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==== Report for week of 10/15 ====
===== SRM =====
 * We received the fourth feedthrough we had been waiting for and installed it on the AF.
 * Fabian added the cables between the FE computer and the ADC/DAC boxes, and we checked that we were getting IO in the real-time model.
 * Fabian and Enzo connected up the Sat Amps.
 * Fabian double-checked the optic pitch, got the IRM nicely aligned to the IM, cabled IM OSEMs V1, V2, V3 and H1, and adjusted those OSEMs in/out to midrange.
 * Hirata-san set the compression on the F0 to 30 mm and measured the height and frequency as a function of load. He then fixed a loose screw on one of the blade tips and repeated the measurement. The frequency was fairly constant at around 0.5, which will do. He did a mass budget and chose a F1 CuBe spring. We may do a tiny bit more compression if the frequency degrades, and/or choose an even stronger spring if the load capacity is not enough.
 * Hirata-san took apart and reassembled one of the LBB blade units, which had a badly seated blade.
 * Hirata-san put cable clamps on the SF and on the PI. We are very short on the PEEK clamp pieces, so he scavenged some from SR2.
 * We added a new LAN hub for SRM, and configured two stepper drivers as SRM_IP and SRM_GAS.
 * Late in the week we received extra Type 3-4 cables (thanks to Sato-san for expediting) and were able to cable IM OSEMs H2 and H3, and the BF LVDT.
 * Enzo made a new batch of feedthrough adapters.
===== SR2 =====
 * We finalized the geophone cabling and reinstalled the geophones.
 * We received the new arc weights, and used some of them to install a basic allotment of 6 38-mm weights on SR3 per the CAD. We then added two extra 19-mm arc weights for tuning and got a good IP frequency of 0.133 Hz.
 * Apart from the F0 yaw stepper issue and the OL, the SR2 is now more-or-less complete and adjusted mechanically, and just needs software work (control loops etc). We will however have to borrow one of the geophones at some point to do a huddle test with the final batch of new geophones (including those for SRM). Terrence can set up the OL in the week of 10/29.
==== Plan for week of 10/22 ====
 * Friday is NAOJ Open Day Prep - no Kamioka work.
 * Mark, Hirata-san and Fabian at Kamioka Mon-Thu.
 * Enzo at Kamioka Tue-Thu.
===== SR2 =====
 * Do a measurement of how much torque is required on the F0 keystone to move the system in yaw. (This will help Sato-san choose a suitable stepper driver for the new design.)
 * Continue shakedown.
 * Gather parts for the OL (with help from Simon).
===== SRM =====
 * Scavenge HPCDs from SR2 and SR3 (currently we only have one for SRM) and organize to get LPCDs modified.
 * Suspend/weigh/balance the BF/... section.
 * Build up the AF and SS to the SF level.
 * Install the SF.
==== Plan for week of 10/29 ====
 * Mark, Enzo, Hirata-san, Fabian and Terrence at Kamioka Mon-Fri.
===== SR2 =====
 * Set up OL.
===== SRM =====
 * Continue assembly.
==== 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.
  * We took transfer functions for the IM. All of them look good except IM-T. We will inspect the payload next week in case anything is touching or rubbing.
  * Hirata-san opened the +X door of the vacuum chamber so we could inspect the payload, especially the OSEMs. We closed it back and covered with tape a small gap at the door.
 * 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 did f=1100 mm and will do f=3500 mm soon.
  * 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.
  * The day after installing the yaw stepper, we noticed the RM was touching the security structure but we were able to move it free by adjusting the cylinder with the spring and leaving the stepper motor in its nominal position. After this, for the other suspensions, we always checked the yaw of the payload immediately after installing the stepper.)
 * 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.
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==== Vacation/Visitor Info ====
 * Terrence: 10/29-11/2 at Kamioka.
==== 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.

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.
    • We took transfer functions for the IM. All of them look good except IM-T. We will inspect the payload next week in case anything is touching or rubbing.
    • Hirata-san opened the +X door of the vacuum chamber so we could inspect the payload, especially the OSEMs. We closed it back and covered with tape a small gap at the door.
  • 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 did f=1100 mm and will do f=3500 mm soon.
    • 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.
    • The day after installing the yaw stepper, we noticed the RM was touching the security structure but we were able to move it free by adjusting the cylinder with the spring and leaving the stepper motor in its nominal position. After this, for the other suspensions, we always checked the yaw of the payload immediately after installing the stepper.)
  • 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 2022-10-28 10:02:46 by fabian.arellano)