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ID Date Author Typedown Category Subject
  14216   Tue Sep 25 18:08:50 2018 yukiConfigurationASCY end table upgrade plan

[ Yuki, Gautam ]

We want to remotely control steeing PZT mirrors so its driver is needed. We already have a PZT driver board (D980323-C) and the output voltage is expected to be verified to be in the range 0-100 V DC for input voltages in the range -10 to 10 V DC.
Then I checked to make sure ir perform as we expected. The input signal was supplied using voltage calibrator and the output was monitored using a multimeter. 
But it didn't perform well. Some tuning of voltage bias seemed to be needed. I will calculate its transfer function by simulation and check the performance again tommorow. And I found one solder was off so it needs fixing.  

Reference:
diagram --> elog 8932
 

Plan of Action:

  • Check PZT driver performs as we expected
  • Also check cable, high voltage, PZT mirrors, anti-imaging board
  • Obtain calibration factor of PZT mirrors using QPD
  • Measure some status value before changing setup (such as tranmitted power of green laser)
  • Revise setup after a new lens arrives
  • Align the setup and check mode-matching
  • Measure status value again and confirm it improves
  • (write programming code of making alignment control automatically)
  14218   Thu Sep 27 14:02:55 2018 yukiConfigurationASCPZT driver board verification

[ Yuki, Gautam ]

I fixed the input terminal that had been off, and made sure PZT driver board performs as we expect. 

At first I ran a simulation of the PZT driver circuit using LTspice (Attached #1 and #2). It shows that when the bias is 30V the driver performs well only with high input volatage (bigger than 3V). Then I measured the performance as following way:

  1. Applied +-15V to the board with an expansion card and 31.8V to the high voltage port which is the maximum voltage of PS280 DC power supplier C10013.
  2. Terminated input and connectd input bias to GND, then set offset to -10.4V. This value is refered as elog:40m/8832.
  3. Injected DC signal into input port using a function generator.
  4. Measured voltage at the OUT port and MON port.

The result of this is attached #3 and #4. It is consistent with simulated one. All ports performed well.

  • V(M1_PIT_OUT) = -4.86 *Vin +49.3 [V]
  • V(M1_YAW_OUT) = -4.86 *Vin +49.2 [V]
  • V(M2_PIT_OUT) = -4.85 *Vin +49.4 [V]
  • V(M2_YAW_OUT) = -4.86 *Vin +49.1 [V]
  • V(M1_PIT_MON) = -0.333 *Vin +3.40 [V]
  • V(M1_YAW_MON) = -0.333 *Vin +3.40 [V]
  • V(M2_PIT_MON) = -0.333 *Vin +3.40 [V]
  • V(M2_YAW_MON) = -0.333 *Vin +3.40 [V]

The high voltage points (100V DC) remain to be tested.

Attachment 1: PZTdriverSimulationDiagram.pdf
PZTdriverSimulationDiagram.pdf
Attachment 2: PZTdriverSimulationResult.pdf
PZTdriverSimulationResult.pdf
Attachment 3: PZTdriverPerformanceCheck_ResultOUT.pdf
PZTdriverPerformanceCheck_ResultOUT.pdf
Attachment 4: PZTdriverPerformanceCheck_ResultMON.pdf
PZTdriverPerformanceCheck_ResultMON.pdf
Attachment 5: PZTdriver.asc
Version 4
SHEET 1 2120 2120
WIRE 1408 656 1408 624
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WIRE 1712 656 1712 624
WIRE 1872 656 1872 624
WIRE 2016 656 2016 624
WIRE 1408 768 1408 736
WIRE 1552 768 1552 736
WIRE 1712 768 1712 736
... 193 more lines ...
  14219   Sun Sep 30 20:14:51 2018 yukiConfigurationASCQPD calibration

[ Yuki, Gautam, Steve ]

Results:
I calibrated a QPD (D1600079, V1009) and made sure it performes well. The calibration constants are as follows:

X-Axis: 584 mV/mm
Y-Axis: 588 mV/mm

Details:
The calibration of QPD is needed to calibrate steeing PZT mirrors. It was measured by moving QPD on a translation stage. The QPD was connected to its amplifier (D1700110-v1) and +-18V was supplied from DC power supplier. The amplifier has three output ports; Pitch, Yaw, and Sum. I did the calibration as follows:

  • Center beam spot on QPD using steering mirror, which was confirmed by monitored Pitch and Yaw signals that were around zero.  
  • Kept Y-axis micrometer fixed, moved X-axis micrometer and measured the outputs. 
  • Repeated the procedure for the Y-axis. 

The results are attached. The main signal was fitted with error function and I drawed a slope at zero crossing point, which is calibration factor. I determined the linear range of the QPD to be when the output was in range -50V to 50V, then corresponding displacement range is about 0.2 mm width. Using this result, the PZT mirrors will be calibrated in linear range of the QPD tomorrow. 

Comments:

  • Some X-Y coupling existed. When one axis micrometer was moved, a little signal of the other direction was also generated.
  • As Gautam proposed in the previous study, there is some hysteresis. That process would bring some errors to this result.
  • A scale of micrometer is expressed in INCH!
  • The micrometer I used was made to have 1/2 inch range, but it didn't work well and the range of X-axis was much narrower. 

Reference:
previous experiment by Gautam for X-arm: elog:40m/8873, elog:40m/8884

Attachment 1: QPDcalibrationXaxis.pdf
QPDcalibrationXaxis.pdf
Attachment 2: QPDcalibrationYaxis.pdf
QPDcalibrationYaxis.pdf
  14220   Mon Oct 1 12:03:41 2018 not yukiConfigurationASCPZT driver board verification

I assume this QPD set is a D1600079/D1600273 combo.

How much was the SUM output during the measurement? Also how much were the beam radii of this beam (from the error func fittings)?
Then the calibration [V/m] is going to be the linear/inv-linear function of the incident power and the beam radus.

You mean the linear range is +/-50mV (for a given beam), I guess.

 

  14221   Mon Oct 1 13:33:55 2018 yukiConfigurationASCQPD calibration
Quote:

I assume this QPD set is a D1600079/D1600273 combo.

How much was the SUM output during the measurement? Also how much were the beam radii of this beam (from the error func fittings)?
Then the calibration [V/m] is going to be the linear/inv-linear function of the incident power and the beam radus.

You mean the linear range is +/-50mV (for a given beam), I guess.

  • The SUM output was from -174 to -127 mV.
  • The beam radii calculated from the error func fittings was 0.47 mm.
  • Total optical path length measured by a ruler= 36 cm.
  • Beam power measured at QPD was 2.96 mW. (There are some loss mechanism in the setup.)

Then the calibration factor of the QPD is

X axis: 584 * (POWER / 2.96mW) * (0.472mm /  RADIUS) [mV/mm]
Y axis: 588 * (POWER / 2.96mW) * (0.472mm /  RADIUS) [mV/mm].

Attachment 1: Pic_QPDcalibration.jpg
Pic_QPDcalibration.jpg
  14222   Mon Oct 1 20:39:09 2018 gautamConfigurationASCc1asy

We need to set up a copy of the c1asx model (which currently runs on c1iscex), to be named c1asy, on c1iscey for the green steering PZTs. The plan discussed at the meeting last Wednesday was to rename the existing model c1tst into c1asy, and recompile it with the relevant parts copied over from c1asx. However, I suspect this will create some problems related to the "dcuid" field in the CDS params block (I ran into this issue when I tried to use the dcuid for an old model which no longer exists, called c1imc, for the c1omc model).

From what I can gather, we should be able to circumvent this problem by deleting the .par file corresponding to the c1tst model living at /opt/rtcds/caltech/c1/target/gds/param/, and rename the model to c1asy, and recompile it. But I thought I should post this here checking if anyone knows of other potential conflicts that will need to be managed before I start poking around and breaking things. Alternatively, there are plenty of cores available on c1iscey, so we could just set up a fresh c1asy model...

 
  • (write programming code of making alignment control automatically)
  14224   Tue Oct 2 18:50:53 2018 yukiConfigurationASCPZT mirror calibration

[ Yuki, Gautam ]

I calibrated PZT mirrors. The ROUGH result was attached. (Note that some errors and trivial couplings coming from inclination of QPD were not considered here. This should be revised and posted again.) 

The PZT mirrors I calibrated were:

  • A 2-inch CVI mirror (45 degree, HR and AR for 532nm)
  • A 1-inch Laseroptik mirror (45 degree, HR and AR for 532nm)

I did the calibration as follows:

  • +-15V was supplied to PZT driver circuit, +100V to PZT driver bias, and +-18V to QPD amplifier.
  • Optical path length was set to be same as that when I calibrated QPD, which is 36cm.
  • The full range of CVI mirror is 3.5mrad according to its datasheet and linear range of QPD is 0.2mm, so I set the distance between PZT mirrors and QPD to be about 6cm. (I realized it was wrong. When mirror tilts 1 deg, the angle of beam changes 2 deg. So the distance should be the half.)
  • After applying 0V to PZT driver input (at that time 50V was applied to PZT mirror), then centered beam spot on QPD using steering mirror, which was confirmed by monitored Pitch and Yaw signals of QPD that were around zero.  
  • In order to avoid hysteresis effect, I stared with an input signal of -10V. I then increased the input voltage in steps of 1V through the full range from -10V to +10V DC. The other input was kept 0V.
  • Both the X and Y coordinates were noted in the plot in order to investigate pitch-yaw coupling.

The calibration factor was

CVI-pitch: 0.089 mrad/V

CVI-yaw: 0.096 mrad/V

Laseroptic-pitch: 0.062 mrad/V

Laseroptic-yaw: 0.070 mrad/V

Comments:

  • I made sure that PZT mirrors move linearly in full input range (+-10V).
  • PZT CH1 input: Yaw, CH2: Pitch, CH3: +100V bias
  • The calibration factor of PZT mirrors [mrad/V] are not consistent with previous calibration (elog:40m/8967). I will check it again.
  • I measured the beam power in order to calibrate QPD responce with a powermeter, but it didn't have high precision. So I used SUM output of QPD to the calibration.
  • Full range of PZT mirrors looks 2 times smaller.

Reference:
Previous calibration of the same mirrors, elog:40/8967

Attachment 1: PZTM1calibrationCH2.pdf
PZTM1calibrationCH2.pdf
Attachment 2: PZTM1calibrationCH1.pdf
PZTM1calibrationCH1.pdf
Attachment 3: PZTM2calibrationCH2.pdf
PZTM2calibrationCH2.pdf
Attachment 4: PZTM2calibrationCH1.pdf
PZTM2calibrationCH1.pdf
  14226   Wed Oct 3 14:24:40 2018 yukiConfigurationASCY end table upgrade plan

Interim Procedure Report:

Purpose

The current setup of AUX Y-arm Green locking has to be improved because:

  • current efficiency of mode matching is about 50%
  • current setup doesn't separate the degrees of freedom of TEM01 with PZT mirrors (the difference of gouy phase between PZT mirrors should be around 90 deg) 
  • we want to remotely control PZT mirrors for alignment

What to do

  • Design the new setup and order optices needed (finished!)
      - As the new setup I designed, adding a new lens and slightly changing the position of optics are only needed. The new lens was arrived here.
  • Check electronics (PZT, PZT driver, high voltage, cable, anti-imaging board) (finished!)
      
    - All electronics were made sure performing well.
      - The left thing to do is making a cable. (Today's tasks)
  • Calibrate PZT mirror [mrad/V] (finished!)
      
    - The result was posted here --> elog:40m/14224.
  • Measure the status value of the current setup (power of transmitted light ...etc) (Tomorrow, --> finished!)
  • Install them in the Y-end table and align the beam (Will start from Tomorrow) (The setup has a probrem I found on 10/04)
  • Measure the status value of the new setup
      - I want to finish above during my stay.
  • Prepare the code of making alignment automaticaly
  14227   Wed Oct 3 18:15:34 2018 yukiConfigurationASCAI board improvement

[ Yuki, Gautam ]

I improved Anti-Imaging board (D000186-Rev.D), which will be put between DAC port and PZT driver board.

It had notches at f = 16.6 kHz and 32.7 kHz, you can see them in the plot attached. So I replaced some resistors as follows:

  • R6 and R7 replaced with 511 ohm (1206 thin film resistor)
  • R8 replaced with 255 ohm (1206 thin film resistor)
  • R14 and R15 replaced with 549 ohm (1206 thin film resistor)
  • R16 replaced with 274 ohm (1206 thin film resistor)

Then the notch moved to 65.9 kHz (> sampling frequency of DAC = 64 kHz, good!). 
(The plot enlarged around the notch frequency and the plot of all channels will be posted later.)

All electronics and optics seem to be ready. 

Reference, elog:40m/8857
Diagram, D000186-D.pdf

Attachment 1: TF_AIboard.pdf
TF_AIboard.pdf
  14228   Thu Oct 4 00:44:50 2018 yukiConfigurationASCAI board improvement

[ Yuki, Gautam ]

I made a cable which connects DAC port (40 pins) and AI board (25 pins). I will check if it works.

Tomorrow I will change setup for improvement of AUX Y-end green locking. Any optics for IR will not be moved in my design, so this work doesn't affect Y-arm locking with main beam. 
While doing this work, I will do:

  • check if the cable works
  • make another cable which connects AI board (10 pins) and PZT driver (10 pins).
  • check if eurocate in Y-rack (IY4?) applies +/-5V, +/-15V and +/-24V. It will be done using an expansion card.
  • improve alignment servo for X-end.
  • setup alignment servo for Y-end.
  • about optical loss measurement.  
  14230   Thu Oct 4 22:15:30 2018 yukiConfigurationASCY-end table upgrade

Before changing setup at Y-end table, I measured the status value of the former setup as follows. These values will be compared to those of upgraded setup.

  • beam power going into doubling crystal (red12): 20.9 mW with filter, 1064nm
  • beam power going out from doubling crystal (red12): 26.7 mW with filter, 532nm
  • beam power going into faraday isolator (green5): 0.58 mW without filter, 532nm
  • beam power going out from faraday isolator (green5): 0.54 mW without filter, 532nm
  • beam power going to ETMY: 0.37 mW without filter, 532nm
  • beam power of transmitted green light of Y-arm, which was measured by C1:ALS-TRY_OUT: 0.5 (see attachment #1)

(These numbers are shown in the attachment #2.)

The setup I designed is here. It can bring 100% mode-matching and good separation of degrees of TEM01, however I found a probrem. The picture of setup is attached #3. You can see the reflection angle at Y7 and Y8 is not appropriate. I will consider the schematic again.

Attachment 1: AUXYGreenLock20180921.jpg
AUXYGreenLock20180921.jpg
Attachment 2: Pic_FormerSetup.jpeg
Pic_FormerSetup.jpeg
Attachment 3: Pic_CurrentSetup1004.jpg
Pic_CurrentSetup1004.jpg
  14231   Fri Oct 5 00:46:17 2018 KojiConfigurationASCY-end table upgrade

???

The SHG crystal has the conversion efficiency of ~2%W (i.e. if you have 1W input @1064, you get 2% conversion efficiency ->20mW@532nm)

It is not possible to produce 0.58mW@532nm from 20.9mW@1064nm because this is already 2.8% efficiency.

 

  14232   Fri Oct 5 17:32:38 2018 yukiConfigurationASCY-end table upgrade

I measured it with the wrong setting of a powermeter. The correct ones are here:

  • beam power going into doubling crystal (red12): 240 mW, 1064nm
  • beam power transmitted dichroic mirror (Y5): 0.70 mW, 532nm
  • beam power going into faraday isolator (green5): 0.58 mW, 532nm
  • beam power going out from faraday isolator (green5): 0.54 mW, 532nm
  • beam power going to ETMY: 0.37 mW, 532nm
  • beam power of transmitted green light of Y-arm, which was measured by C1:ALS-TRY_OUT: 0.5 (see attachment #1)

The calculated conversion efficiency of SHG crystal is 1.2%W.

  14233   Fri Oct 5 17:47:55 2018 gautamConfigurationASCY-end table upgrade

What about just copying the Xend layout? I think it has good MM (per calculations), reasonable (in)sensitivity to component positions, good Gouy phase separation, and I think it is good to have the same layout at both ends. Since the green waist has the same size and location in the doubling crystal, it should be possible to adapt the X end solution to the Yend table pretty easily I think.

Quote:

The setup I designed is here. It can bring 100% mode-matching and good separation of degrees of TEM01, however I found a probrem. The picture of setup is attached #3. You can see the reflection angle at Y7 and Y8 is not appropriate. I will consider the schematic again.

  14234   Fri Oct 5 22:49:22 2018 yukiConfigurationASCY-end table upgrade

I designed a new layout. It has good mode-matching efficiency, reasonable sensitivity to component positions, good Gouy phase separation. I'm setting optics in the Y-end table. The layout will be optimized again after finishing (rough) installation.  (The picture will be posted later)

  14235   Sun Oct 7 16:51:03 2018 gautamConfigurationLSCYarm triggering changed

To facilitate Yuki's alignment of the EY green beam into the Yarm cavity, I have changed the LSC triggering and PowNorm settings to use only the reflected light from the cavity to do the locking of Arm Cavity length to PSL. Running the configure script should restore the usual TRY triggering settings. Also, the X arm optics were macroscopically misaligned in order to be able to lock in this configuration.

  14236   Sun Oct 7 22:30:42 2018 yukiConfigurationLSCYarm Green locking was recovered

I finished installation of optics in the Y-end and recovered green locking. Current ALS-TRY_OUTPUT is about 0.25, which is lower than before. So I still continue the alignment of the beam. The simulation code was attached. (Sorry. The optic shown as QWP2 is NOT QWP. It's HWP.)

Attachment 1: Pic_NewLayout1007.jpg
Pic_NewLayout1007.jpg
Attachment 2: YendGreenModeMatching.zip
  14237   Mon Oct 8 00:46:35 2018 yukiConfigurationASCY-end table upgrade
Quote:

I measured it with the wrong setting of a powermeter. The correct ones are here:

  • beam power going into doubling crystal (red12): 240 mW, 1064nm
  • beam power transmitted dichroic mirror (Y5): 0.70 mW, 532nm
  • beam power going into faraday isolator (green5): 0.58 mW, 532nm
  • beam power going out from faraday isolator (green5): 0.54 mW, 532nm
  • beam power going to ETMY: 0.37 mW, 532nm
  • beam power of transmitted green light of Y-arm, which was measured by C1:ALS-TRY_OUT: 0.5 (see attachment #1)

After installation I measured these power again.

  • beam power going into doubling crystal: 241 mW, 1064nm
  • beam power transmitted dichroic mirror: 0.70 mW, 532nm
  • beam power going into faraday isolator: 0.56 mW, 532nm
  • beam power going out from faraday isolator: 0.53 mW, 532nm
  • beam power going to ETMY: 0.36 mW, 532nm

There is a little power loss. That may be because of adding one lens in the beam path. I think it is allowable margin.

  14238   Mon Oct 8 18:56:52 2018 gautamConfigurationASCc1asx filter coefficient file missing

While pointing Yuki to the c1asx servo system, I noticed that the filter file for c1asx is missing in the usual chans directory. Why? Backups for it exist in the filter_archive subdirectory. But there is no current file. Clearly this doesn't seems to affect the realtime code execution as the ASX model seems to run just fine. I copied the latest backup version from the archive area into the chans directory for now.

  14239   Tue Oct 9 16:05:29 2018 gautamConfigurationASCc1tst deleted, c1asy deployed.

Setting up c1asy:

  • Backed up old c1tst.mdl as c1tst_old_bak.mdl in /opt/rtcds/userapps/release/cds/c1/models
  • Copied the c1tst model to /opt/rtcds/userapps/release/isc/c1/models/c1asy.mdl as this is where the c1asx.mdl file resides.
  • Backed up original c1rfm.mdl as c1rfm_old.mdl in /opt/rtcds/userapps/release/cds/c1/models (since the old c1tst had an RFM block which is unnecessary).
  • Deleted offending RFM block from c1rfm.mdl.
  • Recompiled and re-installed c1rfm.mdl. Model has not yet been restarted, as I'd like suspension watchdogs to be shutdown, but c1susaux EPICS channels are presently not responsive.
  • Removed c1tst model (C-node91) from /opt/rtcds/caltech/c1/target/gds/param/testpoints.
  • Removed /opt/rtcds/caltech/c1/target/gds/param/tpchn_c1tst.par (at this point, DCUID 91 is free for use by c1asy).
  • Moved c1tst line in /opt/rtcds/caltech/c1/target/daqd/master to "old model definitions models" section.
  • Added /opt/rtcds/caltech/c1/target/gds/param/tpchn_c1asy.par to the master file.
  • Edited/diskless/root.jessie/etc/rtsystab to allow c1asy to be run on c1iscey.
  • Finally, I followed the instructions here to get the channels into frames and make all the indicators green.

Now Yuki can work on copying the simulink model (copy c1asx structure) and implementing the autoalignment servo.

Attachment 1: CDSoverview_ASY.png
CDSoverview_ASY.png
  14240   Tue Oct 9 23:03:43 2018 yukiConfigurationLSCYarm Green locking was recovered

[ Yuki, Gautam, Steve ]

To align the green beam in Y-end these hardware were installed:

  • PZT mirrors in Y-end table
  • PZT driver in 1Y4 rack
  • Anti-Imaging board in 1Y4 rack
  • cables (DAC - AIboard - PZTdriver - PZT)
  • high voltage supplier 

I made sure that DAC CH9~16 and cable to AI-board worked correctly. 

When we applied +100V to PZT driver and connected DAC, AI-board and PZT drive, the output voltage of the driver was not correct. I'll check it tomorrow.

Attachment 1: Pic_1Y4.jpg
Pic_1Y4.jpg
Attachment 2: Pic_PZTcable.jpg
Pic_PZTcable.jpg
  14241   Wed Oct 10 12:38:27 2018 yukiConfigurationLSCAll hardware was installed

I connected DAC - AIboard - PZTdriver - PZT mirrors and made sure the PZT mirrors were moving when changing the signal from DAC. Tomorrow I will prepare alignment servo with green beam for Y-arm.

  14257   Mon Oct 15 20:11:56 2018 yukiConfigurationASCY end table upgrade plan

Final Procedure Report for Green Locking in YARM:

Purpose

The current setup of AUX Y-arm Green locking has to be improved because:

  • current efficiency of mode matching is about 50%
  • current setup doesn't separate the degrees of freedom of TEM01 with PZT mirrors (the difference of gouy phase between PZT mirrors should be around 90 deg) 
  • we want to remotely control PZT mirrors for alignment

What to do

  • Design the new setup and order optices needed (finished!)
      - As the new setup I designed, adding a new lens and slightly changing the position of optics are only needed. The new lens was arrived here.
  • Check electronics (PZT, PZT driver, high voltage, cable, anti-imaging board) (finished!)
      
    - All electronics were made sure performing well.
      - The left thing to do is making a cable. (Today's tasks)
  • Calibrate PZT mirror [mrad/V] (finished!)
      
    - The result was posted here --> elog:40m/14224.
  • Measure the status value of the current setup (power of transmitted light ...etc) (finished!)
  • Install them in the Y-end table and align the beam (Almost finished!) (GTRY signal is 0.3 which means Mode-Matching efficiency is about 30%. It should be improved.)
  • Measure the status value of the new setup (finished!)
  • Prepare the code of making alignment automaticaly
    • see sitemap.adl>ASC>c1asy. I prepared medm. If you move PZT SLIDERS then you can see the green beam also moves.
    • Preparing filters is needed. You can copy them from C1ASX.
    • Note that now you cannot use C1ASX servo because filters are not applied.
  14260   Wed Oct 17 20:46:24 2018 yukiConfigurationASCY end table upgrade plan

To do for Green Locking in YARM:

The auto-alignment servo should be completed. This servo requires many parameters to be optimized: demodulation frequency, demodulation phase, servo gain (for each M1/2 PIT/YAW), and matrix elements which can remove PIT-YAW coupling. 

  14301   Fri Nov 16 15:09:31 2018 SteveConfigurationVACnot venting cryo and ion pumps

Notes on the ion pumps and cryo pump:

  • Our 4 ion pumps were closed off for a lomg time. I estmated their pressure to be around ~1 Torr. After talking with Koji we decided not to vent them.

  • It'd be still useful to wire their position sensors. But make sure we do not actuate the valves. 

  • The cryo pump was regenerated to 1e-4 Torr about 2 years ago. It's pressure can be ~ 2 Torr with charcoal powder. It is a dirty system at room temperature.

  • Do not actuate VC1 and VC2, and keep its manual valve closed.

  • IF someone feels we should vent them for some reason, let us know here in the elog before Monday morning.

 

Quote:

Wiring of the power, Ethernet, and indicator lights for the vacuum Acromag chassis is complete. Even though this crate will only use +24V DC, I wired the +/-15V connector and indicator lights as well to conform to the LIGO standard. There was no wiring diagram available, so I had to reverse-engineer the wiring from the partially complete c1susaux crate. Attached is a diagram for future use. The crate is ready to begin software developing on Monday. 

 

  14322   Tue Nov 27 17:06:51 2018 SteveConfigurationVACAgilent 84FS turbo installed as TP2

Chub & Steve,

We swapped in our  replacement of Varian V70D "bear-can" turbo as factory clean.

The new Agilent TwisTorr 84 FS  turbo pump [ model x3502-64002,  sn IT17346059 ]  with intake screen, fan, vent valve. The controller  [ model 3508-64001, sn IT1737C383 ] and a larger drypump IDP-7,  [ model x3807-64010, sn MY17170019 ] was installed.

Next things to do:

  1. implement hardware interlock to close V4 at 80% pumping speed slowdown of "standby" rotation speed, estimated to be ~ 40,000 RPM ( when Standby 50K RPM  )
  2. set up isolation valve in the foreline of TP2, with delayed start of the IDP-7 and/or use relay to power drypump.  This turbo controller can not switch off or start of the dry pump. [ Agilent isolation valve #X3202-60055, with position indicator, pneumatic actuation, 115V solenoid ]..........as a second thought, we do not need isolation valve if we go with the relay option. The IDP-7 has built in delay of 10-15 sec
  3. test performance of new turbo
  14382   Thu Jan 3 21:17:49 2019 ranaConfigurationComputersWorkstation Upgrade: Donatella -> Scientific Linux 7.2

donatella was one of our last workstations running ubuntu12. we installed SL7 on there today

  1. had to use a DVD; wouldn't boot from USB stick
  2. made sure to use userID=1001 and groupID=1001 at the initial install part
  3. went to the Keith Thorne LLO wiki on SL7
  4. The 'yum update' command failed due to a gstreamer conflict. I did "yum remove gstreamer1-plugins-ugly-free-1.10.4-3.el7.x86_64" and then it continued a bit more.
  5. Then there are ~20 errors related to gds-crtools that look like this:Error: Package: gds-crtools-2.18.12-1.el7.x86_64 (lscsoft-production) Requires: libMatrix.so.6.14()(64bit)

  6. I re-ran the yum install .... command using the --skip-broken command and that seemed to complete, although I guess the GDS stuff will not work.
  7. Installed: terminator, inconsolata-fonts, 
  8. Installed XFCE desktop as per K Thorne:  yum groupinstall "Xfce" -y
  9.  
Attachment 1: IMG_20190103_205158.jpg
IMG_20190103_205158.jpg
  14387   Mon Jan 7 11:54:12 2019 JonConfigurationComputer Scripts / ProgramsVac system shutdown

I'm making a controlled shutdown of the vac controls to add new ADC channels. Will advise when it's back up.

  14388   Mon Jan 7 19:21:45 2019 JonConfigurationComputer Scripts / ProgramsVac system shutdown

ADC work finished for the day. The vac controls are back up, with all valves CLOSED and all pumps OFF.

Quote:

I'm making a controlled shutdown of the vac controls to add new ADC channels. Will advise when it's back up.

 

  14476   Fri Mar 8 08:40:26 2019 AnjaliConfiguration Frequency stabilization of 1 micron source

The schematic of the homodyne configuration is shown below.

Following are the list of components

Item Quantity Availability Part number  Remarks
Laser (NPRO) 1 Yes    
Couplers (50/50) 5 3 No's FOSC-2-64-50-L-1-H64F-2 Fiber type : Hi1060 Flex fiber
Delay fiber  two loops of 80 m Yes PM 980

 

One set of fiber is now kept along the arm of the interferometer

InGaAs PD (BW > 100 MHz) 4 Yes NF1611

Fiber coupled (3 No's)

Free space ( 2 No's)

SR560 3 Yes    
  • The fiber mismatch between the couplers and the delay fiber could affect the coupling efficiency
Attachment 1: Homodyne_setup.png
Homodyne_setup.png
  14664   Tue Jun 11 19:25:58 2019 aaronConfigurationBHDReviving the single OMC BHD design?

I drew out some idea of how we might use a single OMC to clean both paths of the BHD after mixing, without being susceptible to polarization-dependent effects within the OMC. Basically, can we send the two legs of the BHD into the OMC counterpropagating. I've attached a diagram.

I think one issue would be scattered light, since any backscatter directly couples into the counterpropagating mode, and thus directly to the PD. However, unless the polarization of the scattered light rotates it would not scatter back to the IFO. And, since the LO and signal mix before the OMC, this scattered light would not directly add phase noise.

Maybe more problematic would be that if the rejection at the PBS (or the polarization rotation) isn't perfect, light from the LO directly couples into the dark port. Can we get away with a Faraday isolator before the OMC? 

Diagram attached.

Attachment 1: singleOMC.pdf
singleOMC.pdf
  14672   Thu Jun 13 22:21:44 2019 KojiConfigurationCDSPaola wireless connected to martian

SURFs had trouble connecting paola to martian via wireless.
Of course, it requires a fixed IP but it had not it yet. So I went to chiara and gave 192.168.113.110 as "paolawl". Note that the wired connection has .111 and it is "paola".

Followed the instruction on http://nodus.ligo.caltech.edu:8080/40m/14121

  14685   Fri Jun 21 19:22:40 2019 KojiConfigurationBHDReviving the single OMC BHD design?

I think a Faraday rotator rotates the polarizations in a same way for both forward and backward beam, and it's not like in this figure.
And the transmission through multiple faradays will also be a big issue.

  14692   Mon Jun 24 13:48:36 2019 KruthiConfigurationCDSGiada wireless connection

[Gautam, Kruthi]

This afternoon, Gautam helped me setup Giada to access the GigE installed for MC2. Unlike Paola, which was being used earlier, Giada has a better battery life and doesn't shutdown when the charger is unplugged. Gautam configured Giada to enable its wireless connection to Martian, just like Koji had configured Paola (https://nodus.ligo.caltech.edu:8081/40m/14672). We also rerouted  the ethernet cable we were using with the PoE adaptor from Netgear Switch in 1x2 to 1x6.

  14767   Wed Jul 17 17:56:18 2019 KojiConfigurationComputersGave resolv.conf to giada

Kruthi noticed that she could not login to rossa from giada.

I checked /etc/resolv.conf and it was

nameserver 127.0.0.1

so obviously it is useless to refer localhost (i.e. giada) as a nameserver.

I copied our usual resolv.conf to giada as following:

nameserver 192.168.113.104
nameserver 131.215.125.1
nameserver 8.8.8.8

search martian

Giada's ssh known_host had unupdated entry for rossa, so I had to clean it up, but after that we can connect to rossa from giada just by "ssh rossa".

Case closed.

  14812   Thu Jul 25 14:28:03 2019 gautamConfigurationComputersfirewalld disabled for EPICS CA

I think rana did some more changes to this workstation to make it useful for commissioning activities - but the MEDM screens were still white blanks. The problem was that the firewalld wasn't disabled (last two steps of the KThorne setup wiki). I disabled it. Now donatella can run MEDM, ndscope and StripTool. DTT doesn't work to get online data because of a "Synchronization Error", I'm not bothering with this for now. I think Kruthi successfully demonstrated the fetching of offline data with DTT.

Attachment 1: donatellaCommissioning.png
donatellaCommissioning.png
  15085   Sun Dec 8 20:48:29 2019 ranaConfigurationComputersMegatron: starts up grade

I noticed recently that Megatron was running Ubuntu 12, so I've started its OS upgrade.

  1. Unlocked the IMC + disabled the autolocker from the LockMC screen + closed the PSL shutter (IMC REFL shutter doesn't seem to do anythin)
  2. Disabled the "FSS" slow servo on the FSS screen
  3. did sudo apt-get update, sudo apt-get upgrade, and then sudo apt-get do-release-upgrade which starts the actual thing
  4. According to the internet, the LTS upgrades will go in series rather than up to 18 in one shot, so its now doing 12 -> 14 (Trusty Tapir)

Megatron and IMC autolocking will be down for awhile, so we should use a different 'script' computer this week.


Mon Dec 9 14:52:58 2019

upgrade to Ubuntu 14 complete; now upgrading to 16

  15095   Wed Dec 11 22:01:24 2019 ranaConfigurationComputersMegatron: starts up grade

Megatron is now running Ubuntu 18.04 LTS.

We should probably be able to load all the LSC software on there by adding the appropriate Debian repos.

I have re-enabled the cron jobs in the crontab.

The MC Autolocker and the PSL NPRO Slow/Temperature control are run using 'initctl', so I'll leave that up to Shruti to run/test.

  15117   Mon Jan 13 15:47:37 2020 shrutiConfigurationComputer Scripts / Programsc1psl burt restore

[Yehonathan, Jon, Shruti]

Since the PMC would not lock, we initially burt-restored the c1psl machine to the last available shapshot (Dec 10th 2019), but it still would not lock.

Then, it was burt-restored to midnight of Dec 1st, 2019, after which it could be locked.

  15125   Wed Jan 15 14:10:28 2020 JonConfigurationPSLNew EPICS database for C1PSL + C1IOO

Summary

I have completed the new EPICS channel database for the c1psl and c1ioo channels (now combined into the new c1psl Acromag machine). I've tested a small subset of channels on the electronics bench to confirm that the addressing and analog channel calibrations are correct in a general sense. At this point, we are handing the chassis off to Chub to complete the wiring of the Acromag terminals to Dsub feedthroughs. At the 40m meeting today, we identified Feb. 17-22 as a potential window for installation in the interferometer (Gautam is out of town then). Below are some implementaton details for future reference.

Analog channel calibration for Acromag

For analog input (ai) channels, the Acromag outputs raw values ranging from +/-30,000 counts, but the EPICS IOC interprets the data type as ranging from +/-2^15 = 32,768. Similarly, for analog output (ao) channels, the Acromag expects a drive signal in the range +/-30,000 counts. To achieve proper scaling, Johannes had previously changed the EGUF and EGUL fields from +/-10 V to +/-10.923 V. However, changing the engineering fields makes it much harder for a human to read off the real physical I/O range of the channel.

A better way to achieve the correct scaling is to simply set the field  ASLO=1.09225 (65,536 / 60,001) in addition to the normal EGUF and EGUL field values (+/-10 V). Setting this field forces a rescaling of the number of raw counts that works as so (assuming a 16-bit bipolar ADC or DAC, as are the Acromags):

OVAL = (RVAL * ASLO + AOFF + 2^15) * (EGUF - EGUL) / 2^16 + EGUL

In the above mapping, OVAL is the value of the channel in engineering units (e.g., V) and RVAL is its raw value in counts. It is not the case that either the ASLO/AOFF or EGUF/EGUL fields are used, but not both. The ASLO/AOFF parameters are always applied (but their default values are ASLO=1 and AOFF=0, so have no effect unless changed). The EGUF and EGUL parameters are then additionally applied if the field LINR="LINEAR" is set.

This conversion allows the engineering fields to remain unchanged from the real physical range. The ASLO value is the same for both analog input and output channels. I have implemented this on all the new c1psl and c1ioo channels and confirmed it to work using a calibrated input voltage source.

  15142   Wed Jan 22 19:17:20 2020 gautamConfigurationComputersMegatron: starts up grade

upgrade was done

cronjob testing wasn't one by one 😢 

burt snapshots were gone

i brought them back home 🏠 

Quote:

Megatron is now running Ubuntu 18.04 LTS.

  15145   Thu Jan 23 15:32:42 2020 gautamConfigurationComputersMegatron: starts up grade

The burt snapshotting is still not so reliable - for whatever reason, the number of snapshot files that actually get written looks random. For example, the 14:19 backup today got all the snaps, but 15:19 did not. There are no obvious red flags in either the cron job logs or the autoburt log files. I also don't see any clues when I run the script in a shell. It'll be good if someone can take a look at this.

  15150   Thu Jan 23 23:07:04 2020 JonConfigurationPSLc1psl breakout board wiring

To facilitate wiring the c1psl chassis and scripting loopback tests, I've compiled a distilled spreadsheet with the Acromag-to-breakout board wiring, broken down by connector. This information is extractable from the master spreadsheet, but not easily. There were also a few apparent typos which are fixed here.

The wiring assignments at the time of writing are attached below. Here is the link to the latest spreadsheet.

Attachment 1: c1psl_feedthrough_wiring.pdf
c1psl_feedthrough_wiring.pdf c1psl_feedthrough_wiring.pdf c1psl_feedthrough_wiring.pdf c1psl_feedthrough_wiring.pdf
  15158   Mon Jan 27 14:01:01 2020 JordanConfigurationGeneralRepurposed Sorenson Power Supply

The 24 V Sorenson (2nd from bottom) in the small rack west of 1x2 was repurposed to 12V 600 mA, and was run to a terminal block on the north side of 1X1. Cables were routed underneath 1X1 and 1X2 to the terminal blocks. 12V was then routed to the PSL table and banana clip terminals were added.

  15159   Mon Jan 27 18:16:30 2020 gautamConfigurationComputersSluggish megatron?

I've also been noticing that the IMC Autolocker scripts are running rather sluggishly on Megatron recently. Some evidence - on Feb 11 2019, the time between the mcup script starting and finishing is ~10 seconds (I don't post the raw log output here to keep the elog short). However, post upgrade, the mean time is more like ~45-50 seconds. Rana mentioned he didn't install any of the modern LIGO software tools post upgrade, so maybe we are using some ancient EPICS binaries. I suspect the cron job for the burt snapshot is also just timing out due to the high latency in channel access. Rana is doing the software install on the new rossa, and once he verifies things are working, we will try implementing the same solution on megatron. The machine is an old Sun Microsystems one, but the system diagnostics don't signal any CPU timeouts or memory overflows, so I'm thinking the problem is software related...

Quote:

The burt snapshotting is still not so reliable - for whatever reason, the number of snapshot files that actually get written looks random. For example, the 14:19 backup today got all the snaps, but 15:19 did not. There are no obvious red flags in either the cron job logs or the autoburt log files. I also don't see any clues when I run the script in a shell. It'll be good if someone can take a look at this.

  15164   Tue Jan 28 15:39:04 2020 gautamConfigurationComputersSluggish megatron?

There were a bunch of medm processes stalled on megatron (connected with screenshot taking). To see if they were interfering with the other scripts, I killed all of the medm processes, and commented out the line in the crontab that runs the screenshots every 10 mins. Let's see if this improves stability.

  15167   Tue Jan 28 17:36:45 2020 gautamConfigurationComputersLocal EPICS7.0 installed on megatron

[Jon, gautam]

We found that the caput commands were taking much longer to execute on megatron than on pianosa (for example). Suspecting that this had something to do with the fact that megatron was using EPICS binaries from the shared NFS drive which were compiled for a much older OS, I installed the latest stable release of EPICS on megatron. The new caput commands execute much faster. I also added the local EPICS directory to the head of the $PATH variable used by the MC autolocker and FSS Slow scripts, so that they use the new caput command. But mcup is still slow - maybe my new path definition isn't picked up and it is still using the NFS binaries? To be looked into...

Quote:

There were a bunch of medm processes stalled on megatron (connected with screenshot taking). To see if they were interfering with the other scripts, I killed all of the medm processes, and commented out the line in the crontab that runs the screenshots every 10 mins. Let's see if this improves stability.

  15168   Tue Jan 28 19:12:30 2020 JonConfigurationPSLSpare channels added to c1psl chassis

After some discussion with Gautam, I decided to build more spare channels into the new c1psl machine. This is anticipation of adding new laser and ISS channels in the near future, to avoid having to disconnect the installed chassis and pull it out of the rack. The spare channels will be wired to DB37M feedthroughs on the front side of the chassis, with enough wire length to be able to pull the breakout boards out of the front to reconfigure their wiring as needed (e.g., split off channels onto a separate connector).

To have enough overhead, this will require installing 1 additional ADC unit (XT1221) and 1 additional DAC (XT1541). We have enough spare BIO channels among the existing units (both sinking and sourcing). This will give us:

  • 13 spare ADC channels
  • 14 spare DAC channels
  • 16 spare sinking BIO channels
  • 12 spare sourcing BIO channels

The updated c1psl chassis wiring assignments are attached. It adds 4 new DB37M connectors for the spare channels (highlighted in yellow) and fixes one typo Jordan found while wiring today. The most current spreadsheet is available here.

Attachment 1: c1psl_feedthrough_wiring_v2.pdf
c1psl_feedthrough_wiring_v2.pdf c1psl_feedthrough_wiring_v2.pdf c1psl_feedthrough_wiring_v2.pdf c1psl_feedthrough_wiring_v2.pdf c1psl_feedthrough_wiring_v2.pdf
  15421   Mon Jun 22 10:43:25 2020 JonConfigurationVACVac maintenance at 11 am

The vac system is going down at 11 am today for planned maintenance:

  • Re-install the repaired TP2 and TP3 dry pumps [ELOG 15417]
  • Incorporate an auto-mailer and flag channel into the controls code for signaling tripped interlocks [ELOG 15413]

We will advise when the work is completed.

  15424   Mon Jun 22 20:06:06 2020 JonConfigurationVACVac maintenance complete

This work is finally complete. The dry pump replacement was finished quickly but the controls updates required some substantial debugging.

For one, the mailer code I had been given to install would not run against Python 3.4 on c1vac, the version run by the vac controls since about a year ago. There were some missing dependencies that proved difficult to install (related to Debian Jessie becoming unsupported). I ultimately solved the problem by migrating the whole system to Python 3.5. Getting the Python keyring working within systemd (for email account authentication) also took some time.

Edit: The new interlock flag channel is named C1:Vac-interlock_flag.

Along the way, I discovered why the interlocks had been failing to auto-close the PSL shutter: The interlock was pointed to the channel C1:AUX-PSL_ShutterRqst. During the recent c1psl upgrade, we renamed this channel C1:PSL-PSL_ShutterRqst. This has been fixed.

The main volume is being pumped down, for now still in a TP3-backed configuration. As of 8:30 pm the pressure had fallen back to the upper 1E-6 range. The interlock protection is fully restored. Any time an interlock is triggered in the future, the system will send an immediate notification to 40m mailing list. 👍

Quote:

The vac system is going down at 11 am today for planned maintenance:

  • Re-install the repaired TP2 and TP3 dry pumps [ELOG 15417]
  • Incorporate an auto-mailer and flag channel into the controls code for signaling tripped interlocks [ELOG 15413]
Attachment 1: Pumpdown-6-22-20.png
Pumpdown-6-22-20.png
ELOG V3.1.3-