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• VISMinutes20200807

Agenda/Minutes of the VIS Meeting on 2020/8/7

2020/8/7 14:00 - 14:50

Zoom Meeting

Participants: Takahashi, Fabian, Miyo, Aso, Hirata, Terrence, Shoda, Sato, Tanaka, Washimi

Progress report

General

• [Miyo] by 08/28/2020?, 20% done (+0%), Make a cabling diagram for O4

• [Miyo] by 08/28/2020?, 25% done (+0%), Make prototype system for temperature control

• [Miyo] by 08/28/2020?, 20% done (+0%), Enable to control the limit switch of stepper motor

• [Miyo] by 08/28/2020?, 0% done (+0%), Request AEL chassis for picomotor driver

• [Miyo] by 08/28/2020?, 0% done (+0%), Update remote control system

• [Miyo] by 08/28/2020?, 0% done (+0%), Add CRY stepper motor in the remote control system

Type-A

• [Miyo] Installed the Prequa system in TypeA

  • (This week) Installation was finished. Now I try to diagonalize sensors and balance actuators by using the Prequa system.
  • (Next week) I will do the modal damping on TypeA suspensions after the initialization work for sensors and actuators.

Type-B

• On Monday I submitted the paper to CPC: JGW-P2011860.

• Noise budget paper: I calculated upper limits to DAC and coil driver noise contribution to DARM for the BS: klog 14875.

Type-Bp

• Noise budget paper: Fabian calculated upper limits to DAC and coil driver noise contribution to DARM for PRM: klog 14876.

Type-C

• Brainstorming meeting for IMMT2 modification was held yesterday. We discussed the modified shape of the outer frame and how to replace it. The plan is to replace the frame without removing IMMT2 from the chamber.

Controls

• Updated the sensor correction path in the Type-A modeling. The simulated signals at IP stage fitted well to the actual signal when the sensor correction accuracy is about 90 %.

  • With the updated control model, the TM displacement at micro-seismic motion was reduced by about 10 times. Therefore, the actuation efficiency should be about 10 times smaller than the design value to be consistent with the measured FB signal. If I roughly estimate the actuation efficiency, it is almost consistent with what CAL team measured.14864

• I observed the pendulum wobbling when the asymmetry is introduced in the suspension wires. 14868

Electronics

• Evaluated the modified LVDT cards (grounding of the demodulator chip).

Towards O4

• KAGRA is in "Upgrade phase for O4". Prequa system was implemented to the Type-A.
• Confirmation of personnel at the site.
  • Type-A team: Takahashi, Sato, Miyo, + Company(Jan-Apr)
  • Type-B/Bp team: (Shoda,) Hirata, Fabian, Washimi, + Company(Oct-Dec)
• Procedure documents are required by SEO.

  • Type-A tower

  • Limit switches

  • Wire gluing in PR3 (by Shoda)
  • Filter height adjustment in Type-B (by Fabian)
  • Replacement of TF blades (by Takahashi)

• Schedule towards O4 (Chart) was revised.

cf. Post Obs. task (Request), Task for O3c (Plan, Sheet), Task towards O4 (List).

Safety

• [Washimi] Room Temmperature report(https://www.icrr.u-tokyo.ac.jp/~washimi/KAGRA/SEM/fig_GAS/)

  • We turned on the FFUs in CS and Y-end on 2020-8-3 to recover the room temperature (klog14851) ->RT becames about the same as before the heavy rain.

  • BS temperature was droped (~0.6 degC) in this morning (klog14879) -> The Ondotori was dropped.

Discussion

Travel Plans

Next meeting

• On 2020/8/19(Wed)