On Monday, 1/30, Greg and I installed the H2 steering mirror mounting hardware in BSC8.  We found that mounting it on the bottom 3 holes of the BSC flanges, as intended, made the mirror hardware sit on the chamber floor planks.  We also found that the pivot rod,while just long enough to span the chamber and sit in it's mounts at each end, was short enough to allow it to shift and fall out of the mount.  Black marks also came off of Greg's gloves when he installed the viton damping pads.

On Tuesday, 1/31, issues with the install on Monday led me to decide to remove the hardware.  Greg and Thomas worked in the chamber removing the hardware.  They also used IPA and poly wipes to clean the two flanges that came into contact with the viton pads.

Greg G. Jim W. Scott L. Ed
	HAM 3 now has the housings and crossbeams installed. We used the spacers between the base clamp and the crossbeam this time and it worked really well, much better on the clearances. So well that HAM 2 should probably be retro-fitted with them.

Attached are plots of dust counts > .5 microns for today and yesterday. I have included a plot of H0:PEM-LVEA_DST15_MODE to show when the dust monitor at location 15 in the LVEA (in the clean room over BSC8) was disconnected today (the cable came loose).

David Jones was on the schedule today, but he needed to do work down at the EY.  Thomas covered the morning, and I covered the rest of the day. 

• Main activity today was Dome re-installation on BSC8
• Instrument Air FAULTED at EX--this was due to HEPI pump work by Apollo
• Dust Monitors around BSC8 & 7 would have randomly huge peaks during the day (even at lunch time)
• Patrick re-started the EX Weather Station

Today we detatched the telescope/ISC table from the cube, and put the tele/table on a small work table in the EY lab. The tele/table is not that stable, so the Genie is still supporting it.

Tomorrow we'll pick up the 5-axis thing from the VEA, mount that on another Genie, and detatch the cube. It seems that the actual transport will be some time next week.

Note to self:

1. We dropped one vent washer for 1/4-20 bolt of the wire clamp on the floor. Need to find another one.
2. It was very hard to detach wire clamps because the space was tight. It will become worse once we're next to the ERM under the test stand.
3. Not enough garbs at the end station. Will have to bring some for Keita and Dan.
4. Whenever you have to screw/unscrew something over the optics (i.e. when detaching the vertical protection bars for the ISC table), you need to protect the optics from metal dusts as well as tools and screws by making a foil tray (don't forget to double-fold the edge). I can already see that the back side of the periscope mirror has some metal powders.

Testing of coil amplitude parameters for actuating on the L1 stage for the ITMY QUAD was begun today by injecting white noise excitations from 0-1000Hz in the Longitudinal,Pitch, and Yaw DoFs of the L1 stage of H2 ITMY. 

The responses from these excitations were recorded in the L,P,and Y DoFs from the L1 stage and in the respective DoF of the M0 mass.  These initial excitation parameters will be fine-tuned once the chamber is in vacuum, but they confirm our ability to actuate on the L1 stage and measure it's transfer functions to itself and the M0 stage.

THis morning:

- The Apollo crew removed the walking plates at the dome flange.
- Travis and I entered the chamber to resume EQ stop setting
- Apollo craned the dome into place over the stack upstairs
- Covered the QUAD with it's C3 cover when the Apollo crew removed all of the C3 covers above us (the dome flange was now hovering ~2ft above the flange)
- Once the dome was mated to the flange and the "dust had settle for ~15 mins" we uncovered the QUAD and resumed prep work.
- Performed peel of FirstContact of ITMy-HR, N2 filter blow, swab wipe dab-removal of some particulate (see a subsequent alog for details of this)
- Removed most hardware and 2-step stool from chamber
- Betsy left chamber, Thomas and Lisa entered
- Travis, Thomas, Lisa swung ACB back into nominal position and removed stiffeneing hardware
- - Broke a witness plate in the process so a quick cleanup and replacement of new witness plate in the same location
- Took particle count samples from center of chamber
- People swap again, Betsy in, Lisa/Thomas out
- Removed balance of tools/hardware
- Betsy/Travis removed internal Fiber Guards
- Wiped floor from North-to-door, checking for tools/hardware - none found
- Exited chamber
- Leaned in and placed last 3 witness plates in center of chamber

Door replacement preps are underway.

Corey, Greg, Jim, Mitch, Vincent, Hugo

Transfer functions were taken on HAM-ISI Unit #1 with its top mass sitting on a kinematic mounting. The unusual high Q resonances observed above 100Hz are also gone under this configuration. This result tend to confirm that the resonances observed came from the contact between the top mass and the optical table, and not from the ISI itself.

Resonances appeared between 170 and 260Hz when switching to kinematic mounting. They are mostly visible on vertical measurements. These resonances were not here initially, when the top mass was directly sitting on the optical table. They are caused by the changes applied on the boundary conditions of the Top Mass and shall not be associated with the ISI’s mechanical response.

TF comparative plots are attached.

• Pitch: ~1.06 mrad down
  • Desired pitch: 639 µrad down
  • Outside ±100 µrad test stand spec
• Yaw: ~365 µrad CW
  • Desired yaw: 0 µrad
  • Outside ±100 µrad test stand spec
• Longitudinal: 4mm West
  • Outside ±3mm test stand spec
• Horzontal: 0.86mm North
  • Within ±1mm test stand spec, but may be adjusted closer to the desired position
• Vertical: 0.2mm high
  • Within ±1mm test stand spec

ETMy alignment will commence as soon as SUS personnel are available to make the required moves of the quad structure (currently working on closing out BSC08).

(Corey, Greg, Jim, Mitch)

HAMISI#2 was put on the east most Test Stand.  It will get taken apart (to removed the badly machined plates), and re-assembled, and then re-tested.

This afternoon, with the ISI still unlocked from last night, Travis, Cheryl and I:

- Took pix of the chamber cabling/table layout/etc.
- Set FMy EQ stops to ~0.75mm gap settings and locked down all nuts
- Clamped the ITMy and ERM Masses
- Removed the ERM-AR FirstContact
- - Observed lots of particulate, even after continuous filtered N2 flow
- - Took pictures of this particulate for posterity
- - In light of the particulate, decided to stop and discuss moving the dome placement next in the close-out procedure before pulling ITMy-HR FC
- Closed the ring heater
- Placed a few witness plates in the tube sections adjacent to the chamber
- Unlocked the masses - the QUAD was left in full suspension

Garcia is running some diagnostics on the lower OSEM controls on the QUAD tonight.
We await his results, but anticipate pulling the walking platforms and placing the dome on the chamber tomorrow morning.  We would like to resume our in-chamber QUAD/ACB final preps once the dome work has started.

Corey, Eric, Greg, Jim, Mitch, Vincent, Hugo

Unusual resonances were observed above 100Hz on LHO HAM-ISI Unit#1.  GS13 doors and their brackets were not fully bolted and torqued. These mistakes were corrected, however, the resonances observed only disappeared when Viton pads were added under the ISI‘s Top Mass. 

It is possible that the top mass had uneven contact with the optical table causing it to rattle (We could actually hear the mass ring when being hit with an allen key).  

However, we want to make sure that the resonances are not reduced by the couple "Viton+Top mass" behaving as a mass damper. We are currently trying to find out by measuring the ISI's response with its top mass sitting on a kinematic mounting. 

The comparison curves of the TF before, and after, adding Viton pads under the top mass of the ISI are attached.


Note: The picture of the top mass was taken a bit more than a week ago. The balancing masses layout is not as on the picture anymore, but the top mass remained roughly at the same position (slightly re-centered during Viton Pads insertion).

First layer of exterior sheetrock has been laid down. Edges were filled with backer rod and caulked.

Wednesday night at 8pm local time approx, cdsfs0 went into "read only" mode whereby the NFS fie system looked available, but had detected an error and switch to its safe state. Vincent rebooted the machine via phone support from Dave.

Today we power cycled cdsfs0 at 3pm to activate its IPMI management port. Now it will be possible for CDS sysadmin to remotely power this machine.

As part of the h2fw0 crashing every 3 hours problem, I switch which QFS file system the H2 frame writers write to

35W beam

200W beam

This morning we started adjusting out the ETMy reaction chain 1mm high and 2-3mm side-shift.  We removed 2mm from the right Tops Stage blade tip.  This indeed did lower the chain, and reduced the side shift some.  There is still ~1-2mm of side shift.  During these adjustments we also noted a differential roll between the UIM and Top Mass, which Jeff warned us about.  We snooped around at blade tip heights, mass asymetry, and wire lengths.  Hoping that it was possibly a wire length, we decided to swap the left and right wire segments between these stages.  This did not change the side-shift or roll, indicating that the wire lengths are built properly.  We next will visit the blade tip heights (ugh).

(Mark & Slim from Apollo)

Just to give an update on the Staging Bldg Cleanroom issues noted last month.  Last week, the flimsy castors (actually, it was just poorly designed cleanrooms---weak castors not installed securely in thin boxbeam legs) were replaced with much beefier replacements (after seeing cross-section of legs, still wish they were thicker/stronger like the VEA cleanrooms).  Photos are attached.  These were replaced on the two (of four) cleanrooms we move the most down there.

(obviously both of the attached photos should be rotated clockwise 90deg, seems like the alog doesn't like my photos!)

(Corey, Eric, Hugo, Jim)

Investigations continue for the big mechanical resonance peak around 120Hz.  Hugo has given us a rough location of where to look (Somewhere around the H3 GS-13).  On Monday, we pulled out H3 (replaced with mass), but there was no change.  Also on Mon we pulled some walls in hopes of finding anything obvious.  One issue noticed were a pair of 90degree Wall Brackets which were loose (at V3); see attached "photo(3)".  These were torqued down, but the 120Hz peak was still there---Hugo did notice broadband noise reduction in the high frequencies by torquing these brackets down.

On Tuesday, Jim started banging on things to see if he could hear any rattling/ringing.  He noticed a ping when hitting the big Leg Element weight on the Optics Table.  We decided to put some Viton pads underneath it.  Hugo went with a checkerboard pattern ([48] 0.5"x0.5" 0.0625" thick pads); see attached photos....grrrr, the last photo should be flipped, looks fine on my computer before I uploaded.  Waiting to hear how the measurements turned out on these guys.