ETMXのGASのループの確認

[YoshinoriFujii]

Background

• From the ITMX fact, I wanted to check the status and the idea of the filters

Ref

• measured mechanical TFs
  http://klog.icrr.u-tokyo.ac.jp/osl/?r=8765

[YoshinoriFujii]

Status check

• start configuration:
  

• F0GAS
  -SUsMod looks the latest one.
  

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• F1GAS
  

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• F2GAS is not avaiable

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• F3GAS
  

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• BFGAS

[YoshinoriFujii]

Before starting

[YoshinoriFujii]

modification plans

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• F0GAS
  
• red: the currently implemented one
• blue: which would be tested, the plan 1 (dcdamp_plan1)
• green: the plan 2 (dcdamp_plan2)
• Maybe I want to have infinite at lower frequency region.

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• F1GAS
  

• blue: the currently implemented one

• red: which would be tested, the plan 1 (dcdamp_test)

• green: the plan 2 (dc_plan)

• Should I tale care of infinite amp. at lower frequency?

---

• F3GAS

• blue: the currently implemented one
• green: which would be tested, the plan 1 (dcdamp_test)
• red: the plan 2 (dc_plan)
• Should I tale care of infinite amp. at lower frequency?

---

• BFGAS
  

• blue: the currently implemented one

• green: which would be tested, the plan 1 (dcdamp_test)

• red: the plan 2 (dc_test)

[YoshinoriFujii]

2019.9.25 modification work

• starting point:
  

---

• After modification
  

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NOTE: LOOK_AT_TME!

• I found that when I closed (dc+damp) for all the stages, it stated oscillating. Something looks weird, to be checked.

[YoshinoriFujii]

For 2019.9.25th 13:18JST condition:

• I returned to the initial condition:

[YoshinoriFujii]

data:
/users/VIS/TypeA/general/LogNotes/20190924/ETMX

[YoshinoriFujii]

2019.9.26 long-term performance check

performance test

• F0dcdamp + F1/F3/BFdc
  

---

• F0F1dcdamp + F3/BFdc
  

• One peak appeared at ~2.8Hz. Did we have resonance?

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• F0F3dcdamp + F1/BFdc
  

---

• F0F3BFdcdamp + F1dc
  

• The RMS is reduced in the best, however, It looks that BF actuator is exciting a resonance at 2.8Hz.

[YoshinoriFujii]

Note

• DO NOT FORGET TO ADD A NOTCH AT 9.7Hz.
  

[YoshinoriFujii]

I have added ~9.7Hz notch to all the F0/1/F3/BF-GAS loops.

[YoshinoriFujii]

check w/o controls

[YoshinoriFujii]

sensor polarity looks aligned among the stages

at /users/VISsvn/TypeAtower/ETMX/Measurements/TF/Measurements/20190926/F1_GASexc.xml

[YoshinoriFujii]

Note: when the following configuration was used, F1-GAS start ringing up at 2.7Hz:

• This was observed at on F0, F1 and F3. The oscillation was not observed in BF-stage.

---

• It looks due to a shortage of phase margin.
  -F1GAs was excited with F0dcdamp:
  

[YoshinoriFujii]

2019.9.26, I finished with

[YoshinoriFujii]

2019.9.27

old filter information:

• at ETMX_F0_DAMP_GAS:
  • Filter7: notches
    notch(0.7244,10,30)notch(0.9462,10,30)notch(1.2823,10,30)notch(1.4454,10,30)

[YoshinoriFujii]

• btw, the modal sensor for Mode1 looks working somehow.

  • check the F0exc TF for the sensors,
  • For actuators?
    

• For actuators, starting from (F0, F1, F2,F3, BF) = (1,1,1,1,1), and then diagonalizing it, would work?

[YoshinoriFujii]

Log on 2019.11.16

• F0GAS loop modification:
  • try to shape the filters as:

stage	current nominal [1]	modification on Nov. 16th [2]
F0	dc+damp (UGF_2Hz)	dc+damp (UGF_4.4Hz)
F1	dc	dc
F2	---	---
F3	dc+damp	dc
BF	dc	dc

[1] FM5 (blue)
[2] FM7 (red)

[YoshinoriFujii]

Note 2019.11.16

stage	configuration
F0	dc+damp (UGF_2Hz)
F1	dc
F2	---
F3	dc+damp
BF	dc

• 0.6Hz: appeared a bit though.

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stage	configuration
F0	dc+damp (UGF_2Hz)
F1	dc
F2	---
F3	dc
BF	dc