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ID Date Author Type Categoryup Subject
  5128   Fri Aug 5 20:44:26 2011 jamieMetaphysicsTreasureFilm crew here Monday morning

Just a reminder that a film crew will be here Monday morning, filming Christian Ott for some Discovery channel show.

They are slated to be here from 8am to 12:30pm or so.  They will take a couple of shots inside the lab, and the rest of the filming should be of Christian in the control room (which they will "clean up" and fit with "sexy lighting").  I will try to be here the whole time to oversee everything.

  5129   Fri Aug 5 22:54:29 2011 kiwamuMetaphysicsTreasureCrane crew here Monday morning

Also, according to Steve, there will be some crane guys for fixing the Y end crane issue (#5124) Monday morning.

Quote from #5128

 a film crew will be here Monday morning. They are slated to be here from 8am to 12:30pm or so. 

  5139   Mon Aug 8 13:24:00 2011 steveMetaphysicsTreasure Monday morning

Quote:

Just a reminder that a film crew will be here Monday morning, filming Christian Ott for some Discovery channel show.

They are slated to be here from 8am to 12:30pm or so.  They will take a couple of shots inside the lab, and the rest of the filming should be of Christian in the control room (which they will "clean up" and fit with "sexy lighting").  I will try to be here the whole time to oversee everything.

Konecrane Fred was early this morning. He diagnosed the ETMY crane horizontal drive gear box dead and left just before the film crew showed up.

New gear box should be here by the end of this week for installation.

The lab air quality is high ~20,000 counts of particles of 0.5 micron.  Keep an eye on this before you open the chamber.

Attachment 1: P1080147.JPG
P1080147.JPG
  5257   Wed Aug 17 17:51:54 2011 JenneUpdateTreasurePrepared for drag wiping

While waiting for the IFO team to align things (there were already ~5 people working on a ~1 person job...), I got all of our supplies prepped for drag wiping in the morning. 

The syringes are still on the flow bench down the Xarm.  I put fresh alcohol from unopened spectrometer-grade bottles into our alcohol drag wiping bottles.

The ITMs already had rails for marking their position in place from the last time we drag wiped.  I placed marker-rails for both ETMs.

  5262   Thu Aug 18 10:59:04 2011 steveUpdateTreasurePrepared for drag wiping

Quote:

While waiting for the IFO team to align things (there were already ~5 people working on a ~1 person job...), I got all of our supplies prepped for drag wiping in the morning. 

The syringes are still on the flow bench down the Xarm.  I put fresh alcohol from unopened spectrometer-grade bottles into our alcohol drag wiping bottles.

The ITMs already had rails for marking their position in place from the last time we drag wiped.  I placed marker-rails for both ETMs.

 We should use the deionizer before drag wiping with isopropanol.

  5281   Tue Aug 23 01:05:40 2011 JenneUpdateTreasureAll Hands on Deck, 9am!

We will begin drag wiping and putting on doors at 9am tomorrow (Tuesday). 

We need to get started on time so that we can finish at least the 4 test masses before lunch (if possible). 

We will have a ~2 hour break for LIGOX + Valera's talk.

 

I propose the following teams:

(Team 1: 2 people, one clean, one dirty) Open light doors, clamp EQ stops, move optic close to door.  ETMX, ITMX, ITMY, ETMY

(Team 2: K&J) Drag wipe optic, and put back against rails. Follow Team 1 around.

(Team 3 = Team 1, redux: 2 people, one clean, one dirty) Put earthquake stops at correct 2mm distance. Follow Team 2 around.

(Team 4: 3 people, Steve + 2) Close doors.  Follow Team 3 around.

Later, we'll do BS door and Access Connector.  BS, SRM, PRM already have the EQ stops at proper distances.

 

  5918   Wed Nov 16 21:01:08 2011 JenneUpdateTreasureeom box

I made a super sweet new foam box for our EOM.  It's awesome, and should be reasonably easy to duplicate.  Check out the PHOTOS!

Notes:

* I didn't think I was going to cover the inside of the box at first, since the foam is non-fuzz-generating, but Koji suggested it would be a good idea anyway.  The foam was cut perfectly to the EOM, so adding the tape inside makes it a tight fit.  Especially height-wise...leave a little space next time.

* To cover the insides of the optical path holes, do it in 2 parts.  One half-cylinder, and then another.  Way easier than trying to do the whole thing at once.  Also, pre-cut the tabs on both sides of the foil before inserting.  Then you just have to grab the tabs with tweezers and flatten them, and they hold the aluminum tape in place. 

* Having 1" wide, 2" wide and 3" wide aluminum tape was handy.  3" to make the top, 2" for the sides, and 1" for the inside of the holes. 

  8127   Thu Feb 21 13:34:35 2013 JenneUpdateTreasureIR card removed

Quote:

The sensor card on the bottom of the chamber was not salvaged yet.

 Yuta retrieved the IR card that had fallen to the bottom of the IOO chamber, just before we put on the access connector yesterday.  The clean "pickle picker" long grabber tool worked wonders.

  8544   Tue May 7 19:58:28 2013 ranaFrogsTreasurerabbitt whole

controls@rosalba:/opt/rtcds/caltech/c1/medm/c1ioo/master/master/master 0$ ls
C1IOO_LKIN_OUT_MTRX.adl   C1IOO_MC_ASS_LOCKIN5.adl     C1IOO_WFS1_I.adl             C1IOO_WFS_LKIN.adl
C1IOO_LOCKMC.adl          C1IOO_MC_ASS_LOCKIN6.adl     C1IOO_WFS1_Q.adl             C1IOO_WFS_MASTER.adl
C1IOO_LOCKMC_BAK.adl      C1IOO_MC_ASS_PIT_LOCKIN.adl  C1IOO_WFS1_SETTINGS.adl      C1IOO_WFS_MASTER.adl~
C1IOO_MC_ALIGN.adl        C1IOO_MC_ASS_YAW_LOCKIN.adl  C1IOO_WFS1_SETTINGS.adl.old  C1IOO_WFS_MASTER_BAK.adl
C1IOO_MC_ALIGN.adl~       C1IOO_MC_LOCKINS.adl         C1IOO_WFS2_I.adl             C1IOO_WFS_OUTMATRIX.adl
C1IOO_MC_ALIGN_BAK.adl    C1IOO_MC_SERVO.adl           C1IOO_WFS2_Q.adl             C1IOO_WFS_QPD.adl
C1IOO_MC_ASS.adl          C1IOO_MC_TRANS_QPD.adl       C1IOO_WFS2_SETTINGS.adl      C1IOO_WFS_QPD.adl.old
C1IOO_MC_ASS_LOCKIN1.adl  C1IOO_Mech_Shutters.adl      C1IOO_WFS2_SETTINGS.adl.old  fmX
C1IOO_MC_ASS_LOCKIN2.adl  C1IOO_MODECLEANER.adl        C1IOO_WFS_HEADS.adl          junk
C1IOO_MC_ASS_LOCKIN3.adl  C1IOO_QPDS.adl               C1IOO_WFS_HEADS.adl.old      master
C1IOO_MC_ASS_LOCKIN4.adl  C1IOO_QPDS_BAK.adl           C1IOO_WFS_INMATRIX.adl       svn-commit.tmp~
controls@rosalba:/opt/rtcds/caltech/c1/medm/c1ioo/master/master/master 0$ cd master
controls@rosalba:/opt/rtcds/caltech/c1/medm/c1ioo/master/master/master/master 0$ cd master
controls@rosalba:/opt/rtcds/caltech/c1/medm/c1ioo/master/master/master/master/master 0$ cd master
controls@rosalba:/opt/rtcds/caltech/c1/medm/c1ioo/master/master/master/master/master/master 0$ cd master
controls@rosalba:/opt/rtcds/caltech/c1/medm/c1ioo/master/master/master/master/master/master/master 0$ cd master
controls@rosalba:/opt/rtcds/caltech/c1/medm/c1ioo/master/master/master/master/master/master/master/master 0$ cd master
controls@rosalba:/opt/rtcds/caltech/c1/medm/c1ioo/master/master/master/master/master/master/master/master/master 0$ cd master
controls@rosalba:/opt/rtcds/caltech/c1/medm/c1ioo/master/master/master/master/master/master/master/master/master/master 0$ cd master
controls@rosalba:/opt/rtcds/caltech/c1/medm/c1ioo/master/master/master/master/master/master/master/master/master/master/master 0$ cd master
controls@rosalba:/opt/rtcds/caltech/c1/medm/c1ioo/master/master/master/master/master/master/master/master/master/master/master/master 0$ cd master
controls@rosalba:/opt/rtcds/caltech/c1/medm/c1ioo/master/master/master/master/master/master/master/master/master/master/master/master/master 0$ cd master
controls@rosalba:/opt/rtcds/caltech/c1/medm/c1ioo/master/master/master/master/master/master/master/master/master/master/master/master/master/master 0$ cd master
controls@rosalba:/opt/rtcds/caltech/c1/medm/c1ioo/master/master/master/master/master/master/master/master/master/master/master/master/master/master/master 0$ cd master
controls@rosalba:/opt/rtcds/caltech/c1/medm/c1ioo/master/master/master/master/master/master/master/master/master/master/master/master/master/master/master/master 0$ cd master
controls@rosalba:/opt/rtcds/caltech/c1/medm/c1ioo/master/master/master/master/master/master/master/master/master/master/master/master/master/master/master/master/master 0$ cd master
controls@rosalba:/opt/rtcds/caltech/c1/medm/c1ioo/master/master/master/master/master/master/master/master/master/master/master/master/master/master/master/master/master/master 0$ cd master
controls@rosalba:/opt/rtcds/caltech/c1/medm/c1ioo/master/master/master/master/master/master/master/master/master/master/master/master/master/master/master/master/master/master/master 0$ cd master
controls@rosalba:/opt/rtcds/caltech/c1/medm/c1ioo/master/master/master/master/master/master/master/master/master/master/master/master/master/master/master/master/master/master/master/master 0$ cd master
controls@rosalba:/opt/rtcds/userapps/trunk/isc/c1/medm/c1ioo 0$ cd master
controls@rosalba:/opt/rtcds/userapps/trunk/isc/c1/medm/c1ioo/master 0$ cd master
controls@rosalba:/opt/rtcds/userapps/trunk/isc/c1/medm/c1ioo/master/master 0$ cd master
controls@rosalba:/opt/rtcds/userapps/trunk/isc/c1/medm/c1ioo/master/master/master 0$ cd master
controls@rosalba:/opt/rtcds/userapps/trunk/isc/c1/medm/c1ioo/master/master/master/master 0$ helppp
helppp: command not found
controls@rosalba:/opt/rtcds/userapps/trunk/isc/c1/medm/c1ioo/master/master/master/master 127$ help me
bash: help: no help topics match `me'.  Try `help help' or `man -k me' or `info me'.

  9028   Mon Aug 19 10:16:15 2013 PicassoMetaphysicsTreasureoutsider art

 ranasglory.png

  9159   Wed Sep 25 17:07:08 2013 ranaFrogsTreasureFree Green Mango Juice in fridge

aam_pana_recipe.jpg

its an acquired taste, but its a must since we're sending an interferometer to India

  9454   Tue Dec 10 17:27:47 2013 JenneUpdateTreasureBaby oplev LQR designed loop

I *finally* figured out how to bend Matlab to my will, and close a very simple oplev loop using LQR technology. 

This is super, super simple, but it's a step in the right direction.  There is no noise, just a simple pendulum with a resonant frequency of 0.75Hz, and a Q of 10.  The LQR tries to keep the position of the pendulum at a minimum, and does not care at all about the velocity.  You cannot (with Matlab's LQR, at least that I can find) make it care "0" about the control output, so it cares about the control output a factor of 1e-4 as much as the position.

Here are some plots:

The first plot has the open loop system (just the pendulum, no control at all), as well as the closed loop system (the pendulum under control).

NoControlVsClosedLoop_BabyOplev.png

Plot 2 is the open loop gain of the controller that the LQR designed.

OpenLoopGain_BabyOplev.png

Plots 3 and 4 are the step and impulse responses of the open loop (pendulum with no control), and closed loop (pendulum with feedback) systems.

StepResp_BabyOplev.png

ImpResp_BabyOplev.png

The conclusion from the plots (if this were an interesting system) is that it doesn't take much to damp an ideal pendulum.  The real conclusion here is that I think I now know how to use the Matlab LQR function, and can make a loop with some noise now.

  9476   Sun Dec 15 20:37:41 2013 ranaSummaryTreasureThere is a Wagonga in the container that Steve does not believe in

From Linda and Bram:

Attachment 1: WagSu.pdf
WagSu.pdf
Attachment 2: Wagonga.jpg
Wagonga.jpg
Attachment 3: MandehlingMedStrong.jpg
MandehlingMedStrong.jpg
  10482   Wed Sep 10 02:35:54 2014 JenneHowToTreasureSecret scripts, revealed!

 I hereby confess to having a secret script.  But it is secret no longer!

It's a "goLock" script, and it is now in the path from any terminal.  It kills any open medm sessions (to clean up desktops), and then opens a palette of screens that I find useful.  It also starts up the CARM and DARM ALS watch scripts, and the toggle shutter scripts.  It then leaves the terminal in .../scripts/PRFPMI/ , which is where the carm_cm_up.sh script that we've been using lives.

I also made tonight a "goHome" script, but all that one does so far is set the LSC mode to OFF.  The other thing that this could / should do is restore all optics so we don't have hysteresis problems.

Also, also, my "new" misalign / restore scripts had a bug, in that they were always switching oplevs for the PRM, no matter what optic was requested.  This sometimes caused the PRM oplev to be engaged while the optic was misaligned, so the PRM would get rung up.  This has been fixed.

  10899   Wed Jan 14 02:11:07 2015 ranaSummaryTreasure2-loop Algebra Loopology

I show here the matrix formalism to calculate analytically the loop TF relationships for the IMC w/ both FSS actuators so that it would be easier to interperet the results.

The attached PDF shows the Mathematica notebook and the associated block diagram.

In the notebook, I have written the single hop connection gains into the K matrix. P is the optical plant, C is the Common electronic gain, F is the 'fast' NPRO PZT path, and M is the phase Modulator.

G is the closed loop gain matrix. The notation is similar to matlab SS systems; the first index is the row and the second index is the column. If you want to find the TF from node 2 to node 3, you would ask for G[[3,2]].

As examples, I've shown how to get the FAST gain TF that I recently made with the Koji filter box as well as the usual OLG measurement that we make from the MC servo board front panel.

Attachment 1: FSSloop.pdf
FSSloop.pdf FSSloop.pdf
Attachment 2: FSSloop.png
FSSloop.png
  10945   Tue Jan 27 17:58:21 2015 JenneConfigurationTreasureWelcome, Donatella!

Welcome to your new abode, Donatella!

Attachment 1: IMG_1806.JPG
IMG_1806.JPG
  10961   Fri Jan 30 11:37:20 2015 manasaFrogsTreasureSP table madness ends

SP table has been a mess because Q and I had let our SURF leave without cleaning up.

I cleaned up the SP table, put things back where they belong and did some sorting. I will put back the optomechanics where they belong sometime later.

For now, check out the SP table next time you are looking for a Y1  or lens or BS.

 

 

 

  11040   Mon Feb 16 21:52:51 2015 ranaHowToTreasurebig Dataviewer windows

Following this entry, I have made the same change in the controls account on rossa:

In the ~/.grace/gracerc file (create one if it doesn't exist), put in a line which reads:

PAGE LAYOUT FREE

Now we can scale our dataviewer live and playback plots by stretching the window with our mouse. The attached screenshot shows how I filled up one of the vertical monitors with a DV window for arm locking.

Attachment 1: bigDV.png
bigDV.png
  11096   Wed Mar 4 00:50:36 2015 ranaBureaucracyTreasureTransitioned DARM to AS55Q, some other work

Just in case there was some confusion, the champagne on my desk is not to be opened before I get back, no matter how many signals are transitioned to RF.

  11124   Mon Mar 9 16:50:35 2015 Champagne DuckFrogsTreasureCelebrating Lock

Attachment 1: 2015-03-09_16.35.47.jpg
2015-03-09_16.35.47.jpg
  11369   Mon Jun 22 14:21:42 2015 SteveMetaphysicsTreasureJenne and Den graduated

Last supper before departing at  "Grazie" El Portal. All the best on your journey!

Attachment 1: ls.jpg
ls.jpg
  11986   Thu Feb 11 14:28:50 2016 SteveUpdateTreasure091415 declared

   Beautifully Done

   Chirp

  what is next?

Atm 3, Ron Drever could not celebrate with us because of health issues.

 

Attachment 1: 091415declared.jpg
091415declared.jpg
Attachment 2: You_were_right!.jpg
You_were_right!.jpg
Attachment 3: P1080312.JPG
P1080312.JPG
  12007   Wed Feb 24 09:06:25 2016 SteveUpdateTreasurethe way it happened

 Celebration

Quote:

   Beautifully Done

   Chirp

  what is next?

Atm 3, Ron Drever could not celebrate with us because of health issues.

 

 

Attachment 1: IMG_0120.JPG
IMG_0120.JPG
  12562   Fri Oct 14 15:47:00 2016 ranaUpdateTreasurefilters + clip

I say just fix the clipping. Don't worry about the PRM OSEM filters. We can do that next time when we put in the ITM baffles. No need for them on this round.

  12694   Fri Jan 6 17:00:26 2017 ranaFrogsTreasureVideo of Lab Tour

In this video: https://youtu.be/iphcyNWFD10, the comments focus on the orange crocs, my wrinkled shirt, and the first aid kit.

  12917   Wed Mar 29 16:38:00 2017 SteveOmnistructureTreasuresus fiber illluminated
Attachment 1: fiber.jpg
fiber.jpg
  12919   Thu Mar 30 10:41:56 2017 ranaOmnistructureTreasuresus fiber illluminated

Very, very cool!  yes

  12922   Fri Mar 31 16:10:33 2017 SteveUpdateTreasureLes Guthman

Les Guthman interviews  gradstudent Graig.

Main laser emergency shut off was acuated by accident during this fiming. The laser is turned on.

  13140   Tue Jul 25 00:03:01 2017 ranaOmnistructureTreasurecoffee pot lid

I have recommissioned the Zojirushi coffee pot lid. You may, once again, align the dots in order to make the carafe pourable.

Details:

The Zojirushi lid is a two part mechanism:

  1. The top part of the lid must be removed for cleaning.
  2. When replacing the lid the two components must be aligned to < 3 mrad precision so that the "teeth" are able to land in the groove.
  3. There is a 4-fold degeneracy in this process. To break the degeneracy, align the dot on top with the spout gap (visible from the bottom view).
  4. After proper alignment and mating, the two parts should snap together and the relative alignment wiggle available should be < 2 mrad.
  5. After screwing the two-piece lid onto the carafe, ensure that the 2 dots are separated by < 170 deg in the closed position.
  14124   Thu Aug 2 16:30:08 2018 SteveUpdateTreasuretime capsule location

I 've just found this time capsule note from Nov. 26, 2000 by Kip Thorne:  LIGO will discover gravitational waves by Dec.31, 2007

Quote:

   Beautifully Done

   Chirp

  what is next?

Atm 3, Ron Drever could not celebrate with us because of health issues.

 

 

Attachment 1: time_capsule.JPG
time_capsule.JPG
  14265   Fri Nov 2 09:47:57 2018 SteveMetaphysicsTreasureZojirushi is dead

     It took at least ten years to rust away. crying

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Attachment 2: zoji.JPG
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  14271   Mon Nov 5 15:55:39 2018 SteveMetaphysicsTreasureZojirushi is dead

We have no coffee machine.

We are dreaming about it

We still do not have it.

Attachment 1: zoji.JPG
zoji.JPG
  14272   Tue Nov 6 09:45:32 2018 aaronMetaphysicsTreasureZojirushi is dead

New all organic machine.

  16441   Sun Oct 31 14:21:31 2021 ranaHowToTreasureIFOCad

IFOcad model/video of the AEI 10m interferometer:

https://10m.aei.mpg.de/design-and-sensitivity/

  16727   Tue Mar 15 13:49:44 2022 Ian MacMillanBureaucracyTreasureNew Screwdriver Bits

I have received the new screwdriver bits that will work with the two electric screwdrivers we have. I have distributed them in the 40m. Some are in the electronics stations and some are in the toolbox in the lab. The new electric screwdriver (which looks like a drill but takes typical screwdriver bits) is in the room with the workshop. It is in the blue Makita box. For some reason, lots of the old bits were rounded because of incorrect use. I have thrown the unuseable ones out.

I also requested some screw extractors in case we need them. the one we have now is really big and may not work on smaller screws.

  17139   Wed Sep 14 15:40:51 2022 JCUpdateTreasurePlastic Containers

There are brand new empty plastic containers located inside the shed that is outside in the cage. These can be used for organizing new equipment for CDS, or cleanup after Wednesday meetings

Attachment 1: B0DD2BEC-E57E-4AA2-8672-2ABB41F44F84.jpeg
B0DD2BEC-E57E-4AA2-8672-2ABB41F44F84.jpeg
  14153   Fri Aug 10 11:29:39 2018 aaronConfigurationUpgradeParts list for BHD

I've started putting together a list of things we'll need to buy to do BHD readout. I'm still messing around with more detailed optics layouts, but wanted to get a list started here so people can let me know if I'm missing any big, obvious categories of goods.

My current plan makes minimal changes to the signal path going to the OMC, and tries to just get the LO beam into the OMC with minimal optics. I'm not thinking of any of the optics as suspended, and it requires several reflections of the LO beam, so probably this is not an excellent configuration, but it's a start for getting the parts list:

  1. My current thought is to use the MC reflection, the beam that heads from MC1 to MCR1, as the LO beam
    1. From MCR1, send the LO to a BS that directs it into an MMT, oriented along x (and lets us keep the MC refl PO)
    2. After the two MMT optics, the beam will be traveling along -x, and can be directed to a mirror that sends it towards -y to two steering mirrors that send it along -x then +x near the top of the table (perpendicular to the signal MMT.
    3. Then, send it to a PBS, which replaces the mirror directly after the signal MMT. This is where it combines 
  2. Beam is then sent to the steering mirrors to bring it into the OMC
  3. In parallel, the signal beam is going through the same path it has now, including the pickoff beam, with the one change that we need a HWP somewhere before the PBS, and the PBS replaces the mirror directly after the MMT (and needs to move a bit closer to have the beam properly directed)

I started making a layout of this scheme, but it's probably not going to work so I'm going to make a quick layout of this more major modification instead:

  1. Both the MCR beam and the AS beam come in about parallel. Send each to a PO mirror.
  2. The PO mirror directs both beams into parallel MMT aligned along x
  3. From the MMT, each is directed to a pair of steering mirrors located where the OMC MMT is located now
  4. From the steering mirrors go to the PBS that combines the signal and LO
  5. Then to two more steering mirrors to get into the OMC, which may be moved towards +x
  6. From the OMC go to the BHD PBS

What we need

Optics

  • HWP for just before the LO combines with the signal
  • HWP for just before the signal combines with the LO (is this necessary?)
  • PBS to replace OM5 (combines the LO and the signal)
  • Two MMT optics
  • Two piezo-driven TT optics for steering the LO to the PBS
  • One additional non-piezo optic for between the LOMMT and the LO-TTs
  • One additional BS to get the LO into the MMT (and to let us still have the PO)
  • -1 optic—we pick up one mirror that we replace with the PBS

Optomechanics

  • 2x HWP mounts
  • 1x PBS mount
  • 2x mounts for piezo-driven TT
  • 2x MMT optic mounts—I didn’t take a close enough look at these during the vent to know what we need here
  • 2x mounts for ordinary optics
  • 9x clamps for optics mounts (maybe fewer if some are on blocks)
  • 9x posts for optics mounts

Electronics

  • Additional TT driver
  • HV supply for the new TTs
  • Are the HWP actively controlled? We might need something to drive those?
  • Do we have enough DAC/ADC channels?

Questions

These are mostly just miscellaneous

  1. What of these optics need to be suspended? If we need suspensions on all of the LO optics, including the MMT, I’m not sure we’re going to be able to fit all of this on the table as I envision it…..
  2. What if anything can we put out of vacuum (HWP for example)?
  3. Do we actually need two MMT?
  14154   Fri Aug 10 16:43:50 2018 gautamConfigurationUpgradeParts list for BHD

Can we use the leakage beam from MMT2 on the OMC table as the LO beam? I can't find the spec for this optic, but the leakage beam was clearly visible on an IR card even with the IMC locked with 100 mW input power so presumably there's enough light there, and this is a cavity transmission beam which presumably has some HOM content filtered out.

Quote:

My current thought is to use the MC reflection, the beam that heads from MC1 to MCR1, as the LO beam

  14155   Sun Aug 12 10:59:34 2018 aaronConfigurationUpgradeParts list for BHD

That seems fine, I wasn't thinking of that beam. in that case could we just have a PBS directly behind MMT2 and send both beams to the same OMMT?

Alternatively we can move OM5 and the beam path OMPO-OMMTSM towards -y, then put the LO-OMMT parallel to the existing OMMT but displaced in +x... we'd have to move the existing OMC and BHD towards +x as well. 

Quote:

Can we use the leakage beam from MMT2 on the OMC table as the LO beam? I can't find the spec for this optic, but the leakage beam was clearly visible on an IR card even with the IMC locked with 100 mW input power so presumably there's enough light there, and this is a cavity transmission beam which presumably has some HOM content filtered out.

  14158   Mon Aug 13 17:20:07 2018 aaronConfigurationUpgradeParts list for BHD

I've attached the diagram of what I mean.

There are a couple caveats and changes that would have to be made that are not included in this diagram, because they would be made on different tables.

  1. I moved MMT2, which means the other MMT optics would have to be adjusted to accomodate this. I checked out the configuration on the BS table and this seems doable with a small rotation of MMT1 and maybe PJ2.
  2. I don't know the best way to get the OMC REFL beam out... thoughts?
  3. This diagram is kind of crappy after my edits, someone should tell me how to avoid collapsing all layers when I open these layout diagrams in inkscape, because I ended up editing the layout in Acrobat instead, where the lack of object grouping caused a bunch of the optics to lose one or two lines along the way.
  4. I didn't include all beam paths explicitly but can if this looks like a good configuration.
  5. The optic that picks off the transmission through MMT2 will need to move a bit, but there was a clamp in the way; this should be a minor change.
  6. The optic just before the OMC needs to be moved up a bit.
  7. The optic after the signal OMMT should be changed to a PBS and translated a bit; this is where the LO and signal beams will combine

Gautam also had some questions about the BHD/OMC timeline and plan. I feel somewhat on shaky ground with the answers, but figured I'd post them so I can be corrected once and for all.

  1. Is the plan really to use the current OMC setup to make a homodyne measurement? 
    1. I'm not sure where on the timeline the new OMC and BHD switchover are relative to each other. I have been imagining doing the swap to BHD before having a new OMC.
  2. I thought the current OMC resurrection plan was to do DC readout and not homodyne?
    1. I think the OMC resurrection plan is leading to DC readout, but when we switch over to BHD we'll be able to operate at the dark fringe. Is that right?
  3. Is it really possible to use our single OMC to clean both the LO and dark port beams? Isn't this the whole raging debate for A+?
    1. My understanding is yes, with the LO and DP in orthogonal polarizations. It's not clear to me why we expect to be able to do this while there is a debate for A+, perhaps our requirements are weaker. It is something I should calculate, I'll talk to Koji.
  4. A layout diagram would be really useful.
    1. Attached now.
  5. Where in the priority list does this come in?
    1. I am a leaf in the wind. I think this comes well after we have the OMC resurrected, we just want to get a sense for what parts we need so we can order them before the fiscal year closes.
Quote:

That seems fine, I wasn't thinking of that beam. in that case could we just have a PBS directly behind MMT2 and send both beams to the same OMMT?

Alternatively we can move OM5 and the beam path OMPO-OMMTSM towards -y, then put the LO-OMMT parallel to the existing OMMT but displaced in +x... we'd have to move the existing OMC and BHD towards +x as well. 

Quote:

Can we use the leakage beam from MMT2 on the OMC table as the LO beam? I can't find the spec for this optic, but the leakage beam was clearly visible on an IR card even with the IMC locked with 100 mW input power so presumably there's enough light there, and this is a cavity transmission beam which presumably has some HOM content filtered out.

 

Attachment 1: BHD_layout.pdf
BHD_layout.pdf
  14311   Tue Nov 20 17:38:13 2018 ranaUpdateUpgradeNew Coffee Machine

Rana, Aaron, Gautam

The old Zojirushi has died. We have received and comissioned our new Technivoorm Mocha Master today. It is good.

  14327   Sun Dec 2 16:08:44 2018 JonOmnistructureUpgradeFeedthroughs for Vacuum Acromag Chassis

Below is an inventory of the signal feedthroughs that need to be installed on the vacuum Acromag crate this week.

Type Qty Connects to # Chs Signals
DB-37 female 1 Main AC relay box 18 Valve/roughing pump control
DB-9 female 5** Satellite AC relay boxes 3-4/box Valve control
DB-25 male 1 Turbo pump 1 controller 5 Pump status readbacks
DB-9 male 30 Valve position indicators 2/valve Valve position readbacks
DB-9 male 3 Roughing pump controllers 1/pump Pump status readbacks
DB-9 male 1 Cryo pump controller 2 Pump status readbacks

**The original documentation lists five satellite boxes (one for each test mass chamber and one for the beamsplitter chamber), but Chub reports not all of them are in use. We may remove the ones not used.

  14330   Tue Dec 4 10:38:12 2018 JonOmnistructureUpgradeUpdated Feedthrough List for Vacuum Acromag Chassis

Based on new input from Chub, attached is the revised list of signal cable feedthroughs needed on the vacuum system Acromag crate. I believe this list is now complete.

Attachment 1: acromag_chassis_feedthroughs.pdf
acromag_chassis_feedthroughs.pdf
  14348   Wed Dec 12 18:27:07 2018 JonOmnistructureUpgradeAnalog signals, A/D Acromag added to vacuum system

There turned out to be a few analog signals for the vacuum system after all. The TP2/3 foreline pressure gauges were never part of the digital system, but we wanted to add them, as some of the interlock conditions should be predicated on their readings. Each gauge connects to an old Granville-Phillips 375 controller which only has an analog output. Interfacing these signals with the new system required installing an Acromag XT1221 8-channel A/D unit. Taking advantage of the extra channels, I also moved the N2 delivery line pressure transducer to the XT1221, eliminating the need for its separate Omega DPiS32 controller. When the new high-pressure transducers are added to the two N2 tanks, their signals can also be connected.

The XT1221 is mounted on the DIN rail inside the chassis and I have wired a DB-9 feedthrough for each of its three input signals. It is assigned the IP 192.168.114.27 on the vacuum subnet. Testing the channels in situ revealed a subtley in calibrating them to physical units. It was first encountered by Johannes in a series of older posts, but I repeat it here in one place.

An analog-input EPICS channel can be calibrated from raw ADC counts to physical units (e.g., sensor voltage) in two ways:

  1. Via LINR="LINEAR" by setting the engineering-units fields EGUF="[V_max_adc]", EGUL="[V_min_adc]"
  2. Via LINR="NO CONVERSION" by manually setting the gain ASLO="[V/count]" and offset AOFF="[V_offset]"

From the documentation, under the engineering-units method EPICS internally computes:

where EGUF="eng units full scale", EGUL="eng units low", and "full scale A/D counts" is the full range of ADC counts. EPICS automatically infers the range of ADC counts based on the data type returned by the ADC. For a 16-bit ADC like the XT1221, this number is 2^16 = 65,536.

The problem is that, for unknown reasons, the XT1221 rescales its values post-digitization to lie within the range +/-30,000 counts. This corresponds to an actual "full scale A/D counts" = 60,001. If a multiplicative correction factor of 65,536/60,000 is absorbed into the values of EGUF and EGUL, then the first term in the above summation can be corrected. However, the second term (the offset) has no dependence on "full scale A/D counts" and should NOT absorb a correction factor. Thus adjusting the EGUF and EGUL values from, e.g., 10V to 10.92V is only correct when EGUL=0V. Otherwise there is a bias introduced from the offset term also being rescaled.

The generally correct way to handle this correction is to use the manual "NO CONVERSION" method. It constructs calibrated values by simply applying a specified gain and offset to the raw ADC counts:

calibrated val = (measured A/D counts)  x ASLO + AOFF

The gain ASLO="[(V_max_adc - V_min_adc) / 60,001]" and the offset AOFF="0". I have tested this on the three vacuum channels and confirmed it works. Note that if the XT1221 input voltage range is restricted from its widest +/-10V setting, the number of counts is not necessarily 60,001. Page 42 of the manual gives the correct counts for each voltage setting.

  14375   Thu Dec 20 21:29:41 2018 JonOmnistructureUpgradeVacuum Controls Switchover Completed

[Jon, Chub, Koji, Gautam]

Summary

Today we carried out the first pumpdown with the new vacuum controls system in place. It performed well. The only problem encountered was with software interlocks spuriously closing valves as the Pirani gauges crossed 1E-4 torr. At that point their readback changes from a number to "L OE-04, " which the system interpreted as a gauge failure instead of "<1E-4." This posed no danger and was fixed on the spot. The main volume was pumped to ~10 torr using roughing pumps 1 and 3. We were limited only by time, as we didn't get started pumping the main volume until after 1pm. The three turbo pumps were also run and tested in parallel, but were isolated to the pumpspool volume. At the end of the day, we closed every pneumatic valve and shut down all five pumps. The main volume is sealed off at ~10 torr, and the pumpspool volume is at ~1e-6 torr. We are leaving the system parked in this state for the holidays. 

Main Volume Pumpdown Procedure

In pumping down the main volume, we carried out the following procedure.

  1. Initially: All valves closed (including manual valves RV1 and VV1); all pumps OFF.
  2. Manually connected roughing pump line to pumpspool via KF joint.
  3. Turned ON RP1 and RP2.
  4. Waited until roughing pump line pressure (PRP) < 0.5 torr.
  5. Opened V3.
  6. Waited until roughing pump line pressure (PRP) < 0.5 torr.
  7. Manually opened RV1 throttling valve to main volume until pumpdown rate reached ~3 torr/min (~3 hours on roughing pumps).
  8. Waited until main volume pressure (P1a/P1b) < 0.5 torr.

We didn't quite reach the end of step 8 by the time we had to stop. The next step would be to valve out the roughing pumps and to valve in the turbo pumps.

Hardware & Channel Assignments

All of the new hardware is now permanently installed in the vacuum rack. This includes the SuperMicro rack server (c1vac), the IOLAN serial device server, a vacuum subnet switch, and the Acromag chassis. Every valve/pump signal cable that formerly connected to the VME bus through terminal blocks has been refitted with a D-sub connector and screwed directly onto feedthroughs on the Acromag chassis.

The attached pdf contains the master list of assigned Acromag channels and their wiring.

Attachment 1: 40m_vacuum_acromag_channels.pdf
40m_vacuum_acromag_channels.pdf 40m_vacuum_acromag_channels.pdf 40m_vacuum_acromag_channels.pdf
  14384   Fri Jan 4 11:06:16 2019 JonOmnistructureUpgradeVac System Punchlist

The base Acromag vacuum system is running and performing nicely. Here is a list of remaining questions and to-do items we still need to address.

Safety Issues

  • Interlock for HV supplies. The vac system hosts a binary EPICS channel that is the interlock signal for the in-vacuum HV supplies. The channel value is OFF when the main volume pressure is in the arcing range, 3 mtorr - 500 torr, and ON otherwise. Is there something outside the vacuum system monitoring this channel and toggling the HV supplies?
  • Exposed 30-amp supply terminals. The 30-amp output terminals on the back of the Sorensen in the vac rack are exposed. We need a cover for those.
  • Interlock for AC power loss. The current vac system is protected only from transient power glitches, not an extended loss. The digital system should sense an outage and put the IFO into a safe state (pumps spun down and critical valves closed) before the UPS battery is fully drained. However, it presently has no way of sensing when power has been lost---the system just continues running normally on UPS power until the battery dies, at which point there is a sudden, uncontrolled shutdown. Is it possible for the digital system to communicate directly with the UPS to poll its activation state?

Infrastructure Improvements

  • Install the new N2 tank regulator and high-pressure transducers (we have the parts; on desk across from electronics bench). Run the transducer signal wires to the Acromag chassis in the vacuum rack.
  • Replace the kludged connectors to the Hornet and SuperBee serial outputs with permanent ones (we need to order the parts).
  • Wire the position indicator readback on the manual TP1 valve to the Acromag chassis.
  • Add cable tension relief to the back of the vac rack.
  • Add the TP1 analog readback signals (rotation speed and current) to the digital system.  Digital temperature, current, voltage, and rotation speed signals have already been added for TP2 and TP3.
  • Set up a local vacuum controls terminal on the desk by the vac rack.
  • Remove gauges from the EPICS database/MEDM screens that are no longer installed or functional. Potential candidates for removal: PAN, PTP1, IG1, CC2, CC3, CC4.
  • Although it appeared on the MEDM screen, the RGA was never interfaced to the old vac system. Should it be connected to c1vac now?
  14390   Tue Jan 8 19:13:39 2019 JonUpdateUpgradeReady for pumpdown tomorrow

Everything is set for a second pumpdown tomorrow. We'll plan to start pumping after the 1pm meeting. Since the main volume is already at 12 torr, the roughing phase won't take nearly as long this time.

I've added new channels for the TP1 analog readings (current and speed) and for the two N2 tank pressure readings. Chub finished installing the new regulator and has run the transducer signal cable to the vacuum rack. In the morning he will terminate the cable and make the final connection to the Acromag.

Gautam and I updated the framebuilder config file, adding the newly-added channels to the list of those to be logged. We also set up a git repo containing all of the Python interlock/interfacing code: https://git.ligo.org/40m/vacpython. The idea is to use the issue tracker to systematically document any changes to the interlock code.

  14493   Thu Mar 21 18:36:59 2019 JonOmnistructureUpgradeVacuum Controls Switchover Completed

Updated vac channel list is attached. There are several new ADC channels.

Quote:

Hardware & Channel Assignments

All of the new hardware is now permanently installed in the vacuum rack. This includes the SuperMicro rack server (c1vac), the IOLAN serial device server, a vacuum subnet switch, and the Acromag chassis. Every valve/pump signal cable that formerly connected to the VME bus through terminal blocks has been refitted with a D-sub connector and screwed directly onto feedthroughs on the Acromag chassis.

The attached pdf contains the master list of assigned Acromag channels and their wiring.

Attachment 1: 40m_Vacuum_Acromag_Channels_20190321.pdf
40m_Vacuum_Acromag_Channels_20190321.pdf 40m_Vacuum_Acromag_Channels_20190321.pdf 40m_Vacuum_Acromag_Channels_20190321.pdf
  14495   Mon Mar 25 10:21:05 2019 JonUpdateUpgradec1susaux upgrade plan

Now that the Acromag upgrade of c1vac is complete, the next system to be upgraded will be c1susaux. We chose c1susaux because it is one of the highest-priority systems awaiting upgrade, and because Johannes has already partially assembled its Acromag replacement (see photos below). I've assessed the partially-assembled Acromag chassis and the mostly-set-up host computer and propose we do the following to complete the system.

Documentation

As I go, I'm writing step-by-step documentation here so that others can follow this procedure for future systems. The goal is to create a standard procedure that can be followed for all the remaining upgrades.

Acromag Chassis Status

The bulk of the remaining work is the wiring and testing of the rackmount chassis housing the Acromag units. This system consists of 17 units: 10 ADCs, 4 DACs, and 3 digitial I/O modules. Johannes has already created a full list of channel wiring assignments. He has installed DB37-to-breakout board feedthroughs for all the signal cable connections. It looks like about 40% of the wiring from the breakout boards to Acromag terminals is already done.

The Acromag units have to be initially configured using the Windows laptop connected by USB. Last week I wasn't immediately able to check their configuration because I couldn't power on the units. Although the DC power wiring is complete, when I connected a 24V power supply to the chassis connector and flipped on the switch, the voltage dropped to ~10V irrespective of adjusting the current limit. The 24V indicator lights on the chassis front and back illuminated dimly, but the Acromag lights did not turn on. I suspect there is a short to ground somewhere, but I didn't have time to investigate further. I'll check again this week unless someone else looks at it first.

Host Computer Status

The host computer has already been mostly configured by Johannes. So far I've only set up IP forwarding rules between the martian-facing and Acromag-facing ethernet interfaces (the Acromags are on a subnet inaccessible from the outside). This is documented in the link above. I also plan to set up local installations of modbus and EPICS, as explained below. The new EPICS command file (launches the IOC) and database files (define the channels) have already been created by Johannes. I think all that remains is to set up the IOC as a persistent system service.

Host computer OS

Recommendation from Keith Thorne:

For CDS lab-wide, Jamie Rollins and Ryan Blair have been maintaining Debian 8 and 9 repos with some of these.  
They have somewhat older EPICS versions and may not include all the modules we have for SL7.
One worry is whether they will keep up Debian 9 maintained, as Debian 10 is already out.

I would likely choose Debian 9 instead of Ubuntu 18.04.02, as not sure of Ubuntu repos for EPICS libraries.

Based on this, I propose we use Debian 9 for our Acromag systems. I don't see a strong reason to switch to SL7, especially since c1vac and c1susaux are already set-up using Debian 8. Although Debian 8 is one version out of date, I think it's better to get a well-documented and tested procedure in place before we upgrade the working c1vac and c1susaux computers. When we start building the next system, let's install Debian 9 (or 10, if it's available), get it working with EPICS/modbus, then loop back to c1vac and c1susaux for the OS upgrade.

Local vs. central modbus/EPICS installation

The current convention is for all machines to share a common installation which is hosted on the /cvs/cds network drive. This seems appealing because only a single central EPICS distribution needs to be maintained. However, from experience attempting this on c1vac, I'm convinced this is a bad design for the new Acromag systems.

The problem is that any network outage, even routine maintenance or brief glitches, wreaks havoc on Acromags set up this way. When the network is interrupted, the modbus executable disappears mid-execution, crashing the process and hanging the OS (I think related to the deadlocked NFS mount), so that the only way to recover is to manually power-cycle. Still worse, this can happen silently (channel values freeze), meaning that, e.g., watchdog protections might fail.

To avoid this, I'm planning to install a local EPICS distribution from source on c1susaux, just as I did for c1vac. This only takes a few minutes to do, and I will include the steps in the documented procedure. Building from source also better protects against OS-dependent buginess.

Main TODO items

  • Debug issue with Acromag DC power wiring
  • Complete wiring from chassis feedthroughs to Acromag terminals, following this wiring diagram
  • Check/set the configuration of each Acromag unit using the software on the Windows laptop
  • Set the analog channel calibrations in the EPICS database file
  • Test each channel ex situ. Chub and I discussed an idea to use two DB-37F breakout boards, with the wiring between the board terminals manually set. One DAC channel would be calibrated and driven to test other ADC channels. A similar approach could be used for the digital input/output channels.
Attachment 1: IMG_3136.jpg
IMG_3136.jpg
Attachment 2: IMG_3138.jpg
IMG_3138.jpg
Attachment 3: IMG_3137.jpg
IMG_3137.jpg
  14496   Tue Mar 26 04:25:13 2019 JohannesUpdateUpgradec1susaux upgrade plan
Quote:

Main TODO items

  • Debug issue with Acromag DC power wiring
  • Complete wiring from chassis feedthroughs to Acromag terminals, following this wiring diagram
  • Check/set the configuration of each Acromag unit using the software on the Windows laptop
  • Set the analog channel calibrations in the EPICS database file
  • Test each channel ex situ. Chub and I discussed an idea to use two DB-37F breakout boards, with the wiring between the board terminals manually set. One DAC channel would be calibrated and driven to test other ADC channels. A similar approach could be used for the digital input/output channels.

Just a few remarks, since I heard from Gautam that c1susaux is next in line for upgrade.

All units have already been configured with IP addresses and settings following the scheme explained on the slow controls wiki page. I did this while powering the units in the chassis, so I'm not sure where the short is coming from. Is the power supply maybe not sourcing enough current? Powering all units at the same time takes significant current, something like >1.5 Amps if I remember correctly. These are the IPs I assigned before I left:

Acromag Unit IP Address
C1SUSAUX_ADC00 192.168.115.20
C1SUSAUX_ADC01 192.168.115.21
C1SUSAUX_ADC02 192.168.115.22
C1SUSAUX_ADC03 192.168.115.23
C1SUSAUX_ADC04 192.168.115.24
C1SUSAUX_ADC05 192.168.115.25
C1SUSAUX_ADC06 192.168.115.26
C1SUSAUX_ADC07 192.168.115.27
C1SUSAUX_ADC08 192.168.115.28
C1SUSAUX_ADC09 192.168.115.29
C1SUSAUX_DAC00 192.168.115.40
C1SUSAUX_DAC01 192.168.115.41
C1SUSAUX_DAC02 192.168.115.42
C1SUSAUX_DAC03 192.168.115.43
C1SUSAUX_BIO00 192.168.115.60
C1SUSAUX_BIO01 192.168.115.61
C1SUSAUX_BIO02 192.168.115.62

I used black/white twisted-pair wires for A/D, red/white for D/A, and green/white for BIO channels. I found it easiest to remove the blue terminal blocks from the Acromag units for doing the majority of the wiring, but wasn't able to finish it. I had also done the analog channel calibrations using the windows untility using multimeters and one of the precision voltage sources I had brought over from the Bridge labs, but it's probably a good idea to check it and correct if necessary. I also recommend to check that the existing wiring particularly for MC1 and MC2 is correct, as I had swapped their order in the channel assignment in the past.

While looking through the database files I noticed two glaring mistakes which I fixed:

  1. The definition of C1SUSAUX_BIO2 was missing in /cvs/cds/caltech/target/c1susaux2/C1SUSAUX.cmd. I added it after the assignments for C1SUSAUX_BIO1
  2. Due to copy/paste the database files /cvs/cds/caltech/target/c1susaux2/C1_SUS-AUX_<OPTIC>.db files were still pointing to C1AUXEX. I overwrote all instances of this in all database files with C1SUSAUX.

 

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