Filiburto replaced the DC power supply in h1susauxh56's IO Chassis. We restarted the front end and all looks good with this system.
11:02 and 11:06 DAQ restarts due to following changes
The second restart was due to duplicate channels in the DMT broadcast. The number of channels this system handles went from 271 to 854.
EDCU is PURPLE due to Guardian changes, Jamie will produce a new H1EDCU_GRD.ini file when his changes are complete.
h1ecatc1 seemed to be running, but nothing was getting to epics. When I tried to login to PLC2 the PLC control crashed. I restarted the machine, and reran the install scripts, but the PLC control keeps crashing.
We also got the message callBackRequest: cbLow ring buffer fulll
Daniel fixed the problem by reseting each PLC, deleting the target directories, and re running the install scripts. When he did that, the PLC Control were still crashing, at which point he used the restart button in the lower right hand corner to restart the system.
Now things seem to be back.
I burted all three PLCs to 11:00on feb 14th (Friday)
Power down H1LSC to fulfill Work Permit #4446 (remove a DAC card from IO Chassis) and also restart ISC EX model
Working on SR3
Looking at the ELIGO TCS viewport
Passing on a note sent to LHO Operators with regards to the FOMs. If you have suggestions/desires for what we want/removed on these FOMs please let Dave B. or myself know.
Note on FOMs for Operators:
The Wall TV Screens (aka FOMs) have been approaching a state where what we want on them is becoming useful and consistent. As part of a shift task, let's make sure these Screens look good. Once we have a Checksheet, we'll be sure to add checking the FOMs on it.
At 8:30 AM PT, it's been noticed that the PSL ref cav is attempting to lock but keeps dropping out. Sheila D. has been informed.
[Yuta, Rana, Evan]
When Stefan left Friday evening, PRMI wouldn't lock. We poked around at MEDM screens for a while before deciding that a more systematic diagnosis was in order. We decided to attack just the Michelson first.
We parked PRM and misaligned ETMX. We then adjusted the LSC MICH filter bank to duplicate was was done for Kiwamu's and Yuta's previous Michelson lock characterization (elog 9698, 31 Jan 2014). Even with a 1:0 integrator engaged, we found that the Michelson would not lock for more than 30 s, and the error signal drifted by about a third of its peak-to-peak.
We were able to measure the OLTF, and found that it had a UGF of 3 Hz with no phase margin. Rana suggested we notch out the bounce mode of the BS suspension with filters from LLO. We got the filter, adjusted the frequency to the LHO BS (17.8 Hz, as measured from the REFLAIR_A_RF45_Q_ERR spectrum), and then added it to FM6 on LSC_MICH. After doing this, we found that the Michelson lock is much more stable --- it appears to lock indefinitely.
In order to calibrate REFLAIR_A_RF45_Q_ERR in terms of mirror motion, we let the Michelson swing freely and recorded the fringing. We know that the fringing amplitude (in counts) as a function of asymmetry l is A sin(4 pi l / lambda), so the linear portion has a slope of A * 4 pi / lambda, in counts per m. I took the swinging data, trended the minimum, median, and maximum, and then took the median of the trended minimum and maximum values. A histogram of these values is attached. From this I find A = 643 counts; this gives the conversion factor as 7.6 counts per nanometer.
We used this value to get a calibrated spectrum of the dark noise of REFLAIR_A_RF45_Q_ERR, which we measured with the modecleaner unlocked. A trended 10-minute time series is attached; we see that the drift is on the order of a few nanometers over this time period. Also attached is a spectrum of the dark noise, along with Yuta's estimate of the control signal (LSC_MICH_OUT) the Michelson, given in terms of length. The estimated length noise was 1.1 um RMS.
An OLTF of the improved Michelson loop is attached. The UGF is now 7.5 Hz, with a phase margin of 20 degrees. Also attached is Yuta's model of the expected OLTF; the agreeement is excellent around the UGF, except for the flat gain. This model uses already existing an already of the triple suspension of the BS (/ligo/svncommon/SusSVN/sus/trunk/Common/MatlabTools/TripleModel_Production).
We assumed that the suspension model gives BS actuation efficiency from H1:SUS-BS_M2_LOCK_L_OUTPUT to the actual M3 motion in m/counts. However, there is a missing factor of 1.7e-3 in this actuation efficiency to fit to the measured OLTF.
Written by Yuta
I found that I forgot to put 0.05 in my OLTF model (I forgot that the output matrix H1:LSC-OUTPUT_MTRX for MICH to BS was set to 0.05). I also forgot to put sqrt(2) to convert BS motion to MICH length change. I updated the OLTF figure, and now, the missing factor is 0.024.
Written by Yuta
The missing factor 0.024 was from the conversion factor in uN/counts.
I assumed that the suspension model I use gives me the transfer function in m/counts, but it was actually in m/uN.
The conversion factor can be calculated using the parameters in G1100968 (for BS specific, see T1100479);
0.963 N/A * 0.32 mA/V * 20.0/2**18 V/counts = 2.35e-8 N/counts = 0.024 uN/counts
The OLTF now agrees well with the expected. Thanks to Jeff K. and Arnaud!
(But still, there is a missing factor in the PD signal chain. The measured value 7.6 counts/nm is used in this expected curve. See alog #9630 and #9857)
Note that this factor(uN/counts) is also missing in the current noise budget model which lives in /ligo/svncommon/NbSVN/aligonoisebudget/trunk/PRMI.
Alexa, Sheila
The x end ethercat was not running when we got here. It had the choose runtime system error. I created botprojects for each plc, as I was doing that the computer crashed. I restarted again using the restart script, the plcs were running when it came back up. I burted all three to friday at 11:00
A bunch of guardian upgrades were done over the weekend:
guardian core was upgraded. it's currently at r720, but it's still moving as bugs are identified and features added
cdsutils (ezca) was upgraded . currently r164, but again still working out some kinks.
The guardian supervision infrastructure was upgraded and moved to a new location on local disk on h1guardian0. I'll report on the new infrastructure in a followup post. This required killing the main process supervisor ("initctl stop guardian-runsvdir"), which shut down all the current guardian nodes.
The SUS base guardian code was upgraded. The base SUS.py was copied over from LLO. Some improvements have been made as well, which I'll report on later. Once this was in place I brought up the SUS_SRM node for testing. Was it seemed to be behaving well the SUS_MC{1,2,3} nodes were restarted. The rest of the SUS nodes were left off for the moment, but will be restarted tomorrow.
The IMC autolocker code was upgraded. The new code is based on the code that was developed at LLO. Again, to be expounded later. The IMC autolocker upgrad exposed some issues with the current guardian behavior that will need to be fixed tomorrow.
Last week with Andres's help I measured resonance frequencies on SR2 in the double and single hang cases (top locked on stops and middle locked on stops respectively). This log reports the results of fitting the hsts model to that data. The adjusted parameters are listed below with the estimated error bars. Typically I allow d1 (top mass spring tip height) to move. Interestingly, the model had better results when the height of the bottom mass prism was allowed to move instead. Floating d1 did allow the resonances to line up with similar precision, however d1 and I1y would drift very far from their nominal positions to do this, about 5 mm on d1 and 50% on I1y. The attachment H1SR2_ModelFit_17Feb2014.pdf shows the measured transfer functions against the nominal model and the model fit. The measured L-P/P-L and T-R/R-T TFs do not show good symmetry, so those comparisons should be taken with a grain of salt. Likely the OSEM balancing is poor as poor balancing will cause errors in the measured zero locations. Similarly, the 1.5 Hzish zero on the measured Roll to Roll TF is probably slightly off from reality. It does not correspond exactly to the measured double hang Roll resonance as it should, and it is also somewhat off from other HSTS suspensions. The attachment H1L1SR2comparison_17Feb2014.pdf shows the same results but against L1SR2. The new model also fits L1SR2 better, though there are some minor differences. The new parameter file is on the svn at ...sus/trunk/Common/MatlabTools/TripleModel_Production/hstsopt_H1SR2fit.m The model fitting code for H1SR2 is on the svn at ...sus/trunk/Common/MatlabTools/TripleModel_Fit/TripPend_GaussNewton_fit_v5_H1SR2.m Change in parameters from original model with the estimated minimum errors --------------------------------------- d4: -1.6798 +- 0.094782 mm I1x: -6.3844 +- 1.2588 % I2x: -5.2885 +- 11.4653 % I3x: -3.706 +- 12.1017 % I1y: 8.8773 +- 0.61371 % I2y: -5.583 +- 0.5374 % I3y: -4.6949 +- 0.36401 % I1z: -5.7573 +- 0.9752 % I2z: 1.2902 +- 1.0012 % I3z: -3.2293 +- 0.30808 % l1: 5.5655 +- 3.3226 mm l2: 4.2327 +- 0.52961 mm l3: 1.4169 +- 0.40356 mm kc1: -1.2835 +- 1.2589 % kc2: 2.4943 +- 0.4258 % ---------------------------------------
tmtsopt_firstarticle tmtsopt_firstarticle tmtsopt_production r4580 r6273 r6273 -------------------------------------------------------------------- modeY1 0.355864 modeY1 0.357487 modeY1 0.356438 modeT1 0.447407 modeT1 0.44897 modeT1 0.44903 modeL1 0.473763 modeL1 0.474697 modeL1 0.474545 modeR1 0.678918 modeR1 0.679192 modeR1 0.650001 modeP1 0.713869 modeV1 0.73404 modeP1 0.729786 modeV1 0.729389 modeP1 0.754609 modeV1 0.750216 modeT2 1.38385 modeT2 1.36581 modeT2 1.37346 modeL2 1.72689 modeL2 1.72179 modeL2 1.73388 modeV2 2.40587 modeV2 2.40182 modeV2 2.40454 modeP2 2.44574 modeP2 2.44429 modeP2 2.56147 modeY2 2.59116 modeY2 2.58853 modeY2 2.71571 modeR2 4.27789 modeR2 4.14866 modeR2 4.31193
The ALS-X BBPD appears to have gone dark around 2:30 PST on Friday. The EX laser IR PD and fiber monitor PDs appear to have been disturbed around the same time, but they have recovered.
Possibly this is related to Friday's work on installing WFS on the ISCTEX table, or the related editing of the X-end simulink models.
The +-18V PD power supply cable for the table was unplugged at the power strip on the field rack. All DC diodes connected to the DC diode interface were down.
Should work now.
Don't know why it was unplugged, it's hard to accidentally plug it off.
(Blue Team)
Short progress report:
More details to follow.
Results of my visit to LHO this week for system identification of the ETMY.
MOTIVATION:
Make better models for each particular suspension to aid control design and noise predictions.
The measured frequencies of the resonances are the most reliable data we have because they are not subject to errors in the sensors or actuators. There are also numerous resonances available for measurement, which can be used to adjust the model.
SETUP:
Resonance measurements were collected on ETMY main chain while on the test stand in the follow configuration with the following methods:
* full quad - top mass to top mass transfer functions using the OSEMs. This data was measured prior to my visit this week.
* triple hang - with the main chain top mass, reaction chain UIM and PUM masses locked on stops, spectra of the lower three main chain stages were measured with the UIM and PUM OSEMs and an optical lever on the test mass. No excitation is needed since the wind from the fans is more than enough. The process of locking the masses also misaligns the UIM and PUM OSEMs sufficiently that they are sensitive to vertical, roll, and transverse displacements of the stages. This allows us to measure more resonances with these OSEMs then we otherwise would. The optical lever isn't sensitive to any resonances the OSEMs miss, but it does add redundancy to help identify a forest of high Q pendulum resonances from spectra that include a lot of similarly shaped artifacts.
* double hang - with the main chain UIM and reaction chain PUM locked on stops, spectra of the main chain lower two stages were measured with the PUM OSEMs. In this case the optical lever would not stay in range, so the data is just the 4 PUM OSEMs.
* single hang - with the PUM on the teflon line stops, the test mass modes were measured with optically. This data was measured prior to my visit.
SUMMARY:
The data encompasses 56 resonance frequencies: 22 free quad, 16 triple hang, 12 double hang, and 6 single hang. See the attached plots and the summary of parameter changes below. In the attachment the black curves are the measured data, the blue the original model, and the red the new model. Pages 1-6 of the attachement show the diagonal top mass to top mass transfer functions. Pages 7-8 show L-P coupling and 9-10 T-R coupling. 11-13 are the frequencies of the triple, double, and single hangs respectively. 14 plots the mode frequency percent errors before the fit and 15 shows the same after the fit. The final page shows the convergence of the total error, where the error is calculated as
sum( [(measure mode - modeled mode)/(measured mode)]^2 )
The algorithm for fitting the data is Gauss-Newton, an approximation of Newton's method. The fitting code is on the svn at .../sus/trunk/QUAD/Common/MatlabTools/QuadModel_Fit/QuadPend_QuassNewton_fit_v2_H1ETMY.m.
Change in parameters from original model with the estimated convergence errors:
---------------------------------------
Inx (top mass roll inertia) : -1.0926 +- 2.6994 %
Iny (top mass pitch inertia) : 3.1636 +- 3.4396 %
Inz (top mass yaw inertia) : -0.86123 +- 0.65824 %
I1x (UIM roll inertia) : 3.9571 +- 0.77982 %
I1y (UIM pitch inertia) : 12.2729 +- 2.5078 %
I1z (UIM yaw inertia) : -0.10972 +- 0.55984 %
I2x (PUM roll inertia) : -2.9587 +- 0.85205 %
I2y (PUM pitch inertia) : 8.4597 +- 0.6904 %
I2z (PUM yaw inertia) : 0.011768 +- 0.3983 %
I3x (test mass roll inertia) : 2.2009 +- 0.77109 %
I3y (test mass pitch inertia) : -8.8738 +- 0.79819 %
I3z (test mass yaw inertia) : 0.44122 +- 0.5629 %
l2 (PUM wire loop length) : 8.6866 +- 1.1464 mm
l3 (fiber length) : 22.1269 +- 2.6176 mm
kcn (top stage spring stiffness) : 1.0719 +- 2.166 %
kc1 (top mass spring stiffness) : 1.0935 +- 0.68178 %
kc2 (UIM spring stiffness) : 2.2795 +- 0.39067 %
kw3 (fiber bounce stiffness) : 9.4286 +- 0.4488 %
dn (top mass blade tip height) : -0.20928 +- 0.303 mm
d1 (UIM blade tip height) : 1.8131 +- 0.56431 mm
d4 (effective fiber flexure at test mass): -4.8356 +- 0.23685 mm
---------------------------------------
DISCUSSION:
The fit of the original model was fairly descent already, except for pitch. The fit of the new model to this data is even better, especially for pitch. The worst mode frequency error decreases from 8.2% to 1.3%. Interestingly, even though only resonance frequencies were included in the fit, the shapes of the transfer functions (including zeros) all match well also. This goes for the cross coupling measurements as well. Note, the length to pitch measurement does not match the pitch to length. These should in theory be identical. Mismatches indicate measurement problems. Length to pitch has some low frequency notches that don't exist in pitch to length. Judging by the models (both before and after), I think it is likely that pitch to length is the more accurate measurement up to 4 Hz. I don't think we can believe either beyond 4 Hz. After the fit, the worst error in mode frequency corresponds to the first roll mode for both the free quad case and the triple hang case.
The inclusion of the extra resonance frequencies made a huge difference in the ability of the model to converge. In this case, a total of 21 parameters were floated. Normally, only a few at a time can be floated using just top mass data.
Many of the parameter changes produced by the fitting code seem quite reasonable. Some that are beyond what you would expect are the lengths of the fibers and the PUM wire loop. These changed by 22 mm and almost 9 mm respectively. Since the mass values are known, the only way to fit all 10 measured longitudinal modes is to adjust the wire lengths. This was achievable by floating both these wire/fiber lengths. I noticed that the default value in the original model for the PUM wire loop has the following comment: "% wire hang value - Mark Barton, 11/22/2011". I wonder if the entered value is no longer correct since the quad is not in the 'wire hang' configuration anymore. Regarding the fibers, the effective flexure length is rather complicated due to the geometry of the fibers. Perhaps some other error, like in fiber radius can mimic this. Note, the bounce mode stiffness moved by 9%.
The d4 change is also large. It is very likely this value is not physical because this parameter has significant degeneracy with both d3 and d2. Thus, the decrease of 5 mm could be spread out between all 3. d2 also has twice the sensitivity, so a small shift there can take up a fair bit of this 5 mm on its own. These degeneracies prevent the fitting code from floating these parameters simultaneously, so you simple have to pick one. d2 is sort of awkward because it is degenerate enough that it is difficult to float with either d3 or d4, but different enough that floating it instead of d3 or d4 yields different results.
DISCLAIMER:
As usual, the choice of parameters to float was made by experience and intuition. These parameter changes are not necessarily representative of reality. Though, with a fit that matches all 56 measurements to the 1% level, you might start to think that this thing is converging within some distance of reality.
COMPARISON WITH FUTURE MEASUREMENTS:
We should see how this new model holds up against L-P measurements at other stages and between stages.
NOTES:
The high frequency vertical and bounce modes were visible on the single hang and double hang measurements, but not the triple and free quad. If they were visible in all there would be 60 measured resonances. However, these modes are virtually the same from double hang to triple hang to free quad because they involve primarily displacement between the bottom two masses. Thus, the loss of information is negligible. In fact, we might be better off not including these extra bounce modes in case they emphasize bottom mass parameters over the upper masses since the same information would essentially be repeated 3 times.
I found a typo in the model fitting code that explains the change in the fiber length. In the code the nominal d3 and d4 values, each 10 mm, were subtracted from the fiber length. The fitting code, doing what it is supposed to do, detected that the fiber length was incorrect and added 22 mm to compensate. The 2 mm difference is in the noise since the fiber length has a weak influence on the dynamics at the mm level. Note that the code did output a +-2.6 mm error bar for this fiber length change. I'll take this as good news that the fitting code works. The model fitting code has been updated on the svn with the bug fix. The new parameter file is on the svn at: /ligo/svncommon/SusSVN/sus/trunk/QUAD/Common/MatlabTools/QuadModel_Production/quadopt_fiber_H1ETMY.m
The following attachment shows that the new model is also a good match for L1ETMY.
A new alog entry at https://alog.ligo-wa.caltech.edu/aLOG/index.php?callRep=10476 discusses the calculation of the UIM-PUM wire length required from the model based on the wire jig document and PUM drawings. These documents bring the wire length much closer to what the model fitting code found.
I temporarily installed a modal damping filter on the longitudinal degree of freedom of ETMX. The filter has 32 poles, so it is split between two modules, 'md_part1' and 'md_part2'. I plan to measure ringdown times of the test mass tomorrow using the green cavity signal. This is part of an effort to see what are the fastest possible ringdown times of the test mass with top mass damping. After the test I will remove the filters. Normally a modal damping filter wouldn't need this many poles, but I decided to include the pitch dynamics in the estimator to get a more faithful reproduction of the 1st longitudinal mode frequency for this test.
Measured results taken last wednesday. See the attachment. The damping on each mode was set so that each would ring down to 1/e in about 9 seconds. The first page shows the measured and modeled closed loop top mass to top mass transfer function with the longitudinal DOF damped modally. The next 3 pages shows the measured and modeled impulse responses of the UIM, PUM, and testmass respectively. The impulse is injected into the top mass with the test excitations, the measurement is taken with the OSEMs at the UIM and PUM and the green cavity at the test mass. The impulse was set so that it was faster the the highest frequency longitudinal mode. The measurements and model agree quite well. In the ringdowns there is a noticeable phase shift by the end of the 20 seconds because the model has not been fit to the ETMX yet. The cavity measurement also has some extra error becuase the cavity had large drifts and it was difficult to get enough signal without unlocking the cavity.
Same plots but against the new fit of the ETMY model (and this is actually on ETMX). Also included are the number of seconds it takes to get to 1/e of the maximum. I also tweaked the modeled pitch damping filter to make the first pitch mode have similar damping to the measurement. I didn't write down what the actual pitch damping filter is, so this is just a guess. This helps the cavity ringdown match the measurement more precisely. The pitch damping has a non-negligble influence on the cavity ringdown, since the first pitch mode is so close to the first longitudinal mode.