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ID Date Author Type Category Subject
  12300   Wed Jul 13 21:13:51 2016 KojiUpdateGeneralETMX guide rod gluing / ETMY Magnet gluing

[Eric, Koji]

  • ETMX: The Al guide rod has been glued on the mirror.
  • ETMY: The UR, LR, and SD magnets have been glued on the mirror.
  • For both, we are waiting for the glue getting cured.

Handing over message to the next step

  • ETMX: The arm of the fixture has probably been glued together with the guide rod. It has to be taken care when the fixture is removed.
    (See
    ETMX gluing section and Attachment 13)

ETMX: guide rod gluing (done) -> fixture unmounting side -> fixture setting -> magnet gluing -> suspend -> pitch balance -> ruby gluing -> air bake
ETMY: magnet (done) -> fixture unmounting -> air bake


ETMY gluing

Mirror transport:
- A transport setup was made with a donut holder for a 3" optic, glass jar, stain less tray, and a CS Stat zipbag. (Attachment 1)

Shimming:
- The magnets have been glued witht the gluing fixture. (Attachment 2)
- We checked the dimensions of the glued magnet and found that the thicker side has to be raised by 1mm. (We used the fact that the relative distance between the wire groove and the magnet is always the same.)
- The ETMs have 2.5deg wedge and this corresponds to 3.2mm height difference between the left and right edges. This meant that the thinner side had to be raised by 4.2mm.
- We used a 0.9mm Teflon sheet for the thicker side (Attachment 3) and two 2.2mm Teflon pieces for the thinner side (Attachment 4). For stabilization of the fixture, two Teflon tubes with a diameter of ~3mm are inserted to the top and bottom side of the mirror (Attachment 5).

Magnet orientation:
- Mirror orientation in the fixture (Attachment 6).
- It was confirmed that existing UR, LR, and Right SD magnets have the polarity of N facing out, S facing out, and N facing out. And we confirmed that this is consistent with ETMX and the procedure document (E970037)
- Along with the procedure document, we arranged the magnet-dumbbells UL, LL, and Left SD magnets to have S-out, N-out, and N-out. (Attachments 7, 8, and 9)

Gluing:
- In prior to gluing, all three dumbbells surfaces were cleaned by acetone and razor blade scrubbing.
- After the epoxy curing test (see below), the three magnet-dumbbell pairs have been glued on the mirror. A single dub of EP30-2 was applied to each dumbbell surface.

- Attachments 10, 11, and 12 shows how glue is spread at each joint.

ETMX gluing

Guide rod positioning:
- The longitudinal position of the guide rod was adjusted using the micrometer microscope such that it located at the center of the mirror thickness.
- The guide rod is not long enough to have the edges sticking out from the form of the fixture arm. Therefore only arm finger of the arm held the guide rod. 
- The height was adjusted to be 1.73mm (68mil) lower than the mirror scribe line. The mirror is fixed on the fixture upside down. So this bonds the guide rod above the scribe line.

Gluing:
- Then the epoxy was applied to the guide rod. The glue was applied to two edges of the rod, but capillary action spread the glue around the rod. It seemed that the fixture and the rod were connected with the glue. Care should be taken when the fixture is going to be removed. (Attachment 13)
- The top side (in the picture) where the stand-off will come is still relatively kept clean. So it must be OK for the stand off. If there is an issue, we can shave the epoxy with a razor blade.

Glue testing

- EP30-2 tends to fail to get cured. In order to check the mixture is properly made or not, we put a test piece into air bake oven.
- The procedure says, 200F 15min bake show if the glue is in a good shape or not.

- We have the temperature sensor setup on a air bake oven, but it seemed that the indicated temperature there is overestimate.
  The heating setting of 2 was enough to show the temp of 100degC although EP30-2 didn't get cured with this setting.

- Our experience says that heater setting of "5" makes the temperature ~90degC. On July 12nd, this setting showed the temp of 90degC. Today (July 13rd) it didn't. In the both cases, the epoxy got cured nicely. So we should use this setting.

Attachment 1: P7138742.jpg
P7138742.jpg
Attachment 2: gluing_fixture.jpg
gluing_fixture.jpg
Attachment 3: shimming3.jpg
shimming3.jpg
Attachment 4: shimming1.jpg
shimming1.jpg
Attachment 5: shimming2.jpg
shimming2.jpg
Attachment 6: gluing_fixture3.jpg
gluing_fixture3.jpg
Attachment 7: P7138747.jpg
P7138747.jpg
Attachment 8: P7138748.jpg
P7138748.jpg
Attachment 9: P7138750.jpg
P7138750.jpg
Attachment 10: P7138773.jpg
P7138773.jpg
Attachment 11: P7138774.jpg
P7138774.jpg
Attachment 12: P7138775.jpg
P7138775.jpg
Attachment 13: P7138772.jpg
P7138772.jpg
  12299   Wed Jul 13 15:35:56 2016 LydiaUpdateGeneralVent Progress - ETMY repositioned and removed

[Lydia, Johannes]

Took photos to document the original OSEM orientation and wrote down the serial numbers for each position. We removed the OSEMs, moved the suspension to the accessible side of the table and took out the optic, which was brought to the clean room to have the magnets reglued. The ETMY chamber is now closed up with the OSEMs and clamps inside on the table, and should not need to be reopened until the magnets have been reattached. 

  12298   Wed Jul 13 03:16:47 2016 KojiUpdateGeneralITMX dust

Multicolor flash light:

- It seems that the usb port charging doesn't work.

- There is a battery charger on Steve's desk. I set the batteries on it.

 

White LED flash light:

- I temporarily brought a compatible charger from WB. It's charging two batteries behind the LCD display on my desk.

 

  12297   Wed Jul 13 00:38:25 2016 JohannesUpdateGeneralVent progress - ETMY attempted repositioning

[Lydia, Johannes]

We attempted to move the ETMY suspension near the access port in preparation for the cleaning process. The plan was to move in the face restraints first to the point of almost making contact, then the ones underneath so the optic is sitting on them, followed by the top one facing down, and then bringing in the stops on the faces.

While moving in the stoppers I noticed that the far lower stopper on the HR side was barely touching the face of the optic in its resting position and was basically pushing it sideways when moved forward. It was just on the edge, so I tried to compensate minimally by moving the underneath stops a little further on the near side, trying to let it 'slide' over a little so the screw would have better contact. I must have been too generous with the adjustment, because while proceeding I noticed at some point that the stick magnets on one side of the optic were not attached anymore but laying inside the OSEMs. The side magnet was also missing, it is now sitting on the suspension jig base plate. The dumbbells all seem intact, but we'll test them before we reglue the magnets to the optic. This is extremely unfortunate, but hopefully won't take too long to fix. At the very least, as Koji put it, the cleaning will be easier with the optic out of the suspension. Still, what a bummer.

  12296   Wed Jul 13 00:01:38 2016 JohannesUpdateGeneralITMX dust

We ran out of illuminator juice, and short-term charging couldn't restore enough battery life to continue the work. We should be able to get some better pictures tomorrow.

Quote:

Looked at ITMX. Johannes and I both saw a fairly large speck of dust near the center of the HR side. We tried to take some photos but couldn't get any with good focus

 

  12295   Tue Jul 12 23:51:16 2016 JohannesUpdateGeneralVent progress - ETMY inspection

On Monday I inspected ETMY, and found nothing really remarkable. There was only little dust on the HR side, and nothing visible in the center. The AR side has some visible dust, nothing too crazy, but some of it near the center.

  12294   Tue Jul 12 20:16:15 2016 LydiaUpdateGeneralITMX dust

Looked at ITMX. Johannes and I both saw a fairly large speck of dust near the center of the HR side. We tried to take some photos but couldn't get any with good focus. 

  12293   Tue Jul 12 18:13:19 2016 KojiUpdateVACN2 bottle replaced

Gautam, Koji

We replaced the right N2 bottle as it was empty.

  12292   Tue Jul 12 16:08:00 2016 ericqUpdateGeneralETMX ruby guided gluing

[ericq, Koji]

We have positioned and applied epoxy to one ruby standoff on ETMX, for overnight curing according to the SOS standoff gluing procedure. This included:

  • Removing and reinserting the guiderod until the groove is properly oriented, as seen by microscope
  • finding the right vertical offset with the microscope + 3 axis micrometer stage
  • axial centering by equalizing the distances from the grove to each bevelled edge of the barrel with the microscope stage
  • mixing epoxy
  • Testing the mix by putting some drops on some foil, and putting that in a 200F oven for 15 minutes, and checking that it cured well
  • Applying some tiny droplets of expoxy using the tip of some copper wire, making an effort to keep epoxy away from the glue

Instead of trying to fix up a way of gluing the guiderod with the proper alignment, we chose to be more conservative and glue the standoff today, then switch the gluing fixture's arms tomorrow to glue the guide rod with the good fixture arm. 

Additionally, we chose to glue one of the more assymetric standoffs on this first side. What I mean by this is: We have 3 ruby standoffs with grooves. Two of them have the groove about 1/8th of the way along their length, and one has it about 1/4 of the way. Since the second standoff is going to be glued while suspended, after pitch balancing, we figure that we want to use the more centered groove on that side, meaning we used one of the 1/8th standoffs today.

Unfortunately, we neglected to take any pictures :/

  12291   Tue Jul 12 09:35:51 2016 JohannesUpdateGeneralSlippery substance mystery

I've noticed the spot that Rich means before, too. I think you only notice this when you're wearing the shoe covers, not sneakers or crocs. I didn't see any 'substance', it seems more like the floor finish (wax?) seems to be more slippery in that area than others.

Quote:

I found a note on Steve's desk that R. Abbott left yesterday afternoon about an unidentified slippery substance being present on the floor by cabinet S12, along the X arm. (Steve is away this week)

Just now, I found no trace of the substance in the vicinity of that cabinent (which is one of the cabinets for clean objects). Maybe the janitor cleaned it already?

 

  12290   Tue Jul 12 09:18:12 2016 ericqUpdateGeneralSlippery substance mystery

I found a note on Steve's desk that R. Abbott left yesterday afternoon about an unidentified slippery substance being present on the floor by cabinet S12, along the X arm. (Steve is away this week)

Just now, I found no trace of the substance in the vicinity of that cabinent (which is one of the cabinets for clean objects). Maybe the janitor cleaned it already?

  12289   Mon Jul 11 15:13:22 2016 gautamUpdateGeneralVent progress: in-date First Contact procured

I have obtained 2x100cc bottles of in-date first contact from Garilynn (use before date is 09/14/2016) for cleaning of our test-masses. They are presently wrapped in foil in the plastic box with all the other first contact supplies.

Attachment 1: image.jpeg
image.jpeg
  12287   Sun Jul 10 20:08:44 2016 varunUpdateCDSDAFI Update: Changes in LSC and PEM models

I have added the PEM signals mentioned in the previous elog as DAF inputs through PCIE IPC, and compiled and restarted the c1pem and c1daf models. 

Attached are the pictures of the simulink diagram of the addition in the PEM and the DAF. 

Since the signals are moving from a 2kHz clock rate machine to a 16kHz clock rate machine, some imaging effects are possible, which I have to look into.

Attachment 1: pemtodaf.png
pemtodaf.png
Attachment 2: pemindaf.png
pemindaf.png
  12286   Sun Jul 10 18:20:39 2016 ranaUpdateElectronicsAntialiasing Filter Update

Comments on the schematic:

  1. Only the instrumentation amp should be made up of the ADA4004. Not the whitening parts.
  2. Please think about the front panel design and make a drawing of the front and back panels. Power connectors, indicators, switches, etc. Take a look at some of our existing 1U rack electronics to see what standard arrangements are. Add a front and back panel drawing to the elog.
  3. The whitening and anti-aliasing opamps can all be OP27 SOIC-8 for now. Later, if we need better noise performance or speed we can use faster opamps.
  4. There should be a 3rd stage of AA. Each of the exisitng stages (U5, U6) can only be second order and we want the option to have a 6th order low pass.
  5. There should be 100 nF decoupling capacitors on the power pins of all the single opamps.
  6. There is a low noise power daugther board made by Ben Abbott which you can use on the DCC. It should accept the direct power connector from the back panel and supply regulated power to the board.
  7. Take care to update the lower right hand corner info box with updated drawing version #'s and author name.
  8. The MAX4158 is 16 years old. It may be good if you can find a newer parts so it doesn't go obsolete.
  9. All of the R & C on the board should be sized 1206 for the SMD.
  10. For the whitening and AA filtering stages, we want the capability to use larger size parts (e.g. the red WIMA caps that are in the blue spinny box). So you will have to use larger footprints for those.
  11. The resistors should all be 0.1% thin film or metal film.
  12285   Sun Jul 10 17:33:00 2016 ericqUpdateGeneralVent progress

It took a little time, but I relocked the IMC and realigned to the point where the PRC is flashing, visible on REFL and AS, and tiny flashes are visible in TRY.

  12284   Sun Jul 10 15:54:23 2016 ericqUpdateCDSAll models restarted

For some reason, all of the non-IOP models on the vertex frontends had crashed.

To get all of the bits green, I ended up restarting all models on all frontends. (This means Gautam's coil tests have been interrupted.)

  12283   Sun Jul 10 15:38:01 2016 ericqUpdateGeneralETMX in guiderod/standoff gluing fixture

I was hoping to glue a standoff and guide rod today, but some problems have reared their heads. Story follows:

Upon first placng the optic into the standoff gluing fixture, I was presented with a geometric problem. In the assembly procedure, one glues the rods before the magnets, which prevents a situation like this:

When what you want to do is this:

So, I spun the optic around such that the magnet is on the far side of the scribe line from the side arm, and instead of extending the side arm past the scribe line, will bring it back towards the near side. I also swapped the arms of the fixture such that the guide rod will be glued on the opposite side of the optic than the side magnet, so the side magnet won't get in the way when doing the pitch adjustment of the second standoff.

Then, I found the scribed ruby rods, and took a look at one under a microscope. The groove looks nice and sharp. I placed the standoff in the side arm of the fixture.

However, the fact that the groove does not go all the way around the standoff leads to problem #1: when adjusting the position of the side arm, the standoff seems to roll around unpredictably, making it hard to deterministically position it while keeping the groove facing outwards. 

Problem #2 is not too surprising give Steve's finding about the guide rod holding arm in ELOG 12264. Given that the tip is banged up, the guide rod does not sit straight in the arm, making it crooked. This would lead to the second standoff's groove not being well aligned to the suspension wire.

I will meditate on solutions to these problems... I have covered the optic and fixture with the same foil hut Koji made on Friday.


Also, I peeked at the aluminum standoffs under the microscope. Since the groove goes all the way around, we don't really know where the wire was seated before. Still, there are some places where the groove looks kind of worn:

  12282   Fri Jul 8 22:26:03 2016 varunUpdateCDSDAFI Update: Changes in LSC model

I have added the control signals DARM_CTRL, MICH_CTRL, PRCL_CTRL, SRCL_CTRL, CARM_CTRL, XARM_CTRL, YARM_CTRL, MC_CTRL to the DAFI model from the LSC model via IPC commn.

The changes done to the LSC model include addition of an extra block going to DAFI (attachment 2, red rectangle in attachment 1), and addition of an extra overall output from the LSC, called DAFI_OUT2, which goes to DAFI through IPC link C1:LSC-DAF_2 (attach. 3). Now two distinct inputs can be given to the DAFI, whose intended purpose is to act as two distinct audio signals in the stereo output, but can also be used for arbitrary math. 

I am going to add the following PEM channels as DAF inputs subsequently, in a similar 2 input fashon.

SEIS_GUR1_X_OUT
SEIS_GUR1_Y_OUT
SEIS_GUR1_Z_OUT
SEIS_GUR2_X_OUT
SEIS_GUR2_Y_OUT
SEIS_GUR2_Z_OUT
SEIS_STS_1_X_OUT
SEIS_STS_1_Y_OUT
SEIS_STS_1_Z_OUT
ACC_MC1_X_OUT 
ACC_MC1_Y_OUT
ACC_MC1_Z_OUT
ACC_MC2_X_OUT
ACC_MC2_Y_OUT
ACC_MC2_Z_OUT

 

 

Attachment 1: lsc.png
lsc.png
Attachment 2: lsctodaf.png
lsctodaf.png
Attachment 3: lsctodaf1.png
lsctodaf1.png
  12281   Fri Jul 8 21:22:38 2016 gautamUpdateGeneralVent progress - ETMX SUS Coil driver electronics investigation

While ETMX is out, I'm leaving the larger amplitude excitations to the coils on over the weekend, in case any electronic glitch decides to rear its head over the weekend. The watchdog should be in no danger of tripping now that we have removed the ETM.

Unrelated to this work: while removing the ETMX suspension from the chamber, I also removed the large mirror that was placed inside to aid photo taking, so that there is no danger of an earthquake knocking it over and flooding the chamber with dust.

  12280   Fri Jul 8 21:15:03 2016 PrafulUpdateComputer Scripts / ProgramsMEDM Tab on Summary Pages

Thanks! Yes, only the screens that are not updated when the script is executed show this error. I'll try to keep debugging over the weekend.

Quote:

Very nice!

Some of the screens are up-to-date, and some are not. Are the errors associated with the screens that failed to get updated?

 

  12279   Fri Jul 8 21:02:09 2016 KojiUpdateComputer Scripts / ProgramsMEDM Tab on Summary Pages

Very nice!

Some of the screens are up-to-date, and some are not. Are the errors associated with the screens that failed to get updated?

  12278   Fri Jul 8 20:44:09 2016 KojiUpdateGeneralETMX removed from suspension

In the evening, I went into the clean room to check how it goes.

- The air around the table is quite warm like a hell. Is this normal?

- I checked how the scattered epoxy spots look like. They were not touching the bath anymore due to evaporation.
- I scraped the spots with the tweezers there. They were easily removed. The particlates on the side barrel were wiped by a wipe with aceton. (Result: Attachment 3)

- Then looked at the other side. I poked the standoff with the tweezer. It was easily removed. I don't think the bond was too weak. Just the area of the bond was so tiny.
- Also residue was scraped by a tweezer and wiped with a cloth. (Attachment 2)

- The removed stand off is in the stainless bowl together with the parts that Eric removed.

- I didn't want to leave the optic in the aceton fume. It was placed on a metal donuts for a 3" optic. (Attachment 4)

- I couldn't find a vacant clean glass jar for the lid. So, a foil hut was built. We should be very careful not to scratch the optic when we remove the hut. (Attachment 5)

- The aceton bath was covered with the foil as it was. (Attachment 6)

Attachment 1: photo1.jpg
photo1.jpg
Attachment 2: photo2.jpg
photo2.jpg
Attachment 3: photo3.jpg
photo3.jpg
Attachment 4: photo4.jpg
photo4.jpg
Attachment 5: photo5.jpg
photo5.jpg
Attachment 6: photo6.jpg
photo6.jpg
  12277   Fri Jul 8 19:33:16 2016 PrafulUpdateComputer Scripts / ProgramsMEDM Tab on Summary Pages

A new MEDM tab has been added to the summary pages (https://nodus.ligo.caltech.edu:30889/detcharsummary/day/20160708/medm/), although some of the screens are not updated when /cvs/cds/projects/statScreen/cronjob.sh is run. In /cvs/cds/projects/statScreen/log.txt, the following error is given for those files: import: unable to read X window image `0x20011f': Resource temporarily unavailable @ error/xwindow.c/XImportImage/5027. If anyone has seen this error before or knows how to fix it, please let me know.

In the meantime, I'll be working on creating an archive of MEDM screens for every hour to be displayed on the summary pages.

  12276   Fri Jul 8 16:33:26 2016 ericqUpdateGeneralETMX removed from suspension

The magnet, guide rod, and standoff came off without too much force. However, some epoxy residue remains on the barrel. I didn't really want to scrape it off, so I've opted for more soaking. Much of the acetone had evaporated already, so I put some more - just to the point where the residue is submerged. 

  12275   Fri Jul 8 15:44:07 2016 PrafulUpdateElectronicsReplacing DIMM on Optimus

Optimus' memory errors are back so I found the exact DIMM model needed to replace: http://www.ebay.com/itm/Lot-of-10-Samsung-4GB-2Rx4-PC2-5300P-555-12-L0-M393T5160QZA-CE6-ECC-Memory-/201604698112?hash=item2ef0939000:g:EgEAAOSwqBJXWFZh I'm not sure what website would be the best for buying new DIMMs but this is the part we need: Samsung 4GB 2Rx4 PC2-5300P-555-12-L0 M393T5160QZA-CE6.

  12274   Fri Jul 8 14:03:26 2016 ericqUpdateGeneralETMX removed from suspension

ETMX is currently in the clean room, the barrel is the tiniest bit submerged in acetone that will remove a guide rod, standoff, and side OSEM. 

Additional inpsection of the standoffs on the flow bench did not provide any insight, pictures are in picasa. Here is a cropped version of a picture we took:

 

We should look at them under a microscope.

  12273   Fri Jul 8 13:01:23 2016 AakashUpdateGeneralAcromag is talking ! | SURF 2016

Acromag is talking now, after few changes to the original EPICS configuration and cross compile configuration. Modbus config files also were changed and compiled again to run it on linux-arm architecture. I have made use of pyModbus for the final work and I am planning to use the same for grabbing channels. Though I am unable to grab channel data right now, I am able to communicate to it over ethernet and send and receive data. 
 

  12272   Fri Jul 8 11:48:09 2016 KojiUpdateGeneralVent progress - ETMX SUS Coil driver electronics investigation

YES

Move the suspension on the south clean bench and make more close inspection. We need to remove the OSEMs.

Then unmount the mirror. Bring it to the clean room and work on the bond removal.
Meanwhile, set up all suspension components inclusing the alignment test setup.

  12271   Fri Jul 8 11:35:45 2016 gautamUpdateGeneralVent progress - ETMX SUS Coil driver electronics investigation

Yesterday, I expanded the extent of the ETMX suspension coil driver investigation. I set up identical monitors for two more coils (so now we are monitoring the voltage sent to UL, UR and LL - I didn't set one up for LR because it is on a second DB25 connector). Furthermore, I increased the excitation amplitude from ~20 to ~2000 (each coil had an independent oscillator at slightly different frequency between 5Hz and 8.5 Hz), the logic being that during LSC actuation we send signals of approximately this amplitude to the coils and we wanted to see if a larger amplitude signal somehow makes the system more prone to glitches.

Over ~10 hours of observation, there is no clear evidence of any glitch. About 2 hours ago (~930am PDT Fri Jul 8), the watchdog tripped - but this was because even though I had increased the trip threshold to ~800 for the course of this investigation, megatron runs this script every 20 minutes or so that automatically reduces this threshold by 17 counts - so at some point, the threshold went lower than the coil voltage, causing the watchdog to trip. So this was not a glitch. The other break around 2am PDT earlier today was an FB crash.

Do we now go ahead and pull the suspension out, and proceed with the swap?

Attachment 1: coilGlitchMon.png
coilGlitchMon.png
  12270   Thu Jul 7 17:12:50 2016 JohannesUpdateGeneralVent progress

I performed a visual inspection of ITMY in its natural habitat today. I did not get any great pictures from the HR side because it's located very towards the edge of the table towards the arm. Before that I checked the levelness of the table. East-west direction was fine, north-south was slightly off but still within the marks for 'level'.

The AR side had several speckles, a few of them located somewhat near the geometrical center of ITMY. The top of the barrel was worse of, as expected. The HR side was a little better, but there were a few pieces of dust? near near the center. Sample pictures are attached, I uploaded all the good ones to Picasa.

Clamps that mark the position of ITMY were already in place. I did not move the optic just yet, and we will have to move a cable block out of the way to bring ITMY near the opening for us to work on it. We will markt the position of that to preserve the weight distribution. Then we can probably take some better before/after pictures. Tomorrow I will be looking at ETMY.

  12269   Thu Jul 7 16:05:55 2016 KojiUpdateGeneralSUS Vmon

Ah, thanks. That makes sense. In that case, we should remove the texts "30Hz HPF" from the suspension screens.

Now we just need AA LPFs for these channels, or hook them up to the RT system.

  12268   Thu Jul 7 15:23:39 2016 ericqUpdateGeneralSUS Vmon

Based on Koji's observation of a flat TF, it seems more likely the Vmon channels are looking at the path I've highlighted in green (named "EPICS V Mon"), rather than the path in red (named "DAQ Mon") that Koji initially suspected. This path still lacks any AA for the 16Hz EPICS sampling.

  12267   Thu Jul 7 14:45:26 2016 KojiUpdateGeneralpianosa monitor dead

Johannes, Koji

We obtained two monitors of the same type from Larry.

  12266   Thu Jul 7 12:44:52 2016 varunUpdateCDSDAFI update

Attached is a diagram, showing the entire (planned) signal flow of the DAF model. Some thoughts on the implementation after discussion with eric:

1) Since the LSC control signals and ASC signals are running on the c1lsc FE at the same rate as DAFI (16kHz), it would be wise to start from these.

   Current implementation: has a matrix at the end of the LSC PD signals, which selects one of the PD signals and outputs it to the DAFI via IPC communication.

    Proposed Changes: Add another matrix at the end of the LSC PD signals, to give to the second stereo output. Similarly, add two matrices each at the end of the LSC control signals and     the ASC signals. Each matrix must select one of the signals and output it to the DAF via IPC.

2) The PEM running on the c1sus FE system will have to be brought to DAFI in a similar fashon. However, since c1sus runs at 2kHz, there is a possibility of imaging while the signal is    transfered to the DAFI. This could be taken care of by an anti imaging filter, or inserting zeros between two samples coming at to the 16 kHz system from the 2kHz system and then low-passing it to remove the aliased parts. (similar to upsampling)

3) For the SUS control signals, input can be given from a matrix prepared for each optic seperately.

Attachment 1: DAFI.pdf
DAFI.pdf
  12265   Thu Jul 7 10:49:03 2016 gautamUpdateGeneralVent progress - ETMX SUS Coil driver electronics investigation
Quote:

It may be advantageous to look at the coil output data from when the OSEM damping is on, to try and reproduce the real output signal amplitude that gets sent to the coils.

The amplitude of the applied signal (20) was indeed chosen to roughly match what goes to the coils normally when the OSEM damping is on.

There appears to be no evidence of a detectable glitch in the last 10 hours or so (see attachment #1 - of course this is a 16Hz channel and the full data is yet to be looked at)... I guess the verdict on this is still inconclusive.

Attachment 1: UL_glitchMon_Striptool.png
UL_glitchMon_Striptool.png
  12264   Thu Jul 7 09:13:54 2016 SteveUpdateSUSSOS gluing fixture

Atm 1, It's right arm is perfect.

Atm 3-4, The left one has bended (dropped) end.

Atm 2, Our ruby wire stanoffs will fit the jig. Ruby OD 1.27 mm vs. old Aluminum OD 1.0 mm. Length ruby 6.4 mm vs Al 4.8 mm

Atm 5, The fixture translation stages are a bit loooose. Careful use of the micrometer is needed to be precise

Betsy agreed that the 40m will keep SOS fixtures.

Attachment 1: SOSgluingFixRarmWend.jpg
SOSgluingFixRarmWend.jpg
Attachment 2: SOSgluingFixRarm.jpg
SOSgluingFixRarm.jpg
Attachment 3: SOSgluingFixLarm45.jpg
SOSgluingFixLarm45.jpg
Attachment 4: SOSgluingFixLarm.jpg
SOSgluingFixLarm.jpg
Attachment 5: SOSgluingFixture.jpg
SOSgluingFixture.jpg
  12263   Thu Jul 7 00:25:07 2016 ericqUpdateGeneralVent progress - ETMX SUS Coil driver electronics investigation

It may be advantageous to look at the coil output data from when the OSEM damping is on, to try and reproduce the real output signal amplitude that gets sent to the coils.

  12262   Wed Jul 6 23:01:03 2016 gautamUpdateGeneralpianosa monitor dead

One of the pianosa monitors has ceased to function frown For now, it has been set up to operate with just the one monitor.

One of Donatella's monitors has a defective display as well. Maybe we should source some replacements. Koji has said we will talk to Larry Wallace about this..

  12261   Wed Jul 6 22:58:01 2016 gautamUpdateGeneralVent progress - ETMX SUS Coil driver electronics investigation

I've made a few changes to the monitoring setup in the hope we catch a glitch in the DAC output/ sus coil driver electronics. Summary of important changes:

  1. I'm using a CDS oscillator to send a signal of 20counts amplitude, 5.0 Hz to the coil rather than an excitation point. This way, I have access to the known signal we are sending, and can subtract it from the measured signal. 
  2. To account for the phase delay between the excitation from the oscillator to the measured excitation, I am using an all-pass filter to manually delay the oscillator signal (internally in the model) before subtracting it from the measured output.

It remains to see if we will actually be able to see the glitch in long stretches of data - it is unclear to me how big a glitch will be in terms of ADC counts.

The relevant channels are : C1:SCX-UL_DIFF_MON and C1:SCX-UL_DIFF_MON_EPICS (pardon the naming conventions as the setup is only temporary after all). Both these should be hovering around 0 in the absence of any glitching. The noise in the measured signal seems to be around 2 ADC counts. I am leaving this as is overnight, hopefully the ETMX coil drive signal chain obliges and gives us some conclusive evidence...

I have not committed any of the model changes to the SVN. 

  12260   Wed Jul 6 21:50:21 2016 KojiUpdateComputer Scripts / ProgramsNew Tabs and Working Summary Pages

It seemed something has been done. And I got cron emails.
Then, it seemed something has been done. And the emails stopped.

  12259   Wed Jul 6 21:16:17 2016 Max IsiUpdateComputer Scripts / ProgramsNew Tabs and Working Summary Pages

This should be fixed now—apologies for the spam.

Quote:

I don't know much about how the cron job runs, I'll forward this to Max.

Quote:

I started to receive emails from cron every 15min. Is the email related to this? And is it normal? I never received these cron emails before when the sum-page was running.

 

 

  12258   Wed Jul 6 21:09:09 2016 not KojiUpdateComputer Scripts / ProgramsNew Tabs and Working Summary Pages

I don't know much about how the cron job runs, I'll forward this to Max.

Quote:

I started to receive emails from cron every 15min. Is the email related to this? And is it normal? I never received these cron emails before when the sum-page was running.

Max says it should be fixed now. Have the emails stopped?

  12257   Wed Jul 6 21:05:36 2016 KojiUpdateComputer Scripts / ProgramsNew Tabs and Working Summary Pages

I started to receive emails from cron every 15min. Is the email related to this? And is it normal? I never received these cron emails before when the sum-page was running.

Attachment 1: cron_mail.txt.zip
  12256   Wed Jul 6 20:51:00 2016 KojiUpdateGeneralSeismometer Enclosure Development | SURF 2016

Circuit1: It is nice to receive the voltage across the transimpedance resistor with a high impedance buffer (or amplifier), as close to the resister as possible. This amplifier needs to have low numbers for input bias current, input offset current, and input current noise. These current noise becomes the noise of the temperature reading. On the top of that, the input voltage noise of the buffer will be added to the output. The typical noise model can be found in http://www.analog.com/media/en/technical-documentation/application-notes/AN-940.pdf

The good candidates for the buffer is LT1128, ADA4004, OPA140, and LT1012. If the application is not too sensitive to the total noise, OPA604 is a good choise with easier handling.

Circuit2: With the same reason, AD741 is an old generic amp that is not a great choise for this purpose. The current noise is more significant because of the higher transimpedance here. The same noise model as above can be used to analyze the performance.

  12255   Wed Jul 6 19:36:45 2016 KojiUpdateGeneralSUS Vmon

I wanted to know what this Vmon exactly is. D010001 is telling us that the Vmon channels are HPFed with fc=30Hz (Attachment 1). Is this true?


I checked the quiscent noise spectrum of the ITMX UL coil output (C1:SUS-ITMX_ULCOIL_OUT) and the corresponding VMON (C1:SUS-ITMX_ULVmon). (Attachment 2 Ref curves). I did not find any good coherence. So the nominal quiscent Vmon output is carrying no useful information. 

Question: How much do we need to excite the coil output in order to see any meaningful signal?

As I excite the ITMX UL coil (C1:SUS-ITMX_ULCOIL_EXC) with uniform noise of 100-300 counts below 0.3Hz, I eventually could see the increase of the power spectrum and the coherence (Attachment 2). Below 0.1 Hz the coherence was ~1 and the transfer function was measured to be -75dB and flat. But wait, why is the transfer function flat?

In fact, if I inject broadband noise to the coil, I could increase the coil output and Vmon at the same time without gaining the coherence. (Attachment 3). After some more investigation, I suspect that this HPF is diabled (= bypassed) and aliasing of the high freq signal is causing the noise in Vmon.

In order to check this hypothesis, we need to visit the board.

Attachment 1: HPF.png
HPF.png
Attachment 2: 160706_ITMX_VMON2.pdf
160706_ITMX_VMON2.pdf
Attachment 3: 160706_ITMX_VMON1.pdf
160706_ITMX_VMON1.pdf
  12254   Wed Jul 6 17:17:22 2016 PrafulUpdateComputer Scripts / ProgramsNew Tabs and Working Summary Pages

The main C1 summary pages are back online now thanks to Max and Duncan, with a gap in pages from June 8th to July 4th. Also, I've added my new VMon and Sensors tabs to the SUS parent tab on the main pages. These new tabs are now up and running on the July 7th summary page.

Here's a link to the main nodus pages with the new tabs: https://nodus.ligo.caltech.edu:30889/detcharsummary/day/20160707/sus/vmon/

And another to my ldas page with the tabs implemented: https://ldas-jobs.ligo.caltech.edu/~praful.vasireddy/1150848017-1150848317/sus/vmon/

Let me know if you have any suggestions or see anything wrong with these additions, I'm still working on getting the scales to be right for all graphs.

  12253   Wed Jul 6 16:40:09 2016 AakashUpdateGeneralSeismometer Enclosure Development | SURF 2016

I am using AD592CNZ temperature transducer ICs for measuring temperature inside as well as outside the enclosure. It is a  current output IC which outputs current proportional to temperature. As mentioned in the data sheet of AD592, I am using the following two schematics:

 

Though I still need to calibrate these temperature transducers, I did some measurements. I have temperature readings, and now my goal in few days is to find a transfer function of temperature fluctuations inside the enclosure to outside the enclosure.

 

About data acquisition:

We have re-configured the raspberry pi(B8:27:EB:70:D0:D8) on martian network. It's new ip address is 192.168.113.107(domenica.martian). Also, we have added the Acromag Busworks card(00:01:C3:00:9F:C8) on the martian network and its ip address is 192.168.113.237(acroey.martian).   

  12252   Wed Jul 6 11:02:41 2016 PrafulUpdateComputer Scripts / ProgramsVMon Tab on Summary Pages

I've added a new tab for VMon under the SUS parent tab. I'm still working out the scale and units, but let me know if you think this is a useful addition. Here's a link to my summary page that has this tab: https://ldas-jobs.ligo.caltech.edu/~praful.vasireddy/1151193617-1151193917/sus/vmon/


I'll have another tab with VMon BLRMS up soon.

Also, the main summary pages should be back online soon after Max fixed a bug. I'll try to add the SUS/VMon tab to the main pages as well.

  12251   Wed Jul 6 10:58:29 2016 VarunUpdateCDSDAFI review

The DAFI block was reviewed by Rana yesterday. The following changes/improvements were suggested: (Updated on 20th July 2016 with tasks taat remain in red)

1) include all the various channels like PEM, LSC, ASC, SUS, SEI, etc. as the inputs. Currently the inputs are only the LSC.
2) include all the control signals.
3) create a very detailed diagram of the entire signal flow and plan tasks accordingly.
4) Enable cascading of various DSP processes.
5) Adjusting the gain of the AGC such that the amplitude of the output signal comes to about half the peak amplitude offered by the ADC. This will help taking advantage of the entire dynamic range of the ADC.
6) change the enable button styles from a text input based controller to a button controller.
7) Currently, disabling a particular signal terminates the signal. Instead, it should turn into a unity gain block on disabling.
8) Check if the Fibox does AC coupling or not. If not, add an AC coupling arrangement in the DAFI.
9) Check the nature of the ADC1 and ADC2 inputs to the DAFI. I checked them yesterday, and they are channels 25 and 26 of ADC0, which are empty.

  12250   Wed Jul 6 10:58:07 2016 SteveUpdateVACvent 78 valve configuration

Vacuum Status: Chamber Open

All chamber annuloses are vented.  Vac Monitor screen is not communicating with gauges. The valve position indicator are working.

RGA is pumped by Maglev through VM2

 

Attachment 1: CamberOpen.png
CamberOpen.png
ELOG V3.1.3-