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Size: 3633
Comment:
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Size: 797
Comment:
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| Deletions are marked like this. | Additions are marked like this. |
| Line 8: | Line 8: |
| * Hirata-san did an inventory of SR and other parts at Kamioka. * Mark and Enzo finalized the geometry matrices for the IP, entered them in MEDM and updated the safe.snap. * Mark, Enzo and Fabian worked with Izumi-san et al. to align the BS. We got the +Y beam fairly close to aligned (to the second gate valve, near IY). |
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| Line 9: | Line 12: |
| * Inspected LLB in tank - in a good position, but not very clean - apparent water spots and dirt. * Found the geophone adapter plates. * Retested SF FR stepper - still good. * Finally got SF LVDT working: * Found a short in the primary coil due to Al foil used for mechanical reinforcement at vacuum feedthrough connection. * Did a full calibration and found that linear range was too small (0.75 mm!) and did not cover nominal keystone height. * Decreased gain to increase linear range. * Adjusted the height of the yoke and secondary coil unit to center the linear region around the nominal keystone height. * Implemented velocity damping. * Found all parts for the LBB and damper rings. * Cu segments and some other parts were very dirty - wiped carefully for now, but should be properly cleaned before final install. * Outrigger parts for LBB have M16 thread cut directly into Al but should have had M16 helicoils. This is a galling risk with Ag-coated rod receptacles. Hirata-san organized rework. * Some special lock nuts are in short supply and are being borrowed from supply at ATC for next batch of BFs. * Made remaining two geophone in-air descrambler cables (total three). * Installed a thermometer supplied by Kokeyama-san on the tower around the BS tank. * Prepared the SF damper. * Designed a pattern of magnets for the two-segment arrangement of SF damper and laid it out on the magnet ring with the template. * Moved the Cu segments on SF cap by 30° (the cap had not been in the right position earlier). * Reinstalled PI: * Raised the PI with the crane and hooked the SF damper ring. Some of the rods did not fit the receptacles due to tolerance issue, but by going through a large number of rods and receptacles, we found three working sets. * Craned the PI onto the frame and suspended the SF/... section, this time with the hex cable clamp on the F0-SF rod. * Tensioned the PI yaw return spring, installed (but did not cable) the yaw stepper and adjusted the yaw of the SF/... section. We worry the return spring is not stiff enough. * Installed (but did not cable) the geophones. * Recentered the IP. The extra weight from the geophones (≈42 kg) and SF damper ring (≈17 kg) had brought the IP to near the point of instability, so we removed one arc weight (≈17 kg) and rearranged the other two in the top row to be symmetrical. * Added ballast to set the height of the F0 keystone. We now have about 6 kg in hand (due to removing one of the Cu segments for the SF damper). This should be enough margin for cables, temperature fluctuations etc. |
==== Plan for week of 10/30 ==== |
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| ==== Plan for coming weeks ==== For more detail, see [[KAGRA/Subgroups/VIS/TypeB/ToDo]]. |
Kamioka: Mark and Enzo * Continue alignment of BS. * Realign OL. * Work on servos. |
| Line 38: | Line 19: |
| Week of 5/29, 6/6: * Cabling: * Route BF/... cabling up past SF to PI. * Route SF cabling up to PI. * Add Type 3 extensions to SF/... cables. * Move vacuum flanges to positions on assembly frame more convenient for next stage (accessible from second floor, one on each corner of frame). * Move in-air cabling to match flange positions. * Cable and test PI vertical LVDT. * Calibrate PI vertical LVDT. * Set yoke on PI vertical LVDT (if necessary). * Cable and test PI yaw stepper. * Cable and test PI vertical stepper. * Cable and test PI horizontal steppers. * Cable and test PI horizontal LVDTs. * Calibrate PI horizontal LVDTs. * Crane into tank. |
Mitaka: Fabian and Hirata-san * SR procurement. * New PI GAS FR design. * BS LBB ballast mass design. * SR cable lamp design. |
Scraps of text for incorporation in the VIS Meeting Minutes
KAGRA/Subgroups/VIS/MeetingNAOJ
Type B (Mark)
Past week report
At Kamioka (Mark, Fabian, Enzo, Hirata-san):
- Hirata-san did an inventory of SR and other parts at Kamioka.
- Mark and Enzo finalized the geometry matrices for the IP, entered them in MEDM and updated the safe.snap.
- Mark, Enzo and Fabian worked with Izumi-san et al. to align the BS. We got the +Y beam fairly close to aligned (to the second gate valve, near IY).
Plan for week of 10/30
Kamioka: Mark and Enzo
- Continue alignment of BS.
- Realign OL.
- Work on servos.
Mitaka: Fabian and Hirata-san
- SR procurement.
- New PI GAS FR design.
- BS LBB ballast mass design.
- SR cable lamp design.