Differences between revisions 146 and 206 (spanning 60 versions)
Revision 146 as of 2017-05-26 10:54:56
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Editor: MarkBarton
Comment:
Revision 206 as of 2017-11-24 11:10:42
Size: 1319
Editor: MarkBarton
Comment:
Deletions are marked like this. Additions are marked like this.
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At Kamioka (Mark, Fabian, Enzo, Hirata-san):
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 * Inspected LLB in tank - in a good position, but not very clean - apparent water spots and dirt.
 * Found the geophone adapter plates.
 * Retested SF FR stepper - still good.
 * Finally got SF LVDT working:
  * Found a short in the primary coil due to Al foil used for mechanical reinforcement at vacuum feedthrough connection.
  * Did a full calibration and found that linear range was too small (0.75 mm!) and did not cover nominal keystone height.
  * Decreased gain to increase linear range.
  * Adjusted the height of the yoke and secondary coil unit to center the linear region around the nominal keystone height.
  * Implemented velocity damping.
 * Found all parts for the LBB and damper rings.
  * Cu segments and some other parts were very dirty - wiped carefully for now, but should be properly cleaned before final install.
  * Outrigger parts for LBB have M16 thread cut directly into Al but should have had M16 helicoils. This is a galling risk with Ag-coated rod receptacles. Hirata-san organized rework.
  * Some special lock nuts are in short supply and are being borrowed from supply at ATC for next batch of BFs.
 * Made remaining two geophone in-air descrambler cables (total three).
 * Installed a thermometer supplied by Kokeyama-san on the tower around the BS tank.
 * Prepared the SF damper.
  * Designed a pattern of magnets for the two-segment arrangement of SF damper and laid it out on the magnet ring with the template.
  * Moved the Cu segments on SF cap by 30° (the cap had not been in the right position earlier).
 * Reinstalled PI:
  * Raised the PI with the crane and hooked the SF damper ring. Some of the rods did not fit the receptacles due to tolerance issue, but by going through a large number of rods and receptacles, we found three working sets.
  * Craned the PI onto the frame and suspended the SF/... section, this time with the hex cable clamp on the F0-SF rod.
  * Tensioned the PI yaw return spring, installed (but did not cable) the yaw stepper and adjusted the yaw of the SF/... section. We worry the return spring is not stiff enough.
  * Installed (but did not cable) the geophones.
  * Recentered the IP. The extra weight from the geophones (≈42 kg) and SF damper ring (≈17 kg) had brought the IP to near the point of instability, so we removed one arc weight (≈17 kg) and rearranged the other two in the top row to be symmetrical.
  * Added ballast to set the height of the F0 keystone. We now have about 6 kg in hand (due to removing one of the Cu segments for the SF damper). This should be enough margin for cables, temperature fluctuations etc.
 * Mark and Fabian did a huge cleanup of the SR2 area and prepared a workspace for assembling the IM.
 * Fabian did a stocktake of the screws for the SR.
  * We have all we need for the IM, except one type that can be added after the rest of the IP is assembled.
  * We have most of what we need for the rest of the payload, and Hirata-san has ordered the others.
 * Hirata-san worked on SR procurement:
  * Suspension wire
  * SR additional parts (compensation masses, clamps etc)
  * Regular, SDC and BUMAX screws.
  * Additional machining on the BS sapphire prism jig to allow it to be used on the PR/SR mirror box.
  * LBB blade design.
 * Enzo and Kozu-kun (with help from Fujii-kun) worked on export from SUMCON to Matlab, and on filter design.
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==== Plan for coming weeks ====
For more detail, see [[KAGRA/Subgroups/VIS/TypeB/ToDo]].
==== Plan for week of 11/20 ====
 * Holiday on Thu 3/23
 * All at Mitaka.
 * SR procurement, planning (Mark, Hirata-san)
 * SR mass budget (Fabian)
 * BS modeling filter design (Enzo, Kozu-kun)
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Weeks of 5/22, 5/29:
 * Retest SF stepper every day, to see if problems recur.
 * Find/install geophone adapter plates or improvise replacement.
 * Reinstall PI, this time with rods and damper ring.
 * Reinstall PI-SF rod, this time with hex cable clamp.
 * Cable/test PI geophones LVDTs and steppers.
 * Reinstall LBB blade units.
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    ==== Plan for week of 11/27 ====
 * Fabian at commissioning workshop
 * Hirata-san at Kamioka to work with Mirapro on SRM LBB installation.
 * All others at Kamioka to start SR2 assembly.

Scraps of text for incorporation in the VIS Meeting Minutes

KAGRA/Subgroups/VIS/MeetingNAOJ

Type B (Mark)

Past week report

  • Mark and Fabian did a huge cleanup of the SR2 area and prepared a workspace for assembling the IM.
  • Fabian did a stocktake of the screws for the SR.
    • We have all we need for the IM, except one type that can be added after the rest of the IP is assembled.
    • We have most of what we need for the rest of the payload, and Hirata-san has ordered the others.
  • Hirata-san worked on SR procurement:
    • Suspension wire
    • SR additional parts (compensation masses, clamps etc)
    • Regular, SDC and BUMAX screws.
    • Additional machining on the BS sapphire prism jig to allow it to be used on the PR/SR mirror box.
    • LBB blade design.
  • Enzo and Kozu-kun (with help from Fujii-kun) worked on export from SUMCON to Matlab, and on filter design.

Plan for week of 11/20

  • Holiday on Thu 3/23
  • All at Mitaka.
  • SR procurement, planning (Mark, Hirata-san)
  • SR mass budget (Fabian)
  • BS modeling filter design (Enzo, Kozu-kun)

Plan for week of 11/27

  • Fabian at commissioning workshop
  • Hirata-san at Kamioka to work with Mirapro on SRM LBB installation.
  • All others at Kamioka to start SR2 assembly.

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