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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 and Fabian at Kamioka Mon-Thu. * Enzo and Hirata-san 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. ==== 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)]] |
==== 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. |
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| ==== Vacation/Visitor Info ==== * Terrence: 10/29-11/2 at Kamioka. |
==== 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. |
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.