X1 insulation removal and cleanup is complete. The contractor will move to X2 on Monday. Work started on the 14th of Oct so the job has taken 9 work days.
We looked at Arnaud's TFs taken last night on SRM and determined that there was something unhealthy in the vertical/roll, pitch directions of motion as seen by the top BOSEMs (T1, T2, T3). Travis investigated and tweeked a few seemingly non-issues:
Slightly offcenter T2, possible loose cable connections (ha!), possibl droopy C3 cover at the top. A quick look at DTT roll and vertical and these don't seem to have helped... Arnaud is looking at verifying direction of excitation motion now.
Richard found that the binary cabling was pointing incorrectly. He recabled according to spec and actuation has restored to the BOSEMs we couldn't see actuation on previously. A look at a new roll DTT TF and things look healthier.
HOWEVER - Arnaud also pointed out that the side actuation has a sign flip somehwere. Travis dug into documentation and found that the side BOSEM is mounted on the incorrect side of the suspension. We'll switch it and retake the full TF set this weekend.
Side osem actuates in the right direction, so top mass actuation is now fully functionning. Phase 2b transfer functions will be running tonight.
In fact, the SRM is supposed to have the side BOSEM mounted opposite to most othere HSTS, with an appropriate sign flip in the side coil gain, functionality is as expected.
This now includes the 32 bit ODC library part and the IPC link to h1odcmaster.
This morning I noticed that the signals on 1 cable to the ITMx looked funny. Richard power cycled the AA chassis which didn't work, so I investigated the cabling at the satellite box. Indeed, the cable I suspected seemed easy to pop off the box, likely causing the glitching we had observed (although . I reseated it and then screwed in all connectors that were loose on all 5 ITMx sat box. Phew - that was an easy one. Currently, the ITMx filter text file is a mess so Arnaud is working on it.
Just checking to see how this awesome new feature works!
This is a test of the Logbook email. Please ignore.
The LVEA roof has a complete membrane as of yesterday. The crew has started on the next level down and should be onto the office area roof in a week's time.
Next week sheet metal trim should finish up on some of the out buildings.
Photos are the LVEA roof.
When creating a log entry users may now annotate it with optional tags. The main impact will be in the mail notices. When work (and log entries) involve multiple subjects and are appropriately tagged notices will go out based on the primary section/task + additional tags. For example if an entry was primarily about the FMP but had an impact (and was tagged for PSL) on PSL notifications would go out to people subscribed to FMP and PSL. The plan is to roll it out at LHO today and if everything goes well to update LLO sometime next week. As an example, this log entry is tagged with CDS.
Filiberto power cycled the TMSX coil drivers and the kHz lines are gone.
It's not clear if there's any difference between what Filiberto did today and what Aaron did yesterday, but this time it worked.
It looks noisy from 100 to 300Hz which we might have to investigate later.
- The data necessary for tilt decoupling has been taken using white noise excitation. Filtering and amplitude parameters have been defined in order to whiten the output signal and increase the SNR. Each transfer function can now be acquired in about 5 to 10 minutes, even during day time and purged air running (versus ~hours with our previous comb parameters). - The first picture shows the spectra of the input drive, and the corresponding output spectra during this white noise transfer function measurement. The input is the HEPI motion in the X direction driven at the controller error point. The RMS value of the drive is approximately 50 um. The time series show peaks around 150um. The output is the ISI inertial sensor response in the same direction. - The second plot shows the transfer function from the HEPI X motion drive to the ISI GS13 response. It also shows the response for the RY drive that is used to decouple as in a feed-forward scheme. The low frequency part of the two transfer functions is dominated by tilt coupling. The ratio of the two transfer functions at very low frequency is calculated and installed in the MEDM matrices to decouple X and RY. - The third plot shows the tilt coupling before correction, the expected decoupling and the measured decoupling. Results look good. We can start working on sensor correction tomorrow.
Side note: the transfer function amplitude below 1 Hz should be closer to 1. We need to check HEPI calibration.
Jeff K. recompiling h1susitmy, restarting h1susb123, restarting DAQ Oscillation on TMSX OSEMs observed, see Keita's alog Robert S. running magnetic injections on ITMY 09:15 Mitchel R. going into the LVEA to work on the cyropump baffle assembly between the X arm and H2 PSL enclosure 09:21 Gerardo M. joining Mitchel R. to work on the cyropump baffle assembly 09:30 Jim W. and Greg G. dropping down ISI cabling at ITMX 09:36 Jeff K. restarting h1ascimc 09:51 Richard M. and Peter K. going into the LVEA to look at HAM1, HAM2 Betsy W. running transfer functions on ETMX 10:08 Corey G. looking for alpha wipes in the LVEA 10:46 Driver for Praxair delivery to CP1 called notifying he was 15 minutes away 13:07 Mitchel R. heading back to the LVEA to work on the cyropump baffle assembly 13:20 Gerardo M. heading back to the LVEA to work on the cyropump baffle assembly 13:28 Ken working on conduit at end X, was at end Y 13:47 Hugh R. and Jim W. floating BSC3 on HEPI ~14:21 Lost and regained the midX FMCS channels, except for the pump status. Error reported on the FMCS server as well. 14:44 Stefan B. restarting h1odcmaster, h1odcy and h1odcx models 15:47 Hugh R. and Jim W. done at BSC3, Mitchel R. done at cyropump baffle assembly 16:01 DAQ restart
JimW GregG & HughR
We got all the actuators disconnected and reset for reinstallation. The HEPI is now unlocked and ready for IAS to again tell us where to go. Given that we pulled the system against the Actuators and have now disconnected them, it isn't surprising that we have rotated CW further. Based on the Dial Indicators our level is now out of spec by a few 0.1 mm and I predict we will need to move ~350urads CCW.
JimW GregG & HughR
We unlocked HEPI and suspended, well, you know, like everything on the HEPI DSCW Springs. While the horizontal position shifted we did put the verticals back close to where they started. Then we set up to look at the ISI Optical Table for level. We were level to +- 0.1mm so we did nothing further there. The vertical position is low by 1.8mm:
Nominal - GztoLz = position in local level - observed average = position error
D0901148 - T1100187
1661.7mm-2.8 = 1658.9 - 1657.1 = 1.8mm
Patrick told me that the TMS BOSEMs looked crazy in the morning, and I passed the information to Richard, who instructed Aaron to do something (power cycle the coil driver? I don't remember the details).
I came back to the control room at 4:30 PM and it's still crazy, showing 1727Hz peak and its harmonics. Looks quite similar to Arnaud's alog about BS BOSEMs (https://alog.ligo-wa.caltech.edu/aLOG/index.php?callRep=7237).
I'd like to know if Aaron actually did what was suggested.
Cable-pulling at Y End was completed. Screens were applied to the X Arm Spool cleanroom in the LVEA. Viewport materials were moved to Y Mid.
Don't know why or for how long this valve has been open
For future reference, usually our own. These are D1000225 extension cables.
(Arn, Kiss, Weavy, Trav)
Unfortunately, the ETMx TFs from last night returned all zero value data. SO, that needs fixing.
However, this morning we manually took all of the 6 DOF TFs on DTT and then hand compared all frequency peaks to the model. All peaks match the model frequencies to well within a few percent. SO, the ETMx is currently free and we should proceed with final ETMx HEPI and alignment work.
PDF below for all 6 main chain DOFs - cursors show a sample of peaks matching model frequencies.
Attached and for reference, are the trend of the calibrated osem signals for a week starting from wednesday oct 16th until thursday oct 24th
M0_DAMP and R0_DAMP are signals calibrated in urad and are representing relative motion between the structure (ISI) and the top mass suspensions. The largest shift over the week is 28 urad for M0 and 23 urad for R0
The other plots are individual osem signals, calibrated in um, representing the relative motion between the reaction and the main chain
The largest shift seen among those plots is at the lower left osem of the uim (L1_OSEMINF_LL) = 115um, which is clearly due to the reaction chain moving relatively to the ISI at the same time on Friday morning (see R0_DAMP).
M0 is the main chain R0 is the reaction chain L1 is the UIM L2 is the PUM, UL LL LR UR are upper left, lower left, lower right, and upper right osems
Further notes on Arnauds statement:
"...the lower left osem of the uim (L1_OSEMINF_LL) = 115um, which is clearly due to the reaction chain moving relatively to the ISI..."
could be clarified to
"...the lower left osem of the uim (L1_OSEMINF_LL) = 115um, which is a function of relative motion between the main and reaction chains, and the relative motion between the reaction chain and the ISI, and the possibility of a bumped flag in the process*. "
Specifically noteable is that none of the other 3 OSEMs on this same mass see this size of a motion which means that this signal is not representative of what the mass is actually doing in pitch/yaw. You cannot have only 1 OSEM signal change by a lot and assume that the mass pitches or yaws. 2-3 OSEMs must show motion that agrees.
*I am surmising that over the course of Thur/Fri HEPI adjustments (which are done 1 corner at a time), the ISI started out level, went unlevel corner by corner, and was restored to level by the time the 4th corner was finished. Possibly, during this unlevel time between corner 1 and 4 work, the ETMx suspension UIM LL magnet flag was close enough to get knocked around on the BOSEM a bit (likely because it started off not perfectly centered in range). When the level was restored, the flag snapped back into place, but a slightly different place relative to the LL BOSEM sensor - hence the observed larger 115um shift on just this OSEM.
Remember that this BOSEM senses relative motion between the main and reaction chain since the flag hangs on the main chain and the BOSEM hangs on the reaction chain. So, as Arnaud has discovered over the last few days of this investigation, quite difficult to use in diagnostics.
