|
Size: 3493
Comment:
|
Size: 3540
Comment:
|
| Deletions are marked like this. | Additions are marked like this. |
| Line 6: | Line 6: |
| ==== Report for week of 10/29 ==== | ==== 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. |
| Line 8: | Line 11: |
| * Enzo repaired some broken cables and made some long cables from shorter ones. We ultrasonically cleaned them at Toyama U, with help from Yamamoto-san. Enzo then reinforced the joins with EP30 (two cables) or heat shrink. * Hirata-san finished tuning the PI. It is now complete except for some PEEK cable clamp pieces which are expected next Monday. * Hirata-san wiped writing marks off the F0 and SF yoke magnets, and off the PI. * Hirata-san found we were running out of magnets and ordered more - we have almost enough (short by one) for the SF damper, but will need more for the LBB damper. * Fabian cabled and tested the BF cap picos. * Fabian routed all the cables up to the underside of the SF. He cabled and tested the SF LVDT and stepper. * We added the SF cap and weighed the SF/... section. We appear to have a good amount of load capacity margin. |
* 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. |
| Line 16: | Line 18: |
| * We opened the SR2 tank, borrowed a geophone for Fujii-kun's geophone test, and left the IP locked. * We gathered parts for the SR2 OL. We believe we have all the pieces we need except for an LED (the one originally allocated to SR2 is currently being used for pitch setting on SRM and we may need to steal it back). Akutsu-san wants to supervise us setting up the LED and receiver supports, so that will happen next week. |
* 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. |
| Line 19: | Line 24: |
| * Terrence visited for another week and made more measurements on the OL. A report is forthcoming. * BS * We searched for the dog clamps that we had borrowed from AOS to serve as ballast for the BS LBB and returned them to the AOS pallet. * Electronics * Enzo analyzed the LPCD and worked out the resistors we need to get the drive current recommended for the IM-V OSEMs by Shoda-san. |
* 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 29: | Line 30: |
| ==== Plan for week of 11/4 ==== * Mark, Enzo, Hirata-san and Fabian at Kamioka Mon-Fri. ===== SRM ===== * Main sequence * Add magnets to SF damper. * Install #353 poles * Move NB-03 jacks down. * Crane PI into AF. * Install F0-SF rod (#331) and flying saucer. * Route SF/... cables up to underside of F0. * Do vertical height budget. * Adjust SF trim mass for balance and keystone height. * Cable/test IP LVDTs. * Cable/test IP FRs. * LBB * Move KOACH filters * Put LBB damper rings in tank. * Set tank jacks to nominal height. |
|
| Line 48: | Line 31: |
| ==== Plan for week of 11/11 ==== * Mark, Enzo, Hirata-san and Fabian at Kamioka Mon-Fri. ===== SRM ===== * Unlock IP and center roughly. * Calibrate IP LVDTs. * Check/adjust alignment of SS. * Add arc weights and geophones (or extra mass equivalent to geophones). * Cable/test geophones. * Improve centering/tuning of IP and SS alignment. ==== Plan for week of 11/18 ==== * Friday 11/23 is Labor Thanksgiving Day. * Mark, Enzo, Hirata-san and Fabian at Kamioka Mon-Thu. ===== SRM ===== * Unlock IP and center roughly. * Calibrate IP LVDTs. * Check/adjust alignment of SS. * Add arc weights and geophones (or extra mass equivalent to geophones). * Cable/test geophones. * Improve centering/tuning of IP and SS alignment. * Crane into tank. |
==== 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.