J. Kissel, A Pele

Not much to say, we've jus gotta start the iteration process. SR3 is rubbing!

J. Kissel, A. Pele, K. Izumi, T. Sadecki

After Bartlett had completed repairs on SR3, we wanted to get PSL IR light into the output arm in order to confirm that alignment had been restored after finding it pitched down after HWS work last week (see LHO aLOGs 12599 and 12609). However, we immediately found no light coming from the input chain. After confirming that all suspensions were in the same location as the last time this temporary bypass path was aligned (circa June 26th 2014), upon going into HAM2 to investigate we found the by-passed IMC beam clipping after IM1, and not making it through the Input Faraday Isolator. 

Suspecting that the temporary by-pass optics had been bumped (they're right on the edge of the table -- see attached layout), we elected to restore the main IMC trans path alignment to check if the bypass path was still co-linear. The trans path alignment had not yet been restored into flashing again after the 2 [mm] move. Thankfully, with the help of the irises on the table, restoring the IMC flashing required no more than a ~900 [urad] adjustment in Yaw. No change in PSL PZT or MC1 was required; unblocking MC1 revealed that we hit the first (in HAM2 just beyond MC1) and 2nd (in HAM3 just in front of MC2) irises, and were only off by an iris radius in yaw. Nice work pusher team!

Once IMC trans path was restored and flashes found, we confirmed that this path was still centered on IMs 1-4, to ensure a good reference path alignment against which to compare the by-pass. Indeed, with the trans path aligned, we found the bypass path was no longer co-linear.

We spent the rest of the evening re-aligning the by-pass path, and the main beam now is re-aligned up to PR3 (beam hits PR3, but PR2 alignment still needs tweaking to be centered on PR3). 

We've confirmed our alignment with the following:
- By-pass beam is co-linear with IMC trans beam up to IM2
- By-pass beam hits reference spot on the wall
- By-pass beam shows up on IM4 trans QPD
- By-pass beam is centered (by eye) on PR2

In order to help see the spot on PR3, we've turned OFF PR3 optical lever (though left the HAM2 ISI oplev ON). We've elected to leave it OFF, such that we can resume where we left off tomorrow morning. MC1 remains *unblocked,* but MC3 has its metal protective shield on to block the main IMC trans path.

Details for the record:
IM4 Trans QPD SUM values:
    ~4 [ct] BLOCKED
   ~50 [ct] UNBLOCKED

Suspended optics alignment values (in [urad]):
     MC1     MC2     MC3    IM1    IM2     IM3     IM4     PRM     PR2    PR3
P   +1254   +542    -550     0    +35849  +14057  -30000 -540.1  -2000  -245.5
Y   -2366   -550   -2557  3786    +5154.7  +5464  -8737  -244.1  +1000  -250.9
    

In order to double check for rubbing after the magnet repair on SR3, undamped/damped tfs were started on the top mass, and will run overnight on opsws1.

J. Kissel, J. McIver

H1 SEI ETMY has been operating in Fully_Isolated since
2014-Jul-07 19:56 UTC,
after a Stage 2 GS13s trip. We requested ETMY to go to DAMPED (and it completed doing so) at 
2014-Jul-10 17:58 UTC

We will leave the chamber as such overnight, in attempt to get a 24 cycle of performance in this state for long-term performance studies.

Please leave SEI ETMY in DAMPED, unless you talk to Jess or Jeff.

Kyle, Gerardo

Preparation for Monday's vent -> Spun turbo up but shut it down shortly thereafter -> pirani card in gauge controller isn't working for some reason so now turbo safety valve won't close when foreline threshold is exceeded -> will swap cards tomorrow and get turbo going then

Locked the ISI so we (w/ Thomas) could do the HAM4 ISI Optical Table Optical Lever alignment.  I left the ISI locked.

I had the EPICS gateway processes for the vacuum subnet* re-read their access security files to add a missing channel prefix to the whitelist.  This is a zero downtime action.

*h0ve-ws, h0ve-cds, h0ve-h1fe

While assessing the IMC alignment for SR work, we (Kissel, Kiwamu, me) noticed a significant amount of scattered light from the transmitted part of the PR3 OpLev beam.  See photos.  It looks to be a bit low of center on PR3 and is scattering off a nice shiny round aluminum piece in the MC REFL periscope directly behind PR3.  Looking for advice on what to do about it.

***********************************************************
QUAD08 model fitting

I ran the model fitting algorithm on QUAD08 to see if any more insight could be gleaned from the measured TFs towards what is causing the error in the 2nd pitch mode. The fitting algorithm is on the svn at:
.../SusSVN/sus/trunk/QUAD/Common/MatlabTools/QuadModel_Fit/QuadPend_GaussNewton_fit_v3_X1QUAD08.m

The results confirm what others have already seen, in that increasing dm or dn (the top mass wire flexure heights relative to the center of mass) makes the model match the measured pitch modes. Specifically, the model says that either

+1.4 mm on dm

or +1.7 mm on dn

equivalently brings the model in line with the measurements. You can also trade offset between one and the other because these two parameters are degenerate in the model. I also changed

h1 = 0

to 

h1 = 2 mm.

h1 is a horizontal front-back shift in the center of mass for the UIM stage. Betsy and Arnaud observed that the pitch adjusters here are pushed far forwards. This parameter reproduces much of the vertical to pitch cross coupling seen the the vertical-vertical and pitch-pitch TFs. It does not influence the mode frequencies.

I put a QUAD08-tuned model on the svn here:
.../SusSVN/sus/trunk/QUAD/Common/MatlabTools/QuadModel_Production/quadopt_wireloop_QUAD08.m


The physical cause of the increased pitch frequencies remains a mystery. Drooping top mass blades would do this, as would improperly seated wire clamps for the top most wires. Since the top mass blades have been replaced without altering the pitch modes, it is unlikely to be those. A 0.15 mm increase in the top wire diameter would also do this, but Arnaud and Betsy checked the wire with calipers and it is correct.


***********************************************************
wireloop model updates


In the process of doing this analysis, I updated the wireloop model on the svn, which was quite out of date. See:
.../SusSVN/sus/trunk/QUAD/Common/MatlabTools/QuadModel_Production/quadopt_wireloop.m

Based on the most recent drawings for the wireloop quad (all metal, wireloop under PUM) I updated
* all mass and inertia values
* 3 of 4 wire lengths: ln, l1, l2  (these were based mostly on previous work with Mark Barton on the fiber quad model updates)
* transverse wire spacings: n3, n4, n5
* and the d values: d2, d3, and d4

The adjustments on the n parameters helped bring roll more in line. The pitch inertias helped pitch a bit as well. The other parameter corrections had little influence on the dynamics, but are at least more representative of the as-built system.

This work also found an error in some of the assembly drawings where the PUM wire clamp was flipped upside down. This has now been corrected in the drawings. The clamps had been installed correctly.


***********************************************************
The attachment shows a comparison of TFs of the original wireloop model, the new wireloop model, the QUAD08-tuned wireloop model, and the QUAD08 measured TFs.

Andres R. & Jeff B. 

   The regluing of the LL magnet/standoff was successfully completed. The repair jig has been removed from HAM5 and the AOSEMs have been remounted. They have been gross aligned. The suspension EQ stops have been released. 

NOTE: Found several Top Mass EQ stops touching the mass, (these stops were not put on for the magnet repair). When I released these stops there was a visible jump movement of the top mass. We will see if this is a contributor to the SR3 pitch misalignment. 

Particle Counts
Before Work:
 In cleanroom cover on: 0.3 = 0, 0.5 = 0, 1.0 = 0
 In chamber cover on: 0.3 = 17, 0.5 = 10, 1.0 = 2

During work:
 In chamber cover off: 0.3 = 46, 0.5 = 27, 0 

After work: 
  In cleanroom cover on: 0.3 = 0, 0.5 = 0, 1.0 = 0
  In chamber cover on: did not get   


 

Day's Activities:

• 8:50am:  HAM5 Oplev alignment work from HAM4 (Thomas)
• 9:00:  HAM5 Magnet Repair (Jeff/Andress)
• Checked that EX & EY SUS/SEI Watchdogs are NOT TRIPPED
• 9:48:  ITMy IAS set up (Jason)
• 10:10 Nathan (SURF) beginning laser work in Optics Lab
• 10:30 Jeff/Andres Done at HAM5 & ready for Viewport installation handoff
• etmy isi changed to be damped only for detchar study
• 10:45:  Apollo installing viewport for output HAM
• 10:48:  PSL went down over 24hrs ago due to Chiller issue (Peter restored)
• 11:54:  HAM5 Oplev alignment (Thomas & Hugh)
• 12:10pm:  LVEA Transitioned to Laser Hazard (for SR3 pitch alignment work)
• 2:15:  Beginning to search for PSL beam in Input HAMs (Arnaud, Jeff, Kiwamu)
• 3:40:  HAM4 oplev work (Thomas & Hugh)

Nathan will work past 4pm in the Optics Lab, but he will be with Dick G ("they will be done by 5").

I was informed this morning that the laser was off, as there was no infrared light showing up on the video cameras.  Went to the diode room and saw that the crystal chiller was indicating a flow sensor error.  The water level was about the same as it was previously, so there were no water leaks.

I turned the crystal chiller on from the PSL Computer, the flow rates indicated were normal.  Turned the laser back on, everything seems okay.  I do not know what triggered the flow sensor error in the first place.

The WHAM5 HEPI was locked for the Septum pull 23 April-- believe it has been locked since that time.

The HEPI Position Sensors (IPS) have been real since 18 April and during these five days I managed to do TFs & other static test.  As I say, these measurements tend to destress the system and shift the IPS readings but the Cartesian numbers tend to not change much as the local shift cancel out in the cartesian basis.  Attached are the cartesian trends and I'll use these values to update the position loop's target.  Remember these channels are calibrated in nano units so the locked drifts and shifts from initial zero are pretty small.

Updated the safe.snap to save these.  The position loops have not been done yet so these can't turned on.  So lots more matlab work and more safe.snaps to go.

Since the platforms are unlocked, closing the loops seems right.  No issues with HEPI.  The ISI drives seem a bit high for level 1 even though I zero'd out the position biases.  THis could just be the purge air or neighboring floor activities.

HAM5 SR3:  magnets found, osems to replace, lock up sus until HAM5 isi balanced.  Most morning locking and BOSEM adjust

• Balance ISI
• Travis/Jeff--working on SR3 for pitch to SR2

BSC3:  rebalanced BSC3 & locked ISI for SUS (ACB swung back)

BSC1 (Travis):  checked ESD cables (some issue), coarse PIT work complete & ready for IAS check, spool out & ready for IAS (will take ~day for set up), really want to determine if a HEPI translation will be needed, because this would be a major schedule hit

EX Vent Prep:  Laser Hazard at EX, Sheila staged for QPD work, EX first cleaning complete (2nd cleaning Fri or Mon), Doors off on Tues, 1st week:  ISC & PCal 2nd week

HAM4 TF:  tripped last night, so will want to run 8hr TF (after Apollo noisy work):  avoid noisy work near HAM4

Output Arm Oplevs:  ready for HAM4/5 retroreflection

Viewport Inspection work brought up with chambers being closed soon.

Business:

• Monday there will be a film crew (Dale)
• Detchar F2F next week
• DetEng Training at 11am & Journal Club of non-SURF presenters at noon

please see attached. only unexpected h1fw0 restarts up to the time the solaris QFS box was power cycled. 

Pulled the covers away from the ISI table.  Attempted to close position loops on HEPI but was not stable in horizontal, decided to leave it off.  After I got the TFs started, I looked again and found the HP L4C blend filter off so this signal was getting through and I'll guess is the problem.  Don't want to stop the TF so I'll check that tomorrow.