Sorry, numbers here are clearly wrong (proven by the pictures!). Correct ones:
- 5 HAUX towers, complete of almost all accessories
- 10 pairs of blades supports (including blades already paired for each suspension)
- 6 optic holders (excluding the magnets retro-fits) 

Got home, check the locking status ... the arm had dropped lock .... I commanded 'caput H2:ALS-Y_REFL_SERVO_IN1EN 0' followed by 'caput H2:ALS-Y_REFL_SERVO_IN1EN 1'  and the cavity locked ... even more surprising it had a REFL power of 7000 ... and it started to move up automatically to 9200!! It seemed that the WFS are working

I tried to write an auto locker script but I hidiously failed. Although it may have something to do with a remote shell. I disengaged the REFL servo as it dropped lock and would not come back in the time I was trying to write the script.

We centered the WFS and repeated the measurement of the sensing matrix. We did it in two ways: a) measuring the frequency response of the PIT and YAW outputs of both BFS A and B when exciting the POS and ANG mode of the cavity at about 4 Hz; b) introducing offsets in the cavity's POS and ANG degrees of freedom and measuring the displacement of the PIT and YAW output of the WFS.

The first method gave us almost degenerate sensing matrix. The second one seemed a bit better. The measured matrix M was:

M =
    0.0157   -0.7306         0         0
    0.0708   -0.6684         0         0
         0         0    0.0598    0.1663
         0         0   -0.0210    0.3363

The PIT and YAW inverted matrices were:

iP =
  -16.2163   17.7263
   -1.7176    0.3814
iY =
   14.2483   -7.0453
    0.8899    2.5339

These are the matrices used for the overnight arm cavity locking.

Th eigenvectors of these matrices are:

VP =
   -0.9931   -0.7741
   -0.1177   -0.6331

VY =
    0.9968    0.5341
    0.0795    0.8454

(see below)

This doesn't look crazy, though the two WFS heads are not optimally placed and the table astigmatism is not minimal either.

PIT sensing matrix that Bram posted in the above elog entry actually means this:

|WFSA| = |0.0157  -0.7306| x |POS| = |-0.7306  0.0000| x |-0.021  1| x |POS|
|WFSB|    |0.0708  -0.6684|    |ANG|    | 0.0000 -0.6684|   |-0.110  1|   |ANG|

The columns correspond to POS and ANG excitation, and the rows represent the WFS heads. (Sorry for the crappy formatting, I hope you get that I'm trying to write a matrix equation.)

POS refers to the translation of the cavity axis caused by the rotation of ETM and ITM in the opposite direction by the same amount. ANG refers to the rotation of the cavity axis by the rotation of the ETM and ITM in the same direction by the same amount.

For WFSA, ANG PIT generates a factor of 50-ish bigger signal than POS PIT. For WFSB, ANG IT is about a factor of 10 bigger.

Similarly, if you take the YAW matrix it's this:

|WFSA| = | 0.0598 0.1663| x |POS| = |0.1663 0.0000| x | 0.36 1| x |POS|
|WFSB|    |-0.0210 0.3363|    |ANG|    |0.0000 0.3363|   |-0.06 1|   |ANG|

If you look at the YAW numbers (not shown here but see the above entry by Bram), WFSA is a factor of 3-ish more sensitive to POS YAW than ANG YAW, and for WFSB this is a factor of 16.

Because of the cavity geometry (see below) ANG naturally produces a factor of 3 larger signal than POS. That means that, in terms of Gouy shift from the center of the cavity, WFSA for example is located at atan(-0.021*3) = -3.6 degrees away for PIT. Note that there's an uncertainty of n times pi that is common to all DOFs, and also the sign is sort of arbitrary though it should be consistent for both WFSs.

Anyway, below is the table of Gouy shift: from the waist of the arm in degrees (the above caveat about uncertaintly applies).

           PIT         YAW 
WFSA |  -3.6 deg | +47   deg|
WFSB | -18   deg | -10.6 deg|

PIT and YAW difference in WFSA looks kind of suspiciously large, but I would say that the crappy beam quality on the table could be blamed. It's not the TMS telescope (if it is, we'll see the same thing in WFSB too).

All in all the WFS locations could be adjusted better, and certainly the beam on the table is not passing through the center of lenses, but if the servo works (which we'll find eventually) I'll leave it.

----

Why a factor of 3 naturally?

Because we're using ETM substrate for both ETM and ITM, ROC of both is about 2300 m (2312 for EY, 2307 for IY).

Waist (w0=11.5mm for green) is at the center of the cavity, and the divergence angle is theta0=14.6 urad.

If we rotate both of the mirrors by the same amount (theta) as if one is the mirror image of the other, the cavity axis is purely translated by 2000m*theta. In terms of the higher order mode excitation, this is equivalent of

Normalized POS = 2000m * theta / w0 = 1.7e5 * theta.

ANG: If we rotate both of the mirrors by the same amount (theta) in the same direction, the cavity axis is purely rotated around the waist by (2300m * theta * 2)/600m. This is equvalent of

Normalized ANG = (2300m * theta * 2)/600m/theta0 = 5.3E5 * theta.

Therefore a factor of 3.

The transfer functions measured last night had features that are typical to mis-connected sensors/actuators. Deeper analysis allowed narrowing it down the the GS13s. 

Hugh and I added screwdriver tips under the top payload mass of HAM2-ISI last week, before the chamber was closed. They helped prevent this big mass of ~600lbs from causing unwanted resonances. Befoire/After comparison plots are attached.

We compared the latest transfer functions with the ones taken on LLO HAM2-ISI during the same phase of testing (Intitial In-Chamber Testing). Plots are attached. Accordance is good. We are confident that the unwanted resonance seen at 96Hz comes from the top mass. We plan on ajusting its boundary conditions with the optical table once the doors of HAM2 chamber are open again. 

h1isiham2.mdl was modified to apply a constant at the error input of the HAM2_PAYLOAD block (see attached picture). The constant value is 0. It corresponds to the Dolphin communication error value for the state of SUS model running

Modifications were commited to the SVN. The model was re-compiled, installed, and re-started.

It allowed untripping the ISI. Actuation is now possible. Actuators respond on all corners, and they appear to be correctly wired.

This modification of h1isiham2.mdl will have to be reversed when rcg is updated on site (planned for 08/28/2012). 

The modifications applied to SUS's models will need to be reversed when suspensions are installed on the ISI.

The logout issue is a known limitation with the LIGO.ORG authentication on shared workstations.  You need to completely close/kill the browser, or open a different browser (not just a different browser window).

The authentication is not handled by the application, it is handled by the LSC auth project login server (login.ligo.org).  Clicking aLOG log-out button does in fact clear all state in the application associated with your session.  The issue is that the aLOG does not have a way to affect the state of login.ligo.org.

So this is a known issue, it will be fixed at some point.  The benefit in account and password management of using the LIGO.ORG credentials appears (by far) to outweigh the inconvenience of having to kill the browser when you work at a shared workstation.

The first of your requests has been a request since last summer, see LHO aLOG 1000. I know Jonathan Hanks is working on this.

I restored ISCEY, ETMY and TMSY to 3am, 22 August 2012.

Laser was restarted yesteday, with the FSS and PMC servos running. The ISS is off because it keeps glitching with work on the table. Watchdogs are on.