|
Size: 2432
Comment:
|
Size: 3540
Comment:
|
| Deletions are marked like this. | Additions are marked like this. |
| Line 6: | Line 6: |
| ==== Report for week of 7/9 ==== * We cleaned up after the heavy rain. There was no significant damage but some cardboard boxes of parts got wet and the contents needed to be moved to other containers and the boxes discarded. Water collected on the SR2 crane slot cover and had to be vacuumed away before the cover could be opened. A new section of corrugated roof was installed to minimize the problem for the future. * Enzo and team got all of the in-vacuum and in-air cables for the SF/... and PI properly routed and tested except (so far) for the geophones. * Hirata-san and team finished tuning of the F0 for SR2 and moved the PI into the SR2 cleanbooth. It turns out to be about 8 kg weaker than for SR3, whereas the SR2 chain is only 3 kg lighter, so we will have to do some combination of decompression, removing Cu segments and using a stronger CuBe spring (e.g., a Type A F0 FR blade instead of the F2 one in SR3). We closed the floor in the SRM area for safety, but we will probably reopen it as soon as next week for the SRM F0 build. * Hirata-san opened the SR3 tank, craned the LBB damper ring sandwich up to the top of the tank and suspended it. * Enzo and team corrected a lot of flipped connections on the SR3 PI LVDTs (primary<->secondary on the horizontal, primary<->actuation on the F0). * We added the arc weights and geophones and re-centered the IP. It seems stable and very soft, which is good. ==== Plan for week of 7/9 ==== ==== Plan for week of 7/16 ==== * Monday 7/16 is Sea Day. * Mark, Enzo, Hirata-san, Kozu-kun, Terrence at Kamioka Tue-Fri. ===== Main Sequence ===== * Check/restore alignment of payload, especially optic pitch. * Testing, TFs. * Lock suspension. * Crane into tank. * Unlock suspension. * Rearrange cables. * Test. ===== F0/LBB Stuff ===== * Install correct IP in PI #2. * Crane PI #2 to second floor. * Rebuild top filter of PI #2. |
==== Report for week of 11/19 ==== * BS * Fabian did some debugging on the BS and found that the calibration for the F0 LVDT was off due to an Excel error, and that the sag wasn't quite the 7 mm originally observed, but still enough to cause the suspension to touch down. Enzo tried applying LVDT actuation at the GAS filters and got it to lift off far enough to get sensible TFs, but the required BF offset was enough to put the IM OSEMs at the very edge of their usable range, so this is not a good long-term solution. We can probably raise the F0 keystone during the vent by removing mass and/or installing an auxiliary spring, which will then allow us to return the BF keystone to nominal height. * While working on the BS, Enzo noticed that one of the stepper drivers was not responding. It turned out to be water damaged from the rain issues earlier in the year. Enzo and Fujii-kun opened the rest of the BS chassises on the second floor but they seem to be OK. Tanaka-san had made a third driver chassis as a spare, so we reserved that and will install it in the week of 12/10. * SRM * The SRM-W optic arrived and we installed it in place of the SRM-M in the metal mass, taking care to use 1.4 mm shims as recommended by Hirose-san. The weight of the new assembly was within 1 g of the old and did not disturb the height of the payload. There was a very small change in pitch which we corrected with the IM picos. * We installed the shelf for the OL receiver. * We added the arc weights and geophones and went through several rounds of improving the centering of the IP and then realigning the security structure back to vertical. * We calibrated the F0 LVDT, and checked the F0 and IP actuation signs. * We adjusted the SF trim masses to set the SF pitch and roll, did an inventory of the trim mass and set the damper gap. * We did a final alignment of the whole chain and left the suspension ready for TFs during the f2f week. There is only a few hours of work left before we can install and we hope to do that on Monday 12/10. * SR2 * Enzo replaced the geophones and cables that had been borrowed for calibration and did several rounds of optimization of the IP frequency. He got as low as 46 mHz but with poor Q and so backed off a bit to 55 mHz and may back off a tiny bit more. * I derived updated IP matrices for the BS and SR, with more precise geometry data provided by Hirata-san, and published them as T1707205 and T1807663. * I created a CENTERING screen for the IP, with large panel meters for the LVDT signals and the derived L, T and Y signals. * Enzo confirmed that the fancy stepper control screen created by Shoda-san worked. * We installed a modified LPCD as IM-V for testing. * SR3 * We moved HPCDs from BS and SR2 to replace the ones that had been stolen from SR3, so as to create a working suspension with an OL for Kozu-kun. |
| Line 37: | Line 30: |
| ==== Vacation Info ==== * Terrence: 8/24-26 f2f, then returns to Hong Kong. * Enzo: 9/14 JPS, 9/15 through 10/8 vacation in Chile. |
==== Plan for week of 12/3 ==== * f2f Meeting at NAOJ - no Kamioka work. ==== Plan for week of 12/10 ==== * Crane SRM into tank. * Install new F0 yaw mechanisms on SRs. * Remove First Contact from SRM, unlock and realign. * Move SRM in-air cables over. |
Scraps of text for incorporation in the VIS Meeting Minutes
KAGRA/Subgroups/VIS/MeetingNAOJ
Type B (Mark)
Report for week of 11/19
- BS
- Fabian did some debugging on the BS and found that the calibration for the F0 LVDT was off due to an Excel error, and that the sag wasn't quite the 7 mm originally observed, but still enough to cause the suspension to touch down. Enzo tried applying LVDT actuation at the GAS filters and got it to lift off far enough to get sensible TFs, but the required BF offset was enough to put the IM OSEMs at the very edge of their usable range, so this is not a good long-term solution. We can probably raise the F0 keystone during the vent by removing mass and/or installing an auxiliary spring, which will then allow us to return the BF keystone to nominal height.
- While working on the BS, Enzo noticed that one of the stepper drivers was not responding. It turned out to be water damaged from the rain issues earlier in the year. Enzo and Fujii-kun opened the rest of the BS chassises on the second floor but they seem to be OK. Tanaka-san had made a third driver chassis as a spare, so we reserved that and will install it in the week of 12/10.
- SRM
- The SRM-W optic arrived and we installed it in place of the SRM-M in the metal mass, taking care to use 1.4 mm shims as recommended by Hirose-san. The weight of the new assembly was within 1 g of the old and did not disturb the height of the payload. There was a very small change in pitch which we corrected with the IM picos.
- We installed the shelf for the OL receiver.
- We added the arc weights and geophones and went through several rounds of improving the centering of the IP and then realigning the security structure back to vertical.
- We calibrated the F0 LVDT, and checked the F0 and IP actuation signs.
- We adjusted the SF trim masses to set the SF pitch and roll, did an inventory of the trim mass and set the damper gap.
- We did a final alignment of the whole chain and left the suspension ready for TFs during the f2f week. There is only a few hours of work left before we can install and we hope to do that on Monday 12/10.
- SR2
- Enzo replaced the geophones and cables that had been borrowed for calibration and did several rounds of optimization of the IP frequency. He got as low as 46 mHz but with poor Q and so backed off a bit to 55 mHz and may back off a tiny bit more.
- I derived updated IP matrices for the BS and SR, with more precise geometry data provided by Hirata-san, and published them as T1707205 and T1807663.
- I created a CENTERING screen for the IP, with large panel meters for the LVDT signals and the derived L, T and Y signals.
- Enzo confirmed that the fancy stepper control screen created by Shoda-san worked.
- We installed a modified LPCD as IM-V for testing.
- SR3
- We moved HPCDs from BS and SR2 to replace the ones that had been stolen from SR3, so as to create a working suspension with an OL for Kozu-kun.
To-Do Lists, Schedule
Plan for week of 12/3
- f2f Meeting at NAOJ - no Kamioka work.
Plan for week of 12/10
- Crane SRM into tank.
- Install new F0 yaw mechanisms on SRs.
- Remove First Contact from SRM, unlock and realign.
- Move SRM in-air cables over.