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• VISMinutes20190125

Agenda/Minutes of the VIS Meeting on 2019/1/25

2019/1/25 13:30 - 14:45

Zoom Meeting

Participants: Takahashi, Sato, Mark, Tanaka, Ohishi, Aso, Lucia, Fabian, Fujii, Enzo, Ishizaki

Progress report

Schedule Chart

Site work schedule: XLSX

Type-A : (PDF/MPP)

Type-B: (PDF/MPP)

Type-C: (XLSX)

Type-A (Takahashi)

Past week report

[Y-front]

• Adjusted the tilt of BF arranging the location of ballast masses.
• Adjusted the yow position of IP. Set the operation point at 5mm from the center in CW.
• Adjusted the yaw position of BF using the yaw FR in the TF.

[X-front]

• To improve the motion of yaw FR in the TF, added the coil springs with side bar on the receptacle.
• The strength to pull back the receptacle was increased, but still not enough.
• One horizontal FR in the IP reached at the limit, it was recovered.
• Adjusted the position of IP by the jacks and the horizontal FR.

[Y-end]

• Locked the IP.

Plan for coming weeks

• Finalization of yaw FR in X-front (Feb 5-6).

Type B (Mark)

Past week report

BS (top priority)

• Last Friday: We tuned the IP to have a lower frequency. At the beginning we measured 78 mHz.
• Last Friday: With Lucia, we centered the IP and diagonalized the IP. After this process we measured a resonant frequency of 40 mHz. We closed the position control loop for the IP.

• We checked during the weekend and the suspension was not in a healthy state. We checked the IM horizontal OSEM coil driver, and there were some cables in the wrong connectors (Test In instead of Drive Input). Note by Mark: THIS IS INTENDED! The coil drivers default to Test In unless a certain bit is activated in the BIO.

• The adapter for the cable of the F0 fishing rod was not healthy. We fixed it but it might be good to replace it.
• The commissioning team steered the BS IM to reach the Y-end and then Terrence centered the OL with this orientation (more than once).
• Fujii-san and Enzo fixed damaged BS geophones by replacing the preamps.
• We replaced the geophones with the recently fixed ones.
• Hirata-san and Fabian secured trim masses to the keystone.
• We installed GAS filters and IM control loops
• Currently Terrence and Enzo are centering the IP using the horizontal fishing rods.

SR2 (priority 2)

• We measured the optic height. According to the measurement it was 0.1 mm off. However, the systematic error is likely larger (laser level, position of reference). Apparently, the RM has a small amount of roll but this should be investigated further. It might just be systemaric error of the measurement. The roll of IM was adjusted to a value close to zero before the measurement.
• We calibrated the F0 fishing rod stepper motor.
• We raised the suspension using the jacks. We rotated the jacks by ≈180 degrees each. Compensation has to happen with F0, F1 and BF.
• We removed tape, writing etc on PI and PI items.
• We removed the trim mass.
• Terrence restored the OL to the original layout with an 1.1 m collimator and calibrated the tilt sensing QPD. We expect a pitch range of +/-223 urad and a yaw range of +\-322 urad.
• We centered the IP by using the jacks. L and T came good but there is a large yaw of ≈5 mrad.

• We diagonalized the IP actuation matrix. We closed the position control loop for the IP. (This has not happened yet).

• We installed GAS Filters and IM control loops. (This has not happened yet).

SR3 (priority 2)

• The buoyancy correction was calculated: 1.3 mm.
• The strategy is raising the suspension by 1.3 mm and then moving the keystone by 1.3 mm with the fishing rod so the alignment team can work.
• We measured the optic height using Terada-san's reference. The SR2 optic was at the correct height.
• We raised the suspension using the jacks by an amount calculated with the jack thread: M42 with 2 mm special thread. We rotated the jacks by approximately 180 degrees.
• Terrence reinstalled the OL LED, collimator (1.1 m) and realigned the OL. Both QPDs were calibrated and we expect a range of L: $\pm$332 $\mu m$, P: $\pm$217 $\mu rad$ and Y: $\pm$306 $\mu rad$.
• OPLEV diagonalization hasn't been done but we expect minimal coupling due to the OPLEV. Strange couplings (due to the geometry of TM) are expected but no conclusive results yet.
• We removed tape, writing etc on PI and PI items.
• We calibrated the F0 FR against the readout of the F0 LVDT. We removed the trim masses (110 g). Then we moved the F0 keystone by 1.3 mm downwards.
• We centered the IP by adjusting the height of the jacks by small amounts. Longitudinal and transverse positions came good but there was a large yaw (-5 mrad) when the stepper motors were in mid-range. Currently the yaw is -1 mrad and the steppers are using 80% of their range already.
• The F0 yaw stepper should, in principle, give plus minus 125 mrad range. We should check with a measurement how good this range is (e.g. cables being pulled, components touching, etc.) We can use the vertical laser level as an oplev or the main interferometer beam

• The front of the optic was cleaned by Hirose-san with Hirata-san's help. Hirata-san and Fujii-kun released the optic. The IP is still locked.

• F1 fishing rod is not responsive. We have to check the cables.

• We diagonalized the IP actuation matrix. We closed the position control loop for the IP. (This has not happened yet).

• We installed GAS Filters and IM control loops. (This has not happened yet).

Talk about problems turning on and off control systems (Terrence and Enzo) From Terrence: Since the PI controller was implemented, the controller keeps accumulator displacements error and converts this error to the output. One problem arose from the mismatch of the control system and the actual hardware. Because the controller output could have a much larger value than the number of counts that can be input to the coil actuators (e.g. the controller says we should input 60000 counts to the actuators but the hardware limits the number of counts), the controller will not function as designed. As a result, the PI would shift to one side (due to insufficient driving force) while the voices coils became saturated at maximum output. Additionally, because the controller is still functioning, the integrator keeps accumulating error and hence the output of the controller keeps increasing but the object is actually stuck. This makes the IP very very unstable when the actuators are saturated.

SRM (low priority)

• Hirose-san, Hirata-san and Fujji-san fixed the RM to the SS and removed the SRM for cleaning.
• Terrence installed the optical breadboards on the shelfs for the OPLEV; and, assembled the beamsplitter assembly, lens assembly and the folding mirror assembly. The LED box, collimator and the fibre connected were placed on the lower breadboard and the others are placed on the upper one. Still missing steering mirror to complete a tilt setup and a lens for the length OPLEV.

Plan for coming weeks

Type-Bp (Shoda)

Past week report

Plan for coming weeks

OMMT & OSTM (Ohishi)

Past week report

Plan for coming weeks

VIS electronics (Tanaka)

Past week report

Plan for coming weeks

Other site works

Safety

• Incidents: no incident
• Foreseen risks
  • Type-A: no work
  • Type-B: Crane work

Discussion

Updated KAGRA schedule

• 1/23 BS will be aligned to Y-end PD by IR.
• 1/24-25 ITMX will be aligned to REFL by IR.
• 1/24-25 ITMY will be aligned to REFL by IR.

SR2 and SR3 must be ready: 1/26

• 1/26 Beam position of IR at SR3 will be confirmed how far from the center.
• 1/28-29 SR3 will be aligned to SR2 center by IR.
• 1/30 Green beam will be injected from SR2 AR surface to Y end PD.
• 1/31 Removing bellows at PR and SR area.
• 1/31-2/1 Cleaning HR of PR3 and AR of SR2

SRM must be ready: 2/4

• 2/4-8: Alignment of SR2 -> SRM by IR, SRM -> OMMT by IR -> OMMT -> OSTM by IR, OSTM -> OMC by IR

• 2/4-8: Alignment of ETMY -> POS by Green

• 2/12-13: Close the center area chambers
• 2/14-15: Center area pump down.

Vacuum monitoring

• 2/14(Thu)-15(Fri): Center area pump down
• 2/15(Fri) - 2/16(Sat): ITMX, ITMY, pump down
• 3/6(Wed)- 3/7(Thu): ETMY pump down
• 3/21(Thu) - 3/22(Fri): ETMX pump down

Travel Plans

• Travel (Week of 1/28):
  • Takahashi:
  • Okutomi:
  • Sato:
  • Lucia:
  • Fabian:
  • Mark: 28-31
  • Hirata: 29 - 1
  • Enzo: 28-1
  • Shoda:
  • Ohishi:
  • Fujii: 28-1
  • Tanioka:
  • Tanaka:
  • Terrence: 28-1
• Travel (Week of 2/4):

  • Takahashi:4-8

  • Okutomi:
  • Sato: 5-6
  • Lucia:
  • Fabian:
  • Mark: 4-8
  • Hirata:
  • Enzo: 4-8
  • Shoda:
  • Ohishi:
  • Fujii: 4-5
  • Tanioka:
  • Terrence

Next meeting

On 2019/2/1(Fri)