Thomas Vo and Bob Anderson reported yesterday to me that the ACB is down off the ISI.

Yesterday, SEI disconnected the ISI cables from the Feedthrus and secured them up above the ISI Stage0.  We also removed nearly 700lbs pulling the Keel Ballast Mass off along with the Stage1 Trim Mass.  The Mounting Pads are installed and torqued.  Also the Stage0/Support Tube bolts are all but a few removed and those are confirmed free and ready to easily extract.
We are ready to crane the Tri-Lift Spreader into position and connect up to the Cartridge.  We still need to fuss a bit with the sequencing of balancing the lift, lowering the cleanroom and positioning/opening covers.

Thanks to Jim and Mitchell and especially Jodi for helping securing, offloading, and wrapping up our goods.

As requested by Jeff K, I have updated the compensation filters for H1 HXTS suspensions. A similar update previously been carried out at LLO by Joe B (see LLO aLOG entry 4417). 

The process was first tested with the SR2 (HSTS) suspension, using the prepare script, located in "/ligo/svncommon/SusSVN/sus/trunk/Common/MatlabTools/", with the following Matlab command:-

prepare('H1','SUS','SR2','HSTS')

Updated foton filter files were then visible from the GDS_TP screen for h1sussr2. The "Coeff Load" button was selected to import the new filters. A cursory check over the medm screens indicated that new filters were in place (see note below).

This was then repeated for PR3 (HLTS), PR2, PRM, MC3, MC2, and MC1.

The process initially failed (hung-up) for MC2, as this was found to already have in existence h1susmc2.txt.bak and h1susmc2.bak.txt, which prevented the process from completing. Once these were deleted, prepare scripts could complete.  

N.B. it was observed that the following models did not contain any DAMP filters: SR2, PR3, PRM. I shall confirm if this is intended with Joe B or Jeff K.

Tim N, Gerardo M, Bob A, Thomas V

We have removed the ACB in BSC8 completely off of stage-0.  The parts are currently residing in the beam tube along with the lift table that will be sent to the machine shop for re-work per Tim N.  All parts will be extracted from the chamber once the cartridge is removed.

One note is that 5 AG-plated SHCS were still stage-0, I believe these were the hand tapped holes that were used for the pushers during installation and left in as plugs for any particulate from the tapping process, I wasn't sure if I should remove them so I left them in. 

Cheryl and I spent some time working on the iLIGO Core Optics today. This morning, we verified the identity and location of the optics going to KAGRA. After lunch and re-reading the packing procedure, I verified that two of the KAGRA optics are ready for shipment. I also removed all old labels from the cake tins to avoid confusion on the part of those receiving optics from us. In addition, the Apollo crew wiped down the grey optics shipping cases and moved them into the LVEA. I moved the cases around to the cleaning space just outside the H1 electronics room. We will inspect, document and attempt to pack two KAGRA optics tomorrow morning.

- many of the usual deliveries, bottled water, rugs...
- LN2 truck filled EX CP8, so it's sitting at 99%
- Arm cavity baffle activity in chamber-side cleanrooms along HAM2/3, so sporadic alarms at levels of 150-250 counts, that cleared shortly after alarming
- reboots of H2 by Dave and Jim, so lots of red on H2 alarm handler
- some dust monitors are invalid, I changed levels for dust monitor at EY - see my earlier alog

[Stuart A, Betsy B and Travis S]

M1-M1 Matlab TFs were run in parallel yesterday evening, with damping loops OFF, for MC2 and PR2. This morning it was reported that the MC2 measurement had failed due to inability to extract frame data (and not a tripped watchdog as first thought).

However, the PR2 measurement was unaffected, with results available below (see 2012-10-01_H1SUSPR2_M1_ALL_TFs.pdf).

The MC2 TF was repeated again this morning, with no changes to the Matlab script, and it had completed by 2pm, generating the results available below (see 2012-10-02_H1SUSMC2_M1_ALL_TFs.pdf). 

(n.b. I suspect that trying to run two parallel Matlab TFs is pushing it a little far and so will line them up sequentially next time).  

Both sets of TFs are in good agreement with model predictions (blue traces).

For your viewing pleasure, I have also compared the Phase 3a H1 TFs with the equivalent L1 Phase 3a TFs in the final plot below (see allhstss_2012_10_02_Phase3a_MC2PR2_ALL_ZOOMED_TFs.pdf).

Each suspension looks to be freely suspended, and so we can now proceed to the B&K measurements.

While working on AOSEM alignment yesterday, I noticed that a set screw was missing from the UL AOSEM at the M3 stage of PR2.  In attempting to reinstall it, as it is installed from the bottom up, I dropped the set screw.  After failing to locate it, I had to assume that it had fallen into the HAM-ISI through one of the 1/4-20 thru-holes in the optical table within the footprint of the suspension.  After consulting with Hugh and Jim, we decided it is likely not a problem, but we will conduct a more thorough hunt for it the next time the chamber is available for entry.  For reference, the rogue screw is a #4-40 x 0.112, so about the same size as the average piece of rock salt. 

We resumed analysis of MC3 Phase 2a data taken Sept 27 and found that now the sus ails from pretty severe yaw to vertical and transverse coupling.  Travis eye-balled the suspesnion and sees that it is not well aligned in Yaw.  Note, the alignment procedure during the build phase of HXTSes is all done "by eye".  I think we possibly have been aligning suspensions to the crocked side flag mount (a recent discovery).

Note to self, our recent issues with processing the plothsts_dtttfs.m script was due to file naming convention.  Watch for dash and underscore locations in the name!

A couple of incorrect sign conventions were identified in the EUL2OSEM and OSEM2EUL matrices. This affects the Transverse -> SD OSEM coupling elements and Vertical -> T1T2T3 OSEM coupling elements. These elements incorrectly possessed a positive (+) rather than negative (-) sign.

This was previously corrected for at LLO (see LLO aLOG entry 4023), and has now been corrected at LHO, using a similar method.

The following H1 suspensions had their matrix elements rectified: MC1, MC2, MC3, and PR2.

Safe BURT snapshots were taken of each of the above suspensions.

The above safe snapshots were then committed to the svn.

N.B. This change should be checked for future H1 suspensions too, i.e. PRM and SR2, since HLTS's are unaffected.

I consulted with Patrick, and the dust monitor at EY that was alarming this morning had alarm levels that are used for sampling inside a clean room.  The dust monitor may still be in the clean room, but the clean room is off, so I set the alarm levels to the nominal "outside" a cleanroom numbers.  This change is to EY dust monitor 1.

In cleanroom: for both 0.5u and 0.3u 
Minor = 100.0
Major = 200.0

Outside cleanroom:

for 0.5u:
Minor = 20000.0
Major = 100000.0

for 0.3u:
Minor = 10000.0
Major = 50000.0

The 9/27 ISI move and BS suspension takedown (partial) photo collections now sit in ResourceSpace. 

I installed the HAM-ISI control loops level-2 on HAM2-ISI. To do so, I had to implement the notches I already added to the level-1 loops. I also added a couple other notches to respect the gain margin requirements.
Simulation Plots

Switching from level-1 to level-2 with the MEMD command window worked well, without tripping the ISI watchdogs.

I took sprectra on HAM2-ISI with those loops on. I compared those spectra with the ones measured yesterday, in the following configuration:
  - no active control
  - Damping only
  - Cotrol level-1 with boost and notches

Data is under the SVN. Spectra are attached.

[Stuart A, Jeff B and Andres R]

The following OSEMs have been installed into the SR2 (HSTS) suspension, as well as entering gains and offsets into the OSEM INPUT filters:-

BOSEMs
M1-T1, s/n = 076, open-light = 26125.3, offset = -13063, gain = 1.148
M1-T2, s/n = 423, open-light = 27116.1, offset = -13558, gain = 1.106
M1-T3, s/n = 646, open-light = 25764.8, offset = -12882, gain = 1.164 (c)
M1-LF, s/n = 150, open-light = 31458.2, offset = -15729, gain = 0.954
M1-RT, s/n = 098, open-light = 25390.6, offset = -12695, gain = 1.182
M1-SD, s/n = 668, open-light = 25655.6, offset = -12828, gain = 1.169 (c)

AOSEMs
M2-UL, s/n = 232, open-light = 26261.4, offset = -13131, gain = 1.142
M2-LL, s/n = 213, open-light = 27884.6, offset = -13942, gain = 1.076
M2-UR, s/n = 279, open-light = 25761.6, offset = -12881, gain = 1.165
M2-LR, s/n = 366, open-light = 26451.8, offset = -13226, gain = 1.134

AOSEMs
M3-UL, s/n = 312, open-light = 26656.6, offset = -13328, gain = 1.125
M3-LL, s/n = 424, open-light = 25976.2, offset = -12988, gain = 1.155
M3-UR, s/n = 285, open-light = 25678.3, offset = -12839, gain = 1.168
M3-LR, s/n = 304, open-light = 25379.6, offset = -12690, gain = 1.182

Stemming from an incorrect ICS entry regarding BOSEM #646's characterisation status, SR2 currently has two characterised BOSEMs installed on M1. The M1-T3 BOSEM will be swapped out at the earliest convenience.    

It should also be noted that the M1-SD BOSEM has been re-located to the opposition side of the structure, as requested by systems, and already implemented at LLO. The change of sign then had to be accounted for in the COIL OUTPUT filters (by flipping gain sign from -1 to +1).

Firstly, a set of M1-M1 TFs were taken, with damping loops OFF, for all DOFs (see 2012-10-01_0900_X1SUSSR2_M1_ALL_TFs.pdf), which show good agreement with the model. These TFs were then repeated, but with damping loops ON.  

Secondly, both damped and undamped TFs obtained have been compared to all other LHO HSTSs tested at Phase 1b (see allhstss_2012_10_01_Phase1b_SR2_ALL_ZOOMED_TFs.pdf). 

Thirdly, power spectra have been taken with damping loops both ON and OFF for each stage (see 2012-10-01_1700_X1SUSSR2_M*_ALL_Spectra.pdf).

Power spectra data, with both damping ON and OFF can then be compared to a similar HSTS, PRM, during Phase 1b testing (see allhstss_2012-10-01_X1_SR2_Phase1b_ALL_Spectra_Don.pdf and allhstss_2012-10-01_X1_SR2_Phase1b_ALL_Spectra_Doff.pdf).

In addition, power spectra for specific degrees of freedom (L, P and Y) can be more conveniently compared across multiple stages (M1, M2 and M3) of the same suspension in the final plot found below (see allhstss_2012-10-01_X1_SR2_Phase1b_X1SUSSR2_M1M2M3_Spectra_ALL_Don.pdf).

Finally, all data, plots and scripts have been committed to the SUS svn as of this entry.

This should now be sufficient to complete Phase 1b testing of the SR2 suspension.

Tim N., Gerardo M., Bob A., Thomas V.

Today we assembled the support table (D1101953) with lab jacks and brought down the box portion of the Arm Cavity Baffle.  Since we were waiting for a few tooling parts to be baked (they did not fit in the bake oven on Friday), we will assemble the installation lift stand (D1101957) tomorrow in order to bring down the suspension portion of the ACB.  

Both the suspension and the box portion will be laid down in the tube while the cartridge is being removed, then the suspension and box will be extracted afterwards.   

HAM2-ISI features an unusual high Q resonance at 96.1Hz. This resonance is due to the top payload mass that still needs better boundary conditions with the ISI (see aLog comment #4025).

The seismic team uses generic controllers for the first level of the HAM-ISI controls.  The watchdogs of HAM2-ISI would trip on the actuators' signal when turning on those controllers. Indeed, the generic controllers did not account for such feature and the unusual resonance would consume most of the gain margin (Simulation Plots - No Notches), causing the controllers to amplify motion at 96.1Hz (see p.4-9 of the attached pdf), and thus to only be stable on their own (see p.2 of the attached pdf).

In order to get HAM2-ISI under active-control, we decided to apply temporary notches on the level-1 controllers of HAM2-ISI. We started with the most unstable controllers: X and RY.
Simulation Plots – Notches on X and RY

After implementing the new X and RY isolation loops, we were able to have all HAM2-ISI controllers running at the same time.  We took comparative spectra for the various configurations of the ISI: not damped, damped and controlled with the new controllers. They showed that the motion of the ISI was still amplified at 96.1Hz (Image #1).

In oder to correct that, we went through all the other controllers of HAM2-ISI and applied proper notches to them. The only one that did not need any was RZ.
Simulation Plots – Notches on all DOF
We then got rid of the excessive motion amplification at 96.1Hz (Image #2). 

HAM2-ISI is now under control Level 1 with the generic 900mHz blend filters ON.

Note 1: HAM2-ISI is loaded with dummy masses only. This control work was made in anticipation of the future Control & Commissioning of the unit, and in preparation of the Control & Commissioning that will soon be performed on HAM3-ISI.
Note 2: The iquiery described above involved looking into te details of the HAM-ISI generic routines, and revealed the need for minor corrections. Routine #7 was corrected twice: SVN revisions 6028 and 6077

IAS looked at the position of the Optical Table and gave us the deltas from perfect.  We looked at the Support Table level and found it level to +-0.1mm.  We did need to shift the payload on the Optical Table however, I had adjusted it to correct the overload I had found in aLOG 4242.  We leveled the Optical Table now to +-0.1mm at an elevation of -200.2mm global, 0.2mm low.
IAS gave us a correction for horizontal of 0.7mmN, 3.1mmE & 369urad cw but I decided not to do this.  We've already pulled the Support Table 5mm east and I'll likely already have to shift some HEPI piers around.  Our position spec for this table is +-3mm and tht was what we told ISC after they gave us a spec of +-6mm so I think we are OK.

Thanks to Scott & Ed

We finally swapped the M3 stage UL AOSEM which had a cracked filter (s/n 242).  The new unit (s/n 212) has an OLV of 26640.  Stuart reset the PR2 M3 UL OSEMINF offset to -13320 and the gain to 1.126.