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)
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,- "
." " "
)
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" ! / "
+ - "
+
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'2
Accelerometer
Housing
xo
xi
k
Position
Sensor
m
k
Accelerometer
Housing
xo
b
b
m
Piezo
Crystal
xi
Moving Object
Seismic
Accelerometer
Conductive
Coating
Moving Object
Piezoelectric
Accelerometer
1 $3 0 4
)
) 1 $ " *
! " !
/ " / +$-
5
+5- " / " 1 % 1
6 "
+%-
" "" 0 +$
+%- "
+&-
+'-
* ! / " 7
"
'8
+
I
Ce
Re
Vo
_
1 %3
9" 9 5 :
5
1 +&- +'- " "
+2
) +2- 1
;2$ #&(
/ +2- / , / ) "
"
* *
5
1 & 6
9<
1 &
. +:=9- +8 >
"" " 0 +8- "
" "" "" " :=9 = 1 & 5 5 +?-
) . :=9 +8- "
* '?
u(x,t)
x
L
1 &3 1 <
) +;-
+ / +@-
1
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5 5 +$A
" 9 * /
+;- ) 1 ' 1
+$$-
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1 2 * 7
. B
" + - B "
" . " )" , ';
T1
8
6
Acceleration
4
A1
A2
2
0 0
1
2
A3
3
4
Time
-2
-4
1 '3 / )
/ 4
10
8
Acceleration
6
4
2
0 0
-2
1
2
3
4 Time
-4
-6
1 23 / )
/ 4
'@
15
10
5
0
-5
-10
-15
0
0.02
0
100
0.04
0.06
0.08
0.1
Time (sec)
0.12
0.14
0.16
0.18
0.2
2000
1500
1000
500
0
200
300
400
500
600
Frequency (Hz)
700
800
900
1000
1100
1 83 / 4
1 0 0
/ "
1 8 +$%-
7
B C " " / " 1 1
/
+11/- " 11/
) 4 , /
+ - " ) : 6D 7
5
2A
Beam's
Clamped-end
Accelerometer
Output to A/D
Accelerometer
Charge
Amplifier
Flexible
Beam
Beam's
Free-end
1 ?3 51 < 9 0
) 3
, /
* ) , * ) / 1 ? / /) )E= 6D
$ 0 6D D * / * " "
4
1
* * 5
+@- +$A- 5
% F D * / * " 6D D 4 " " " / 1 ; / /) , * 7
,
2$
Accelerometer
Outputs to A/D
Beam's
Pinned-end
Accelerometer 1
Accelerometer 2
Charge
Amplifiers
Shaker
Power
Amplifier
1 ;3 5: < 9 0
/ * " $ , . , 1
* * 5
+@- +$A- 5
% , " * 5
" "
& F D * / * " %
, " G" " +2+ 1 ;2$ #&(-
$ F D * #$( <
)
7 >
, 7> $@@@
#%( : 9 $@@;
#&(
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6
9 9
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4
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