Differences between revisions 344 and 402 (spanning 58 versions)
Revision 344 as of 2018-11-09 09:50:41
Size: 3734
Editor: MarkBarton
Comment:
Revision 402 as of 2019-03-14 19:08:46
Size: 3649
Editor: MarkBarton
Comment:
Deletions are marked like this. Additions are marked like this.
Line 2: Line 2:
Line 6: Line 5:
==== Report for week of 10/29 ====
 * SRM
  * Enzo realized that he could cover the next round of needed cables with more cable soldering and did another batch. Because Yamamoto-san's lab was running low on isopropanol, Hirata-san washed them with ethanol at Mozumi.
  * Enzo worked out the optimum output resistance for the LPCDs to substitute for HPCDs with the horizontal IM OSEMs. The value was quite close to that already chosen for modified LPCDs by the cryogenic group, so we're going to standardize. The modified LPCDs will have to be operated with the internal watchdog disabled for now because it was hard-wired to 2 mA.
  * Fabian finished adding the TM OSEM cables out to the rack and tested them.
  * We ran DC power and network to the second SRM stepper driver. We still need to get one more DC power cable to replace one we borrowed from SR3. We added the remaining steppers to the Python driver and MEDM screen.
  * We reconfigured the top of the assembly frame in preparation for the PI (removing crossbars and moving jacks down).
  * Hirata-san put the magnets on the SF damper and we hooked it to the PI, craned the PI into the assembly frame and joined it to the security structure.
  * We installed the F0-SF rod and flying saucer and suspended the SF/... section. We had plenty of spare load capacity, so we changed the CuBe spring to a weaker one and put 2.3 kg of ballast on the SF cap. This leaves 1.2 kg reserve for cables and an F0 yaw stepper mechanism.
  * We reduced the trim mass on the BF to compensate for the mass of the TM OSEM cables.
  * We measured all the bounce frequencies.
  * Hirata-san put magnets on the LBB damper magnet ring, put the pieces into the tank and assembled them into a sandwich ready for craning.
 * SR2
  * Hirata-san unclamped the LBB damper rings and suspended the LBB. It still needs ballast mass and is currently sitting high, with the blades at their upper stops.
==== Report for the week of 3/11 ====
 * Fabian mostly helped Fujii-kun with the PRM.
 * Fabian monitored the SRM yaw drift. It gradually reversed but so far remained small.
 * Mark and Hirata-san debugged the BS:
  * We inspected the payload section and quickly found the problem: two RM EQ stops were touching, on the +L (-X,+Y) side at the top. This was probably because the stops had been adjusted with the IP unlocked and sitting a few mm to -L, whereas now we have the DCCTRL running and have been locking the IP at the LVDT zero. We drove the IP to L=+1.5 mm as a near-worst case, and backed off all the stops to give several mm of margin. Then we zeroed the IP pitch, roll and yaw with the picos.
  * We also opened the top of the BS and confirmed that the mechanical zero defined by the locking mechanism agreed with the LVDT zero. It was very close in L and T, but -728 µrad in Y, driven mostly by a -805 µm offset in H3. That much is probably not a dumb error but just a difference in technique among the three people using calipers to take data for the calibration.
  * We then prepared the BS for close-up:
   * We wiped and inspected the O-ring for the lid and replaced the lid.
   * We wiped all accessible surfaces in the lower half of the tank, rescued some dropped items (some PEEK tube and a small nut) and un-immobilized the LBB.
  * After all the above, the OL was a bit off-center but still on the QPD, and Nagano-san fairly quickly recovered the original alignment.
 * Terrence rebuilt the BS OL according to a new layout suggested by Simon, which avoids scrambling the pitch/yaw at the first steering mirror and greatly reduces the amount of diagonalization required.
 * Terrence noticed some anomalous cross coupling on the SR2 (but not the SR3) and we investigated.
  * We suspected it might be an odd position of the beam spot on the optic, so we took pictures through the camera and LED viewports of SR3, and opened the SR2 tank and used a white target, but the beam spots were in very similar positions - close to central vertically and about 3 cm to the left of center horizontally.
  * We suspected it might be something touching at the IRM (because the IM OSEM TFs were fine), so we checked using a stick mirror with the IP centered, but all EQ stops were well backed off.
  * We suspected it might be a ghost beam from the LEN/TILT beamsplitter (and one was clearly visible on the SR2 TILT QPD) so Terrence set up a beam block, which improved things slightly but not completely.
  * Finally Terrence discovered that the problem was mainly uneven sensitivities of the QPD quadrants, and devised a new calibration and diagonalization procedure which allowed for it.
 * Enzo and Terrence did a health check of the SRM and it was fine except for some apparent electrical noise around 240 Hz. They put in a notch filter to get rid of it for now.
Line 21: Line 23:
  ==== To-Do Lists, Schedule ====
 * [[KAGRA/Subgroups/VIS/TypeB/ToDoBS]]
 * [[KAGRA/Subgroups/VIS/TypeB/ToDoSR]]
 * [[https://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=7779|JGW-L1807779 Type B Schedule (SR)]]
==== Plan for week of 3/18 ====
 * Mark, Fabian, Terrence at Kamioka full week.
 * More OL stuff.
 * SRM controls and Guardian.
 * Reset SRM yaw and continue monitoring yaw drift.
 * Assist with pump down.
 * Work on Type B paper.
 * Tidy up.
  * Throw out foil and other garbage.
  * Gather and clean tools.
  * Gather and organize unused parts and fasteners.
  * Pull out unused cables in cable tray near SR3.
  * Return all unused cables to tent.
  * Tidy up cables in rear of SR2 rack.
  *
Line 27: Line 39:
==== Plan for week of 11/4 ====
 * Mark, Enzo, Hirata-san and Fabian at Kamioka Mon-Fri.
===== SRM =====
 * Main sequence
  * Add magnets to SF damper.
  * Install #353 poles
  * Move NB-03 jacks down.
  * Crane PI into AF.
  * Install F0-SF rod (#331) and flying saucer.
  * Route SF/... cables up to underside of F0.
  * Do vertical height budget.
  * Adjust SF trim mass for balance and keystone height.
  * Cable/test IP LVDTs.
  * Cable/test IP FRs.
 * LBB
  * Move KOACH filters
  * Put LBB damper rings in tank.
  * Set tank jacks to nominal height.
Line 46: Line 40:
==== Plan for week of 11/11 ====
 * Mark, Enzo, Hirata-san and Fabian at Kamioka Mon-Fri.
===== SRM =====
 * Unlock IP and center roughly.
 * Calibrate IP LVDTs.
 * Check/adjust alignment of SS.
 * Add arc weights and geophones (or extra mass equivalent to geophones).
 * Cable/test geophones.
 * Improve centering/tuning of IP and SS alignment.
Line 56: Line 41:
==== Plan for week of 11/18 ====
 * Friday 11/23 is Labor Thanksgiving Day.
 * Mark, Enzo, Hirata-san and Fabian at Kamioka Mon-Thu.
===== SRM =====
 * Unlock IP and center roughly.
 * Calibrate IP LVDTs.
 * Check/adjust alignment of SS.
 * Add arc weights and geophones (or extra mass equivalent to geophones).
 * Cable/test geophones.
 * Improve centering/tuning of IP and SS alignment.
 * Crane into tank.

==== Vacation Info ====
 * Hirata-san at Mitaka, Mon 11/19.
==== Vacation/Travel Info ====
 * Enzo at JPS then final vacation, 3/13-29
 * Terrence's last day, 3/29.

Scraps of text for incorporation in the VIS Meeting Minutes

KAGRA/Subgroups/VIS/MeetingNAOJ

Type B (Mark)

Report for the week of 3/11

  • Fabian mostly helped Fujii-kun with the PRM.
  • Fabian monitored the SRM yaw drift. It gradually reversed but so far remained small.
  • Mark and Hirata-san debugged the BS:
    • We inspected the payload section and quickly found the problem: two RM EQ stops were touching, on the +L (-X,+Y) side at the top. This was probably because the stops had been adjusted with the IP unlocked and sitting a few mm to -L, whereas now we have the DCCTRL running and have been locking the IP at the LVDT zero. We drove the IP to L=+1.5 mm as a near-worst case, and backed off all the stops to give several mm of margin. Then we zeroed the IP pitch, roll and yaw with the picos.
    • We also opened the top of the BS and confirmed that the mechanical zero defined by the locking mechanism agreed with the LVDT zero. It was very close in L and T, but -728 µrad in Y, driven mostly by a -805 µm offset in H3. That much is probably not a dumb error but just a difference in technique among the three people using calipers to take data for the calibration.
    • We then prepared the BS for close-up:
      • We wiped and inspected the O-ring for the lid and replaced the lid.
      • We wiped all accessible surfaces in the lower half of the tank, rescued some dropped items (some PEEK tube and a small nut) and un-immobilized the LBB.
    • After all the above, the OL was a bit off-center but still on the QPD, and Nagano-san fairly quickly recovered the original alignment.
  • Terrence rebuilt the BS OL according to a new layout suggested by Simon, which avoids scrambling the pitch/yaw at the first steering mirror and greatly reduces the amount of diagonalization required.
  • Terrence noticed some anomalous cross coupling on the SR2 (but not the SR3) and we investigated.
    • We suspected it might be an odd position of the beam spot on the optic, so we took pictures through the camera and LED viewports of SR3, and opened the SR2 tank and used a white target, but the beam spots were in very similar positions - close to central vertically and about 3 cm to the left of center horizontally.
    • We suspected it might be something touching at the IRM (because the IM OSEM TFs were fine), so we checked using a stick mirror with the IP centered, but all EQ stops were well backed off.
    • We suspected it might be a ghost beam from the LEN/TILT beamsplitter (and one was clearly visible on the SR2 TILT QPD) so Terrence set up a beam block, which improved things slightly but not completely.
    • Finally Terrence discovered that the problem was mainly uneven sensitivities of the QPD quadrants, and devised a new calibration and diagonalization procedure which allowed for it.
  • Enzo and Terrence did a health check of the SRM and it was fine except for some apparent electrical noise around 240 Hz. They put in a notch filter to get rid of it for now.

Plan for week of 3/18

  • Mark, Fabian, Terrence at Kamioka full week.
  • More OL stuff.
  • SRM controls and Guardian.
  • Reset SRM yaw and continue monitoring yaw drift.
  • Assist with pump down.
  • Work on Type B paper.
  • Tidy up.
    • Throw out foil and other garbage.
    • Gather and clean tools.
    • Gather and organize unused parts and fasteners.
    • Pull out unused cables in cable tray near SR3.
    • Return all unused cables to tent.
    • Tidy up cables in rear of SR2 rack.

Vacation/Travel Info

  • Enzo at JPS then final vacation, 3/13-29
  • Terrence's last day, 3/29.

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