Differences between revisions 192 and 200 (spanning 8 versions)
⇤ ← Revision 192 as of 2017-09-22 13:57:37 →
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Editor: MarkBarton
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Editor: MarkBarton
Comment:
Deletions are marked like this. Additions are marked like this.
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At Kamioka (Mark, Ohishi-san, Fabian, Enzo, Hirata-san, Yoshioka-kun, Kozu-kun):
 * We put lock nuts on the F0 FR and calibrated the F0 LVDT against FR position and keystone height.
 * Enzo traced the issue with the geophones to a specific cable.
 * We measured the BF and F0 GAS resonant frequencies.
 * We adjusted the spacing of the SR damper.
 * We double-checked the BS pitch with the OL.
 * We debugged the PI yaw mechanism. We managed to get the return spring properly adjusted, but the stepper motor tends to jam because of the strange design.
 * '''We prepared the suspension for lifting and craned it into the tank.'''
 * Hirata-san fixed an issue with one of the nailheads on the LBB intermediate ring support rods not properly seating, by removing the rod and reinstalling it upside down (with the problem nailhead in a less critical position).
 * Enzo and team moved all the in-air cables from the assembly frame to the tank.
 * Fabian and Ohishi-san unlocked the bottom section of the suspension and got it hanging freely.		 At Kamioka (Mark, Ohishi-san, Fabian, Enzo, Hirata-san, Kozu-kun):
 * We couldn't account for a bubble level, so we removed a service port cover, searched again on top of the BF and found it.
 * We put the table KOACH filters on the table. Ohishi-san then removed the FC in two stages (AR side on Tue, HR side on Fri).
 * Ohishi-san measured the height of the SS and optic relative to the tank and found the optic was 3 mm low but the SS was 2 mm high. According to the GAS LVDTs, the suspension had not sagged but was 1.7 mm high.
 * Therefore we raised the suspension by 9 quarter-turns of the tank jacks (4.5 mm) so that the optic would be in the right position after (future) downward adjustment of the GAS filters.
 * We put the GAS LVDT calibration data as offsets and gains in the LVDTINF filters so the output would be height in µm relative to nominal.
 * We calibrated the IP LVDTs. We had worked around a mechanical interference due to the poor design of the old LVDTs by setting them to be 4 mm off-center with the IP locked centrally, but we discovered this was overkill and we have lost some linear range on the LVDT sensor in the opposite direction. If we have time we may move the LVDT bases 1-2 mm to a compromise position.
 * We worked with Simon to get the OL aligned and to learn the adjustment procedure.
 * Mark updated Sekiguchi-san's SUMCON to allow for comments to be entered next to all values (75% finished).
 * Kozu-kun worked on deriving the diagonalization matrices for the IP FRs.
Line 19: Line 18:
==== Plan for week of 9/25 ====
Mark, Fabian, Enzo (Mon, Tue), Ohishi-san (Tue, Fri), Hirata-san, Yoshioka-kun (Tue, Wed, Fri), Kozu-kun
 * Finish moving in-air cabling and feedthroughs and reconnect in-vacuum cables (through Cu O-rings).
 * Unlock rest of suspension and readjust.
 * Debug electronics.
 * Unclamp LBB ring "sandwich" so LBB Cu ring is suspended on upper rods.
 * Install LBB lower rods and hook LBB.
 * Adjust LBB damper Cu-magnet gap.
 * Measure required ballast for LBB.
 * Remove First Contact, try OL.
 * Prepare for SR2 work.		 At Mitaka (Hirata-san):
 * Hirata-san met with manufacturers and requested quotes.
 * Hirata-san made many assembly drawings for sections of the SR.
 * Hirata-san worked on compiling the SR inventory.
Line 31: Line 23:
==== Plan for week of 10/2 ====
Kamioka: Mark, Enzo, Fabian, Ohishi-san.
 * TFs etc.
Mitaka: Hirata-san?
 * SF design/purchasing.		 ==== Plan for week of 10/16 ====
Kamioka: all but Mark
 * Remove sticker residue and permanent marker writing on PI.
 * Fix broken and unreliable connections on IP LVDTs.
 * Wipe any rust from around IP LVDTs.
 * (If Enzo thinks it necessary and there's time) adjust IP LVDT mechanical offsets to maximize usable range and recalibrate.
 * Add IP LVDT gains and offsets to IP_LVDTINF filter blocks.
 * Calibrate IP LVDT actuation against IP LVDT sensing.
 * Install damping filters for IP LVDTs.
 * Adjust gains and debug damping for IM OSEMs and GAS LVDTs.
 * Modify IP LVDT damping filters to include set point.
 * Install and debug IP LVDT and geophone diagonalization matrices.
 * (Time permitting) Try adding mass to IP.
 * Work with alignment team.
 * Work with Mirapro on SR LBB and tank installation (Hirata-san, from Wed)
 * Work with Miyo-kun to get user interface for stepper motors.
 * Calibrate IP FR actuation against IP LVDT sensing.
 * SR procurement.
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Enzo: 9/27-29

Scraps of text for incorporation in the VIS Meeting Minutes

KAGRA/Subgroups/VIS/MeetingNAOJ

Type B (Mark)

Past week report

At Kamioka (Mark, Ohishi-san, Fabian, Enzo, Hirata-san, Kozu-kun):

  • We couldn't account for a bubble level, so we removed a service port cover, searched again on top of the BF and found it.
  • We put the table KOACH filters on the table. Ohishi-san then removed the FC in two stages (AR side on Tue, HR side on Fri).
  • Ohishi-san measured the height of the SS and optic relative to the tank and found the optic was 3 mm low but the SS was 2 mm high. According to the GAS LVDTs, the suspension had not sagged but was 1.7 mm high.
  • Therefore we raised the suspension by 9 quarter-turns of the tank jacks (4.5 mm) so that the optic would be in the right position after (future) downward adjustment of the GAS filters.
  • We put the GAS LVDT calibration data as offsets and gains in the LVDTINF filters so the output would be height in µm relative to nominal.
  • We calibrated the IP LVDTs. We had worked around a mechanical interference due to the poor design of the old LVDTs by setting them to be 4 mm off-center with the IP locked centrally, but we discovered this was overkill and we have lost some linear range on the LVDT sensor in the opposite direction. If we have time we may move the LVDT bases 1-2 mm to a compromise position.
  • We worked with Simon to get the OL aligned and to learn the adjustment procedure.
  • Mark updated Sekiguchi-san's SUMCON to allow for comments to be entered next to all values (75% finished).
  • Kozu-kun worked on deriving the diagonalization matrices for the IP FRs.

At Mitaka (Hirata-san):

  • Hirata-san met with manufacturers and requested quotes.
  • Hirata-san made many assembly drawings for sections of the SR.
  • Hirata-san worked on compiling the SR inventory.

Plan for week of 10/16

Kamioka: all but Mark

  • Remove sticker residue and permanent marker writing on PI.
  • Fix broken and unreliable connections on IP LVDTs.
  • Wipe any rust from around IP LVDTs.
  • (If Enzo thinks it necessary and there's time) adjust IP LVDT mechanical offsets to maximize usable range and recalibrate.
  • Add IP LVDT gains and offsets to IP_LVDTINF filter blocks.
  • Calibrate IP LVDT actuation against IP LVDT sensing.
  • Install damping filters for IP LVDTs.
  • Adjust gains and debug damping for IM OSEMs and GAS LVDTs.
  • Modify IP LVDT damping filters to include set point.
  • Install and debug IP LVDT and geophone diagonalization matrices.
  • (Time permitting) Try adding mass to IP.
  • Work with alignment team.
  • Work with Mirapro on SR LBB and tank installation (Hirata-san, from Wed)
  • Work with Miyo-kun to get user interface for stepper motors.
  • Calibrate IP FR actuation against IP LVDT sensing.
  • SR procurement.

Vacation Info

Mark: 10/16-24

KAGRA/Subgroups/VIS/TypeB/Minutes (last edited 2022-10-28 10:02:46 by fabian.arellano)