Fabrice and Dave:
We successfully made a new h1isiitmy model using the latest isi2stagemaster model changes. We restarted h1isiitmy with the new code
Chris, Sheila, Dave:
I found that I had mistakenly restarted an incorrect h1asc model on Tuesday. After the first DAQ restart that day I noticed that the DAQ picked up a newer INI fle for h1asc and I assumed (which we should never do) that the last "make install" was correct. It appears that later changes were not installed.
I did a clean "make" and "make install" on h1asc and restarted the model.
Dave:
Finally I did a DAQ restart to support the above changes (remembering to wait into the next 10min period to flush out the second trends)
Here is the restart sequence in detail:
2014_05_15 13:16 h1isiitmy
2014_05_15 13:19 h1asc
2014_05_15 13:22 h1broadcast0
2014_05_15 13:22 h1dc0
2014_05_15 13:22 h1fw0
2014_05_15 13:22 h1fw1
2014_05_15 13:22 h1nds0
8:15-8:30 Fred, Richard, Cyrus, Filiberto, Aaron, Bubba, Gerardo, Jeff B, Bubba, Travis, Hugh, Mitchell, Justin, Mike, Thomas, Jeff K, Fabrice, Alexa, Steban, Robert, Jamie, etc. • SRM alignment on HAM5 - (Jeff B/Jason) • TCS tables work continues. – (David, Thomas) • Getting things ready to transport the OFI - (Gerardo) • Craning activity in LVEA / Moving clearoom from west bay -(Apollo) • ICS rack inventory in LVEA – (Richard/Filiberto) • Commissioning work continues (Commissioners) • Testing and assembly operations continue in Staging building –(Jim/Hugh/Scott) • Guardian work in progress -(Jamie) LVEA is Laser SAFE
Richard warned me that the Fiber polarization had probably drifted at EY due to some work done around the table. Indeed it had drifted to up to 33% for the wrong polarization. However, Stefan had increased the threshold to 36. I returned the threshold down to 30 and adjusted the controller. I also had to adjust the EX polarization when I turned the controller on, which forced both polarizations to drift. All is good now.
Craning activity in the LVEA at the moment. A cleanroom is being moved - Apollo
model restarts logged for Wed 14/May/2014
2014_05_14 12:37 h1fw1
unexpected restart of h1fw1
Kiwamu, Stefan, Both ALS_DIFF and ALS_COMM were straight forward today, and we got them locked literally in minutes. I.e. the ESD is still working fine. We misaligned the arms, and verified that 3f locking works just fine without the arms. We locked the arms and parked them 1kHz off resonance. I this configuration the the RF27_I signal worked fine, but the REFL27_Q signal had significant contamination from the COMM noise at 70Hzish (periscope peak). Thus we designed a broad notch filter in the mich loop, which kept the BS from saturating. However it seems that MICH is still too strongly contaminated by the low frequency COMM noise. As a result the MICH loop seems to drift out of its linear range. Ideas: - divide REFL27_Q by POP_18 to expand the linear range - rephrase REFL27 to reduce the coupling Either way, an earthquake told us to get some sleep.
David H, Greg G, Thomas V - Corner Hartmann table now has the Y-arm in-air optics mounted and positioned, ready for alignment using the visible laser. Components for the HWS were tracked down and staged. - TCSX CO2 laser continued to run all day. Once going to laser hazard we realigned the CO2 beam that is transmitted through the output beam splitter. This transmitted beam passes through another 50/50 beam splitter, with the (second) transmitted beam aligned to the output power meter, while the reflected beam was expanded and aligned to the FLIR camera screen position. This required the repositioning of some cables and mounts located near the CO2 laser and RF driver. TSCX laser will continue to run overnight. Rotation stage set to 44 degrees (with interlock cable removed to prevent changes to this angle). Table doors are locked. TSCY chiller and power supplies continue to run, TCSY laser is turned off.
Richard showed me that there is a liner coupling from any of the electrodes to the OPLEV even when there's no bias anywhere, and the bias-less coupling is on the same order as the coupling with bias.
I started flipping the bias of the common ("DC") electrode while keeping all four quadrants at zero count output, and indeed there's a linear coupling, and the effect is not subtle.
In the attached, I changed the DC bias from 125000 to 0 to -125000, then to 0 and finally back to +125000. The ETM points up by 0.3urad in the first step, then further up 0.5urad in the second step (instead of going back to the original position). It's 0.8 urad peak to peak!
OTOH, when I set the four quadrants such that top two outputs -50900 counts and the bottom +50900 to tilt the optic legitimately while the DC bias is kept at 125000 counts, I can only move it by -0.5 urad peak to peak (second attachment).
This could still be electronics offset, so I looked at the ESD readback. The readback is not calibrated, but four quadrants always read from -75 to -200 counts when I'm outputing zero, the 300volt-ish thing reads 30000-ish counts, so the voltage offset for the quadrants should be 2V-ish at most. That's not large enough, I think.
I disconnected the ESD drive cables between the current limiting resistor and the flange. Put large drive signals on the cables and did not see a response in the oplev. So it is not a direct coupling in the rack or cables up to the chamber.
At LASTI we saw static charges on the test mass high enough to mimic a bias voltage of 125 V (very large!). John Miller put together a procedure and MATLAB script for measuring what this effective bias was. So the problems you are seeing with a non-symmetric response are within the limits of what has been observed before. See the LASTI ilog http://emvogil-3.mit.edu/ilog/pub/ilog.cgi?group=lasti&task=view&date_to_view=12/18/2009&anchor_to_scroll_to=2009:12:18:16:36:37-brett u: reader p: readonly This script happens to be on the svn at /ligo/svncommon/SusSVN/sus/trunk/QUAD/Common/MatlabTools/ChargeScript It will need some modification to work at the sites, since it was written to work in the old LASTI file structure. Basically though, it automatically runs DTT from MATLAB, and measures the response at 11 Hz with a range of bias voltages. Note, Rai has put together a gizmo to discharge the test masses with ionized nitrogen. Not sure of its status. Venting to some torr might also help, not sure.
The discharging rig Brett is referring to is described in LIGO T1100332. It currently resides at MIT under clean conditions. It and the associated electronics can be shipped to LHO. It needs a 2 3/4 inch conflat gatevalve attached to one of the ten inch blank flanges on the BSC chamber at the charged mirror height. The gas injected into the deionizer needs to be clean nitrogen such as the boil off from liquid nitrogen passed through another liquid nitrogen trap and warmed to room temperature before injection into the BSC. RW
J. Kissel, for F. Clara, and R. McCarthy After investigating further, Richard and Filiberto found that source of failure in the chassis was the mysterious loss of the +18 V power supply to the ESD driver chassis between rack power strip and the the back of the chassis. This was confirmed after disconnecting, to find the positive leg without continuity. However, after "pulling the cable apart" to find the source of the discontinuity, he was not able to reproduce it. After reassembling the cable, and restoring the connection, the driver came alive again. Further vigorous attempts to recreate the disconnect were unsuccessful. It appears the gremlins inside the driver chassis are creeping there way out to the power supply. This 18V power cable came with the ESD driver from Strathclyde, so Richard plans to replace it with one commercially made in house. As soon as I get the arm from fellow commissioners trying to finish gathering data for her thesis, I'll try to grab the data I'd originally set out to get this morning.
While working on EX suspension, I realized the yaw motion was big on the oplev, so I tried switching the Rz blends on the ISI to see what's a good config. Moving the Rz blends of both stages from Tcrappy to Start seem to have helped (~0.6urad peak to peak -> ~0.2urad). Green curve in attached plot is the oplev yaw signal (urad)
Day's Activities
J. Kissel, for K. Izumi, S. Ballmer, and S. Dwyer One of the tricks to get ALS DIFF working without saturation was to tweak the distribution filter design. I attach a comparison between the filters installed on 2014-05-08 vs. those tweaked last night (2014-05-14). Only two small changes: (1) To the UIM-TST LP, whose composition included (a) two poles at 6 [Hz], three poles at 150 [Hz] (b) elliptic filter of (freq,order,ripple,stopDB,zQ) = (9, 3, 1, 20, 1.4) (c) elliptic filter of (freq,order,ripple,stopDB,zQ) = (19, 3, 1, 20, 1.4), now has the second elliptic filter's corner frequency much lower, at 6 [Hz], i.e. a new (c) of (c) elliptic filter of (freq,order,ripple,stopDB,zQ) = (6, 3, 1, 20, 1.4), (2) To the TST-UIM HP, whose composition included (a) (1 - UIM-TST LP) (b) an elliptic high-pass of (freq,order,ripple,stopDB,zQ) = (.7, 2, 1, 10, 3) now has an additional high-pass filter, (c) two zeros at 0 [Hz], two poles at 0.2 [Hz], normalized to unity at high frequency, i.e. zpk([0;0],[0.2;0.2],1,"n")gain(25) Note that this extra low-pass has been installed, ignoring its affect on the complementarity with the UIM-TST LP. This needs to be fixed if we desire complementarity. These tweaks served to (1) to move the elliptic filter's gain peaking bump out of the way of the 10 [Hz] features in the input noise, and (2) roll off the low-frequency end of the test mass drive faster. ------------- Details The New H1 SUS ETMX Filter Configuration: H1:SUS-ETMX_M0_LOCK_L (same as before) FM1 "invL2L1" (part one of plant inversion filter) FM2 "invL2L2" (part two of plant inversion filter) FM3 "top/tst" (gain only filter to compensate for the gain ratio) FM5 "blendLP" H1:SUS-ETMX_L1_LOCK_L FM6 "invL2LNEW" (part one of plant inversion filter) FM7 "patch" (part two of plant inversion filter) FM8 "LISOfit" (part three of plant inversion filter) FM9 "uim/tst" (gain only filter to compensate for the gain ratio) FM3 "blendHP" (UIM-TOP HP complement) FM4 "blendLP-2" (UIM-TST LP complement, with lower frequency elliptic filter) H1:SUS-ETMX_L3_LOCK_L FM6 "MatchedinvL2L" (part one of plant inversion filter) FM7 "patch" (part two of plant inversion filter) FM4 "blendHP-M0" (TST-TOP HP complement) FM5 "blendHP-L1_2" (TST-UIM HP complement) FM9 "hp.2" (extra high-pass for TST-UIM HP complement) In order to create these modifications to the UIM-TST LP, Kiwamu grabbed my design script from /ligo/svncommon/SusSVN/sus/trunk/QUAD/Common/FilterDesign/HierarchicalControl/DARMmodel_ALS_20140428.m copied it to his home directory, /ligo/home/kiwamu.izumi/ to play around, /ligo/home/kiwamu.izumi/Desktop/farm/matlab/ modified the filters mentioned above, and then used a fancy new script, /ligo/home/kiwamu.izumi/Desktop/farm/matlab/fofon.m which takes in a continuous zpk filter, and produces a foton design string to be copied and pasted into Foton. If the filter is a high-pass, the only other step is to use the "Gain" field to set the gain to be unity at high-frequency. The modification to the TST-UIM HP was done later in the evening after I'd left, but by the simplicity of its design, I think it was just added directly without testing any stability or complementarity in Matlab prior to install. [[elliptic filters are generated using ${SeiSVN}/seismic/Common/MatlabTools/myellip_z2.m]] [[hp elliptic filter is generated by ${SeiSVN}/seismic/Common/MatlabTools/myhpellip_z.m]]
Andres R., Margot P., & Jeff B. We installed H1-SRM into HAM5 today. The installation went smoothly. Will start on alignment work in the morning.
Betsy, Mitchell, Margot, Myself
Today we finished assembly of the ACB suspension and mounted both the suspension and the baffle box to the test stand. We will continue adding the last few remaining bits to the assembly and proceed with suspending and balancing tomorrow.
Because of physical restriction on the TMS ISC table real estate, pico mirrors for IR QPDs (M4 and M14) are mostly degenerate, i.e. if you rotate one mirror the beam position on both of the QPDs change by similar amount in the same direction.
Using nominal QPD sled parameters and as-built TMSY parameters (that is not that different from TMSX),
QPDA position shift = [3.2105, 3.1256] * [M4 rotation, M14 rotation]'
QPDB position shift = [4.8555, 4.9264] * [M4 rotation, M14 rotation]'
where [A B]' means a column vector. As you can see this is mostly degenerate.
For example, to keep the beam position on QPDA fixed while moving QPDB position down by 1mm, you PIT down M14 by about 5.0 mrad and then PIT up M4 by about 4.9mrad:
To bring QPDB down by 1mm... | QPDA pos | QPDB pos | Beam position on M14 | Beam position on HPBD | Beam position on viewport |
M4 up by 4.883 mrad | 15.7mm up | 23.7mm up | 5.2mm up | 7.4mm up | 20mm up |
M14 down by 5.016 mrad | 15.7mm down | 24.7mm down | Not affected | Not affected | Not affected |
Total | no change | 1mm down | 5.2mm up | 7.4mm up | 20mm up |
QPD diameter is 3mm, so as far as we see the beam on one QPD when the other is centered and the beam is not close to the edge of the clear aperture for viewport-TMS path, it should be possible to center both without losing the beam on ISCT.
I think that's the case for Y, but it's not clear if that was the case for X at some stage.
I used the following parameters from T1000247:
Lens1, focal length 333mm, z=0, Lens2, focal length -111mm, z=240mm.
QPDA, z=650mm, QPDB, z=950mm
I eyeballed the following parameters from D1000484:
M4 to M14: about 21"
M14 to Lens1: about 2"
M4 to high power beam dump: about 30"
M4 to M13 (the last steering mirror that stees the beam to the ISCTEX): about 23"
I used the following parameters from D0902168:
M13 to the viewport, horizontal distance 1.371m, declination angle about 20 degrees.
Since both end stations are closed up, I increased the alarm levels for both of these monitors to 600cts (MINOR) & 800cts (MAJOR) for 0.3 & 0.5um (they had been set at 100 & 200 cts, respectively).
I think that the ISI trip happened before the suspension trip, this was while we were locking diff. I also thought that the T240s were green before I untripped the watchdog, but maybe they weren't because the ISI tripped again as it was isolating.
I stongly suspect that the second trip is due to the bug Fabrice and I noticed in 11888