Agenda/Minutes of the VIS Meeting on 2019/6/21

2019/6/21 13:30 - 14:38

Zoom Meeting

Participants: Terrence, Fabian, Takahashi, Hirata, Sato, Mark, Shoda, Fujii, Aso, Okutomi, Tanaka, Ishizaki

Progress report

Type-A (Takahashi)

Past week report

• Checked stock parts.
• Sent back a spare ACC unit to Mitaka for developments.

News

• ITMY
  • we decided to go with current configuration for the time being.
• ETMY
  • During a measurement, YF kicked IP accidentally and the orientation of ETMY went away.
    • Everything should be free now since BFYexc and MNexc transfer functions looked consistent with the ones measured before this kick.
    • Only the orientation was changed somehow.
    • We decided to open the chamber. The cryocooler was turned off already.

  • During another measurement. it was found that F3-GAS was working properly at the current position (klog#9293).

    • since the shapes of the GAS mechanical transfer functions were changed from the precious ones, I updated the modeled transfer function and filters in the filter-bank.

Building damping system for payload

• ITMX / ETMY
  • I started to measure the mechanical transfer functions with Photo-sensors for building.
    • ETMY-MN/IM * 6dof, done. Sensor/actuator diagonalization is necessary indeed.

RT-model, MEDM, guardian updates

Plan for coming weeks

• Modify/install RT-model
• update MEDM, guardian
• tune the filters

Type B (Mark)

Past week report

Report for the week 6/17 (written by Fabian)

• Izum-san pointed out the SR3 oplev control loop was not able to damp resonances at 1.4 Hz and 1.2 Hz (klog 9290). Terrence checked (klog 9299):

  • He found that the optic TFs were coupled to about 10%. I assume something changed because, as far as I understand (Fabian), the oplev had been succesfully diagonalized before to less than 1% coupling.
  • He moved the IP and compared IP LENGTH with OPLEV LENGTH noting the the oplev was reading only 70% of the IP displacement.
  • In this conditions he diagonalized the oplev but failed. There was still coupling.
  • He introduced a factor to have the OPLEV LENGTH measurement equal to IP LENGTH measurement.
  • He successfully diagoinalized the oplev.
  • He then proceeded to checked the filter but he was unable to reduce the residual motion. Noise is the suspect. Having appropriate wind shield is recommended.
• Fabian worked in rolling-off the control filters of the GAS filters.

  • According to klog 8979 the GAS filter control noise has to decrease by 5 orders of magnitude in order to meet the requirement at 10 Hz.

  • A Butterworth filter of order 20 with a cut-off frequency of 5 Hz seems to reduce the noise but renders the system unstable.
  • More work is necessary.
• Fabian joined Enomoto-kun's lecture on how to align the X Fabry Perot cavity with green light.

• VIS simplified monitor is available. 9298.

Plan for the week 6/24

• Fabian will continue working in the rolling-off of the filters of the GAS filters control loops.
• Improve VIS monitor
• Help commissioning

Leftover

• Lock filters for gound motion common-mode rejection.
• SR3 inertial damping, windshield.
• Type B operation manual.

Vacation/Travel Info

• Terrence goes back to Hong Kong on 7/27.
• Mark's final day 6/28.

Type-Bp (Shoda)

Past week report

Plan for coming weeks

OMMT & OSTM (Takahashi)

Past week report

• Checked stock OSEMs. There are 17 units.
• Disassembled the pillars of the MC suspension for modification.
• Ordered the modification parts.
• Making the overall 3D model around OMC.

Plan for coming weeks

• Schedule(PDF/MPP)

VIS electronics (Tanaka)

Past week report

Plan for coming weeks

Other site works

Safety

• Incidents:
• Foreseen risks
  • Type-A:
  • Type-B:

Discussion

DAQ channel reduction

• List

Realtime model update policy

• Make local copies of the relevant files (.mdl, MEDM files etc) to modify an existing RTM.
  • Once the modifications are complete, you can deploy the modified files by replacing the existing ones.
• Notify the relevant people (kagra-seis and gokagra ML) in advance (more than a day) of the deployment of the modified RTM.
• Deployment should be complete.
  • Do not attempt a partial update, such as changing only ETMX. Update all the suspensions of the same kind (Type-A, B, Bp) at once, unless there is a good reason to do so.
  • Update MEDM screens at the same time to reflect changes in the RTM.
  • People can test the modified RTM during non-interferometer-commissioning time, i.e. in the morning.
    • After the test, the RTM should be reverted to the original one, before the interferometer commissioning starts.

Where to put the hardware WDS ?

• Type-Bp: GAS LVDT ?
• Type-B: IP ?
• Type-A: IP ?

POS table cover box

• Box-with-panel.pdf

• Box-without-panel.pdf

• Explanation.docx

Travel Plans

• Travel (Week of 6/24):
  • Takahashi:
  • Sato:
  • Mark:
  • Hirata:
  • Shoda:
  • Fujii: 26-28
  • Tanioka:
  • Tanaka:
  • Terrence:
• Travel (Week of 7/1):
  • Takahashi:
  • Sato:
  • Mark:
  • Hirata:
  • Shoda:
  • Fujii: 1-4
  • Tanioka:
  • Tanaka:
  • Terrence:

Fujii: Amaldi 7/6-14

Next meeting

On 2019/6/28(Fri)