Differences between revisions 355 and 358 (spanning 3 versions)
Revision 355 as of 2018-12-14 13:46:15
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Editor: EnzoTapia
Comment:
Revision 358 as of 2018-12-21 11:40:45
Size: 4759
Editor: MarkBarton
Comment:
Deletions are marked like this. Additions are marked like this.
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==== Report for week of 12/10 ==== ==== Report for week of 12/17 ====
 * BS
  * Miyakawa-san worked on the BS real-time model and the gain/offset settings for the F0 LVDTINF block were lost, so we reentered them and did a new safe.snap file.
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  * We locked the suspension and craned it into the tank. This is the last Type B tank installation!
  * While inspecting the O-ring between the service ring and the lower section of the tank, Hirata-san found a small nick, so he replaced it. (This will hopefully be the last time that flange is closed, so it needs to be left ready for Mirapro to tighten.)
  * Hirata-san and Fabian removed the First Contact, but found that a tiny piece was left behind. With advice from Hirose-san, they managed to remove it via several rounds of dabbing with an acetone-soaked lens tissue.
  * They removed the IM-RM safety bar, unlocked the lower half of the suspension, and got it reasonably well aligned by eye.
  * They moved the vacuum feedthroughs and in-air cabling over, and reconnected nearly all the electronics. (The in-air cabling will need some tidying later, but
  * We unlocked the IP adjusted the level with the jacks to center it. As hoped, this also improved the alignment of the chain insecurity structure and fixed a touching issue.
  * Hirata-san installed and cabled the new F0 yaw stepper. We had allowed plenty of reserve mass, so there was no problem getting back to nominal height of the keystone. [''As of Thursday afternoon, it had not yet been tested - UPDATE?'']
  * We found that the Nikhef method Fabian had used to tune the F0 LVDT driver gave an artificially narrow working range, so he retuned it with Enzo's method and recalibrated the LVDT.
  * Fabian did a vertical position survey with all the GAS filters at nominal and found the height of the RM above the SS bottom plate was about 2.5 mm lower than in the CAD. This is about what we expected from a chain 7 mm longer than CAD and and F0 keystone set to 5 mm higher than CAD. In future we can survey to either the optic or the security structure as convenient, and we are in the range where we should easily be able to match the correct beam height with the jacks under the PI.
  * We got two OL viewports for SRM from Akutsu-san, and will install them sometime in January, whenever we have a free moment. Akutsu-san pre-torqued the inner ring of screws around the glass, so we only need to torque the outer bolts.
 * SR3
  * We also got a camera viewport for SR3 from Akutsu-san and will install it sometime in January.
  * Hirata-san installed and cabled the new F0 yaw stepper.
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  * Enzo worked on diagonalizing the IP and modeling of the whole suspension. He created Foton filters representing the response of the system in slots FM6-8 of the various filter banks.
  * Enzo and Mark set up the the SR2 OL. We may need to steal the LED back temporarily to do pitch setting on SRM, but we can take some interesting TFs on SR2 over the weekend.
 * SR3
  * Enzo configured a new stepper driver for SR3_IP and returned the one that had been borrowed from SRM. (The original SR3_IP had been used to replace a water-damaged unit on the BS.)
  * Enzo calibrated the SR2 OL. He noted that with the standard f=2500 mm collimator, the angular range was only about 100 µrad in pitch and 150 µrad in yaw, which is rather less than Enomoto-kun's preferred range of more like 400 µrad, so we borrowed f=1100 mm and f=3500 mm collimators to characterize. [''Enzo was going to do f=1100 mm and maybe f=3500 mm on Friday morning 12/21 - UPDATE?'']
  * Hirata-san installed and cabled the new F0 yaw stepper. We did not have enough reserve mass for SR2, so to save 300 g we had Mesco make a new, lighter top plate, and Hirata-san ultrasonically cleaned it. We were then able to get the desired F0 keystone height with about 200 g to spare.
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  * Mark got three more MPCDs (M = "medium" or "modified") from AEL and moved coil drivers around until all Type B suspensions had a driver in every position, with MPCDs for IM-H and HPCDs everywhere else. He returned the unused LPCDs.
  * Mark did an inventory of all the Type B electronics and got the various JGW Doc electronic items lists up to date - see [[https://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=7276|E1707276]]. This included opening all the LVDT drivers to check that they had the original cards - BS, SR3 and SRM did, but SR2 had both input cards new. We let AEL know.
  * Hirata-san helped Furuta-san with floor repair.
  * Fabian changed the PR3 thermometer battery.
  * Mirapro installed a bellows on the -Y side of SR3.
  * Enzo did a historical survey of the temperature as the various suspensions were being built and concluded that ideal operating temperature would be 25°C in the BS/SR2 area and 24°C for SR3/SRM.
  * Mark wrote a bash script to log all the GAS filter heights and LVDT actuation offsets, and an Excel spreadsheet to analyze the data to get an overview of the heights of the suspensions and the amount of height adjustment being used. He also reviewed old TF data to get near-DC values for the effect of GAS actuation on GAS height. This uncovered a few issues with calibration settings (such as for BS F0) having been lost because they hadn't been recorded in a safe.snap file, which we fixed.
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 * Most of team on holidays - no Kamioka work.  * Mark and Hirata-san on holidays, Enzo at Mitaka, Fabian.

==== Plan for week of 1/7 ====
 * Make sure BS is floating, recenter OL to capture current yaw position.
 * Vent BS.
 * Inspect BS F0 blades for cracks.
 * Install new BS F0 FR, and (if necessary) auxiliary CuBe spring.
 * Confirm geometry of LVDTs, geophones, FRs etc and update T1707205 if necessary.
 * Replace geophone preamps and cables (to fix noise, offset, pinout flip issues).
 * Add more mass to IP to get lower frequency.
 * Adjust all GAS filters to near mid-range (using keystone mass for F0 as much as possible, and FR+LVDT for SF and BF).
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 * Fabian: TBD but similar.
 * Enzo: TBD but similar.
 * Fabian: 12/31 - 1/4
 * Enzo: 12/31 - 1/4.
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 * Terrence: back at Kamioka from 1/7.

Scraps of text for incorporation in the VIS Meeting Minutes

KAGRA/Subgroups/VIS/MeetingNAOJ

Type B (Mark)

Report for week of 12/17

  • BS
    • Miyakawa-san worked on the BS real-time model and the gain/offset settings for the F0 LVDTINF block were lost, so we reentered them and did a new safe.snap file.
  • SRM
    • We unlocked the IP adjusted the level with the jacks to center it. As hoped, this also improved the alignment of the chain insecurity structure and fixed a touching issue.
    • Hirata-san installed and cabled the new F0 yaw stepper. We had allowed plenty of reserve mass, so there was no problem getting back to nominal height of the keystone. [As of Thursday afternoon, it had not yet been tested - UPDATE?]

    • We found that the Nikhef method Fabian had used to tune the F0 LVDT driver gave an artificially narrow working range, so he retuned it with Enzo's method and recalibrated the LVDT.
    • Fabian did a vertical position survey with all the GAS filters at nominal and found the height of the RM above the SS bottom plate was about 2.5 mm lower than in the CAD. This is about what we expected from a chain 7 mm longer than CAD and and F0 keystone set to 5 mm higher than CAD. In future we can survey to either the optic or the security structure as convenient, and we are in the range where we should easily be able to match the correct beam height with the jacks under the PI.
    • We got two OL viewports for SRM from Akutsu-san, and will install them sometime in January, whenever we have a free moment. Akutsu-san pre-torqued the inner ring of screws around the glass, so we only need to torque the outer bolts.
  • SR3
    • We also got a camera viewport for SR3 from Akutsu-san and will install it sometime in January.
    • Hirata-san installed and cabled the new F0 yaw stepper.
  • SR2
    • Enzo calibrated the SR2 OL. He noted that with the standard f=2500 mm collimator, the angular range was only about 100 µrad in pitch and 150 µrad in yaw, which is rather less than Enomoto-kun's preferred range of more like 400 µrad, so we borrowed f=1100 mm and f=3500 mm collimators to characterize. [Enzo was going to do f=1100 mm and maybe f=3500 mm on Friday morning 12/21 - UPDATE?]

    • Hirata-san installed and cabled the new F0 yaw stepper. We did not have enough reserve mass for SR2, so to save 300 g we had Mesco make a new, lighter top plate, and Hirata-san ultrasonically cleaned it. We were then able to get the desired F0 keystone height with about 200 g to spare.
  • Etc
    • Enzo did a historical survey of the temperature as the various suspensions were being built and concluded that ideal operating temperature would be 25°C in the BS/SR2 area and 24°C for SR3/SRM.
    • Mark wrote a bash script to log all the GAS filter heights and LVDT actuation offsets, and an Excel spreadsheet to analyze the data to get an overview of the heights of the suspensions and the amount of height adjustment being used. He also reviewed old TF data to get near-DC values for the effect of GAS actuation on GAS height. This uncovered a few issues with calibration settings (such as for BS F0) having been lost because they hadn't been recorded in a safe.snap file, which we fixed.

To-Do Lists, Schedule

Plan for week of 12/17

  • Final alignment of SRM payload, plus BF and SF GAS.
  • (Time permitting) unlocking/centering/tuning of IP.
  • Installation of Enomoto-kun's beam target on SRM (if available).
  • Installation/testing of F0 steppers on SR2, SR3, SRM, and (hopefully) final vertical height adjustment.
  • Installation of viewports on SRM.

Plan for week of 12/24

  • Mark and Hirata-san on holidays, Enzo at Mitaka, Fabian.

Plan for week of 1/7

  • Make sure BS is floating, recenter OL to capture current yaw position.
  • Vent BS.
  • Inspect BS F0 blades for cracks.
  • Install new BS F0 FR, and (if necessary) auxiliary CuBe spring.

  • Confirm geometry of LVDTs, geophones, FRs etc and update T1707205 if necessary.
  • Replace geophone preamps and cables (to fix noise, offset, pinout flip issues).
  • Add more mass to IP to get lower frequency.
  • Adjust all GAS filters to near mid-range (using keystone mass for F0 as much as possible, and FR+LVDT for SF and BF).

Vacation/Etc Info

  • Mark: 12/24 - 1/4.
  • Hirata-san: 12/24 - 1/4.
  • Fabian: 12/31 - 1/4
  • Enzo: 12/31 - 1/4.
  • Mark and Enzo: KAGRA International Workshop in Perugia, 2/14-16.
  • Terrence: back at Kamioka from 1/7.

KAGRA/Subgroups/VIS/TypeB/Minutes (last edited 2022-09-02 09:11:42 by fabian.arellano)