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ID Date Author Typeup Category Subject
  16439   Thu Oct 28 23:13:19 2021 YehonathanUpdateBHDSOS assembly

{Tega, Yehonathan, Koji}

Suspension of a Dummy Optic

We gathered the components needed for suspending a 2" optic housed in a 3" ring adapter:

1. SOS Tower

2. Winches+Winch adapter plate (Attachment 3)

2. HeNe Laser + Power supply

3. A steering mirror

4. QPD + ND2 Filter + Electronic amplifier

5. Oscilloscope

6. Dummy optic housed in a ring adapter (Attachment 2)

An OpLev was built using the HeNe laser, steering mirror, suspended optic, QPD (Attachment 1).

The beam height was set with a ruler. The QPD was placed in front of the laser and its height was adjusted until the Y signal vanished.

The beam was made parallel to the table. First, roughly by using an iris. Then, more accurately, by measuring the beam directed at the suspended optic with the QPD and zeroing the Y signal by adjusting the steering mirror.

We suspended the dummy optic using a music wire we found in the cleanroom cabinet.

All the wire clamps on the ring adapter, SOS, and winches were loosened.

About 0.5m of music wire was cut. Then, the wire was threaded through the wire clamp on the adapter side block, around the ring adapter, and through the wire clamp on the other side block, keeping the wire untwisted. The optic was put on the safety stop and the height was roughly adjusted using the lower EQ stops.

The wire pair was then threaded through the wire clamp on the suspension block and held near the winches. The wire was made to go through the groves at the side blocks. The wire was clamped to the side blocks. The wires were clamped on the winches. The wires were pulled by the winches until the magnet marking on the side blocks was centered on the OSEMs' holes on the side plates of the SOS (attachment 4).

Once the heights were set, the wire was clamped at the suspension block.

We balanced the dummy optic using a counterweight.

We placed the QPD at the laser reflection from the optic. We adjusted the screw set going through the counterweights to adjust the balance. The pitch imbalance was monitored by observing the Y signal on the oscilloscope.

Comments:

1. Turns out that for a 1/4" thick optic, the rear counterweight needs to be removed for achieving balance.

2. To fix the counterweight on the setscrew we will use some epoxy.

3. Seems like the left optical table in the cleanroom is slightly tilted. We need to fix it.

4. The bottom long EQ stop is not touching the adapter due to the balancing mass socket. We might want to put a nut on it.

5. Still need to glue 3 more side magnet+dumbell assemblies to rods and then glue them before gluing them to the side blocks which will take at least 2 more days until we can start suspending a real optic.

  16442   Mon Nov 1 14:51:34 2021 KojiUpdateGeneralChecking the vent plan

The vent team described a detailed vent plan (and reports where the actions have been performed)

https://wiki-40m.ligo.caltech.edu/vent/Fall2021

- [Sec.4] We should decide the final PR2 mirror through table-top measurements.

- [Sec 6] BS alignment is probably "unknown" now. So it'd be better to use the ITMY spot as the reference, then align BS for ITMX. For temporary alignment, it's OK though.

- [Sec 9-11] RIght now there is no mounts to place LO3/LO4/AS2/AS3/BHDBS. But we probably want to test something before the installation of the BHD? Just place the BHDBS on a optics mount so that we get an interfered beam on ITMY?

At this point we are supposed to have all the electronics all the CDS necessary for the new SOS control. Otherwise, they are just swinging and the alignment work will just be impossible.

- [Sec 15] The OPLEV mirrors can be freely moved as long as it does not block the main IR beams. Moving ITMXOL1 makes the reflection blocked by ITMXOL2. And moving ITMXOL2 would make the IR beams clipped. Consider replacing the mounts with a fixed mount. (The OPLEV mirrors are 1.5" in dia. It is not common vacuum compatible 1.5inch mounts. If 1" Al mirror is sufficient, we can use it.

https://wiki-40m.ligo.caltech.edu/vent/Fall2021/FinalAlignment

- The arms are the most strict alignment requirement. Everything else will follow the arm alignment. So start from the arms and propagate the alignment to Michelson / PRMI / SRMI.

- We reestablish arm alignment using the end green beams.

- Then recover IR arm alignment. Consider using ASS if possible

  16443   Tue Nov 2 15:02:03 2021 YehonathanUpdateBHDSOS assembly

{Yehonathan, Tega}

We took the free-swinging spectra of the OpLev in the X and Y direction.

To make the motion of the optic quiet we turned off the airflow on the optical bench and moved the QPD close to the SOS so that the laser beam stays more or less within the QPD sensitive area.

In the process, we realized that the cleanroom HeNe went bad. It turned off after a few minutes after turning it on. The behavior repeated with another power supply. We replaced the HeNe and realigned it coarsely.

The data was taken using an oscilloscope while the optic was swinging freely. The PSD was calculated afterward (attachment 1).

Surprisingly, the pitch has a resonance frequency of ~ 2.5 Hz. And this is after we removed the back counterweight.

Additionally, we aligned the tilt of the optical table. Using a spirit bubble we adjusted the tilt by using a wrench on the table legs. As we suspected, the table was slightly tilted in the north-south direction.

  16445   Tue Nov 2 18:54:41 2021 Anchal, PacoUpdateBHDOptical fibres laid for BHD upgrade

We successfully laid down all required optical fibre fiber cables from 1X4-1X7 region to 1Y1-1Y3 region today. This includes following cables:

  • Timing fibre fiber from Master Timing Synchornizer D050239 on 1X6 to C1SU2 I/O chassis on 1Y1.
  • Timing fibre fiber from Master Timing Synchornizer D050239 on 1X6 to C1BHD I/O chassis on 1Y3.
  • CX4 cable from Dolphin Card on 1X4 to C1SU2 FE on 1Y1 for IPC.
  • CX4 cable from Dolphin Card on 1X4 to C1BHD FE on 1Y3 for IPC.
  • DAQ Network extension fibre fiber optic cable from DAQ Network Switch on 1X7 to another switch we mounted on 1Y3 for local DAQ network distribution.
  16446   Tue Nov 2 22:50:30 2021 KojiUpdateBHDSOS assembly

2.5Hz is surprising. Can you move it down to sub 1Hz by adding a socket cap screw at the top instead of the set screw for the Teflon piece? How much mass do you need to add?

  16449   Thu Nov 4 18:29:51 2021 TegaUpdateSUSSetting up suspension test model

[Ian,Tega]

Today we continued working on setting up the 6 degrees of freedom model for testing the suspension which we copied over from  "/cvs/cds/rtcds/userapps/release/sus/c1/models/c1sup.mdl" to c1sp2.mdl in the same folder. We then changed the host from c1lsc to c1sus2, changed cpu # from 7 to 3 bcos c1sus2 has 6 cores. Then ran the following commands to build and install the model on c1sus2:

$ ssh c1sus2

$ rtcds make c1sp2

$ rtcds install c1sp2

where we encountered the following installation error:

ERROR: This node 62 is already installed as:

hostname=c1lsc

system=c1sup

The new entry you are trying to write is as follows:

hostname=c1sus2

system=c1sp2

This script will not overwrite existing entries in testpoint.par

If this is an attempt to move an existing system from one host to another,

please remove conflicting entry from testpoint.par file

It seems that changing the model name and host did not change the node allocation, so will remove the previous entries in testpoint.par to see if that helps. After deleting the following lines

[C-node62]
hostname=c1lsc
system=c1sup

from the file "/opt/rtcds/caltech/c1/target/gds/param/testpoint.par", the installation went fine and the above entries were replaced by 

[C-node62]
hostname=c1sus2
system=c1sp2

BTW, I now believe the reason we had the node conflict earlier was bcos both models still had the same value of  dcuid=62, so I think changing this value in our model file would be a better solution. Work is ongoing.

 

  16451   Fri Nov 5 12:49:32 2021 ranaUpdateSUSSetting up suspension test model

Please don't put it on c1sus2. Put it on the completely independent test stand as we discussed Wednesday. You must test the controller on the simplant and verify that they thing is stable and works, before putting it in the 40m network.

  16452   Fri Nov 5 20:35:10 2021 KojiUpdateBHDFeedthru / Optical Mounts

- New feedthrus [4xDB25 Qty 4 / 8xDB25 Qty 1] are placed on the wire shelf at the entrance -> Jordan, please clean them.

- There are plenty of 2" DLC mounts. There are also many 1.5" mounts but they are less useful.
  We need at least 3 1" moounts and 1 1" or 2" lens mount (and the lens). Let's purchase them on Thorlabs. I'll work on the order.

  16456   Mon Nov 8 17:22:27 2021 YehonathanUpdateBHDSOS assembly

Big Gluing Day

Today I glued the magnet+dumbell assemblies on the optics adapters.

Unlike magnet gluing on a 3" optic where one can use a magnet gluing fixture, here I had to position the magnets manually. There is a complication though: the magnet is much heavier than the dumbell making it almost impossible gluing the dumbell side down onto the adapter since it is very unstable in this position. A workaround is to put the magnets on some paramagnetic sheet so that the magnets stick to it and then flip it over and glue it on the adapter dumbell sides down.

The problem here is that I need to position the magnets relatively accurately on the metal sheet. To make things slightly easier I printed some drawings of the positions of the magnet, laminated them, and cleaned them to have a decent starting point (attachment 1).

For each adapter:

1. I applied glue to the 4 circular grooves at the back of the adapter.

2. I picked 4 magnets (2 north, 2 south). Trying to match their strength.

3. Made a note of which magnets I picked for which adapter in the magnet+dumbell spreadsheet.

4. Clean the dumbells' surfaces when necessary.

5. Put the magnets on a laminated magnet-positions-drawing on a metal sheet that was precleaned in the right order.

6. Flip the metal sheet and position it on the adapter such that the dumbells go as precisely as possible into the circular grooves on the adapater.

7. Adjust the magnets' positions by pushing them slightly with a non-magnetic tip.

Attachment 2 shows the numbering on the adapters for future tracking.

I also glued some magnets and aluminum rods to side blocks. Next gluing session I will glue magnets to the aluminum rods. Probably some dumbells will not stick well to the adapters. These will have to be cleaned and reglued as well.

 

 

  16457   Mon Nov 8 17:52:22 2021 Ian MacMillanUpdateSUSSetting up suspension test model

[Ian, Tega]

We combined a controler and a plant model into a single modle (See first attachment) called x1sus_cp.mdl in the userapps folder of the cymac in c1sim. This model combines 2 blocks: the controler block which is used to control the current optics and is found in cvs/cds/rtcds/userapps/release/sus/c1/models/c1sus.mdl further the control block we are using comes from the same path but from the c1sup.mdl model. This plant model is the bases for all of my custom plant models and thus is a good starting point for the testing. It is also ideal because I know it can beeasily altered into a my state-space plant model. However, we had to make a few adjustments to get the model up to date for the cds system. So it is now a unique block.

These two library blocks are set in the userapps/lib folder on the cymac. This is the lib file that the docker system looks to when it is compiling models. For a quick overview see this. All other models have been removed from the MatLab path so that when we open x1sus_cp.mdl in MatLab it is using the same models it will compile with.

We could not find the rtbitget library part, but chris pointed us to userapps, and we copied it over using: scp /opt/rtcds/userapps/trunk/cds/common/models/rtbitget.mdl controls@c1sim:/home/controls/simLink/lib.

NOTE TO FUTURE IAN: don't forget that unit delays exist.

Next step: now that we have a model that is compiling and familiar we need to make medm screens. We will use the auto mdl2adl for this so that it is quick. Then we can start adding our custom pieces one by one so that we know that they are working. We will also work with Raj to get an independent python model working. Which will allow us to compare the cds and python models.

  16459   Tue Nov 9 11:11:37 2021 YehonathanUpdateBHDSOS assembly

The gluing was mostly successful. Only two magnets didn't stick (see attachment).

  16465   Fri Nov 12 23:47:29 2021 YehonathanUpdateBHDSOS assembly

{Tega, Yehonathan}

First attempt at the suspension of a Lambda Optic mirror

We found the box with the 2" Lambda Optic mirrors in the cleanroom. We choose to suspend a mirror with a ROC = 5m, probably LO1.

The mirror was put inside an adapter that was prepared beforehand, put the mirror in place by tightening the Teflon rod, and then clamp it using the clamping pads.

We decided to cut two wires and clamp them to the side blocks of the adapter, while it sits on the EQ stops. The wires were threaded through the winches' clamps, through the wire clamp on the suspension block, and through the side blocks' wire clamps. We adjusted the wire position while pulling on it. The wire was made to sit inside the wire grooves on the side blocks. While tightening the clamp on the side block with the magnet, the LN key fell knocking off two magnets from the back of the adaptercrying.

Next time we think it might be a better idea to do all the adapter wire clamping on the table instead of on the SOS tower.

In the meanwhile, here are some pictures from today.

 

  16470   Tue Nov 16 17:42:46 2021 YehonathanUpdateBHDSOS assembly

{Tega, Yehonathan}

Another attempt at the suspension of a Lambda Optic mirror

The lambda mirror was removed from the adapter whose magnets were knocked off. We tried to mount the mirror on a different adapter but we knocked off magnets from two adapters crying. We succeeded in mounting the mirror at the third attempt (Adapter number 6). In the meanwhile, Tega threaded wires through side blocks separated from the adapter. He positioned the wires inside the grooves of the side block under a microscope (attachment 1). This procedure is much more accurate and pain-free than doing it on the suspended mirror.

We took the adapter and put it on the EQ stops. The wires were threaded through the wire clamp on the suspension block and clamped at the winches.

The adapter was rotated until the side magnet was roughly at the center of the side OSEM port. We then, as before, put coils in OSEM ports and try to adjust the height of the side magnet and the magnet groove on the other side block such that they are roughly at the center of the coil. We used the winches for fine adjustment.

I used the Canon camera to make sure the side blocks are leveled (attachment 2). I used the macro lens for that purpose. I set up a live stream from the Canon camera using these instructions only that I use OBS instead of CamTwist. I painted a semi-transparent green rectangle to annotate the position of the side magnet socket (attachment 3). I did this several times to confirm the repeatability of the results. Again using the winches for fine adjustments.

Once the height of the side magnets was confirmed to be leveled. I clamped the wires to the suspension block and cut them above it.

I tried to balance the optic but again I see that the suspensions are hysteretic. I check to see whether the wire is touching anything and indeed it touches the corner of the side blockcryingcryingcrying (attachments 4, 5).

 

 

 

  16471   Tue Nov 16 18:28:53 2021 KojiUpdateBHDSOS assembly

Yehonathan told me that the wires are touching between the clamps! I went back to the CAD and confirmed it is really happening. Sad.

The distance of the wires at the upper clamp is 17.018mm.
The distance of the lower clamps is 74.168mm
The vertical drop of the wire is 251mm
--> The wire angle from the vertical line is 0.114 rad

The lower wire block has a step of 1.016mm with the vertical extension of the piece by 11.684mm
--> The angle clearance of the lower clamp is 0.087 rad

So the clearance was not enough.

If we cut the top center of the wire block more than 2.77mm, we can make the wires free.
For safety, we can cut 0.25" = 6.35mm. This will give 0.4mm clearance between the block and the wire at the closest point.

I did this modification on the 3D model and modified the 2D drawing too, so that we can find the machine shop to do it quickly.

  16472   Wed Nov 17 07:32:48 2021 ChubUpdateGeneralwire clamp plate mod

This will be difficult to modify with the magnets and dumbells in place.  Even if someone CAN clamp this piece into an endmill machine with the magnets/dumbells in place, the vibration of the cutting operation may be enough to break them off.

  16473   Wed Nov 17 11:53:27 2021 KojiUpdateGeneralwire clamp plate mod

Of course, we remove the magnet-dumbbell for machining. After that the part will be cleaned/baked again. And Yehonathan is going to glue the magnet-dumbbell again.

  16474   Wed Nov 17 17:37:53 2021 AnchalUpdateGeneralPlaced Nodus and fb1 on UPS power

Today I placed nodus and fb1 on UPS battery backed supply. Now power glitches should not hurt our cds system.

  16476   Thu Nov 18 15:16:10 2021 AnchalUpdateGeneralMoved Chiara to 1X7 above nodus powered with same UPS

[Anchal, Paco]

We moved chiara to 1X7 above nodus and powered with same UPS from a battery backed port. The UPS is at 40% load capacity. The nameserver and nfs came back online automatically on boot up.

 

  16479   Mon Nov 22 17:42:19 2021 AnchalUpdateGeneralConnected Megatron to battery backed ports of another UPS

[Anchal, Paco]

I used the UPS that was providing battery backup for chiara earlier (a APS Back-UPS Pro 1000), to provide battery backup to Megatron. This completes UPS backup to all important computers in the lab. Note that this UPS nominally consumes 36% of UPS capacity in power delivery but at start-up, Megatron was many fans that use up to 90% of the capacity. So we should not use this UPS for any other computer or equipment.

While doing so, we found that PS3 on Megatron was malfunctioning. It's green LED was not lighting up on connecting to power, so we replaced it from the PS3 of old FB computer from the same rack. This solved this issue.

Another thing we found was that Megatron on restart does not get configured to correct nameserver resolution settings and loses the ability to resolve names chiara and fb1. This results in the nfs mounts to fail which in turn results in the script services to fail. We fixed this by identifying that the NetworkManager of ubuntu was not disabled and would mess up the nameserver settings which we want to be run by systemd-resolved instead. We corrected the symbolic link: /etc/resolv.conf -> /run/systemd/resolve/resolv.conf. the we stopped and diabled the NetworkManager service to keep this persistent on reboot. Following are the steps that did this:

> sudo rm /etc/resolv.conf
> ln -s /etc/resolv.conf /run/systemd/resolve/resolv.conf
> sudo systemctl stop NetworkManager.service
> sudo systemctl disable NetworkManager.service

 

  16480   Tue Nov 23 18:02:05 2021 AnchalUpdateIMCMC autolocker shifted to python3 script running in docker

I finished copying over the current autolocker bash script functionality into a python script which runs using a simple configuration yaml file. To run this script, one needs to ssh into optimus and :

controls@optimus|~> cd /opt/rtcds/caltech/c1/Git/40m/scripts/MC
controls@optimus|MC> sudo docker-compose up -d
Creating mc_AL_MC_1 ... done

That's it. To check out running docker processes, one can:

controls@optimus|MC> sudo docker ps

And to shut down this particular script, in the same directory, one can

controls@optimus|MC> sudo docker-compose down
Removing mc_AL_MC_1 ... done

If the docker image requires to be rebuild in future, go to the directory where Dockerfile is present and run:

controls@optimus|MC> sudo docker build -t pyep .

I had to add PyYAML package in the pyepics docker image already present on docker hub, thanks to Andrew.

For now, I have disabled the MCautolocker service on Megatron. To start it back again, one would need to ssh into megatron and do following:

~> sudo systemctl enable MCautolocker
~> sudo systemctl start MCautolocker

Let's see for a day how this new script does. I've left PSL shutter open and autolocker engaged.

To do: Fix the C1:IFO-STATE epics channel definition so that it takes its bits from separate lock status channels instead of scripts writign the whole word arbitrarily.

  16483   Wed Nov 24 14:15:15 2021 YehonathanUpdateBHDSOS assembly

Late update. We got 2 modified side blocks from Jordan a few days ago. Yesterday, I glued a side magnet to one of the modified side blocks.

I took the opportunity to reglue some magnets that were knocked off from the adapters. I did this for 2 adapters only since w need 4 shallow adapters and we already had 2 complete ones.

Today, Jordan gave us the rest of the modified side blocks clean and baked. We are ready to suspend a mirror today.

  16484   Wed Nov 24 14:34:15 2021 YehonathanUpdateBHDSaving on SUSAUX slow channels

Koji found out that the stock for BIO Acromag modules is very low and that the lead time for ordering new ones is ~ 1-year X-o.

We figure we might need to minimize the number of modules but still keep the Acromag chassis functional.

 

Looking at the new C1AUXEY feed-throughs spreadsheet one can see that we actually normally need only 1 BIO (not 2) module since there are 16 suspensions related bios + 1 green shutter which is unrelated to SUSAUX so there is no room to cut back here.

 

There are 16 analog input channels, 5 for PDMONs and 5 VMONs, and 6 spares which require 2 ADCs. Removing the spares and 2 monitoring channels will be enough to get us to 1 ADC.

  16488   Tue Nov 30 17:11:06 2021 PacoUpdateGeneralMoved white rack to 1X3.5

[Paco, Ian, Tega]

We moved the white rack (formerly unused along the YARM) to a position between 1X3, and 1X4. For this task we temporarily removed the hepas near the enclosures, but have since restored them.

  16489   Wed Dec 1 12:57:08 2021 YehonathanUpdateBHDSOS assembly

{Yehonathan, Tega}

We glued some magnets onto modified side blocks. We followed pretty much the same procedure form last time. The music wires were clamped on the side blocks away from the optic adapter. The clamps were screwed down using the low profile screws the Jordan obtained from UC components to allow maximum clearance for the coils (Attachment 2).

The modified side blocks with wires already clamped in them were screwed onto the adapter. We put the adapter on the EQ stops and do rough adjustments, making sure the side magnet is roughly on the center of a coil we inserted to the side. The wires were threaded through the wire clamp on the suspension block and clamped on the winches. We realigned the Oplev beam such that it is parallel to the table using the quad photodiode.

We balanced the height of the adapter. This time we used a camera facing the adapter. The tilt of the camera was set by drawing a straight line (red line in attachment 1) such that the bottom clamps on the SOS are parallel to it.

Then, we adjusted the winches such that the screws on the side blocks are on the same green line on attachment 1.

Once the height was adjusted, we clamped the wire on the suspension block and cut it at the winches.

We balanced the optic. We had to take out the front counterweight to get the balance (attachment 3).

We checked whether the wire is touching anything. We confirmed that it doesn't. The wire goes nicely through the new hole on the side blocks (attachment 4, 5).

We measure the resonance frequency for both yaw (attachment 6) and pitch (attachment 7). They both seem to be sub-Hz. The pitch trace also shows that the oscillations are centered around 0 meaning the optic is balanced.

There's still the issue of what to do with the lower back EQ stop not touching the adapter.

  16490   Mon Dec 6 14:26:52 2021 KojiUpdateVACPumping down the RGA section

Jordan reported that the RGA section needs to be pumped down to allow the analyzer to run at sufficiently low pressure (P<1e-4 torr).
The RGA section was pumped down with the TP2/TP3. The procedure is as listed below.
If the pressure go up to P>1e-4 torr, we need to keep the pump running until the scan is ready.

----
### Monitor / Control screen setup ###
1. On c1vac: cd /cvs/cds/caltech/target/c1vac/medm
2. medm -x C0VAC_MONITOR.adl&
3. RGA section (P4) 3.6e-1 torr / P3/P2 still atm.
4. medm -x C0VAC_CONTROL.adl

### TP2/TP3 backing ###
5. Turn on AUX RP with the circuit breaker hanging on the AC.
6. Open manual valve for TP2/3/ backing / PTP2/3 ~ 8torr

### TP2/TP3 starting ###
7. Turned on TP2/TP3 with the Standby OFF

### Pump down the pump spool ###
8. Connect manual RP line (Quick Connect)
9. Turned on RP1/RP3 -> quickly reached 0.4 torr
10. Open V6 for pump spool pumping -> Immediately go down to sufficiently low pressure for TP2/TP3.
(10.5 I had to close V6 at this point)
11. Open V5 to start pumping pump spool with TP3 (TP2 still stand by) -> P3 immediately goes down below 1e-4 torr. This automatically closed V6 because of the low pressure of P3 (interlocking)

### Pump down the RGA section ###
12. Open VM3 to pump down RGA section -> P4 goes down to <1e-4 torr
13. P2 is still 2e-3. So decided to open V4 to use TP2 (now it's ready) too. -> Saturated at 1.7e-3

### Shutting down ###
14. Close VM3
15. Close V4/V5 to isolate TP2/TP3
16. Stop TP2/TP3 -> Slowing down
17. Stop RP1/RP3
18. Close the manual valves for TP2/3/ backing
19. Stop AUX RP with the circuit breaker hanging on the AC.

  16491   Mon Dec 6 18:23:04 2021 YehonathanUpdateBHDSOS assembly

I installed OSEMs on the LO1 SOS. To my surprise, the side magnet is not in the center of the side OSEM. It completely misses the LED as can be seen in the attachment.

Looking at the CAD model, it turns out the position of the OSEM on the left side plate is different from the position of the OSEM on the right side plate in the SOS tower.

We need to take the optic down, swap the right and left side blocks, and resuspend it.

There is not enough 🤦🏻‍♂️in the world

  16493   Tue Dec 7 13:12:50 2021 KojiUpdateVACPumping down the RGA section

So that Jordan can run the RGA scan this afternoon, I ran TP3 and started pumping down the RGA section.

Procedure:
- Same 1~4
- Same 5
- 6 Opened only the backing path for TP3
- 7 Turned on TP3 only

- TP3 reached the nominal full speed @75kRPM

- 11 Opened V5 to pump the pump spool -> Immediately reached P3<1e-4
- 12 Opened VM3 to pump the RGA section -> Immediately reached P4<1e-4

The pumps are kept running. I'll come back later to shut down the pumps.
=> Jordan wants to heat the filament (?) and to run the scan tomorrow.
So we decided to keep TP3 running overnight. I switched TP3 to the stand-by mode (= lower rotation speed @50kRPM)

 

  16494   Wed Dec 8 10:14:43 2021 JordanUpdateVACPumping down the RGA section

After an overnight pumpdown/RGA warm up, I took a 100 amu scan of the RGA volume and subsequent pumping line. Attached is a screenshot along with the .txt file. Given the high argon peak (40) and the N2/O2 ratio, it looks like there is a decent sized air leak somehwere in the volume.

Are we interested in the hydrocarbon leak rates of this volume? That will require another scan with one of the calibrated leaks opened.

Edit: Added a Torr v AMU plot to see the partial pressures

Quote:

So that Jordan can run the RGA scan this afternoon, I ran TP3 and started pumping down the RGA section.

Procedure:
- Same 1~4
- Same 5
- 6 Opened only the backing path for TP3
- 7 Turned on TP3 only

- TP3 reached the nominal full speed @75kRPM

- 11 Opened V5 to pump the pump spool -> Immediately reached P3<1e-4
- 12 Opened VM3 to pump the RGA section -> Immediately reached P4<1e-4

The pumps are kept running. I'll come back later to shut down the pumps.
=> Jordan wants to heat the filament (?) and to run the scan tomorrow.
So we decided to keep TP3 running overnight. I switched TP3 to the stand-by mode (= lower rotation speed @50kRPM)

 

 

  16495   Thu Dec 9 00:32:56 2021 TegaUpdateCDSNew SUS medm screen update

The new SUS screen can be reached via sitemap -> IFO SUS button -> NEW ETMX dropdown menu link. Please use and provide feedback. Not sure exactly if we need/want the display screens after the IOP model on the right of the medm screen. I have not been able to locate the corresponding channels but did not want to remove them until I was sure that we don't plan to add these features to our screens. When all bugs have been ironed out, we can use appropriate macro substitution for the other optics.

The next feature to add is the BLRMS to the coil and PD channels. I plan to combine the PEM BLRMS medm implementation with the sus_single_BLRMS model block (located in  /opt/rtcds/userapps/release/cds/c1/models). This way we use the latest BLRMS block in "/opt/rtcds/userapps/release/cds/common/models/BLRMS.mdl" whilst also leveraging the previous work done on the sus_single_BLRMS model, which neatly fits into our current SUS model.

  16496   Thu Dec 9 18:22:36 2021 TegaUpdateCDSNew SUS medm screen update

Work on the medm screen for SUS RMS monitor is ongoing. The next step would be to incorporate this into the SUS medm screen, add the BLRMS model to the SUS controller model, recompile, check that the channels are being correctly addressed, then load the appropriate bandpass and lowpass filters.  

  16497   Thu Dec 9 21:57:35 2021 YehonathanUpdateBHDSOS assembly

{Yehonathan, Tega}

We took the optic out of the SOS tower and removed the side blocks. We mounted new side blocks with wires already clamped in them in the reverse order.

The Adapter was placed back into the SOS and the wires were threaded through the wire clamp and suspended on the winches. The roll of the optic was balanced using a camera (attachment 1).

The pitch was balanced. this time I used 2 counterweights instead of 1 in order to not have to take so much of the weight out.

The mechanical resonances were measured by taking a 100 sec time series of QPD readout and doing PSD estimation (attachment 2). The mirror motion was damped as much as possible before taking the measurement.

3 peaks below 1.5Hz can be seen with frequencies of 755mHz (Yaw), 942mHz, 1040mHz (Pitch + Pos). The pitch/pos peaks are a bit close to each other, I bet if we go back to 1 counterweight the situation will be better.

While inserting the side OSEM I realized I didn't check the overall height of the adapter. The magnet was too high. I will fix it tomorrow and repeat the roll balancing.

 

  16499   Fri Dec 10 15:59:23 2021 PacoUpdateBHDFinished Coil driver (even serial number) units tests

[Paco, Anchal]

We have completed modifications and testing of the HAM Coil driver D1100687 units with serial numbers listed below. The DCC tree reflects these changes and tests (Run/Acq modes transfer functions).

SERIAL # TEST result
S2100608 PASS
S2100610 PASS
S2100612 PASS
S2100614 PASS
S2100616 PASS
S2100618 PASS
S2100620 PASS
S2100622 PASS
S2100624 PASS
S2100626 PASS
S2100628 PASS
S2100630 PASS
S2100632 PASS
S2101648** FAIL (Ch1, Ch3 run mode)
S2101650** FAIL (Ch3 run mode)
S2101652** PASS
S2101654** PASS

** A fix had to be done on the DC power supply for these. The units' regulated power boards were not connected to the raw DC power, so the cabling had to be modified accordingly (see Attachment #1)

  16500   Fri Dec 10 18:55:58 2021 TegaUpdateCDSNew SUS medm screen update

Turns out the BLRMS monitoring channels for MC1, MC2, MC3, ITMY and SRM already exist in c1pem. So I modified the new SUS screen to display the BLRMS info for the aforementioned optics. Next step is to add the BLRMS monitor for PRM, ITMX, ETMX and ETMY. This would require extending the number of inputs for the "SUS" block in c1pem to accomodate the additional inputs from the remaining optics.

  16501   Fri Dec 10 19:22:01 2021 KojiUpdateVACPumping down the RGA section

The scan result was ~x10 higher than the previously reported scan on 2020/9/15 (https://nodus.ligo.caltech.edu:8081/40m/15570), which was sort of high from the reference taken on 2018/7/18.

This just could mean that the vacuum level at the RGA was x10 high.
We'll just go ahead with the vacuum repair and come back to the RGA once we return to "vacuum normal".

Meanwhile, I asked Jordan to turn off the RGA to make it cool down. I shut off RGA section and turned TP2 off.

  16503   Mon Dec 13 15:05:47 2021 TegaUpdatePEMgit repo for temp sensor and sus medm

[temperature sensor]

git repo: https://git.ligo.org/40m/tempsensor.git

todo

Update the temp sensor channels to fit with cds format, ie. "C1:PEM-TEMP_EX", "C1:PEM-TEMP_EY", "C1:PEM-TEMP_BS"

- Use FLOAT32_LE data format for the database file (/cvs/cds/caltech/target/c1pem1/tempsensor/C1PEMaux.db) to create the new channels.

- Keep the old datadase code and channels so we can compare with new temp channels afterwards. Also we need a 1-month overlap b4 deleting the old channels.

 

[sus medm screen]

git repo: https://git.ligo.org/40m/susmedmscreen.git

todo (from talk with Koji)

- Link stateword display to open "C1CDS_FE_STATUS.adl"

- Damp filter and Lock filter buttons should open a 3x1 filter screen so that the 6 filters are opened by 2 buttons compared to the old screen that has 3 buttons connected to 2X1 filter screen

- Make the LOCKIN signla modulation flow diagramlook more like the old 40m screen since that is a better layout

- Move load coefficient button to top of sus medm screen (beside stateword)

- The rectangular red outline around the oplev display is confusing and needs to be modified for clarity

- COMM tag block should not be 3D as this suggests it is a button. Make it flat and change tag name to indicate individual watchdog control as this better reflect its functionality. Rename current watchdog switch to watchdog master is it does what the 5 COMM switches do at once.

- Macro pass need to be better documented so that when we call the sus screens from locations other than sitemap, we should know what macro variables to pass in, like DCU_ID etc.

- Edit sitemap.adl to point only to the new screens. Then create a button on the new screen that points to the old screen. This way, we can still access the old screen without clogging sitemap.

- Move the new screen location to a subfolder of where the current sus screens reside, /opt/rtcds/userapps/trunk/sus/c1/medm/templates

- Rename the overview screen (SUS_CUST_HSSS_OVERVIEW.adl) to use the SUS_SINGLE nomenclature, i.e. SUS_SINGLE_OVERVIEW.adl

- Keep an eye of the cpu usage of c1pem as we add BLRMS block for other optics. 

 

 

  16504   Tue Dec 14 11:33:29 2021 TegaUpdatePEMgit repo for temp sensor and sus medm

[Temperature sensor]

Added new temp EPICs channels to database file (/cvs/cds/caltech/target/c1pem1/tempsensor/C1PEMaux.db)

Added new temp EPICs channels to slow channels ini file (/opt/rtcds/caltech/c1/chans/daq/C0EDCU.ini)

 

[SUS medm screen]

Moved new SUS screen to location : /opt/rtcds/userapps/trunk/sus/c1/medm/templates/NEW_SUS_SCREENS

Place button on the new screen to link to the old screen and replace old screens link on sitemap.

Fixed Load Coefficient button location issue

Fixed LOCKIN flow diagram issue

Fixed watchdog labelling issue

Linked STATE WORD block to FrontEnd STATUS screen

Replaced the 2x1 pit/yaw filter screens for LOCK and DAMP fliters with 3x1 LPY filter screen

*Need some more time to figure out the OPTLEV red indicator

  16505   Tue Dec 14 14:02:33 2021 YehonathanUpdateBHDSOS assembly

{Yehonathan, Paco}

I fixed the overall height of the adapter (attachment 1). I put an OSEM next to the side magnet. I positioned a camera in front of the SOS and connected it to my laptop for live streaming. I painted a line indicating the height of the OSEM plates and a line in between with the mean height. I discarded the wire clamp on the suspension block I released the wires from the winches and pulled on them until the magnet was roughly in the right position. I clamped the wires back on the winches and adjusted them until the magnet was on the middle line. I also verified that the roll of the adapter is aligned as before by making sure that the horizontal features on the adapter are parallel to the horizontal features on the SOS tower.

The wires were clamped to the suspension block using a new wire clamp.

I Found that locking the counterweight setscrew changes the alignment. Today we verified this effect. We released the setscrew and pre-compensated by adjusting the counterweight such that when the setscrew was locked the mirror was aligned.

We measured mechanical resonances (attachment 2). This time the yaw motion was very quiet so we got a smaller peak for the yaw. The peaks are the same as before. Y readout has peaks around the pitch and pos resonances that don't appear in the X readout. I'm not sure what they are. Maybe coming from the QPD electronics.

We locked the adapter using the EQ stops. We made sure the alignment stays close to ideal.

We installed OSEMs on the SOS. We chose suboptimal OSEMs because LO1 will only be used for steering. I made a spreadsheet copying the OSEM catalog into it. There we mark which OSEM goes where.

I cleaned the optic using the ion gun with a pressure of 30 PSI.

The next steps are:

1. Engrave the SOS tower.

2. Cut the wire at the winches and remove the winch adapter plate.

3. Wrap the SOS with foil.

4. Install the SOS in the vacuum chamber.

 

 

  16506   Tue Dec 14 19:29:42 2021 PacoUpdateBHD1Y0 rack work for LO1

[Paco]

Two coil drivers have been installed on 1Y0 (slots 6, 7, for LO1 SOS). All connections have been made from the DAC, AI board, DAC adapter, Coil driver, Sat Amp box. Then no SOS load installed, all return connections have been made from Sat Amp box, ADC adapter, AA board, and to ADC. We will continue this work tomorrow, and try to test everything before closing the loop for LO1 suspension.

  16507   Wed Dec 15 13:57:59 2021 PacoUpdateComputersupgraded ubuntu on zita

[Paco]

Upgraded zita's ubuntu and restarted the striptool script.

  16508   Wed Dec 15 15:06:08 2021 JordanUpdateVACVacuum Feedthru Install

Jordan, Chub

We installed the 4x DB25 feedthru flange on the North-West port of ITMX chamber this afternoon. It is ready to go.

  16511   Wed Dec 15 22:09:53 2021 YehonathanUpdateBHDSOS assembly

{Paco, Yehonathan, Anchal}

I cut the wires from the winches and removed the winch adapter plate. I engrave  'LO1' on the SOS tower. Me and Paco wrapped the SOS with foil and transported it to Anchal who put it inside the ITMX chamber.

The transportation seems to be successful. Nothing broke. However, we found that even with the short side OSEM the LO1, as it is now, cannot sit in its designed position since ITMX's side OSEM stands in its way.

If there are magnets on both ITMX sides we can move its side OSEM to the other side. Another option is to resuspend LO1 with a side magnet on its left side.

 

  16512   Thu Dec 16 12:21:16 2021 AnchalUpdateBHDCoil driver test failed for S2100619-v1

Today I found one of the coil driver boards, S2100619 failed the test on CH2. There appears to be an extra phase lag after 10 kHz and some resonant-like feature at 7 kHz. This of course is very high-frequency stuff and maybe we don't care about these deviations. But it could mean something is off with the channel and could potentially lead to failure in the relevant frequency band in the future. I'll need help to debug this. Please see the attachment for details of test failure.

  16513   Thu Dec 16 15:04:12 2021 ChubUpdateElectronicsITMX feedthroughs and in-vac cables installed

The ITMX 10" flange with four DSUB-25 feedthroughs has been install with the cables connected at the in-vac side.  See photo; as requested, LO1-1 and LO1-2 are connected to the top row of feedthroughs from left to right respectively and the opposite ends of the cables placed left to right on the laser table.  PR2-1 and PR2-2 are connected to the lower row of feedthroughs from left to right respectively, with the opposite ends placed on the surface below the laser from left to right.  This seemed the easiest way to keep the cable orientation clear.

  16514   Thu Dec 16 15:32:59 2021 AnchalUpdateBHDFinished Coil driver (odd serial number) units tests

We have completed modifications and testing of the HAM Coil driver D1100687 units with serial numbers listed below. The DCC tree reflects these changes and tests (Run/Acq modes transfer functions).

SERIAL # TEST result
S2100609 PASS
S2100611 PASS
S2100613 PASS
S2100615 PASS
S2100617 PASS
S2100619 FAIL (CH2 phase)
S2100621 PASS
S2100623 PASS
S2100625 PASS
S2100627 PASS
S2100629 PASS
S2100631 PASS
S2100633 Waiting for more components
S2101649** PASS
S2101651** PASS
S2101653** PASS
S2101655** PASS

** A fix had to be done on the DC power supply for these. The units' regulated power boards were not connected to the raw DC power, so the cabling had to be modified accordingly.

Further, Paco fixed the two even serial number units (S2101648, S211650) that failed the test. The issues were minor soldering mistakes that were easily resolved.

  16515   Thu Dec 16 15:54:08 2021 KojiUpdateElectronicsITMX feedthroughs and in-vac cables installed

Thanks for the installation.

With regard to the connector convention, let's use the attached arrangement so that it will be consistent with the existing flange DSUB configuration. Not a big deal.

 

  16516   Thu Dec 16 17:41:12 2021 KojiUpdateBHDCoil driver test failed for S2100619-v1

Good catch. It turned out that the both + and - side of the output stages for CH2 were oscillating at ~600kHz. If I use a capacitance sticks to touch arbitrarily around the components, it stops their oscillation and they stay calm.
It means that the phase margin becomes small while the circuit starts up.

I decided to increase the capacitances C6 and C20 (WIMA 150pF) to 330pF (WIMA FPK2 100V) and the oscillation was tamed. 220pF didn't stop them. After visually checked the signal behavior with an oscilloscope, the unit was passed to Anchal for the TF test.

The modification was also recorded in the DCC S2100619

  16517   Thu Dec 16 17:57:17 2021 AnchalUpdateBHDFinished Coil driver (odd serial number) units tests

S2100619 was fixed by Koji and it passed the test after that.

Quote:
SERIAL #  
S2100619 FAIL (CH2 phase)

 

  16518   Thu Dec 16 18:16:36 2021 YehonathanUpdateBHDSOS assembly

Today I glued magnets onto the new 3/4" mirror adapters. I also took the opportunity to make some more side magnets assemblies.

Yesterday I mounted PR3/SR2 3/4" thick mirror onto one of the new adapter. There seem to be no issues for now.

I started the process of suspending AS1 (E2000226-A). The Lambda Optic mirror with the closest specs has Rc = 2 m. I attached side blocks with clamped wires onto adapter number 7 - side block with a magnet on the right.

I then took one of the Lambda Optic mirrors and tried mounting it in the adapter. It was quite difficult to get it right. Unfortunately, I chipped the edge of the substrate (attachment 1) 🤦🏻‍♂️. I put the mirror back in the box and decided to use the spare mirror. I successfully mounted it into the adapter but when I put the clamping screws one of them fell on the mirror 🤦🏻‍♂️🤦🏻‍♂️. There is no visible damage though. I took some pictures (attachment 2-4).

I and Anchal then started suspending the mirror but then we found that one of the wires is dented in the middle 🤦🏻‍♂️🤦🏻‍♂️🤦🏻‍♂️. I'm burned out for today.

Late update: one nice thing that I found yesterday is that the glue is viscous enough to hold the dumbells without a metal sheet from above holding the magnets. This greatly simplifies the gluing process.

 

  16519   Fri Dec 17 12:32:35 2021 KojiUpdateSUSRemaining task for 2021

Anything else? Feel free to edit this entry.

- SUS: AS1 hanging

- SUS: PR3/SR2/LO2 3/4" thick optic hanging

v Electronics chain check (From DAC to the end of the in-air cable / From the end of the in-air cable to the ADC)
[ELOG 16522]

- Long cable installation (4x 70ft)

- In-air cable connection to the flange

- In-vac wiring (connecting LO1 OSEMs)

- LO1 OSEM insertion/alignment

- LO1 Damping test

 

  16520   Fri Dec 17 17:50:17 2021 YehonathanUpdateBHDSOS assembly

I threaded a new wire through a different side block with a magnet and clamped it under a microscope. It was hard, but eventually, I was able to do it by holding the wire on both sides of the side block with weights.

The dented wire was discarded and the side block that was mounted on the AS1 adapter was put aside. I mounted the side block with the new wire on the AS1 adapter.

 

Anchal and I hanged the AS1 adapter and clamped the wires on the winches of an SOS tower. I balanced the roll and adjusted the height of the magnet with respect to a side OSEM using a camera (attachments 1 & 2).

I shoot the Hene laser on the optic and look at the reflection. I align the laser beam to be as close as possible to the center of the mirror. The OpLev needs to be realigned.

To my surprise, the ghost beam shoots up above the reflected beam! See attachment 3. I check to see that the arrow which marks the thinnest side of the mirror is horizontal (attachment 4). WTF?!

Also, now I realize that the marking on the Lambda optics are pencil markings 😵😵😵.

ELOG V3.1.3-