I've taken long-overdue damped and undamped, Phase 3b (with BSC6 at vacuum), transfer functions H1 SUS ITMY's main (M0) chain (formerly H2 SUS ETMY). Attached are the results: 2012-11-19 data is damped, and 2012-11-20 undamped. No surprises -- all mechanics look great / as expected. In processing these measurements, I've made improvements to the QUAD analysis scripts (see details below), so please svn up the QUAD corner of your local copies of the SusSVN. These were taken in-between Vincent's commissioning of BSC6-ISI, so I didn't press my luck to try and get reaction R0 chain measurements. We'll get 'em eventually.
Notes:
- The damped transfer functions use the "final" set of filters and gains that were tuned / used during the H2 OAT, which look to be a little bit too aggressive, but it's a totally "by feel," qualitative assessment. With the newly fixed damped QUAD model, I intend to slap these filters and gains in (instead of the old "legacy" filters and arbitrary from LASTI which are in there now), and predict the test mass displacement -- specifically how much arises from sensor noise re-injected into the SUS vs. residual seismic noise. Stay tuned!
- The data was taken with freshly minted H1 SUS ETMY DTT templates, which can be found here:
/ligo/svncommon/SusSVN/sus/trunk/QUAD/H1/ETMY/SAGM0/Data/
2012-11-19_1840_H1SUSETMY_M0_Mono_L_WhiteNoise.xml
2012-11-19_1840_H1SUSETMY_M0_Mono_P_WhiteNoise.xml
2012-11-19_1840_H1SUSETMY_M0_Mono_R_WhiteNoise.xml
2012-11-19_1840_H1SUSETMY_M0_Mono_T_WhiteNoise.xml
2012-11-19_1840_H1SUSETMY_M0_Mono_V_WhiteNoise.xml
2012-11-19_1840_H1SUSETMY_M0_Mono_Y_WhiteNoise.xml
(The same template is used for both damped and undamped transfer functions, so the date is the only thing one should need to change.)
- I've made several improvements to
${SusSVN}/sus/trunk/QUAD/Common/MatlabTools/
plotquad_dtttfs.m
plotquad_matlabtfs.m
plotallquad_dtttfs.m
(1) I've added a few lines at the end of all three scripts which removes the individual plot .pdfs after they've been merged into the ALL.pdfs. They're just clogging up the svn, and were never use them anyways.
For the "raw measurement" processing scripts, I've
(2) In the interest of getting all the gains right for predicting the damping loop performance, and because we now know the calibrations of the sensor and actuator chains well from independent measurements, I've changed the way the scripts calibrate the data. Namely, I explicitly calculate the [(sensor ct/drive ct) / (m/N)] (or [(sensor ct/drive ct) / (m/N.m)], [(sensor ct/drive ct) / (rad/N)], [(sensor ct/drive ct) / (rad/N.m)] as need be), instead of using the empirically measured value of 60. The number turns out to be 55.0708 [(sensor ct/drive ct) / (rad/N.m)], only an 8% difference, but it also aids in the understanding of improvement (3).
(3) I've added a switch inside the calibration step which -- based on a new, user-input, boolean, variable meas.sensCalib -- determines whether the OSEMINF "to_um" filter has been left ON during the measurement or not. Here's the new lines:
if meas.sensCalib
% <-Sensor-> <---------- Actuator Chain ---------->;
% OSEM Coil Driver Coil/Magnet ;
% Sensitivity DAC TransCond. Force Coeff.;
% [m/um] [drive ct/V] [V/A] [A/N] = [(m/um) . (drive ct/N)];
calibration = (( (1/1e6) ) * ( (2^18/20)*(1/0.009943)*(1/1.694) ))^-1;
else
% <----------------- Sensor Chain ----------------> <--------- Actuator Chain --------->;
% OSEM SatAmp Coil Driver Coil/Magnet ;
% Sensitivity TransImp. ADC DAC TransCond. Force Coeff.;
% [mm/uA] [m/mm] [uA/A] [A/V] [V/sens ct] [drive ct/V] [V/A] [A/N] = [(m/sens ct) . (drive ct/N)];
calibration = (( (0.7/76.29)*(1/1e3)*(1e6/1)*(1/240e3)*(40/2^16) ) * ( (2^18/20)*(1/0.009943)*(1/1.694) ))^-1;
end
Where, for the sensor chain, I've used the calibration as (best) described in LLO aLOG 4291, and for the drive chain, I've used the calibration as (best) described in LHO aLOG 4563 (though the force coefficient is different because HSTSs use 10Dx5T [mm] magnets, and QUADs, BSFMs, and HLTSs use 10Dx10T [mm] magnets on their top stage; the coil driver trans conductance is different because QUADs use QUAD TOP drivers, where HSTSs use Triple TOP drivers). Or, if you like pictures / diagrams, see T1100378.
In case you're worried, we don't have to go back and re-run all of the old data. It's only an 8% change in the calibration, which we know can be less than the mechanical/electronics gain variation between suspensions. I will say though, I re-ran a few older measurements just to test it out, and it does put the measurements right smack on the model now for some of them (nice!).
