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• VISMinutes20180511

Agenda/Minutes of the VIS Meeting on 2018/5/11

2018/5/11 13:30 - 15:20

Participants: Takahashi, Enzo, Sato, Fujii, Aso, Hirata, Ohishi, Mark, Tanaka, Ishizaki, Tanioka, Shoda, Akutsu

Progress report

Schedule Chart

Type-A : (PDF/MPP)

Type-B: (PDF/MPP)

Type-A (Takahashi)

Past week report

[X-front]

• Dismounted the PI from the top chamber and lifted up the EQ stop to access the F1.
• Adjusted the position of the yoke in F1.
• Removed one of Cu plates from the F1. Rearranged the magnets on the F1 damper.
• Lifted down the EQ stop. Set the top ring onto the frame lock.
• Installed the PI into the top chamber.
• Suspended the F1. The F1 worked freely.
• Calibrated the LVDT for the TF.
• Cabled from the upper small hexagon to the feedthroughs and checked the cable connections.
• Adjusted compression of the blades.
• Released the IP. The behavior of IP showed overload without any ballast rings.
• Found that the IP unit is not for Type-A but for SR.
• Dismounted the PI from the top chamber.
• Calibrated the LVDTs for BF damper.

[X-end]

• Mirapro fixed the corrugate tube more tightly.

Plan for coming weeks

[X-front]

• Swap the IP and reinstall the PI.
• Tune the IP.
• Set the ACCs.
• Set the LVDT coils for the BF damper.

[SR]

• Check the optimal load of new blade prototype on 15th.

[Exchanging of IPs]

• Separate the PI for SRM to the IP and the TF.
• Transport the IPs from/to 2F.
• Combine the PI and the TF.

Type B (Mark)

Report for week of 5/7

• We inspected the wires and clamps involved in the wire break.
  • The scars on the clamp on the tungsten wire that failed had very different depths, with the one that failed being much deeper, so probably the clamp piece was not completely straight before tensioning. However one wire on the other side was also badly crushed and on the point of failing, so the tension was clearly too much.
  • We decided on new torque specs of 2 N.m for the primary clamps (down from 5 N.m) and 10 N.m (down from 20 N.m) for the secondary. The secondary clamp spec, for M6 screws, is now based on the LIGO policy of using the maximum suggested for the screw and the LIGO value for a coated 1/4-20 screw (100 in-lb = 11.3 N.m), and the primary clamp spec is derated by 2/3 from the spec for an M5 screw because the clamp pieces are recessed and only grip the wire at narrow sections along the edges, concentrating the force.
  • None of the screws showed any signs of damage.
  • All of the scars on the primary clamps were shallow enough that could reuse the clamp pieces. The tungsten secondary clamps were never tightened, and the outer pieces of piano wire secondary clamps were badly scarred but could be reused upside down.
• We successfully rehung the SR3 and RM. In the process we noticed and fixed an issue with the assembly frame (due to an out-of-date number in the Mirapro diagram, the IM crossbars were set 3 mm too high, which would have affected the wire length).
• We added the sections of the security structure below the RM and up to the BF.
• We installed the TM OSEM cables and routed them up to the IM.
• We installed the load gauge adapter and load gauge and prepared the IM/... section for weighing.
• We removed the three cracked F0 blades from the PI #3 in the SRM, and prepared for testing prototype new blades in that PI. We removed a floor panel under the PI and set up the filter service trolley underneath it.
• Mirapro installed the SRM mushroom.
• Shoda is working on 2D drawings of SRM metal mass.

Control issue

• Phase-I measurement done:
  • We measured mainly about the coupling (from vertical to length, rotation to length, check the difference between the IP axis and the optic axis.)
• Analysis ongoing.
• We are working on the discrepancy between the TF measurements using local sensors and Michelson signal.
  • We found the discrepancy in calibration factors of IM OSEMs and Oplevs as well.

Plan for week of 5/14

• Mark, Enzo, Hirata-san, Kozu-kun at Kamioka Mon-Thu, then Osaka.
• Weigh IM/... section.
• Characterize F0 blade prototypes.
• Remove F0 blade prototypes (and send for rework if necessary).
• Start characterizing LBB blades.
• Crane in BF.
• Add IRM top plate, maraging rod, flying saucer.
• Suspend IM, check pitch, roll and vertical, adjust trim mass.
• Cable and (re-)test TM OSEMs, IM picos, BF yaw pico, BF LVDT and FR.

Plan for week of 5/21

• Mark, Enzo, Hirata-san, Kamioka Mon-Fri.
• Kozu-kun at Kamioka Wed-Fri.
• Install IRM sides, and IM OSEMs.
• Center IM OSEMs (in/out and laterally)
• Route all cables to underneath BF.
• Add BF internal ballast mass.
• Add BF cap.

Plan for week of 5/28

• Mark, Enzo, Hirata-san, Kamioka Mon-Fri.
• Kozu-kun at Kamioka Mon only.
• TBD.

To-Do Lists, Schedule

• KAGRA/Subgroups/VIS/TypeB/March2018

• KAGRA/Subgroups/VIS/TypeB/April2018

• KAGRA/Subgroups/VIS/TypeB/ToDoBS

• KAGRA/Subgroups/VIS/TypeB/ToDoSR

• JGW-L1807779 Type B Schedule (SR)

Vacation Info

Type-Bp (Shoda)

Past week report

Plan for coming weeks

OMMT & OSTM (Ohishi)

Past week report

• Have checked the spring constant of the vertical vibration isolation bellows for type-C suspension.
• The constant was about 0.05kgf/mm as required, so I'm asking for a quotation of remaining bellows.
• Have ordered some screws, mechanical parts, and received magnets.

Plan for coming weeks

• As the MCF tank opened, I will check the status of MCo suspension with Kirii-san.
• Continue to order mechanical parts.

LVDT Driver (Tanaka)

LVDT measurement (Enzo)

http://klog.icrr.u-tokyo.ac.jp/osl/?r=4849

Past week report

Plan for coming weeks

Other site works

Safety

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

Discussion

Type-A IP swap

• Next week, ITMX and ITMY IP will be swapped.
  • Aso will ask CRY if ICRR Takahashi-san's help is available or not
• We need to transport the SRM IP (actually a Type-A IP) to 2F, then ITMX IP (actually an SR IP) to 1F. This work will be outsourced to MESCO.
• Then re-assemble those IPs with TFs
• We need those IPs by August. On the other hand, we are short of manpower now, with the prospect of getting more in July. So we will do those works in the middle July.

Metal SRM

• We will push the O-ring with a wedged pipe.
• We should ask Hirose-san to measure the deformation of the mirror surface after mounted to the holder.
• We will start the SRM hanging with the AR coated mirror attached.
• In parallel with the suspension assembly, HR coated mirror with the holder should be inspected.

• Then we apply the first contact on the HR coated one. -> Swap it with the AR coated one. -> Install the SRM suspension. -> Peel of the first contact.

• It is important to make sure the parallelism of the mirror surface and the front surface of the metal mass.
• Shoda will summarized the design concept before proceeding to the production drawings.

PR3 release

• PR3 mirror is fixed to the RM to prevent the large pitch jumps.
• We should release it as soon as possible to see if the problem persists.
• The rease work should be possible with opening the side flanges.

• However, the side flanges may interfere with the OpLev

• We need the OpLev as a reference for the mirror orientation.

• Ohishi will check the interference in the next week.
• Manpower: 2 people are necessary. Arai-kun is available to do this work. Aso will ask Miyo-kun if he is available.

JPS/ASJ talks

• Type-A: Okutomi
• Type-B: Enzo and/or Kozu
• Type-Bp: Arai
• ASJ: Tanioka

Travel Plans

• Travel (Week of 5/14):
  • Takahashi: 14 - 17
  • Okutomi:
  • Sato: 15 - 17
  • Ishizaki:
  • Mark: 14 - 17
  • Hirata: 14 - 17
  • Enzo: 14 - 17
  • Shoda:
  • Ohishi:
  • Fujii:
  • Tanioka: 14 -16
  • Tanaka:
  • Kozu (ICRR): 14 - 17
  • Arai (ICRR):
• Travel (Week of 5/21):
  • Takahashi: 22 - 25
  • Okutomi:
  • Sato: 21 - 25
  • Ishizaki:
  • Mark: 21 - 25
  • Hirata: 21 - 25
  • Enzo: 21 - 24
  • Shoda:
  • Ohishi:
  • Fujii: 21 - 25
  • Tanioka: 21 - 25
  • Tanaka:
  • Kozu (ICRR): 23 - 25
  • Arai (ICRR):

Next meeting

On 2018/5/25(Fri)