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5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii
Status of Type-A suspensions for KAGRA
Yoshinori Fujiifor KAGRA collaboration
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5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii
-- Mechanical installation
-- Servo filter implementation
-- Verification of suspension performance
What is going on?
Status of Type-A suspensions for KAGRA
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5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii
Type-A suspensions?
For the test masses,
- Upper 5 stages: room-temperature
- Lower 4 stages: cryogenic-temperature
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5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii
Type-A suspensions?
INVERTED PENDULUM
(~ 70 mHz)
GEOMETRIC-ANTI SPRING
(~ 0.4 Hz)
IP
F1
F0
F2
F3
BF
4 / 22
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5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii
Type-A suspensions?
INVERTED PENDULUM
with 3 horizontal -- LVDT & actuator units-- inertial sensors
IP
F1
F0
F2
F3
BF
LVDT&actuator
Inertialsensor
LVDT &actuator
GEOMETRIC-ANTI SPRING
with 1 vertical LVDT & actuator unit
5 / 22
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5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii
Type-A suspensions?
BOTTOM-FILTER DAMPERwith 3 horizontal & 3 vertical LVDT & actuator units
BF
(With collaboration of group in Pisa)
6 / 22
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5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii
Type-A suspensions?
JGW-P1809347
Inside cryostat
payload
Heat-linkVIS
+
(+ Wide-angle baffle)
Heat-linkVIS
7 / 22
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5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii
Type-A suspensions?
Platform
Marionette
Intermediate Mass
Mirror
Mirror Recoil Mass &
MarionetteRecoil Mass &
Intermediate Recoil Mass &
Blade Spring
Moving Mass
Reflective photo-sensor &coil-magnet Actuator units
Heat link
Optical lever
Optical lever
JGW-P1808219
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5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii
Then, mechanical installation status
for O3-observation
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5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii
Mechanical installation has done! For all 4 of them!
JGW-G1808885
(Still mechanical-wise repairing work remains though..)
JGW-G1808307
(Finished, for all 4 of them)
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5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii
ETMX & ETMY:
Mass tuning, necessary but no accessibility.
Newly made blades could not hold the system..
ITMX & ITMY:
Hitting,, ~No oscillation
for ETMX - F2 GASfor ETMY - F1 & F2 GAS
for ITMX / ITMY – F0 GAS
Blade replacement, necessarybut time consuming (etc).
Frame
Mechanical installation has done! HOWEVER ..
JGW-G1808283
~Last yearNow
11 / 22
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5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii
Mechanical installation has done! HOWEVER ..
“acceptablefor the O3-run”
(should be)
According to a simulation, assuming 1% coupling,
Requirement
Note: -- Modeled w/o Heat-links-- params are not tuned.
HorizontalDefaultITMX/ITMY caseETMX caseETMY case
w/o controls
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5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii
Servo filter implementation status
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5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii
With displacement sensors, [ for damping ]
IP
BF-damper
Damp
DC+Damp
DC+Damp
For L / T / Yaw
For Yaw
For L / T
Damp
For P / Y(TMoplev)
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5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii
ETMX
ETMX
ITMX
ITMX
PITCHPITCH
YAW YAW
With displacement sensors, [ residuals ]
[ ura
d/r
tHz
] or
[ura
d]
[ ura
d/r
tHz
] or
[ura
d]
0.16 0.41
0.15 0.31
Locked! Thanks to Kamioka environment. 15 / 22
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5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii
ETMX
ETMX
ITMX
ITMX
With displacement sensors, [ residuals ]
[ ura
d/r
tHz
] or
[ura
d]
[ ura
d/r
tHz
] or
[ura
d]
PITCHPITCH
YAW YAW
In bad weather
NOT locked..
0.25 0.56
0.29 0.55
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5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii
Candidate (main) resonant modes? Preliminary
damping at tower-part
damping at payload+ decoupling / inertial damping 17 / 22
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5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii
Verification of suspension performance
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5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii
Measurement:
Mechanical suspension performancewith X-arm cavity
ETMXITMXBSPR3
PR2PRM
Actuation
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5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii
From ground to TM
Vibration isolation ratio, [ Good news! ][
m/m
]
20 / 22
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5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii
From BF-GAS to TM
[ m
/m ]
V to L coupling, [ System is not yet identified.. ]
VTM / BF-GAS(V) * 0.5e-2
Real was not so simple.. 21 / 22
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5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii
Summary:
-- All the Type-A suspensions have been installed.-- Damping controls are working properly, however,
some resonances are not yet damped efficiently.Implement damping controls at payload stages
-- Reducing RMS is necessary when the seismic noise is high.Implement inertial damping at IP stage
For soon next:
Do mode identification including the heat-link peaksDesign the filters in the observation phase.
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5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii
Backup
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5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii
Seismic noise
10-8
Seismic noise (Tokyo)
Seismic noise
(KAGRA site)
Target sensitivity
24
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5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii
Seismic attenuation
x
X
Frequency [ Hz ]
GroundSingleDoubleTriple
KAGRA suspension
Mir
ror
dis
pla
cem
en
tx
[ m
/𝐇𝐳
]
-3010
10.1
-2510
-2010
-1510
-1010
-510
10
Requirement
Mirror(dummy)
Mirror
Ex. KAGRA
3 m
5-stage
(Type-B suspension case)
25
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5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii
Resonance damping
Servo
Actuator Displacement sensor
Active control
Starting interferometer operation
Stable interferometer operation
26
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5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii
1. Calm-down phase
2. Lock-acquisition phase
3. Observation phase
Suppress large disturbance
Reduce RMS velocity RMS angle
(Root-Mean-Square)
Keep positionwith low noise control
Designing active control system / Control phase
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5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii
Type-A suspensions?
JGW-P1809347
Inside cryostat
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5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii
Type-A suspensions?
JGW-P1809382
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5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii
With displacement sensors, [ residuals ] In bad weather
NOT locked..
Seismic motion when the weather was normal/bad(From page #16)
30 / 22
EXV IXV
2.4e-2
1.2e-2
2.6e-2
1.2e-2
[ um
/rtH
z]
or
[um
]
[ um
/rtH
z]
or
[um
]
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5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii
Vertical transfer functions (fitted)
ETMX ITMX
BF-GAS(V) / BF-GAS(V)_act BF-GAS(V) / BF-GAS(V)_act
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5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii
Measurement:
Mechanical suspension performancewith X-arm cavity
ETMXITMXBSPR3
PR2PRM
Actuation
32 / 22
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5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii
Force transfer functions From (TM-RM)-act to TM
???
33 / 22
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5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii
Force transfer functions From (IM-IMR)-act to TM?
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5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii
Force transfer functions From (MN-MNR)-act to TM?
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5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii
(*1) Some resonances have to be identified, as shown in the above.(*2) measurement files are stored under /users/VISsvn/ though, Not much organized well now..
please let me know if you want to have them ASAP.
Excited stage name Degree of freedom
TM L
P
IM L
V
MN L
BF GAS
(L)
IP L
Note: Measurement ofmechanical suspension performance with X-arm cavity
All the local sensors for ETMX and ITMX
Excitation point: Sensing point:
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5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii
#3#2 #4#1 #5 #6
Type-A SAS,
‘TyrpeA180429_20K’
Eigen mode: 75 modes
#8#7
IP translationalmodes
0.067 Hz 0.067 Hz
Less interest now
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5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii
#9 #10 #11 #12 #15#14 #16#13
Less interest now
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5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii
#19#18 #20#17 #21 #22 #24#23
Less interest now
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5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii
#27#26 #28#25 #29 #30 #32#31
Less interest now
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5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii
#35#34 #36#33 #37 #38 #40#39
Less interest now
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5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii
#43#42 #44#41 #45 #46 #48#47
Less interest now
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5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii
#51#50 #52#49 #53 #54 #56#55
Less interest now
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5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii
#59#58 #60#57 #61 #62 #64#63
Less interest now
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5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii
#67#66 #68#65 #69 #70 #72#71
Less interest now
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5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii
#75#74#73
Less interest now
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5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii
WFS
Designing active control system / ex. Type-Bp SAS
DC + Damp
DC
Damp
Damp
DC+Damp
Opticalsensors
Displacementsensor (OSEM)
Displacementsensor (LVDT)
Displacementsensor (LVDT)
Damp
Damp
Damp
DC
DC+Damp
Opticalsensors
Displacementsensor (OSEM)
Displacementsensor (LVDT)
Displacementsensor (LVDT)
Damp
DC
DC+Damp
Damp
DC+Damp
Displacementsensor (OSEM)
Displacementsensor (LVDT)
Displacementsensor (LVDT)
1. Calm-down phase 2. Lock-acquisition phase 3. Observation phase
Damp
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![Page 48: Status of Type-A suspensions for KAGRA...5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii Summary:-- All the Type-A suspensions have been installed.-- Damping](https://reader033.vdocuments.net/reader033/viewer/2022050400/5f7e5c9134327f78114b51f5/html5/thumbnails/48.jpg)
5th KAGRA international workshop on February 14th 2019, Yoshinori Fujii
DC
2. Decay time measurement
Damp
1/e decay time
For damping resonances
We have to measure the decay time constantsw/ and w/o damping controls,in order to verify the damping control performance,FOR ALL THE TYPE-A/B/Bp SUSPENSIONS.
(Example)
For the resonant modes which disturb the lock acquisition.
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