Chapter 6 Aircraft Dynamics and Control...飛行力学 Chapter I-6 Aircraft Dynamics and Control 13...
Transcript of Chapter 6 Aircraft Dynamics and Control...飛行力学 Chapter I-6 Aircraft Dynamics and Control 13...
Chapter I-6 Aircraft Dynamics and Control飛行力学
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Chapter 6 Aircraft Dynamics and Control
6.1 Aircraft Model
Chapter I-6 Aircraft Dynamics and Control飛行力学
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Chapter I-6 Aircraft Dynamics and Control飛行力学
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Chapter I-6 Aircraft Dynamics and Control飛行力学
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Chapter I-6 Aircraft Dynamics and Control飛行力学
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x
0
c k
m
u
< Review > Dynamics of Mass-Spring-Damper System (1/7)
(1) Laplace Transformation and Transfer Function
ukxxcxm
Laplace Transformation
susxkcsms 2
Transfer Function in terms of sx su
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2 kcsmss
u
x
Characteristics Equation
0kscsm 2
Chapter I-6 Aircraft Dynamics and Control飛行力学
for : Conjugate Complex Root
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< Review > Dynamics of Mass-Spring-Damper System (2/7)
m
mkccs
2
42
Eigen Values (Roots of Characteristics Equation)
042 mkc
jss 21,m
c
2
m
cmk
2
4 2
2
2
1
1
21
/1
ss
c
ss
c
ssss
ms
u
x
Transfer Function
Chapter I-6 Aircraft Dynamics and Control飛行力学
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< Review > Dynamics of Mass-Spring-Damper System (3/7)
Inverse Transfer Function (Response in Time Domain)
tm
cmke
cmk
tjtec
tjtectu
x
tm
c
t
t
2
4sin
4
2
sincos
sincos
2
2
2
2
1
2121 ,s,s
for : Real Root042 mkc
ttecect
u
x21
21
Chapter I-6 Aircraft Dynamics and Control飛行力学
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< Review > Dynamics of Mass-Spring-Damper System (4/7)
(2) State Equation
vx
ukxcvvm then
BuAxx where
v
xx uu
m
c
m
k10
A
m
10
B
x
0
c k
m
u
Chapter I-6 Aircraft Dynamics and Control飛行力学
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< Review > Dynamics of Mass-Spring-Damper System (5/7)
Laplace Transformation
where
BuAxx s BuxAI s
BuAIx1
s
sm
km
cs
ss
111
AI
m
ks
m
csss 2det AI
Chapter I-6 Aircraft Dynamics and Control飛行力学
u
m
smu
msm
km
cs
v
x
ss
11
101
1
10
< Review > Dynamics of Mass-Spring-Damper System (6/7)
Transfer Function in terms of sx su
kcsmsm
su
x
s
2
11
kcsms
ss
u
v
2
Transfer Function in terms of sv su
Chapter I-6 Aircraft Dynamics and Control飛行力学
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< Review > Dynamics of Mass-Spring-Damper System (7/7)
(3) Damping and Frequency of Mode/ Eigenvalue
ssReal 21 ssjImag
02 22 sss ss
jImagReal
jss ssss
2
21 1,
Eigen Values
where
Frequency :22 ImagReals
Damping :22 ImagReal
Reals
Chapter I-6 Aircraft Dynamics and Control飛行力学
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6.2 Characteristics of Aircraft Motion
(1) Longitudinal Characteristics
e
q
u
u
x
BuAxx
0
M~U
Z
X
e
e
e
o
B
where
0
0
0
0
0
0
~
sin~
1~
~
~
U
ZMMM
U
gMM
U
ZMMM
U
ZMMM
U
ZMMM
e
ee
q
uuu
(4.2-15)
0100
~~~~
sin1
cos
0
0
000
00
MMMM
U
g
U
Z
U
Z
U
Z
gWXX
qu
qu
u
A
Chapter I-6 Aircraft Dynamics and Control飛行力学
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Aircraft Model C <Charlie> (Flight Condition 4)
Linearized Equation Eq.(4.2-15) assuming
Approximate Short Period Mode Eq.(5.2-1), Eq.(5.2-2)
Approximate Phugoid Mode Eq.(5.2-4)0o
Full State Equation Approximate Equations
Longitudinal Mode Characteristics
Eigenvalue Damping Freq.:rad/s
0.0006 + 0.0512i -0.0108 0.0512
0.0006 – 0.0512i -0.0108 0.0512
-0.3785 + 0.8456i 0.4085 0.9264
-0.3785 – 0.8456i 0.4085 0.9264
Short Period Mode Approximation
Eigenvalue Damping Freq.:rad/s
-0.3780 + 0.8453i 0.4082 0.9260
-0.3780 – 0.8453i 0.4082 0.9260
Phugoid Mode Approximation
Eigenvalue Damping Freq.:rad/s
0.0001 + 0.0524i -0.0019 0.0524
0.0001 – 0.0524i -0.0019 0.0524
Chapter I-6 Aircraft Dynamics and Control飛行力学
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Full Calculation
Approximate Calculation
Chapter I-6 Aircraft Dynamics and Control飛行力学
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Full Calculation
Approximate Calculation
Chapter I-6 Aircraft Dynamics and Control飛行力学
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(2) Lateral and Directional Characteristics
r
a
r
p
u
x
BuAxx
00
NN
LL
00
''
''
ra
ra
B
where
r,a,r,p,i
II/I1
LI/INN
II/I1
NI/ILL
zzxx
2
xz
izzxzi'
i
zzxx
2
xz
ixxxzi'
i
: Primed Derivatives
0tan10
0NNN
0LLL
U
cosg1
U
W
U
Y
0
'
r
'
p
'
'
r
'
p
'0
0
0
0
0
A
(4.2-16)
Chapter I-6 Aircraft Dynamics and Control飛行力学
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Aircraft Model C <Charlie> (Flight Condition 4)
Linearized Equation Eq.(4.2-16)
Approximate Dutch Roll Mode Eq.(5.2-5)
Approximate Roll Mode Eq.(5.2-6)
Approximate Spiral Mode Eq.(5.2-7), Eq.(5.2-8)
Full State Equations Approximate Equations
Lateral/ Directional Mode Characteristics
Eigenvalue Damping Freq.:rad/s
0.0120 -1.0000 0.0120
-0.0453 + 0.8088i 0.0560 0.8100
-0.0453 - 0.8088i 0.0560 0.8100
-0.5624 1.0000 0.5624
Dutch Roll Mode Approximation
Eigenvalue Damping Freq.:rad/s
-0.0855 + 0.7740i 0.1098 0.7787
-0.0855 – 0.7740i 0.1098 0.7787
Roll Mode Approximation
Eigenvalue Damping Freq.:rad/s
-0.4700 1.0000 0.4700
Chapter I-6 Aircraft Dynamics and Control飛行力学
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Full Calculation
Approximate Calculation
Chapter I-6 Aircraft Dynamics and Control飛行力学
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Full Calculation
Approximate Calculation
Chapter I-6 Aircraft Dynamics and Control飛行力学
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BuAxx
Cxy
0sdet AI
oc uyyKu
oc BuBKyxBKCAx
0sdet BKCAI
Eq.(6.3-1)
6.3 Feedback Control
State Equation
Observation Equation
Characteristics Equation
Eq.(6.3-2)
Eq.(6.3-3)
Eq.(6.3-4)
Eq.(6.3-5)
Eq.(6.3-6)
ControllerK
AircraftDynamics
ObservationC
yc + u x
y
-
Command
Feedback Control Law
Closed Loop State Equation
Characteristic Equation of
Closed Loop State Equation
Chapter I-6 Aircraft Dynamics and Control飛行力学
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Control
Law
Stability
Augmentation
System
Pitch Rate SAS
Yaw Damper
Yaw Damper (Wash-out Filter)
Beta Dot Damper
Control
Augmentation
System
Pitch Rate Control
RSS Control
Bank Control
Bank Control for Directionally
Unstable Aircraft
Guidance
Law
Flight Path
Guidance
Altitude Control
Direction Control
Design of Guidance and Control Law
in General