J. Kissel, (S. Steplewski)

After putting in the effort of "cleaning up" the infrastructure for H1SUSTMSY (see LHO aLOG 5754), I've taken M1 to M1 (Top2Top) transfer functions, in hopes that Double Model (including a parameter file built by Szymon and myself) we put together would match the measurement as beautifully as the rest of the SUS and their models. 

Attached are the results; no such luck. (Queue sad trombone).

Szymon took a data set before the makeover (shown in orange), with the damping loops closed, so the data definitely won't match up with any model (especially the rotational degrees of freedom), but I plot it anyway to see if we can pull out any useful information comparing it the current data. The current data (in black) was taken last night, after the makeover, with damping loops open.

Since all three show totally different things, it's difficult to know which to trust. However, I'm 90% confident that the current data shows there's rubbing present in the suspension. My reasoning is as follows:
- Driving as hard as I can without saturating, but still see very noisy, poorly coherent data up to 1 Hz, if not higher
- Resonant modes of independent degrees of freedom are seen in each others TF; e.g. ~3.5 Hz Y mode visible in R, T, and L, or 
- Vertical and Yaw modes -- typically very mechanically stable (read: hard to screw up) show noisey/muted resonances peaks

This rubbing might be the source of Keita's complaints that the damping was unstable to increasing the gain. I'd really like to resolve the rubbing issues before I go any further on redesigning the damping loops -- because they may just not need it.

LHO aLOG 1825 is the best thing I can find regarding previous "accepted" transfer functions, and regardless of that the resolution is low, and the measurement frequency band is less, I think it's still pretty clear that those former transfer functions are much cleaner than what I've measured.

I've spoken with Kiwamu, and they'll begin the time-honored SUS tradition of finding sources of rubbing.

In the mean time, we'll continue to refine the model, such that they converge.

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As an aside -- you may recognize the format of the attached plots. This now means that there are functional aLIGO SUS standard analysis scripts that can process and compare data sets. Szymon had started writting them, and I've pushed them through to completion and full functionality. I've also begun building up the svn structure similar to other suspensions. As such, I describe everything:

The data was taken with DTT using the templates:
${SusSVN}/sus/trunk/TMTS/H1/TMSY/SAGM1/Data/
2013-03-11_0800_H1SUS-TMSY_M1_L_WhiteNoise.xml
2013-03-11_0800_H1SUS-TMSY_M1_P_WhiteNoise.xml
2013-03-11_0800_H1SUS-TMSY_M1_R_WhiteNoise.xml
2013-03-11_0800_H1SUS-TMSY_M1_T_WhiteNoise.xml
2013-03-11_0800_H1SUS-TMSY_M1_V_WhiteNoise.xml
2013-03-11_0800_H1SUS-TMSY_M1_Y_WhiteNoise.xml

exported in the format L_EXC to F1, F2, F3, LF, RT, SD, L, T, V, R, P, Y in the files
${SusSVN}/sus/trunk/TMTS/H1/TMSY/SAGM1/Data/
2013-03-11_0800_H1SUSTMSY_M1_L_WhiteNoise_tf.txt
2013-03-11_0800_H1SUSTMSY_M1_P_WhiteNoise_tf.txt
2013-03-11_0800_H1SUSTMSY_M1_R_WhiteNoise_tf.txt
2013-03-11_0800_H1SUSTMSY_M1_T_WhiteNoise_tf.txt
2013-03-11_0800_H1SUSTMSY_M1_V_WhiteNoise_tf.txt
2013-03-11_0800_H1SUSTMSY_M1_Y_WhiteNoise_tf.txt

then individually processed into
${SusSVN}/sus/trunk/TMTS/Common/MatlabTools/plotTMTS_dtttfs.m

which saves a .mat file in a standard format and place,
${SusSVN}sus/trunk/TMTS/H1/TMSY/SAGM1/Results/2013-03-11_0800_H1SUSTMSY_M1.mat
and produces the "individual measurement" plots attached, 2013-03-11_0800_H1SUSTMSY_M1_ALL_TFs.pdf

This file can then be picked up and compared with other measurements by
${SusSVN}/sus/trunk/TMTS/Common/MatlabTools/plotalltmts_tfs.m

which produces the "measurement collection" plots attached, alltmtss_2013-03-11_H1SUSTMSY_ALL_ZOOMED_TFs.pdf 

All of the above are committed to the SusSVN for your future use!