coil balancing for ETMY

[YoshinoriFujii]

Note

• The dir of this issue will be replaced with more suitable one soon. (Noted on 10th May.)

Todo

1. inject a line with appropriate actuators
2. check the P- or Y-oplev spectra with L exc with 4 of them, and check if the amplitude of peak(s) are reduced or not.
3. do the iteration
4. check the performance once the work above has finished.

[YoshinoriFujii]

For ETMY:

the data is stored: spectra => /users/VISsvn/TypeApayload/ETMY/Spectra/20190510 tf => /users/VISsvn/TypeApayload/ETMY/TF/20190510

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• free-swinging spectra before staring this work

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• mechanical TF in (L/)P/Y

  • TMPexc to TMPoplev

• TMYexc to TMYoplev

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• Coil polarity TM-stage:

  • It seemed that the polarities of the TM-actuator swapped between H1 and H4.
  • When we inject a dc-offset of 10,000cnt to H1, we found negative Yaw at TMoplev.
  • When we inject a dc-offset of 10,000cnt to H4, we found positive Pit at TMoplev.

  IM-stage:

  • Note: when we inject a dc-offset to V1, we found TM-Yaw change like:

  • The other photos are in /users/VISsvn/TypeApayload/ETMY/Spectra/20190510/

  MN-stage: done

see klog#8844

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• inject a line for the balancing
  • inject a line at ~12 Hz to for PIT, ~4Hz for YAW.