|
Size: 4362
Comment:
|
Size: 4136
Comment:
|
| Deletions are marked like this. | Additions are marked like this. |
| Line 2: | Line 2: |
| Line 5: | Line 4: |
| * Type B Past Week Summary * Mark and Fabian went to Kashiwa to clean up glue residue on the dummy BS and do a fit/function test of Tatsumi-san's modified tooling. * Most of the remaining glue came off with soaking in acetone, but there is still some in the machining grooves in the Al surface. Probably more work is required. * A set of cleanroom shoes borrowed from the ATC disintegrated when worn (the plastic had perished from age), which put small pieces of foam all over the floor in Hirose-san's cleanroom and required a lot of clean-up with a sticky roller! Cleanroom suits and shoes for use by Type B team at Mitaka/Kashiwa have been ordered, but will take another week to arrive. * The flag holding parts are now much easier to place and remove, much reducing the risk of breaking flags after gluing. * The sapphire and metal prisms from both the first BS gluing and the PR3 hanging test mirror were brought back to Mitaka for ultrasonic cleaning to remove glue, so they can be reused. * We arranged with Hirose-san to collect the dummy BS and mirror box next Thursday 8/4. (This is conditional on the new clean suits arriving.) Further work will be done at Mitaka. * Hirata-san arranged to borrow the NAOJ Hi-Ace van for the trip. * Hirata-san found the SR versions of the screws for immobilizing the IM and IRM. These fit much better than the BS ones (despite being the same design) and will be used for the BS. * Fabian updated the [[attachment:Geophone_Kamioka.png|geophone noise plot]] with a more accurate calibration and also plotted the [[attachment:Geophone_Kamioka_noise_ratio.png|S/N over readout noise]]. * Fabian identified 210 g of the 600 g deficiency in the IM mass as due to SS parts on the outside. However identifying the rest would require time-consuming disassembly of the IM, and it's not worth it because whatever the cause, the fix is to design and add more trim mass. * Hirata-san measured another filter, and worked on buying various small items. * Mark moved most of the contents of a bunch of older Dropbox and OneDrive shared folders into a new /Subsystems/VIS/TypeB folder on the KAGRA Dropbox. * Mark worked on a list of considerations for locating the BS rack, in preparation for discussions with Miyakawa-san et al. * Type B ongoing issues * OSEMs * Akutsu-san is working to get wide-mouth OSEMs ([[http://klog.icrr.u-tokyo.ac.jp/osl/?r=1853|2 assembled]]; first 4 expected to be assembled and washed by 8/8) * Longer cables for BF->PI and SF->PI. * Connectors RECEIVED, cables being made. * SR machining test NEARLY DONE. The part looks good and will be used but the ones for SR3 and SRM will be made from scratch. * Lower breadboard stuff * Installation to be incorporated into the procedure document. Mark/Takahashi to discuss. * Breadboard springs - RECEIVED. * Documents * BS Assembly Procedure [[http://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=4235| E1504235]], [[https://onedrive.live.com/redir?resid=D5CCFA70A378E0D0!195&authkey=!AM_usynuo9QI57g&ithint=folder,webloc|E1504235 draft]] * To-do list during Mark's vacation * Weigh IM/RM/IRM (Fabian, Hirata) - DONE but anomalies found. * Pack/ship IM/RM/IRM to Kamioka (Hirata/Fabian) - from 8/1. * Analyze geophone data (Fabian/Shoda) - data taken by Shoda-san; Fabian to find calibration factors. * Remove glue from dummy BS face (Fabian) - MOSTLY DONE. * Reglue flags and prisms (Tatsumi, Fabian) - from Friday 8/5. * Clean wire for BS and RM (Hirata) - DONE * Get new winch parts for new wire diameters - design received from Ikenoue-san * Do fit/function test of winches (Fabian/Hirata) * Ship winches to Kamioka (Hirata/Fabian) * Work on BS simulation (Fabian) * Do Inventor assembly for SR2 in chamber and on assembly frame (Hirata) - ONGOING. * Write more of payload assembly procedure (Fabian) * Write more of main assembly procedure (Mark) * Longer term to-do list * Do BS Simulink model (Mark, Kokeyama) * Do 2D drawings of SR2 parts (Hirata) * Redesign SRx IM wire clamps for larger prisms, remachined RMs. * Order SRM/PRM parts (Hirata/Shoda) * Order SRx fasteners (Hirata) |
=== Type B (Mark) === ==== Report for the week of 3/11 ==== * Fabian helped Fujii-kun with the PRM most of the week. Hirata-san also helped at various times. * Fabian monitored the SRM yaw drift. It gradually reversed but so far remained small. We will try resetting it to zero with the pico and see if the trend changes. * 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 TILT 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. He started on the LEN OL, but unfortunately the QPD stage fell and bent the brackets holding two of the micrometers. It's useable but we haven't installed it yet. * 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 procedure which allowed for it. Later we discovered that one of the 3 dB gain stages on the whitening filter was engaged, even though the switch on the BIO Config card was not. It mysteriously came good after we removed and replugged the card. * 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. |
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 helped Fujii-kun with the PRM most of the week. Hirata-san also helped at various times.
- Fabian monitored the SRM yaw drift. It gradually reversed but so far remained small. We will try resetting it to zero with the pico and see if the trend changes.
- 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 TILT 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. He started on the LEN OL, but unfortunately the QPD stage fell and bent the brackets holding two of the micrometers. It's useable but we haven't installed it yet.
- 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 procedure which allowed for it. Later we discovered that one of the 3 dB gain stages on the whitening filter was engaged, even though the switch on the BIO Config card was not. It mysteriously came good after we removed and replugged the card.
- 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.