e
num
eri
cal
sy
stem
i
n
equat
i
o
n (
1
3).
W
i
t
h
t
h
e co
nt
r
o
l
-
Ly
a
p
u
n
ov
f
unct
i
o
n
0
.
5
, w
e
k
now
fr
o
m
the
st
anda
rd
f
o
rm
i
n
e
quat
i
o
n
(
1
) t
h
at
:
1
,
(2
4)
Th
er
efo
r
e, th
e
r
obu
st bou
nd
ed
co
n
t
r
o
l law
i
s
ob
tain
ed
as:
2
1
1
√
1
,
,
(2
5)
fo
r all
0
,
0
and
0
.
4.
R
E
SU
LTS AN
D ANA
LY
SIS
Th
is section
dep
i
cts sim
u
lati
o
n
resu
lts
for
syst
em
i
n
eq
u
a
t
i
on
(1
3
)
by
usi
n
g a
n
o
r
m
a
l
feed
bac
k
cont
rol
pl
u
s
n
onl
i
n
ea
r
dam
p
i
n
g
f
u
nct
i
o
n
i
n
eq
uat
i
o
n
(2
2)
an
d a
p
r
op
os
ed
bo
u
n
d
e
d
co
nt
r
o
l
l
a
w
i
n
e
quat
i
o
n
(25). Figure
1 shows a stabi
lized
fo
r
t
h
e p
e
rt
u
b
a
tion
o
f
in
itial
state
0
11
. F
i
gu
re 2 s
h
o
w
s
t
h
e
com
p
arison in
cont
rol si
gnal.
Figure
3 s
h
ows
how the c
o
nt
rol signal react
due
to
vari
ation
of t
h
e system state,
.
W
e
ca
n o
b
se
rve t
h
at
t
h
e
si
gnal
pr
od
uce
d
by a bounded
cont
rol law is
confine
d
at
, hence satisfies
sm
a
ll co
n
t
ro
l prop
erty in d
e
fi
n
itio
n
1
.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
S
SN
:
2
088
-87
08
I
J
ECE Vo
l. 5
,
N
o
. 1
,
Febru
a
ry
2
015
:
11
1
–
11
8
11
6
Fi
gu
re
1.
St
abi
l
i
zed st
at
e usi
n
g c
ont
rol
l
a
w i
n
e
quat
i
o
n
(
2
2
)
an
d e
quat
i
o
n
(
2
5
)
Fi
gu
re
2.
C
o
nt
r
o
l
si
g
n
al
f
o
r c
o
nt
r
o
l
l
a
w i
n
e
q
uat
i
o
n
(
2
2) a
n
d
eq
uat
i
o
n
(
2
5)
Fi
gu
re
3.
C
o
nt
r
o
l
si
g
n
al
t
r
a
j
ec
t
o
ri
es
vers
us
s
y
st
em
t
r
aject
or
i
e
s
The co
nt
r
o
l
si
gnal
s
i
n
Fi
g
u
r
e
2 are
no
n
p
er
i
odi
c. T
h
ei
r m
a
gni
t
u
de a
nd c
o
n
v
e
r
ge
nce rat
e
are hi
g
h
l
y
d
e
p
e
nd
o
n
h
o
w far
t
h
e p
e
rt
urb
e
d
i
n
itial
state
0
fro
m
th
e eq
u
ilibria. To
an
alyse th
e
signal q
u
a
n
titativ
ely,
we c
o
m
put
e t
h
e a
v
era
g
e
p
o
we
r a
n
d e
n
e
r
gy
by
usi
n
g
Eul
e
r'
s ap
pr
o
x
i
m
at
i
on (
s
ee
A
ppe
n
d
i
x
).
For
t
h
e
pert
ur
bat
i
o
n
i
n
0
11
, bou
nd
ed
con
t
ro
l law
r
e
quir
e
on
ly
2,
340.
4
Joul
e of ene
r
gy to steer
0
to
ward orig
in.
Wh
ile the
no
r
m
al
cont
r
o
l
re
q
u
i
r
e
12
,101
Joule
of e
n
ergy (see Ta
ble 1).
Tabl
e
1.
A
v
era
g
e e
n
er
gy
pr
od
uced
by
al
l
c
o
n
t
rol
l
a
ws
Control law
Stabilizing
energy (Joule)
Dim
i
nution
(percentage)
E
quation (
22)
12,101
80.
66%
E
quation (
25)
2,340.4
0
0.
0
2
0.
04
0.
06
0.
08
0.
1
0.
1
2
0.
14
0.
16
0.
1
8
0.
2
0
0.
2
0.
4
0.
6
0.
8
1
Ti
m
e
i
n
s
e
c
o
n
d
s
S
t
ab
i
l
i
z
ed
s
t
a
t
e,
x
S
t
a
b
ilize
d
x
u
s
in
g
b
o
u
n
d
e
d
c
o
nt
r
o
l
(
uni
v
e
r
s
a
l
f
o
r
m
ul
a
)
St
a
b
i
l
i
z
e
d
x
us
i
n
g no
r
m
a
l
c
o
nt
r
o
l
w
i
t
h
da
m
p
i
n
g f
unc
t
i
o
n
0
0.
02
0.
04
0.
06
0.
08
0.
1
0.
12
0.
14
0.
16
0.
18
0.
2
0
10
20
30
40
50
60
70
80
90
Ti
m
e
i
n
s
e
c
o
n
d
s
Co
n
t
r
o
l s
i
g
n
a
l
N
o
rm
a
l
co
n
t
ro
l
l
a
w
w
i
t
h
da
m
p
i
n
g
f
unc
t
i
o
n
B
o
unde
d c
o
nt
r
o
l
l
a
w
(
u
s
i
ng un
i
v
e
r
s
a
l
f
o
r
m
ul
a
)
0
0.
1
0.
2
0.
3
0.
4
0.
5
0.
6
0.
7
0.
8
0.
9
1
0
10
20
30
40
50
60
70
80
90
x
Co
n
t
r
o
l s
i
g
n
a
l
,
u
N
o
rm
al
co
n
t
ro
l
l
a
w
wi
t
h
d
a
m
p
i
n
g
fu
n
c
t
i
o
n
B
o
unde
d c
o
nt
r
o
l
l
a
w
(
u
s
i
ng uni
v
e
r
s
a
l
f
o
r
m
ul
a
)
)
D
e
fi
n
i
t
i
o
n
1
u<
(s
e
e
Evaluation Warning : The document was created with Spire.PDF for Python.
I
J
ECE
I
S
SN
:
208
8-8
7
0
8
A Un
iversa
l Fo
rmu
l
a fo
r Asymp
t
o
tic S
t
ab
iliza
tion
with
Bou
n
d
e
d
C
o
n
t
ro
ls
(
M
uh
am
m
a
d
N
i
zam
K
a
m
a
r
u
di
n)
11
7
5.
CO
NCL
USI
O
N
In t
h
i
s
pa
pe
r,
we
prese
n
t
a
u
n
i
v
er
sal
f
o
r
m
ul
a for b
o
u
nde
d c
o
nt
rol
l
e
r w
h
i
c
h
i
s
r
o
bust
t
o
wa
r
d
unce
r
t
a
i
n
t
y
an
d di
st
u
r
bance
.
The p
r
op
ose
d
m
e
t
hod i
s
u
n
i
v
ersal
f
o
r t
h
e
sy
st
em
whi
c
h
affi
ne i
n
co
nt
r
o
l
.
The
appealing feat
ure of the propos
ed cont
ro
ller is th
at, it
is
fairly easy
to
co
n
s
tru
c
t, gu
aran
tee th
e asym
p
t
o
tic
stab
ility an
d
the asy
m
p
t
o
tic d
i
stu
r
b
a
n
ce
rej
e
ctio
n
,
as
well as b
oun
d
e
d
in
th
e con
t
ro
l sign
al m
a
g
n
itu
d
e
. Th
e
n
u
m
erical ex
am
p
l
e an
d
th
e sim
u
la
tio
n
in th
i
s
p
a
p
e
r confirm
th
e resu
lts.
APPE
NDI
X
Fo
r
a con
tin
uou
s sign
al in
Fi
g
u
r
e
4, w
e
can co
m
put
e t
h
e avera
g
e e
n
er
gy
and
p
o
we
r by
usi
n
g E
u
l
e
r'
s
app
r
oxi
m
a
t
i
on. The
ave
r
ag
e e
n
er
gy
f
o
r a c
o
n
t
i
nuo
us
si
g
n
al
sho
w
n i
n
Fi
gu
r
e
4:
‖
‖
(2
6)
T
h
e
av
e
r
ag
e po
w
e
r
f
o
r
a c
o
n
t
in
uo
us
s
i
gn
a
l
in
F
i
g
u
r
e
4
:
≅
∆
∆
(2
7)
whe
r
e
is th
e n
u
m
b
e
r of in
t
e
g
r
al part in
Eu
ler's ap
prox
i
m
atio
n
,
i
s
t
h
e cont
r
o
l
si
g
n
al
du
rat
i
on a
n
d
∆
/
is th
e
du
ration (o
r i
n
terv
al)
for each
in
teg
r
al
p
a
rt i
n
seco
nd
s.
Fi
gu
re
4.
Eul
e
r
’
s a
p
p
r
oxi
m
a
t
i
on
ACKNOWLE
DGE
M
ENTS
We ack
nowled
g
e
th
e Min
i
stry o
f
Edu
c
atio
n
Malaysia, Un
i
v
ersiti Tek
n
i
k
a
l Malaysia Melak
a
(UTeM
)
an
d the Un
iv
ersiti Tek
n
o
l
og
i Malaysia (UTM
) for research
facilities
and
research
co
llab
o
ration.
REFERE
NC
ES
[1]
M.
N.
Kamarudin,
A.
R.
Husain and M.
N. Ah
mad, "Control of Un
certain Non
linear Sy
stems using
Mixed Nonlinear
Damping Function and Backstep
ping Techn
i
ques
"
,
IEEE Int
e
rnat
ional Conferen
c
e
on Control System, Computing
and Engin
eering
, pp
. 105–109
, 2
012.
[2]
M.T. R
a
vich
and
r
an and
A.D. M
a
hindrak
ar, "Robust Stabiliz
atio
n of a C
l
ass of
Under
actu
a
ted Mechanical
S
y
stems
Using Time Scaling a
nd Ly
apu
nov Redesign",
IEEE Transacti
ons on Industrial Ele
c
troni
cs
,
vol. 58, pp
. 429
9–
4313, 2011
.
[3]
M.
N.
Kamarudin,
A.
R.
Husain and
M.N. Ah
mad, "Stabilization of uncer
tain
s
y
stems using backstepp
i
ng an
d
Ly
apunov red
e
sign",
The
4
th
In
ternational Gra
duate Conferen
ce
on Eng
i
neering Scien
ce
&
Humanity
, Joho
r,
Malay
s
ia, 2013
.
[4]
H.H. Choi
, "An expli
c
i
t
form
ula of
lin
ear
s
l
iding s
u
rfa
ces
f
o
r a
clas
s
of
u
n
cert
a
in d
y
n
a
m
i
c s
y
s
t
em
s
with
m
i
s
m
atched unc
erta
inti
es
",
Au
to
matica
, vol. 34
,
pp. 1015–1020
,
1998.
[5]
H.H. Choi, "A new method for variab
le
structu
r
e contro
l s
y
stem design: A
linear
matrix ineq
uality
approach",
Automatica
, vo
l. 33, pp. 2089–20
92, 1997
.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
S
SN
:
2
088
-87
08
I
JECE Vo
l. 5
,
N
o
. 1
,
Febru
a
ry
2
015
:
11
1
–
11
8
11
8
[6]
Z. Artst
e
in
, "Sta
biliz
ation
with
r
e
lax
e
d con
t
rols",
Nonlinear
Analysis, Theory
, Methods and App
lications
, vo
l. 7, p
p
.
1163–1173, 198
3.
[7]
L. Yuandan
and
E.D. Sontag
, "A universal fo
r
m
ula for stabilization with boun
ded controls",
Sy
ste
m
s &
Contr
o
l
Letters
, vo
l. 16,
pp. 393–397
, 19
91.
[8]
E.D. Sontag
, "A Universal Construction of
Ar
tstein Th
eorem
on Nonlinear St
abili
za
tion",
Sys
t
em and Control
Letters
, vo
l. 3, p
p
. 117–123
, 198
9.
BIOGRAP
HI
ES OF
AUTH
ORS
M
uhammad Ni
zam K
a
mar
udin
was born in Selangor, Malaysia, in 1979
. He receiv
ed the
B.Eng (Hons.) Electri
cal from
t
h
e Universiti
T
e
knologi MARA, Malay
s
ian in 2
002, and M.Sc
Automation and Control from t
h
e University
o
f
Newcastle Upon Ty
ne, United Kingdom in
2007. He is curr
entl
y
with th
e Universiti
Teknik
a
l Malay
s
i
a
Mel
a
ka (UTeM). He is the m
e
m
b
er
of the Board of Engineers, Malay
s
ia and Institut
e of Engineers
,
M
a
la
y
s
ia
. His
res
earch int
e
res
t
s
includ
e nonlin
ear controls and r
obust control s
y
st
ems. Before jo
ining UTeM, h
e
worked as a
techn
i
cal
engineer at
the magn
etr
on depa
r
t
ment o
f
Samsung El
ectronics Malay
s
ia.
Abdul Rashid
Husain
receiv
e
d
the B
.
S
c
.
degr
e
e
in
el
ectr
i
c
a
l
a
nd com
puter
en
gineer
ing from
The Ohio State University
, Colu
mbus, Ohio, U.S.
A, in 1997, M.S
c
. degr
ee in Mechatronics from
University
of
Newcastle Upo
n
Ty
ne, U.K.,
in
2003, and Ph.D. in Electrical Engineering
(Control) from
Universiti T
e
kn
ologi Malay
s
i
a
(U
TM) in 2009. Before join
ing UTM, he worked
as an engineer in semiconductor
industr
y
for seve
ral
y
e
ars specializing in precisio
n molding and
IC trimming process. He h
a
s
taught courses in introdu
ction
to electrical engin
eer
ing
,
microcontroller
based
s
y
s
t
em, m
odeling and control, and real-tim
e control s
y
s
t
em
. His
res
earch
inter
e
sts include
applic
ation of
control in d
y
namic sy
stem, network c
ontrol s
y
s
t
em
, real-
tim
e
control s
y
stem, and s
y
st
em
with d
e
la
y.
M
o
hamad Noh
Ahmad
receive
d the Ba
che
l
or d
e
gree
in E
l
e
c
tri
c
al Eng
i
nee
r
ing f
r
om
Universiti
Teknologi Malay
s
ia in 1986
, the M.Sc. d
e
gree
in Contro
l Engineer
ing from University
o
f
Sheffield
,
U.K.
in 1988,
and Ph.D. degr
ee
in R
obotics from Universiti Tekno
lo
gi Malay
s
ia in
2003. Curren
t
ly he
is Associate Professor with
the Depar
t
ment of Co
n
t
rol and Mechatronic
Engine
ering, Fa
cult
y of Ele
c
tr
ic
al Engine
erin
g
,
Universiti Tekn
ologi Mala
ysia
.
Since joining
Universiti
Tekn
ologi Mal
a
y
s
ia, his prim
ar
y
res
ponsibiliti
es in
clude
resear
ch
and teach
ing in
Robotics and
C
ontrol Eng
i
neering. His resear
ches involve among others
modeling and
control
of numerous plants such as Ac
tiv
e Magnetic Bear
ing S
y
stem, Balancing Robot
, an
d
Direct-Drive
Robot Manipu
lator.
Zahar
u
ddin
M
o
hame
d
is
an As
s
o
ciate P
r
ofes
s
o
r at the Departm
e
nt
of Control and
M
echatron
i
cs
E
n
gineer
ing,
F
acul
t
y
o
f
E
l
e
c
tri
cal
E
ngineer
ing,
Univ
ers
iti
Tekno
logi
M
a
la
y
s
ia
. He
rece
ived
B.Eng
in E
l
ec
tric
al
and
El
ectron
i
cs
Eng
i
neer
ing from
N
a
tion
a
l Univ
ers
i
t
y
o
f
M
a
l
a
y
s
ia
in 1993, M.Sc and Ph.D. in Con
t
rol S
y
stems Engi
neer
ing from the University
o
f
Sheffield, UK
in 1995
and 200
3 respectively
.
He was a recipien
t of
Islamic Developm
ent Ban
k
(IDB) Merit
Sc
hola
r
ship for his Ph.
D
.
study
. His re
se
a
r
c
h
interests includ
e command
shaping control of
d
y
nam
i
c s
y
s
t
em
s
,
contro
l of
fl
ex
ible
s
t
ructur
es
a
nd m
echatron
i
c
s
y
s
t
em
s
.
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