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Revision 327 as of 2018-09-21 11:02:53
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Revision 351 as of 2018-12-01 20:05:47
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Deletions are marked like this. Additions are marked like this.
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==== Report for week of 9/17 ====
 * Monday 9/17 was holiday.
 * We optimized the trim mass on the SF to get more balance torque with less total mass. We now have a reserve of 480 g for the yaw pico.
 * We set the SF damper gap to 6 mm.
 * We set the SR2 pitch with the optic lever, aligned the IRM and set all the OSEMs to have good clearance and midrange output.
 * We locked the SR2 suspension (except for the SF) and craned it into the tank.
 * We moved the vacuum feedthroughs over to the tank.
 * With help from Ohishi-san, we removed the First Contact from SR2.
 * Mark did an audit of all the electronics boxes and updated the item list and S-number file cards on JGWDoc.
 * Mark did an inventory of some thin arc weights and finalized the number to order (8*38 mm + 9*10 mm).
 * Panwei copied control filters over from the SR3.
 
==== Plan for week of 9/24 ====
 * Monday 9/24 is holiday (Autumn Equinox).
 * Mark, Hirata-san, Fabian, Panwei at Kamioka Tue-Fri.
===== SR2 =====
 * Remove First Contact.
 * Move SR2 in-air cables.
 * Unlock and realign suspension.
===== SRM =====
 * Set pitch of SRM and RM, tighten clamps, remove winch system.
 * Weigh IM/... section.
 * Build up SS to BF level.
 * Add BF.
 * Suspend IM and tweak height/balance.

==== Plan for week of 10/1 ====
 * Mark, Hirata-san, Fabian, Panwei at Kamioka Mon-Fri.
===== SRM =====
 * Cable/test BF.
 * Install IRM.
 * Install/cable/test IM OSEMs.

==== Plan for week of 10/8 ====
 * Monday 10/8 is Sports Day.
 * Mark and Terrence (plus TBD) at Kamioka Mon-Fri.
 * Hirata-san, Fabian and Panwei at Kamioka Tue-Fri.
===== SR2 =====
 * Terrence to set up LEN half of SR3 OL and, time permitting, TILT and LEN for SR2.
===== SRM =====
 
==== Report for week of 11/19 ====
 * BS
  * Fabian did some debugging on the BS and found that the calibration for the F0 LVDT was off due to an Excel error, and that the sag wasn't quite the 7 mm originally observed, but still enough to cause the suspension to touch down. Enzo tried applying LVDT actuation at the GAS filters and got it to lift off far enough to get sensible TFs, but the required BF offset was enough to put the IM OSEMs at the very edge of their usable range, so this is not a good long-term solution. We can probably raise the F0 keystone during the vent by removing mass and/or installing an auxiliary spring, which will then allow us to return the BF keystone to nominal height.
  * While working on the BS, Enzo noticed that one of the stepper drivers was not responding. It turned out to be water damaged from the rain issues earlier in the year. Enzo and Fujii-kun opened the rest of the BS chassises on the second floor but they seem to be OK. Tanaka-san had made a third driver chassis as a spare, so we reserved that and will install it in the week of 12/10.
 * SRM
  * The SRM-W optic arrived and we installed it in place of the SRM-M in the metal mass, taking care to use 1.4 mm shims as recommended by Hirose-san. The weight of the new assembly was within 1 g of the old and did not disturb the height of the payload. There was a very small change in pitch which we corrected with the IM picos.
  * We installed the shelf for the OL receiver.
  * We added the arc weights and geophones and went through several rounds of improving the centering of the IP and then realigning the security structure back to vertical.
  * We calibrated the F0 LVDT, and checked the F0 and IP actuation signs.
  * We adjusted the SF trim masses to set the SF pitch and roll, did an inventory of the trim mass and set the damper gap.
  * We did a final alignment of the whole chain and left the suspension ready for TFs during the f2f week. There is only a few hours of work left before we can install and we hope to do that on Monday 12/10.
 * SR2
  * Enzo replaced the geophones and cables that had been borrowed for calibration and did several rounds of optimization of the IP frequency. He got as low as 46 mHz but with poor Q and so backed off a bit to 55 mHz and may back off a tiny bit more.
  * I derived updated IP matrices for the BS and SR, with more precise geometry data provided by Hirata-san, and published them as T1707205 and T1807663.
  * I created a CENTERING screen for the IP, with large panel meters for the LVDT signals and the derived L, T and Y signals.
  * Enzo confirmed that the fancy stepper control screen created by Shoda-san worked.
  * We installed a modified LPCD as IM-V for testing.
 * SR3
  * We moved HPCDs from BS and SR2 to replace the ones that had been stolen from SR3, so as to create a working suspension with an OL for Kozu-kun.
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==== Vacation/Visitor Info ====
 * Enzo: 9/14 JPS, 9/15 through 10/8 vacation in Chile.
 * Terrence: 10/8-12, 10/29-11/2 at Kamioka.

==== Plan for week of 12/3 ====
 * f2f Meeting at NAOJ - no Kamioka work.
==== Plan for week of 12/10 ====
 * Crane SRM into tank.
 * Install new F0 yaw mechanisms on SRs.
 * Remove First Contact from SRM, unlock and realign.
 * Move SRM in-air cables over.

Scraps of text for incorporation in the VIS Meeting Minutes

KAGRA/Subgroups/VIS/MeetingNAOJ

Type B (Mark)

Report for week of 11/19

  • BS
    • Fabian did some debugging on the BS and found that the calibration for the F0 LVDT was off due to an Excel error, and that the sag wasn't quite the 7 mm originally observed, but still enough to cause the suspension to touch down. Enzo tried applying LVDT actuation at the GAS filters and got it to lift off far enough to get sensible TFs, but the required BF offset was enough to put the IM OSEMs at the very edge of their usable range, so this is not a good long-term solution. We can probably raise the F0 keystone during the vent by removing mass and/or installing an auxiliary spring, which will then allow us to return the BF keystone to nominal height.
    • While working on the BS, Enzo noticed that one of the stepper drivers was not responding. It turned out to be water damaged from the rain issues earlier in the year. Enzo and Fujii-kun opened the rest of the BS chassises on the second floor but they seem to be OK. Tanaka-san had made a third driver chassis as a spare, so we reserved that and will install it in the week of 12/10.
  • SRM
    • The SRM-W optic arrived and we installed it in place of the SRM-M in the metal mass, taking care to use 1.4 mm shims as recommended by Hirose-san. The weight of the new assembly was within 1 g of the old and did not disturb the height of the payload. There was a very small change in pitch which we corrected with the IM picos.
    • We installed the shelf for the OL receiver.
    • We added the arc weights and geophones and went through several rounds of improving the centering of the IP and then realigning the security structure back to vertical.
    • We calibrated the F0 LVDT, and checked the F0 and IP actuation signs.
    • We adjusted the SF trim masses to set the SF pitch and roll, did an inventory of the trim mass and set the damper gap.
    • We did a final alignment of the whole chain and left the suspension ready for TFs during the f2f week. There is only a few hours of work left before we can install and we hope to do that on Monday 12/10.
  • SR2
    • Enzo replaced the geophones and cables that had been borrowed for calibration and did several rounds of optimization of the IP frequency. He got as low as 46 mHz but with poor Q and so backed off a bit to 55 mHz and may back off a tiny bit more.
    • I derived updated IP matrices for the BS and SR, with more precise geometry data provided by Hirata-san, and published them as T1707205 and T1807663.
    • I created a CENTERING screen for the IP, with large panel meters for the LVDT signals and the derived L, T and Y signals.
    • Enzo confirmed that the fancy stepper control screen created by Shoda-san worked.
    • We installed a modified LPCD as IM-V for testing.
  • SR3
    • We moved HPCDs from BS and SR2 to replace the ones that had been stolen from SR3, so as to create a working suspension with an OL for Kozu-kun.

To-Do Lists, Schedule

Plan for week of 12/3

  • f2f Meeting at NAOJ - no Kamioka work.

Plan for week of 12/10

  • Crane SRM into tank.
  • Install new F0 yaw mechanisms on SRs.
  • Remove First Contact from SRM, unlock and realign.
  • Move SRM in-air cables over.

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