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ID Dateup Author Type Category Subject
  3329   Fri Jul 30 02:54:04 2010 KojiUpdate40m UpgradingMore optics installed on the BS table

July 29 Thu [Steve, Alberto, Kiwamu, Koji]

We placed some optics in the BS chamber.
The chambers are ready to be pumped down on Friday once the heavy door is placed.

- Clean room work

  • Engraved two Y2 mirrors and PBS@532nm
  • Engraved three DLC mounts
  • Each of the mounts needs a 3.5 inch post. We found there is no stock of the post in the lab! Also the clamps!
  • Took the posts from the temporarily removed optics although we need to return those optics into the table during the next vent.
  • We should count the # of the mounts and count the needed posts. Posts and clamps can be either a DLC thick post or New Focus pedestal.

- In the chamber

  • The terminal holder was moved as Alberto described
  • The green steering optics were placed as Alberto described
  • Note: the PBS is flipped in the mount (reflection side is back side)
  • The table leveling
  • Releasing EQ stops / Check OSEMs / Adjust OSEMs (BS OSEMs are untouched)

- After closing the chamber

  • The BS OSEM mumbo-jumbo

Quote:

[Koji, Steve, Kiwamu, Alberto]

- This afternoon we installed a few new optics on the BS table: GR_PBS, GRY_SM2, GRY_SM1.

- We pulled up the cables so that we had more freedom to move one of the cable towers farther South.

- Then we re-leveled the table. PRM OSEMs were adjusted to be nominal insertions.

- Koji released the earthquake stops on BS but the readout of the OSEMs was apparently frozen on the MEDM screens.
Initially we thought it was a software problem. a nuclear reboot didn't solve it. We spent the following three hours investigating the cause.
Eventually it turned out that the earthquake stops on BS weren't actually fully released.

We opened the tank and accessed to BS. Releasing the earthquake stops in full solved the issue. The OSEMs readout went back to normal.

 

  3330   Fri Jul 30 09:51:58 2010 kiwamuUpdateGreen LockingRe: waist positon of Gaussian beam in PPKTP crystals

Okay, I guess I understand what you want to know. I did the following steps.

1. calculated the conversion efficiency as a function of the waist size. I found w~50um was the optimum waist.

  Note: the confocal relation Zr = pi * wo^2/(lamba/n) = L/2  gives us almost the same optimum waist. 

elog #2735

efficiency_waist_edit.png

  2.  Did mode matching to get w=50um

elog #2959

elog #3188

PPKTPmode.png

PSL_doubling.png

  3. calculated the offset

elog #2850

mode_in_PPKTP.png 

 4. Moved the ovens

 

Quote:

I thought we cared about satisfying the confocal focusing parameter, that is to say we want to set Zr = 2L_crystal. If Zr changes inside the crystal, this is the number we care about..isn't it NOT the waist size, but the rayleigh range we care about? I am not entirely sure what youre response is saying you did...

  1. Calculate Zr = pi * wo^2/(lamba/n)
  2. Do mode matching to get this wo in free space
  3. Calculate the offset you need to move the oven by using n
  4. Move hte ovens

OR

  1. Calculate Zr = pi*wo^2/(lamba)
  2. Do mode matching to get this in free space
  3. Calculate the offset you need to move your ovens using n
  4. Move your ovens

I guess the waist size would also let me know - are you using 69 um or 53 um waist size?

 

  3331   Fri Jul 30 09:55:34 2010 steveConfigurationVACslow pumpdown has started

Bob and Steve closed BS chamber with the help of the manual Genie lift and the pump down started. The PSL shutter was closed and manual block was placed in the beam path. High voltage power supplies were checked to be off.

Pumping speed ~ 1 Torr/min was achieved at  1/8 of a turn opened roughing valve RV1

Attachment 1: slowpd5hr.jpg
slowpd5hr.jpg
  3332   Fri Jul 30 12:46:38 2010 KojiConfiguration40m UpgradingBS chamber status
Attachment 1: BS_layout_Jul_29_2010.png
BS_layout_Jul_29_2010.png
  3333   Fri Jul 30 14:53:09 2010 steveUpdateGeneralPSL table leg upgrade

Quote:

July
29 Thu BS chamber work: Move cable towers / green steering mirrors / (2 TTs with TT charactrization) / Put the heavy door by 5PM.
30 Fri Pumping down
31 Sat WFS work by Nancy

Aug
1 Sun - 5 Thu WFS work by Nancy
5 Thu PSL Table prep
6 Fri PSL Table prep / Likely to shut down the PSL

9 Mon PSL Table prep / shutting down of the PSL (optional)
10 Tue PSL box Frame lifting
12 Thu PSL table tapping

16 Mon - 17 Tue concrete pouring preparation
19 Thu - 23 Fri Tripod placement
24 Tue - 26 Thu concrete pouring

The PSL table height will be raised to the level of the AP table. This will be done using 6 TMC's Rigid Damped Tripod legs. Their planed positions shown below.

The legs will be grouted to the floor with concrete.

 http://www.techmfg.com/products/floorplatforms/rigiddampedtripod.htm

Attachment 1: psllegs.PDF
psllegs.PDF
  3334   Fri Jul 30 17:24:22 2010 JenneUpdatePEMGuralps back in the 40m

I brought the GUR2 seismometer back from Bridge so I can get some more MC/Seismic data during the next week while we're pumped down, before we start doing things to the PSL table.  Both of the Gur Seismometers are connected back up to the breakout box as of ~3:27pm today.  Alastair still has the handheld controller thing (which I use for mass centering, on occasion), since he'll want the seismometer back in a week or two when I'm done with it.

 

Something is wrong with both X channels of the Guralps.  Alastair claimed that he and Frank didn't do anything bad when they opened up the breakout box, but I am suspicious. 

 

While I'm at it, a reminder that Jan and his SURF student Greg still have the Ranger, disassembled over in Bridge.  They made a note in their elog, but not in the 40m elog when they took it back again.

Whenever you're done with the Mode Cleaner for the next week, please make sure it is locked, nicely aligned and happy before you leave.  Also please make a note of what you're doing and when, so that I know what is good data and what is data with unusual conditions.

In other, semi-bad news (but already recovered from), when I was finishing putting the Guralp Breakout Box back in the rack, I bumped the power strip that is on the top back side of the rack, near the corner that the door opens on (not the corner the door hinges on).  I turned the power strip back on, and I think everything that is connected to it came back okay.  Anyhow, my bad. Sorry. 

  3335   Fri Jul 30 17:52:12 2010 KojiConfigurationGeneralJacket

Jenne and I need our jackets. We removed them from the Rb clock.
Thanks for making them warm.
Probably a Scotland sweater would fit.

  3336   Fri Jul 30 17:54:55 2010 steveHowToVACHow to stop and start slow pumpdown

Quote:

Bob and Steve closed BS chamber with the help of the manual Genie lift and the pump down started. The PSL shutter was closed and manual block was placed in the beam path. High voltage power supplies were checked to be off.

Pumping speed ~ 1 Torr/min was achieved at  1/8 of a turn opened roughing valve RV1

 We are at 370 Torr at 9 hrs of  pumping. RV1 is opened to ~ 3/8 turn orifice. We are using one roughing pump RP3  and butterfly valve is in place.

 

How to stop: 1, close RV1 by torque wheel  2, close V3 from MEDM screen  3, turn off RP3 roughing from MEDM screen  4, disconnect metal hose to oily pump

after butterfly valve. This KF-45 O-ring seal should be kept clean 5, place/close  45 mm cover blanks at the end of the hose and and on the 5" nipple.

 

How to start: 1, remove blanks from  hose and nipple 2, reconnect roughing pump hose to RV1 nipple  3, turn on PR3  4, open V3  5, open RV1 by wrench to ~3/8

6, fine tune RV1 opening to 1 Torr/min

 

ESSENTIAL: one operator has to be present when oilly roughing pump is connected to the vac. envelope

  3337   Fri Jul 30 19:20:15 2010 AlastairConfigurationGeneralJacket

Quote:

Jenne and I need our jackets. We removed them from the Rb clock.
Thanks for making them warm.
Probably a Scotland sweater would fit.

 Thanks for the loan guys.  I do have a lot of warm weather clothing at home that is not so necessary in the California climate.  I will find some suitable attire for the Rb clocks there.

  3338   Fri Jul 30 22:07:42 2010 KojiHowToVACHow to stop and start slow pumpdown

Kiwamu and Koji

The rough pumping was stopped at 230mmTorr. We are going to resume the pumping tomorrow morning.

  • RV1 was closed with torque wheel.
  • V3 was closed from MEDM
  • RP3 wss stopped from MEDM
  • The quick coupling to RP3 was disconnected.

Quote:

    How to stop: 1, close RV1 by torque wheel  2, close V3 from MEDM screen  3, turn off RP3 roughing from MEDM screen  4, disconnect metal hose to oily pump

after butterfly valve. This KF-45 O-ring seal should be kept clean 5, place/close  45 mm cover blanks at the end of the hose and and on the 5" nipple. 

    How to start: 1, remove blanks from  hose and nipple 2, reconnect roughing pump hose to RV1 nipple  3, turn on PR3  4, open V3  5, open RV1 by wrench to ~3/8

6, fine tune RV1 opening to 1 Torr/min

ESSENTIAL: one operator has to be present when oilly roughing pump is connected to the vac. envelope

  3339   Sat Jul 31 04:03:11 2010 GopalSummaryOptic StacksComplete Displacement Translational Transfer Function Matrix

Over the past 36 hours, I've run full-fledged FDAs on KALLO.

The transfer functions for translational drives and responses are neatly described by the attached transfer function "matrix."

Progress_Report_2.png

Next steps:

1) Extend the 3x3 analysis to include tilts and rotations in a 6x6 analysis.

2) Figure out how to do the same types of tests for phase instead of displacement.

  3340   Sat Jul 31 10:12:05 2010 kiwamuUpdateVACRe: How to stop and start slow pumpdown

I resumed the pumping down. It started from 9:55 am.

  3341   Sat Jul 31 14:59:33 2010 kiwamuUpdateVACRe: How to stop and start slow pumpdown

I stopped the pumping at 14:50 pm because I was going back home. I did the same procedure as Koji wrote down (see here).

The P1 pressure reached 32 Torr.

Koji will take over the pumping shift tonight. 

  3342   Sat Jul 31 17:37:36 2010 josephbUpdateCDSCables needed for CDS test

Last Thursday, Kiwamu and I went through the cabling necessary for a full damping test of the vertex optics controled by the sus subsytem, i.e. BS, ITMX, ITMY, PRM, SRM.  The sus IO chassis is sitting in the middle of the 1X4 rack.  The c1sus computer is the top 1U computer in that rack.

ADCs:

The hardest part is placing the 2x D-sub connectors to scsi on the lemo break out boxes connected to the 110Bs.  The breakout boxes can be seen at the very top of the picture Kiwamu took here.  These will require a minor modification to the back panel to allow the scsi cable to get out.  There are two of these boxes in the new 1X5 rack.  These would be connected by scsi to the ADC adapters in the back of the sus IO chassis in 1X4.  The connectors are currently behind the new 1X5 rack (along with some spare ADCs/DACs/BOs.

There are 3 cables going from 40 IDC to 37 D-sub (the last 3 wires are not used and do not need to be connected, i.e. 38-40).  These plug into the blue and gold ADC adapter box, the top one shown here.  There is one spare connection which will remain unused for the moment.  The 40 IPC ends plug into the Optical Lever PD boxes in the upper right of the new 1X4 rack (as seen in the top picture here - the boards on the right). At the back of the blue and gold adapter box is a scsi adapter which goes to the back of the IO chassis and plugs into an ADC.

In the back of the IO chassis is a 4th ADC which can be left unconnected at this point.  It will eventually be plugged into the BNC breakout box for PEM signals over in the new 1X7 rack, but is unneeded for a sus test.

DACs:

There are 5 cables going from 3 SOS dewhite/anti-image boards and 2 LSC anti-image boards into 3 blue and gold DAC adapter boxes.  Currently they plug into the Pentek DACs at the bottom of the new 1X4 rack.  Ideally we should be able to simply unplug these from the Pentek DACs and plug them directly into the blue and gold adapter boxes.  However at the time we checked, it was unclear if they would reach.  So its possible new cables may need to be made (or 40 pin IDC extenders made). These boxes are then connected to the back of the IO chassis by SCSI cables.  One of the DAC outputs will be left unconnected for now.

Binary Output:

The Binary output adapter boxes are plugged into the IO chassis BO cards via D-sub 37 cables.  Note one has to go past the ADC/DAC adapter board in the back of IO chassis and plug directly into the Binary Output cards in the middle of the chassis.  The 50 pin IDC cables should be unplugged from XY220s and plugged into the BO adapter boxes.  It is unclear if these will reach.

Timing:

We have a short fiber cable (sitting on the top shelf of the new 1X3 rack) which we can plug into the master timing distribution (blue box located in the new 1X6 rack) and into the front of the SUS IO chassis.  It doesn't quite make it going through all the holes at the top of the racks and through the cabling trays, so I generally only plug it in for actual tests.

The IO chassis is already plugged into the c1sus chassis with an Infiniband cable.

 

So in Summary to plug everything in for a SUS test requires:

  • 6x SCSI cables (3 ADC, 3 DAC) (several near bottom of new 1X3 rack)
  • 4x 37 D-sub to 37 D-sub connector (end connectors can be found behind new 1X5/1X6 area with the IO chassis stuff - Need to be made) (4 BO)
  • 3x 40 IDC to 37 D-sub connectors (end connectors can be found behind new 1X5/1X6 area - Need to be made)(ADC)
  • 5x 64 pin ribbon to 40 IDC cable (already exist, unclear if they will reach) (DAC)
  • 8x 50 pin IDC ribbon (already exist, unclear if they will reach) (BO)
  • 1x Double fiber from timing master to timing card
  • 1x Infiniband cable (already plugged in)

Tomorrow, I will finish up a channel numbering plan I started with Kiwamu on Thursday and place it in the wiki and elog.  This is for knowing which ADC/DAC/BO channel numbers correspond to which signals.  Which ADCs/DACs/BOs the cables plug into matter for the actual control model, otherwise you'll be sending signals to the wrong destinations.

WARNING: The channel numbers on the front Binary Output blue and gold adapter boxes are labeled incorrectly.  Channels 1-16 are really in the middle, and 17-32 are on the left when looking at the front of the box.  The "To Binary IO Module" is correct.

  3343   Sat Jul 31 22:35:01 2010 KojiUpdateVACVac-P1 still 1.2mtorr

I resumed the pumping from 19:00.

Now the valve RV1 is full open. But the pumping is really slow as we are using only one RP.

After 3hrs of pumping, P1 reached 1.2mmtorr but still we need 2hrs of pumping...

I stopped pumping at 22:30.

  3344   Sun Aug 1 18:50:35 2010 KojiUpdateVACP1 = 0.48 torr

I resumed the pumping today. Now the pressure is 0.48 torr. The pump was stopped.

Quote:

I resumed the pumping from 19:00.

Now the valve RV1 is full open. But the pumping is really slow as we are using only one RP.

After 3hrs of pumping, P1 reached 1.2mmtorr but still we need 2hrs of pumping...

I stopped pumping at 22:30.

 

  3345   Sun Aug 1 21:04:45 2010 ranaSummaryComputer Scripts / ProgramsMC Autolocker fixed

Someone had left a typo in the MC autolocker script recently while trying to set the lock threshold to 0.09. As a result, the autlocker wouldn't run.

I repaired it, made a few readability improvements, and checked in the new version to the SVN. If you make script changes, check them in. If you think its too minor of a change for a SVN checkin, don't do it at all.

  3346   Sun Aug 1 21:40:27 2010 ranaSummaryPSLFSS: SLOWDC response

I bet you thought that the NPRO slow actuator response could be well represented by a pole at ~0.1 Hz? Well, that's just what they want you to believe.

I attach the response measured in FSS-FAST (with no feedback to the SLOW actuator) when the SLOW is given a step. As you may remember from

kindergarten, the response of a single pole low pass should just be an exponential. Clearly, there's more here than 1 pole.

 I also inserted a factor of 0.01 in the FSSSlowServo code so I could make the gain sliders have reasonable values (they used to all be ~1e-3). The SVN and the MEDM snapshot are updated.

Attachment 1: Untitled.png
Untitled.png
  3347   Mon Aug 2 10:26:15 2010 steveConfigurationVACvery slow pumpdown completed

Quote:

Bob and Steve closed BS chamber with the help of the manual Genie lift and the pump down started. The PSL shutter was closed and manual block was placed in the beam path. High voltage power supplies were checked to be off.

Pumping speed ~ 1 Torr/min was achieved at  1/8 of a turn opened roughing valve RV1

 3 days pump down #69 completed. Thanks to Koji  and Kiwamu  who did more roughing on Saturday and Sunday.

Attachment 1: veryslowpd.jpg
veryslowpd.jpg
  3348   Mon Aug 2 17:12:28 2010 KojiUpdateGeneralLab schedule for the week of Aug. 2

Aug

2 Mon - 5 Thu WFS work (Nancy)

2 Mon - 4 Wed

Jenne: Seismometer fix / Seismic measurements on the PSL table
TT characterization (with Koji)
Preparations ETM suspensions (optional: may be in later weeks)

Kiwamu: CDS test for SUS (may be involving Koji)

Alberto: RF system prep.

All: For 5th and 6th: PSL cabling works Koji

5 Thu PSL Table prep
6 Fri PSL Table prep / Likely to shut down the PSL

9 Mon PSL Table prep / shutting down of the PSL (optional)
10 Tue PSL box Frame lifting
12 Thu PSL table tapping

16 Mon - 17 Tue concrete pouring preparation
19 Thu - 23 Fri Tripod placement
24 Tue - 26 Thu concrete pouring

Attachment 1: PSL_work_schedule.pdf
PSL_work_schedule.pdf
  3349   Mon Aug 2 18:02:46 2010 JenneUpdatePEMSeismometer Update: Still not good, but perhpas getting better

Today's seismometer diagnosis activities are still underway, this is just an update (since I did some reboots):

Problem 1: X and Z channels on both seismometers were flipped.  I unplugged an X cable (East/West on the cable labels) and the Z channel (vert) would go to floating ADC zero.  Rana suggested that the ADCs sometimes have random channel hopping, and that a reboot of the c0dcu1 computer which handles the PEM ADCU should fix this problem.  I keyed the c0dcu1 / c0daqawg crate, those computers came back just fine, and the channels were no longer flipped.  This is a good thing.  Although now it's actually the Z channels that were / are bad on both seismometers, not the X's.

While rebooting those computers, c1iovme, c1sosvme, c1susvme1 and c1susvme2 crashed.  I rebooted them, although for the first few power cycles c1susvme1&2 couldn't mount /cvs/cds/caltech.  Eventually they did, and life is good again.  Except that the seismometers are still funny.

  3350   Mon Aug 2 21:52:57 2010 KojiUpdateIOOMC is running at the full power

[Nancy and Koji]

We restored the full power operation of the MC.

Restoration of the suspensions

  1. Found the suspension watch dogs are left turned off.
  2. Found c1susvme1/2 were not running.
  3. Launched the realtime processes on c1susvme1/2 and c1iscey
  4. Restored the watch dogs. The suspensions looked fine.

Preparations for the high power

  1. Put an ND2.0 before the MCT CCD. Confirmed the ND reflection is damped.
    MCT QPD is not necessary to be touched.

The high power operation of the MC / post lock adjustment

  1. Locked the MC under the autolocker being disabled.
  2. Adjusted the aperture on the MC2 face camera
  3. Adjusted the spot positions on the WFS QPDs
  4. Reverted the scripts to the high power ones
    (mcup / mcdown / autolockMCmain40m)
  5. Logged in to op340m and restarted autolockMCmain40m

The autolocker seems working correctly.

  3351   Tue Aug 3 01:51:01 2010 JenneUpdatePEMSeismometer Update: Still not good, but perhaps getting better

Quote:

Today's seismometer diagnosis activities are still underway, this is just an update (since I did some reboots):

Problem 1: X and Z channels on both seismometers were flipped.  I unplugged an X cable (East/West on the cable labels) and the Z channel (vert) would go to floating ADC zero.  Rana suggested that the ADCs sometimes have random channel hopping, and that a reboot of the c0dcu1 computer which handles the PEM ADCU should fix this problem.  I keyed the c0dcu1 / c0daqawg crate, those computers came back just fine, and the channels were no longer flipped.  This is a good thing.  Although now it's actually the Z channels that were / are bad on both seismometers, not the X's.

While rebooting those computers, c1iovme, c1sosvme, c1susvme1 and c1susvme2 crashed.  I rebooted them, although for the first few power cycles c1susvme1&2 couldn't mount /cvs/cds/caltech.  Eventually they did, and life is good again.  Except that the seismometers are still funny.

 Some more progress, but still not complete:

Jan and I looked at all of the Gur channels on a 'scope (battery, so as not to be grounded), and 5 of the 6 looked good.  We were looking at the BNCs just as they go into the ADC.  The one which still looks bad is Gur1Z.  The 'scope just doesn't see any signal on that channel. 

In addition, the ADC's BNC input #4 (which normally has Gur2Z) looks totally shot.  When it's floating, the signal on dataviewer definitely doesn't look floating.  I'm probably going to have to move over to another channel, and just give that one up (this ADC already has several channels which have been declared bad, so maybe it's not a surprise that this can happen?)

Since one of the Gur signals looks bad (Gur1Z) and one of the ADC channels looks bad (usual Gur2Z), I switched the Z channels on the ADC board, so the channel being saved as Gur1Z is in fact Gur2Z.  This is valid as of ~1:15am until further elog notice.

During my investigations into why Gur1Z is funny, I also looked at the signal on the BNC octopus cable coming straight from the output of the Guralp Breakout Box (this is the cable which goes from "ADC Out" on the back of the box which is a 37 pin D-sub to 9 differential BNCs), and sometimes I saw zero on the 'scope, but sometimes there was a signal which would coincide with jumping tests.  Whenever there was a signal however, it was always a way lower amplitude (at least by a factor of 10?) than the other channels.

All of this craziness led to me pulling the Guralp box to investigate. 

Upon opening the box, I recalled that the channels go in order: Vert, NS, EW.  The Gur1Z channel is that first vert channel, and it's the one which always had a blue input capacitor rather than a surface mount one.  Being suspicious of Frank and Alastair, since they seemed unhappy with my capacitor choices, I wondered if they had wiggled the blue cap, and tore something loose.  Just in case, and to make things seem more uniform, I replaced the blue cap with a surface mount 1uF cap.  (Actually its 0.909uF, replacing the 0.905uF blue cap, according to the black DMM that measures capacitance.) While I was in there, since it had been a problem in the past (elog 2811), I relflowed the solder on some of the resistors, especially near the output op amp. 

Anyhow, none of that may have been necessary.  All 6 of the Gur channels were examined on a 'scope, using clip doodles to measure the various Test Points on the circuit.  I looked at all of the TPs in Gur1Z, and I didn't find that any particular stage was any noisier than the others.  Also, all 6 of the Gur channels seemed totally fine in terms of sending a good signal to the output of the box, including Gur1Z which is currently under investigation.  All of the channels passed the "output looks ~20x the input" test, and for approximately equal thumping on the ground all 6 channels seemed to have similar amplitude outputs.  The Z channels on both channels one and channels two were a little bigger than the X's or Y's, but the 2 Z channels were about the same.  This test was done using Guralp2 and the Gur2 cable on both channels 1 and 2, and then checked with Guralp 1, using the Gur2 cable on channels 1.  The Vert1 channel always seemed good.

I now am suspicious of one or more of the cables: either the Gur1 cable from the seismometer to the box, or the Vert1 channel of the octopus cable.  I'm satisfied that the BNC cables running through the cable tray are okay (although it might not hurt to check that they all successfully send a sine wave...)  I opened up the backshell of the Gur1 cable, on the end that connects to the breakout box.  Nothing seemed amiss.  I still need to Beep the cable to check its connections, and look at the octopus cable. 

Recap / Current Status:  Breakout Box is reinstalled, both seismometers hooked up.  The Z channels on the seismometers are swapped at the ADC input. The dataviewer channels Gur1_X, Gur1_Y, Gur1_Z (which is actually Z of Gur2 seismometer) and Gur2_X, Gur2_Y are all good.  Nancy is going to leave the MC in a happy place, and note the time when she's done. Tomorrow I'll check out the cables for the Gur1Z seismometer channel. 

  3352   Tue Aug 3 03:15:06 2010 nancyUpdateIOOMC back to locked mode

I turned the WFS gain to 0.02 back, and the MC is locked, the data for the seismic motion might be meaningful nowforth.

  3353   Tue Aug 3 11:17:10 2010 kiwamuUpdateCDSDiagrams for Cables needed for CDS test

Current Wiring Setup for the Suspension Controls

sus_wiring.png

New Wiring Plan for the Suspension Controls  with the New CDS  

sus_new_wiring.png

Missing Stuff for the CDS test

Ideally we can reuse the existing cables, but some of them may not be long enough for the new wiring.

The diagram below shows extremely non-ideal case.

sus_missing_stuff.png

Some more information will be summarized on the wiki later.

 

  3354   Tue Aug 3 11:50:16 2010 JenneUpdatePEMSeismometer Problem Tracked down

After some cable swapping this morning, I have determined which cable is bad.  It's the Gur1 cable between the seismometer and the breakout box.  This is a milspec -> 37pin d-sub cable.  I'll pull out the cable and have a look at it after lunch.

  3355   Wed Aug 4 01:44:56 2010 KojiConfigurationPEMAccelerometer located on and below the PSL table

[Jenne and Koji] 

In order to characterize the seismic vibration of the PSL table, we put the accelerometers on and below the PSL table.

On the PSL: MC2 Accelerometers (X, Y, Z) - being connected to CH1-3 of the preamps
East side of the PSL table. X, Y, and Z is directed to North, East, and Up.

On the ground: MC1 Accelerometers (X, Y, Z) - being connected to CH4-6 of the preamps
Beneath the West side of the PSL table. X, Y, and Z is co-aligned to the MC2 ACC.

I found that the C1:PEM-ACC_MC1_Z has large noise in the low freq (~1Hz) region. I tracked down the noise source
and found the noise is still present in the down stream even when the CH17 (C1:PEM-ACC_MC1_Z) of the ADC IF BNC
(@1Y7) was terminated.

I consulted with Jenne and decided to connect this channel to CH14, which is vacant and has name
C1:PEM-AUDIO_MIC2 (16k).
(for the details of the channel configurations, see /cvs/cds/caltech/chans/daq/C1ADCU_PEM.ini)

I first tried magnetometer channels to steal, but they didn't seem reacting (and the connected to the wrong channels).
I am feeling that we should once entirely check the I/F box.

Note that there looks the difference of the gain by x10 between C1:PEM-ACC_MC* channels and C1:PEM-AUDIO_MIC2.

[From Jenne:  The gain difference is because the C1:PEM-ACC_MC* channels have gain=10 in the .ini file, while C1:PEM-AUDIO_MIC2 uses the default gain=1. ]

Attachment 1: IMG_2675.jpg
IMG_2675.jpg
Attachment 2: IMG_2678.jpg
IMG_2678.jpg
Attachment 3: IMG_2682.jpg
IMG_2682.jpg
  3356   Wed Aug 4 03:01:56 2010 JenneUpdatePEMCatastrophic Cable Failures

Quote:

After some cable swapping this morning, I have determined which cable is bad.  It's the Gur1 cable between the seismometer and the breakout box.  This is a milspec -> 37pin d-sub cable.  I'll pull out the cable and have a look at it after lunch.

 So, I was wrong about which cable it was, probably in my rush to get some lunch.  The actual culprit was the octopus cable that Bob made waaay back in the day (~2 years ago) to go from the "ADC out" of the breakout box (37pin Male Dsub) to 9 BNCs.  As it turns out, the Gur1Z channel of that cable was broken on both ends!!! 

On one end, we have the 37 pin Dsub.  The cable used was so thick (way too thick for this application) that it made a super rigid connection between the wires and the connector, and any bending of the cable stressed this connection, despite the strain-relief of the backshell.  The Gur1Z connection snapped off when I was gently wiggling the connections to check them out.  Also, since the wires were all so thick, they didn't really fit into the hole in the backshell, so 2 or 3 of them were squished.....straight through the insulation so that several channels were shorted together / potentially shorted to ground.  This may explain some of the nasty behavior that Rana and I had seen (although I might have forgotten to elog? My bad.) that even with the inputs of the breakout box all terminated, there was high coherence between the channels.  Terminated inputs should give random noise, so this was fishy. 

On the other end of the cable we have the 9 BNCs.  I had finished redoing the 37pin end of the cable, and was 'beeping' it to check it out, when to my dismay I found that the Gur1Z channels (the inside and the outer shield of the BNC connector) were shorted together.  I removed these 2 wires from the Dsub connector to confirm that the BNC was at fault.  Koji looked at the BNC with me after I chopped it off of the cable.  Bad news strikes again.  To get the wires to fit in the inner pin of the BNC connector, the cable-maker had cut off several strands of the wire to make it skinnier.  It appears that over the years these cut-off strands wiggled their way to touching the outer shield.  This appears to be a danger for all of the BNCs on this cable: a little bit of torque (which one might expect during plugging and unplugging a BNC) and the 2 sides of the differential measurement will be shorted together.

I then decided to start afresh and make my own cable.  I found some AWG26 8-twisted-pair cable laying around underneath the Yarm (since this was all I could find, I was just going to do the Gur1 and Gur2 channels, and leave out the Gur3's).  The 37 Dsub side was easy, but I seem not able to connect such skinny wire to the BNC connectors in a robust way.  Since this bad cable has so far cost me ~2.5 16-hour days of grief, I don't want my new version of it to also be bad.  At this point, I await the advice of one wiser than I. I think BNC connectors are designed for something a little closer to ~20AWG, but I could be wrong.  Also, they are obviously optimized for coax cable. So what I have now is never going to be great.  Maybe tomorrow I can go to the Electronics Shop / Store and buy BNC connectors that are meant to be soldered-to.  That would be awesome.

Since I currently have no functional cable to go from Breakout box to ADC, the Guralps are unplugged for tonight.

Conclusions for the day / evening:  Frank, Alastair and Jenna are mostly absolved of blame, although the traveling to Bridge and opening and closing the box (which usually involves more plugging and unplugging of cables) probably didn't help this cable out too much.  Also, Bob definitely owes me a Sugar Napoleon or something.

 In other news, since the Gur2Z ADC channel is totally wacked, I have taken over (but not renamed) the Ranger channel for Gur2Z for now.  Jan still has the Ranger hostage over in Bridge, so this is okay for now.

  3357   Wed Aug 4 11:10:28 2010 nancyUpdateIOOMode Cleaner WFS

Yesterday, I started twiddling with the Mode Cleaner at about 2 pm.

So the seismic data should be all good before that.

I was using it till about 3.30 am, and then left for the night with locking it and swithcing on back the WFS control

Today morning, I have started twiddling with it again, at about 10.30 am.

 

About my work with the mode cleaner :

 

I am primarily exciting the mirrors in pitch and yaw, and trying to measure the response of the WFS and the MC2 OPLEV wrt the excitation.

This thus involves switching off the WFS control while measurement.

After two more of those measurements today, I will get to finding new values for the Output Matrix of the WFS for controlling MC1 & 3, and also, try giving in control to MC2 alignment using OPLEV signals.

 

  3358   Wed Aug 4 12:49:42 2010 nancyUpdateIOOMode Cleaner WFS

Quote:

Yesterday, I started twiddling with the Mode Cleaner at about 2 pm.

So the seismic data should be all good before that.

I was using it till about 3.30 am, and then left for the night with locking it and swithcing on back the WFS control

Today morning, I have started twiddling with it again, at about 10.30 am.

 

About my work with the mode cleaner :

 

I am primarily exciting the mirrors in pitch and yaw, and trying to measure the response of the WFS and the MC2 OPLEV wrt the excitation.

This thus involves switching off the WFS control while measurement.

After two more of those measurements today, I will get to finding new values for the Output Matrix of the WFS for controlling MC1 & 3, and also, try giving in control to MC2 alignment using OPLEV signals.

 

 TFs after the measurement -

 In the order - MC1 , MC2 , MC3 -pitch and yaw.

These plots let us know about how do the wavefront sensor signals actually respond to the mis-alignments in the mirrors.

For legibility, legend has been includded in only one plot in each pdf., its typically the same for all  3 plots.

the actual xml files for this measurement are in the directory /cvs/cds/caltech/users/nancy/Align_Matrix/highpower/spot_center

It was made sure before each measurement that the MC is best aligned, the WFS are turned off, and the spots on all 3 QPDs are centered.

 

Attachment 1: pit.pdf
pit.pdf
Attachment 2: yaw.pdf
yaw.pdf
Attachment 3: pit.pdf
pit.pdf
Attachment 4: yaw.pdf
yaw.pdf
Attachment 5: pit.pdf
pit.pdf
Attachment 6: yaw.pdf
yaw.pdf
  3360   Wed Aug 4 16:52:59 2010 Razib, AidanUpdatePhase CameraSideband power measurement (updated)

Aidan and I made some attempt to measure the power of the sidebands so that we can calculate our expected signal strength.

Our setup looks like the following:

Setup_08_04_2010.jpg

 

As light from the laser is split into two at BS1, the transmitted beam has higher power as our BS1 is only coated for 1064nm. We get two reflected beams from BS1, one reflected of the front surface and the other from the back surface. We took the stronger back reflected beam to the EOM driven at 40 MHz (also at 25 MHz at  a later time). The AOM produced a reference beam with 40 .000 005 MHz offset which we recombined with the sidebands obtained from the EOM. The beat produced is sent off to PDA 10CF connected to 4395A spectrum analyzer.

The plots for 40MHz sidebands and 25 MHz sidebands looks like this:

power_40MHz.png

From the above spectra, at 40 MHz sideband regime:

Power of the carrier @ 40 MHz = -39.72 dBm

Power of the sideband @ 80 MHz = -60.39 dBm

 

 

power_25MHz.png

At 25 MHz sideband regime,

Power of the carrier @ 40 MHz = -40.22 dBm

Power of the upper sideband @ 65 MHz = -61.72 dBm

Power of the lower sideband @ 15 MHz = -60.99 dBm

 

Power Measurement:

We made some necessary power measurement using a PD connected to a voltmeter after the EOM and the AOM when the EOM is driven at 40 MHz:

___________________________________________________________

Dark :  0.025 V

AOM on: 4.10 V    (EOM blocked)

EOM : 2.425 V      (AOM blocked)

___________________________________________________________

 From the earlier calculation (ref: Elog entry July 28) the power that we expect to see at the PD is,

P= A_c ^2 + A_r^2 + A_(-sb)^2+ A_sb ^2 +2* A_r* A_sb * cos ( w_(r,sb) t ) ,                         where A_c= carrier;   A_r= reference beam;     A_sb=Upper sideband;    A_(-sb)= Lower sideband,     w_(r,sb) = w_r - w_sb

P = A_c ^2 + A_r^2 + A_(-sb)^2+ A_sb ^2 +2* A_r* A_sb  , letting cos (w_(r,sb) go to 1) is order to approximate the maximum signal

So the signal that we expect to see relative to the DC ( i.e    A_c ^2 + A_r^2 + A_(-sb)^2+ A_sb ^2,    the first four terms of the power equation) is,

Sig = 2* A_r* A_sb    / { A_c ^2 + A_r^2 + A_(-sb)^2+ A_sb ^2 },

Since the modulation index is small, the power in the sideband is very small compared to carrier and the reference beam. So we can ignore the sideband power for the signal expression.

So,

Sig = 2* A_r* A_sb  /  ( A_c ^2 + A_r^2 )

So if we want to maximize this signal w.r.t the reference then,

d (sig)/ d(A_r) = 2 { ( A_c ^2  - A_r^2) *A_sb } / {( A_c^2 + A_r^2)} ^2

Thus, the signal is maximized when,

A_r^2 = A_c^2

 

We adjusted the AOM to be driven at + 7.7 dBM so that the new power at the AOM matched the EOM power, which is 2.397 in the voltmeter.

So the power at both the AOM and the EOM are:

P_AOM = ( V_AOM - V_dark) / (PD responsitivity * Transimpedance gain)

               = ( 2.397 - 0.025 ) / ( 0.45  * 1.5 x 10 ^5 )

               = 3.51 x 10 ^ - 5  W

P_EOM = (V_EOM - V _dark) / (PD responsitivity * Transimpedance gain)

               = ( 2. 425 - .0.025) / ( 0.45 * 1.5 x 10 ^5 )

               = 3.55 x 10^ - 5  W

 

From the spectra of the 40 MHz sideband above, the ratio of the carrier and the sideband amplitude is:  A_c / A_sb = 10.8 .

P_EOM = A_c ^2 + 2 A_sb ^2

Therefore, A_sb = sqrt ( P_EOM / 118.64) = 5.47 x 10^ - 4   V/m

Thus,     A_c = 5.908 x 10^ -3   V/m

and    A_r = sqrt ( P_AOM) = 5.92 x 10 -3    V/m.

 

This measurement can be used to calculate the signal to contrast ratio (SCR) that we expect to see:

SCR = 2 A_r * A_sb  / ( A_c^2  + A_r^2 )  = 0.09

 

Our next step is to measure the actual signal to constrast ratio as seen by the camera. Details of that will be posted soon.

  3361   Wed Aug 4 19:50:58 2010 ranaConfigurationElectronicsRubidium clocks too hot: hut removed

Alastair found that the foam hut that he and Jan put on top of the Rb clocks to temperature stabilize them was too good of an insulator. The Rb boxes had gotten very hot and became internally unlocked as seen on the front panel.

After we let them cool down with the box off, I turned them back on. After several minutes the 'Locked' light came back on. Some minutes after that the '1PPS Sync' light also came on, indicating that the two had become somewhat synchronized. It really means that the frequencies are kind of close: I think its roughly that f1-f2 < 2 mHz.

I put the yellow box back on and have left it with a small gap on the bottom so that the hot air can get out. Hopefully, this will protect the clocks from the wind, but not cause them to overheat.

The signal going to the DAQ right now is DC-coupled, with a gain of 1. The peak-peak beat signal in this situation is 6300 counts.

My guess is that the clocks will by synchronized by tomorrow afternoon so that we can get the measurement done. Please don't disturb the clocks or the yellow box around them. Try to minimize any activity around that area.

Attachment 1: beat.png
beat.png
  3362   Wed Aug 4 20:15:07 2010 JenneUpdatePEMYay! Guralps work again!

After much hassle, the Guralp cable from the ADC Out of the breakout box to the ADC is fixed, and everything is plugged in and working again.  The seismometers are back in their regular positions at the ends of the MC, ready for some excellent seis/MC combo data. 

I solidified the change of putting the Gur2Z channel into a different BNC input on the ADC.  The C1ADCU_PEM.ini file has been changed so that what used to be the Ranger's channel is now recognized as Gur2Z. 

Also, I changed the same .ini file to reflect Koji's move of ACC_MC1_Z to the old AUDIO_MIC2 channel, so now all 6 Accelerometer channels have the same calibrations again.

Another big change is the change from old-left-handed convention to new-right-handed convention.  The seismometers are aligned the same way they always have been (with the North-South markers aligned with the MC), but now the North-South output is plugged into the BNC on the ADC that is associated with Gur*_X, and the East-West output is plugged into the ADC channel associated with Gur*_Y.  This is true for both Guralp Seismometers. 

So, now we have:

Gur1_X = Gur1_NS = ADC#10

Gur1_Y = Gur1_EW = ADC#11

Gur1_Z = Gur1_Vert = ADC#12

Gur2_X = Gur2_NS = ADC#2

Gur2_Y = Gur2_EW = ADC#3

Gur2_Z = Gur2_Vert = ADC#24

SEIS_Ranger_Y = no longer in the .ini file

  3363   Wed Aug 4 20:58:22 2010 GopalUpdateWIKI-40M Update7.28.10 - 8.4.10 Weekly Update

Summary of this week's activities:

7/28:    Finished Y-Translational 4-Stack Analysis

"Tapered Cantilever" COMSOL tutorial

Tried (and failed) isolating gravity from oscillation

7/29:    Developed tilt/rotation load combinations for torsional inputs and showed these to work in the model

Tried using Normal Vector mode on top plate to obtain output tilts; worked for the rectangular bar, but not for the full stack

Talked to Jan about a 1st-order alternative to gravity - requires Weak Form (only found in COMSOL 3.5 right now)

Began Z-Translational 4-Stack Analysis -- Ran Overnight

7/30:    Progress Report 1st Draft

Completed Z-Translational 4-Stack Analysis

8/1:      Progress Report 2nd Draft

8/2:      Progress Report 3rd Draft

Submitted Progress Report

8/3:      Finalized Eigenfrequency Analysis for MC1/MC3 Stack

24 Physical Eigenmodes plotted and recorded, as expected

Should be good enough for the final report --> focus on transfer function analysis for the remainder of the SURF

8/4:      Prescribed Displacement Tests on Simple Rectangular Block --> shown to better produce displacement-displacement transfer functions

X-to-X Transfer Function seems much better when plotted

Should now be able to do the Displacement portion of Transfer Function Analysis on MC1/MC3 for Translational Modes

(I apologize that this update is a little late)

  3364   Thu Aug 5 00:17:41 2010 KojiUpdatePSLPSL preparation work

We start the work on the cables at around the PSL table.

Aug 5th 10am-4pm?: (Kiwamu, Alberto, Koji)
- Removal of the unused cables around the PSL table and the control room
- Removal of the cable ties on the PSL frame

- Removal of the big nuts at the side of the PSL table

Aug 6th 10am-4pm?: (Kiwamu, Alberto, Koji, Jenne (~noon) )
- Labeling of the cables
- Planning of the disconnection

Aug 9th  9am-5pm: (Steve, Jenne, Alberto, Koji)
- Shutting down of the PSL
- Disconnection of the cables
- Draining of the cooling water
- Removal of the accelerometers
- Removal of the PSL chamber
- Sealing of the table with the plastic sheets

  3365   Thu Aug 5 01:29:39 2010 nancyUpdateIOOMode Cleaner WFS

 

I calculated the MC1&3 Vs WFS1&2 Output Matrix today from the above measurements with koji's help.

the matrix can be generated from the m file at /cvs/cds/caltech/users/nancy/Align_Matrix/matrix.m

these values were put in, and the direction of control is sort of confirmed. I tried twiddling with the gains in the loop to get a 4*4 stable control, but could not succeed.

the mode cleaner is back locked now, and WFS matrix as well as gains are reverted to the old values.  (1.30 am)

 

The output Matrices are

Pitch

0.724
0.197
0
0
-1.448
-0.758

Yaw

0.919
0.139
0
0
-0.0106
-0.1245

 

  3366   Thu Aug 5 11:48:52 2010 nancyUpdateIOOMode Cleaner WFS

Quote:

 

I calculated the MC1&3 Vs WFS1&2 Output Matrix today from the above measurements with koji's help.

the matrix can be generated from the m file at /cvs/cds/caltech/users/nancy/Align_Matrix/matrix.m

these values were put in, and the direction of control is sort of confirmed. I tried twiddling with the gains in the loop to get a 4*4 stable control, but could not succeed.

the mode cleaner is back locked now, and WFS matrix as well as gains are reverted to the old values.  (1.30 am)

 

The output Matrices are

Pitch

0.724
0.197
0
0
-1.448
-0.758

Yaw

0.919
0.139
0
0
-0.0106
-0.1245

 

 I realised today morning that there was a flaw in my calculations for the yaw matrix.

Correcting the values, and also making teh tables more readable.

I will test these values once our computers are back to working condition.


PITCH
WFS1
WFS2
MC1
0.724
0.1964
MC2
0
0
MC3
-1.4436
-0.756


YAW
WFS1
WFS2
MC1
0.0710
0.1074
MC2
0
0
MC3
0.0082
-0.962

 

 

  3367   Thu Aug 5 13:05:53 2010 KojiUpdateIOOMode Cleaner WFS

Upon Nancy's request, I checked the status of the suspensions.

I found that the power strip of the 1Y4 rack was turned off.
Since it has a over current breaker, I don't know whether it happened by someone or over current.

Anyway, I restarted the sus computers, and now the suspensions are damping as usual.
The MC has been aligned, the auto locker is also working.


Incidentally, I found that the WFS servos are not working. Actually since the last night
It repeated losing lock and unlock.

Probably some values of the matrix or the gain is wrong.
I left the WFS as it is because Nancy will put new values this afternoon.
I will ask her to confirm that the old values work at the end of her work.

  3368   Thu Aug 5 16:18:37 2010 AlastairUpdateGeneralclocks still not locked fully - hut removed

The rubidium clocks are still not quite locked together, though it is clear that the beat frequency has dropped a lot since yesterday.

I checked on the clocks and the 1pps sync light is on.  The clocks are really hot again though despite the gap left at the bottom of the igloo.  The side of the clocks were hot enough to not be touchable.

I made the executive decision that I would remove the hut just now.  We can let the clocks lock together and then put the hut back on just before measuring.  This way the hut will isolate from temperature fluctuations during the measurement but it won't be running at the hotter equilibrium temperature.  I hope that the temperature won't change too much during the measurement if we put the hut back on.

RA: Attachment deleted because it was in Postscript format. Also not allowed here are the Stone Tablet and Cave Painting formats.

  3369   Thu Aug 5 17:59:23 2010 KojiUpdatePSLCable removal from the control room

[Alberto, Kiwamu, and Koji]

We removed the BNC cables from the control room.
The work was as hard as the one I had when I swept a 300m tunnel with a vacuum...

If we could remove the video cables, that would be a real epoch.

We found that the cabling behind the AP table is still quite ugly....grurrrh

Attachment 1: IMG_2684.jpg
IMG_2684.jpg
  3370   Thu Aug 5 22:36:11 2010 KojiUpdatePSLPSL preparation work

PSL preparation work

Aug 5th 10am-4pm?: (Kiwamu, Alberto, Koji)

  • Removing the unused cables around the PSL table and the control room

Aug 6th 10am-4pm?: (Kiwamu (ex. noon-2pm), Alberto, Koji, Jenne ('till noon) )

  • Labeling the cables to be disconnected / making the records ==> All
  • Removals
    • the big nuts at the side of the PSL table ==> Steve
    • the cable ties on the PSL frame ==> Easy
    • Innolight 2W ==> Kiwamu
    • the green pickoff optics at the edge, if necessary ==> Kiwamu talking with Steve
    • Optics on the shelf ==> Jenne / Koji
    • Oscilloscopes on the shelf ==> Jenne / Koji
    • CCD camera connections (optional, as far as not critical for the operation)
  • Put poles on the table (for the plastic sheet) ==> Alberto / Koji

Aug 9th  9am-5pm: (Steve, Jenne, Alberto, Koji)

  • Disconnecting the cables ==> All
  • Shutting down the PSL ==> Steve/Koji
    • Draining the cooling water  ==> Steve
  • Removals
    • The accelerometers ==> Jenne
    • the PSL chamber ==> Steve
    • Periscopes ==> Alberto
  • Sealing of the table with the plastic sheets

 

  • The chiller is planned to go to MIT

 

  3371   Fri Aug 6 08:09:15 2010 steveUpdatePSLPSL preparation work

Quote:

PSL preparation work

Aug 5th 10am-4pm?: (Kiwamu, Alberto, Koji)

  • Removing the unused cables around the PSL table and the control room

Aug 6th 10am-4pm?: (Kiwamu (ex. noon-2pm), Alberto, Koji, Jenne ('till noon) )

  • Labeling the cables to be disconnected / making the records ==> All
  • Removals
    • the big nuts at the side of the PSL table ==> Steve
    • the cable ties on the PSL frame ==> Easy
    • Innolight 2W ==> Kiwamu
    • the green pickoff optics at the edge, if necessary ==> Kiwamu talking with Steve
    • Optics on the shelf ==> Jenne / Koji
    • Oscilloscopes on the shelf ==> Jenne / Koji
    • CCD camera connections (optional, as far as not critical for the operation)
  • Put poles on the table (for the plastic sheet) ==> Alberto / Koji

Aug 9th  9am-5pm: (Steve, Jenne, Alberto, Koji)

  • Disconnecting the cables ==> All
  • Shutting down the PSL ==> Steve/Koji
    • Draining the cooling water  ==> Steve
  • Removals
    • The accelerometers ==> Jenne
    • the PSL chamber ==> Steve
    • Periscopes ==> Alberto
  • Sealing of the table with the plastic sheets

 

  • The chiller is planned to go to MIT

 

Monday, August 9

 We should move the reference cavity too. Will this cavity be pumped while relocated?

Check and insure that attached and cut-free cables of PSL have enough room to tolerate the raising of the enclosure by 6"

I had second thoughts about the power line to the OMC. Koji was right, we should disconnect them from the power supplies.

The PSL enclosure doors on the north side will have to be removed some times to move exiting and entering ports.

 

  3372   Fri Aug 6 10:44:55 2010 nancy, kojiUpdateIOOMode Cleaner WFS

Quote:

Upon Nancy's request, I checked the status of the suspensions.

I found that the power strip of the 1Y4 rack was turned off.
Since it has a over current breaker, I don't know whether it happened by someone or over current.

Anyway, I restarted the sus computers, and now the suspensions are damping as usual.
The MC has been aligned, the auto locker is also working.


Incidentally, I found that the WFS servos are not working. Actually since the last night
It repeated losing lock and unlock.

Probably some values of the matrix or the gain is wrong.
I left the WFS as it is because Nancy will put new values this afternoon.
I will ask her to confirm that the old values work at the end of her work.

 Yesterday , I put in the Output Matrix, and changed the gain sliders for the 4 WFS loops.

It worked and was keeping the lock for the MC.

I then tested whether the MC1 and 3 were following any change in MC2 alignment. It was indeed workinng,

Next we stepped to putting in the gains for the MC2 oplev servo.

the signs are decided on the basis of convergence, and the magnitude is kept very low, to have a very slow control for MC2.

This complete 6 * 6 model does work, and was able to keep the transmission held.

I also tried poking each mirror in pitcg and yaw, and the cavity comes back to high resonance after some time.

This time is indeed large if the poking is made for MC2, and the transmission comes back to normal after big oscillations.

I tried to measure the Open loop TFs for all these loops yesterday, but somehow could not find a correct excitation.

I will do it today.

Plan ahead :

1.  Center the spot on MC2 and the QPD

2. Optimize the gains by looking at response to noise.

3. Measure Power Spectrum Density of each error signal.

 

  3373   Fri Aug 6 12:22:04 2010 JenneUpdateIOOMC data taking over the weekend

Nancy has the Mode Cleaner for her work for the night, and is going to leave the MC happy, locked, autolocker on, WFS enabled, the works, and write down in the elog the time that she's finished. After that, I'm taking MC/seismic data all weekend long.  During the weekend, if at all possible, please don't go into the IFO room, especially near the Mode Cleaner.  If you do need to go into the IFO room, please elog the time you went in, and the time you left so I can correlate it with my dataThis is actually important, so please stick a quick elog entry in if you even think about opening the doors to the IFO room. It is much appreciated. 

  3374   Fri Aug 6 12:33:10 2010 KojiUpdateIOOMode Cleaner WFS

 Yesterday , I put in the Output Matrix, and changed the gain sliders for the 4 WFS loops.

From how much to how much have you chnged the gain?

Next we stepped to putting in the gains for the MC2 oplev servo.

I like to put the credit to Aidan for teaching Nancy how to use FOTON.

 

This complete 6 * 6 model does work, and was able to keep the transmission held.

This should be in this size:

This complete 6 * 6 model does work,
and was able to keep the transmission held.
Y
eeeeah
!

 

  3375   Fri Aug 6 12:44:29 2010 KojiUpdateIOOMC data taking over the weekend

Question:

Do you like to keep the WFS turned on?

This may change the transfer functions between the ground motion to the angle time by time,
and thus change the TF between the GND and the MCL.

Quote:

Nancy has the Mode Cleaner for her work for the night, and is going to leave the MC happy, locked, autolocker on, WFS enabled, the works, and write down in the elog the time that she's finished. After that, I'm taking MC/seismic data all weekend long.  During the weekend, if at all possible, please don't go into the IFO room, especially near the Mode Cleaner.  If you do need to go into the IFO room, please elog the time you went in, and the time you left so I can correlate it with my dataThis is actually important, so please stick a quick elog entry in if you even think about opening the doors to the IFO room. It is much appreciated. 

 

  3376   Fri Aug 6 15:50:29 2010 GopalUpdateOptic Stacks(Much Better Looking) Displacement-Displacment Transfer Functions

I reran the FDA in COMSOL on the MC1/MC3 Stack and produced the following Displacement-Displacement Transfer Functions:

X-Translational Drive has a blue background

Y-Translational Drive has a red background

Z-Translational Drive has a green background

Obtaining the Displacement-to-Phase part of the Transfer Function still produces difficulties -- I'm still working on the COMSOL-Matlab interface to perhaps better facilitate this.

RA: I have deleted those plots because they weren't transfer functions. Transfer functions must always be the ratio of something to something. For example: if I had a nickel for every bad plot I see, I would be a millionaire. In that example, the transfer function would have the units of nickels/plots. For the stacks, it should be meters/meter.

 

Attachment 1: MC1_MC3_XTrans.png
MC1_MC3_XTrans.png
Attachment 2: MC1_MC3_YTrans.png
MC1_MC3_YTrans.png
Attachment 3: MC1_MC3_ZTrans.png
MC1_MC3_ZTrans.png
  3377   Fri Aug 6 16:20:08 2010 ranaUpdateGeneralclocks still not locked fully - phase shifted

 I tried to get the clocks to be closer to 90 deg for the relative phase by adding some cable length to one of the lines, but they are still wandering too much. We need to use the serial interface and up the gain in their 1PPS locking loops.

Attachment 1: Untitled.pdf
Untitled.pdf
  3378   Fri Aug 6 17:47:36 2010 steveSummaryGeneralcranes load tested at 1998 lbs

Quote:

Quote:

Quote:

The guy from KroneCrane (sp?) came today and started the crane inspection on the X End Crane. There were issues with our crane so he's going to resume on Monday. We turned off the MOPA fur the duration of the inspection.

  1. None of our cranes have oil in the gearbox and it seems that they never did since they have never been maintained. Sloppy installation job. The crane oiling guy is going to come in on Monday.
  2. They tried to test the X-End crane with 2500 lbs. (its a 1 ton crane). This tripped the thermal overload on the crane as intended with this test. Unfortunately, the thermal overload switch disabled the 'goes down' circuit instead of the 'goes up' circuit as it should. We double checked the wiring diagram to confirm our hypothesis. Seems the X-End crane was wired up incorrectly in the first place 16 years ago. We'll have to get this fixed.

The plan is that they will bring enough weight to test it at slightly over the rating (1 Ton + 10 %) and we'll retry the certification after the oiling on Monday.

 The south end crane has one more flaw. The wall cantilever is imbalanced: meaning it wants to rotate south ward, because its axis is off.

This effects the rope winding on the drum as it is shown on Atm2

Atm1 is showing Jay Swar of KoneCrane and the two 1250 lbs load that was used for the test. Overloading the crane at 125% is general practice at load testing.

It was good to see that the load brakes were working well at 2500 lbs. Finally we found a good service company! and thanks for Rana and Alberto

for coming in on Saturday.

 Jeff Stinson, technician of KoneCrane inspected the south end crane hoist gear box. This was the one that was really low on oil. The full condition require

~ 950cc of EPX-7 (50-70W) high viscosity gear oil. The remaining 120 cc oil was drained and the gear box cover was removed. See Atm 1

He found the gear box, load brake and gearing in good condition. The slow periodic sound of the drive was explained by the split bearings at Atm 3

The Vertex and the east end crane gear boxes needed only 60 cc oil to be added to each Atm 4 and their drives were tested.

Conclusion: all 3 gear boxes and drives are in good working condition.

Tomorrow's plan: load test at 1 ton and correct-check  3 phase wiring.

 Atm1, service report: load test were performed at max horizontal reach with 1998 lbs ( American Ton is 2000 lbs)

          Vertical drives and brakes worked well. The 5 minutes sagging test showed less than 1 mm movement .

          The wiring is correct. Earlier hypothesis regarding the wiring ignored the mechanical brake action.

Our cranes are certified now. Operator training and SOP is in the work.

Vertex Folding I -beam will get latch-lock and the south end I-beam will be leveled.

Atm2, south end

Atm3, east end

Atm4, folding crane at ITMX at 14 ft horizontal reach

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  3380   Fri Aug 6 19:46:59 2010 GopalUpdateOptic Stacks(Much Better Looking) Displacement-Displacment Transfer Functions

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I reran the FDA in COMSOL on the MC1/MC3 Stack and produced the following Displacement-Displacement Transfer Functions:

X-Translational Drive has a blue background

Y-Translational Drive has a red background

Z-Translational Drive has a green background

Obtaining the Displacement-to-Phase part of the Transfer Function still produces difficulties -- I'm still working on the COMSOL-Matlab interface to perhaps better facilitate this.

RA: I have deleted those plots because they weren't transfer functions. Transfer functions must always be the ratio of something to something. For example: if I had a nickel for every bad plot I see, I would be a millionaire. In that example, the transfer function would have the units of nickels/plots. For the stacks, it should be meters/meter.

 

My apologies for the mislabeled axes on my previous plots. They have been corrected to a ratio (in./in.), as Rana so kindly suggested in his helpful, not-at-all-condescending response.

I have chosen to stay in the English system because all of the original stack drawings are in inches as well.

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