Differences between revisions 307 and 309 (spanning 2 versions)
Revision 307 as of 2018-08-03 15:53:37
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Revision 309 as of 2018-08-08 10:49:23
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Editor: MarkBarton
Comment:
Deletions are marked like this. Additions are marked like this.
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 * We set up an OL outside the tank and checked the SR3 pitch - it was OK.
 * We ran power to the SR3 pico and stepper drivers and tested them.
 * We tried to offload a 700 µm discrepancy between the BF GAS zero position and the IM-V zero position but ended up scrambling the IRM-IM alignment, probably through sending a command to the wrong pico driver. We mostly fixed the BF/IRM pitch/roll, but we have some more work to do to fix the IM/RM/TM pitch/roll.
 * We debugged a problem with the SR2 alignment - the chain was offset by about 5 mm to +T, leading to fouling at the IM and RM levels. Some 2 mm of the offset was due to the F0 keystone being off center, apparently due to some combination of different-strength blades and the CuBe auxiliary spring, but the rest is a mystery.
 * We fixed a problem with the levelness of the PI due to the feet of the IP being set at uneven heights into the PI weldment, and it got the IP very closed to centered but it didn't fix the fouling problem.
 * We eventually fixed the fouling by setting the security structure at a slight angle so it remains slightly off at the SF level but is good at the bottom.
 * We installed the SR2 SF damper Cu segments and magnet ring.
 * Enzo and team debugged a malfunctioning bit in the SR3 IP BIO which turned out to be a defective 37-pin gender changer.
===== SR3 ======
 * We undid the accidental misalignment of the SR3. We also switched off the BF GAS offset we had been using, let the IM rise until near zero on the BF LVDT, and adjusted the IM vertical OSEMs back to mid-range.
 * We closed control loops for the SR3 GAS filters.
===== SR2 =====
 * We installed the SR2 SF damper magnet ring but found that the magnet pattern didn't match the Cu segments due to a different in the caps between SR3 and SR2. We raised the ring but left it suspended, clamped the template to the underside and rearranged the magnets.
 * We did a vertical height budget of the SR2. It turns out to have a very similar issue to the SR3: the chain is about 5 mm longer than the CAD, with about 3 mm of that between the SF and BF. We decided to do the same fix and operate with the F0 keystone 5 mm higher. We chose an total amount of ballast to give that keystone height and secured most of it to the SF, keeping a reserve for cables and the yaw stepper.
===== SRM =====
 * We moved the SRM assembly frame into its final position, reset it to the initial configuration, double-checked the heights of the crossbars, and lowered the optical table by 3 mm (to give margin for the optic to rise during hanging, which we had kept forgetting to do). We cleaned it up with the airgun and wet-wipes. We installed the IM ring and IM.
 * We assembled the SRM metal mass. Hirata-san made a jig from a plate with 4 screws which could safely hold the delicate front Sol-Black-coated ring upside down while the rest of the components were mounted on it.
 * We moved the metal mass to the mirror box and added the prisms and magnet standoffs.
Line 16: Line 18:
==== Plan for week of 8/6 ==== ==== Plan for week of 8/20 ====
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 * Kozu-kun works at Mozumi Mon, Fri, and Thu afternoon.  * Terrence and TBD at f2f on Friday 8/24.
* Kozu-kun works at Mozumi Mon, Fri.
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 * Tune IP.
Line 27: Line 31:
 * Do vertical height budget.
 * Choose F0 keystone height.
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 * Stage LBB damper rings in tank.
Line 35: Line 42:
 * Tune F0 for SRM.
 * Add LBB blade units, cable clamps etc.
 * Check PI coil connections, IP LVDT magnets.

Scraps of text for incorporation in the VIS Meeting Minutes

KAGRA/Subgroups/VIS/MeetingNAOJ

Type B (Mark)

Report for week of 7/30

===== SR3 ======

  • We undid the accidental misalignment of the SR3. We also switched off the BF GAS offset we had been using, let the IM rise until near zero on the BF LVDT, and adjusted the IM vertical OSEMs back to mid-range.
  • We closed control loops for the SR3 GAS filters.

SR2
  • We installed the SR2 SF damper magnet ring but found that the magnet pattern didn't match the Cu segments due to a different in the caps between SR3 and SR2. We raised the ring but left it suspended, clamped the template to the underside and rearranged the magnets.
  • We did a vertical height budget of the SR2. It turns out to have a very similar issue to the SR3: the chain is about 5 mm longer than the CAD, with about 3 mm of that between the SF and BF. We decided to do the same fix and operate with the F0 keystone 5 mm higher. We chose an total amount of ballast to give that keystone height and secured most of it to the SF, keeping a reserve for cables and the yaw stepper.

SRM
  • We moved the SRM assembly frame into its final position, reset it to the initial configuration, double-checked the heights of the crossbars, and lowered the optical table by 3 mm (to give margin for the optic to rise during hanging, which we had kept forgetting to do). We cleaned it up with the airgun and wet-wipes. We installed the IM ring and IM.
  • We assembled the SRM metal mass. Hirata-san made a jig from a plate with 4 screws which could safely hold the delicate front Sol-Black-coated ring upside down while the rest of the components were mounted on it.
  • We moved the metal mass to the mirror box and added the prisms and magnet standoffs.

Plan for week of 8/20

  • Mark, Enzo, Hirata-san, Fabian, Kozu-kun, Terrence, Panwei at Kamioka Mon-Fri.
  • Terrence and TBD at f2f on Friday 8/24.
  • Kozu-kun works at Mozumi Mon, Fri.

SR3
  • Finalize optic pitch, OSEM alignment.
  • Do TFs with temporary OL.
  • Install final OL.
  • Hook LBB, add ballast mass.
  • Tune IP.

SR2
  • Do vertical height budget.
  • Choose F0 keystone height.
  • Add estimated final ballast mass.
  • Do PI cable routing.
  • Adjust ballast/trim mass, with reserve for cables.
  • Stage LBB damper rings in tank.

SRM
  • Assemble metal mass.
  • Glue prisms, flags.
  • Reconfigure, align assembly frame.

To-Do Lists, Schedule

Vacation Info

  • Terrence: 8/24-26 f2f, then returns to Hong Kong.
  • Enzo: 9/14 JPS, 9/15 through 10/8 vacation in Chile.

KAGRA/Subgroups/VIS/TypeB/Minutes (last edited 2022-04-22 13:34:51 by fabian.arellano)