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ID Date Author Type Category Subject
7025   Wed Jul 25 11:34:31 2012 EricSummarySimulationsSURF Update

I am continuing work on simulating the DARM control loop. There is now a block for the length response
function
that allows one to recover the h(t) GW input to the model. However, in order to add this
block I had to add some artificial poles to the length response function beacuse Simulink gave me errors
when the transfer function had more zeros than poles. The artificial poles are at 10^6 Hz and higher, so
that they should not affect the response function at the lower frequencies of interest. This approach
appears a bit computationally unstable though because without changing any parameters and re-running
the simulation, a different magnitude for h(t) would be calculated sometimes. A different method may be
necessary to get this working more accurately
.

By looking through the C1LSC Simulink model and the C1LSC control screens, Jenne helped me determine
which digital filters are active while the interferometer is locked
. To do this, open the C1LSC control
screen, then open the trigger matrix. Inside the trigger matrix window there is a button titled Filter
Module Triggers which opens another window that indicates which filters are triggered for a given channel,
and what values trigger them. For the y arm servo filters FM2, 3, 6, 7, 8 are triggered while in lock and
FM4 and 5 are controlled manually; I am including all of these in the model now.

I have changed the way I manipulate the output from the model for analysis, using Rana's advice. I also
improved the plotting code, now using a custom Bode plot instead.

Attached is a screenshot of the Simulink model as it currently stands, and an older implementation of the
open loop gain
. I am in the process of updating the servo filters now, and what is shown in the plot does
not include all the filter modules for the servo filter.

Attachment 1: DARM_control_loop_hendries.PNG
Attachment 2: OLG_old_hendries2.png
7064   Wed Aug 1 10:38:11 2012 EricSummaryGeneralSURF Update

Since my last update I have modified the DARM control loop model to the extent that it resembles the
measured open loop transfer function much more closely
. The phase especially is much more accurate, with
a phase margin of about 35 degrees at the unity gain frequency of 156 Hz. Right now I'm normalizing to
the unity gain frequency still to adjust the gain properly. Using the length response function from the
model, I can calibrate the error signal as well to find the simulated h(t) output. There were a number of
computational problems in calculating the length response function, but I eventually found a work-around.
Attached is an updated plot of the open loop transfer function and the length response function of the model.

This week Jamie showed me around the real-time Simulink models as well. The one specific to my project
is c1cal.mdl
. It takes the output in the form of the error and control signals from c1lsc.mdl as its
input and produces the calibrated signal as output. In order to produce the calibrated signal we need the actuation
function and the inverse of the sensing function for the model as it stands now. We also built, installed,
and restarted the c1cal model because no data was showing up in data viewer, but the problem remained
after this attempt.

Jamie and I also started on calibrating the interferometer in the traditional way. Jamie aligned the beam
splitter and the input test masses so we could take free-swinging Michelson measurements. However, taking
the data with the nds system appears to be giving different results than what is showing up in data viewer.
The goal of this measurement is to get a value for the peak to peak amplitude of the Michelson error signal.

Attachment 1: OLG_hendries.png
Attachment 2: Length_response_hendries.png
7119   Wed Aug 8 13:16:58 2012 EricSummaryGeneralSURF Update

This week I spent most of my time learning about how the interferometer is calibrated and working on the calibration itself. I also looked more into the Pound-Drever-Hall technique.

Continuing work on the free-swinging Michelson measurements, I changed the signal that I was using to C1:LSC-ASDC_OUT_DQ. This is a proper power signal so that the peak-to-peak amplitude of this error signal can be directly read off the graph. The motivation to measure this amplitude is that it must be known in order to calibrate the actuation of the input and end test masses.

Next I looked into using DTT to make some measurements. I ran the Michelson restore script in the IFO Configure screen to adjust the optics to be near alignment. Then I tweaked the precise settings in the IFO Align screen of pitch and yaw for the ITMX, ITMY, and BS. The goal with this was to minimize the magnitude of the C1:LSC-ASDC_OUT_DQ signal. After it was well-aligned, back in DTT I sent in a sine wave excitation and used a Triggered Time Response measurement to see the output. As a first test I put the excitation signal in the ASDC channel and I was able to plot the resulting OUT signal in DTT. The amplitude was different than I input due to gains between the excitation and the point of measurement, but this can easily be accounted for by adjusting the amplitude in DTT accordingly.

The next step is to work on measurements of a single arm cavity, introducing excitations there and measuring the response.

7195   Wed Aug 15 16:29:59 2012 Eric SummaryGeneralSURF Update

This week I took more data for the calibration of YARM. The summary of measurements taken is:

1. Peak-to-peak on Michelson
2. Michelson open loop
3. Excite ITMY and measure on AS55_Q_ERR
4. Excite ITMY and measure on POY11_I_ERR
5. Excite ETMY and measure on POY11_I_ERR
6. YARM open loop

Then I worked on comparing these measurements to the Simulink model of the interferometer control loop. The measured open loop transfer function of the YARM matched well with the model above about 20 Hz, after the gain was scaled properly to fit the data. Next is to fit the length response function of the model and the measurements, and then use DTT to calibrate the arm cavity's power spectrum.

6881   Wed Jun 27 14:12:44 2012 EricSummaryGeneralSURF Week 1

I started work familiarizing myself with the ELOG and some of the control systems at the 40m. I spent a fair bit of time gaining some general knowledge of the interferometer, control systems, calibration, null instruments, etc. On Friday, June 22 Yaakov and I spent the afternoon pulling cables for the beatbox that Jamie had finished up. We were able to get the cables from the rack containing the beatbox routed to the control room.

Then I started work on calibrating the beatbox. I set up the function generator to send a sine wave into the beatbox, then sent the signal from the beatbox to the oscilloscope. I compared both the input sine wave and the output from the beatbox at many frequencies, taking peak to peak measurements. I'm working on using the data to calibrate the beatbox now.

1697   Wed Jun 24 12:04:22 2009 ZachUpdateCamerasSURF entry

This week, I've been reading some literature concerning PLL and familiarizing myself with LINUX, MATLAB, and high-pass filter circuits.  In MATLAB, I started constructing matrices to be used for a beam path analysis from the laser output to the ccd camera.  I also built a simple high-pass filter on a bread-board that Joe and I are currently testing with the spectrum analyzer.

3150   Wed Jun 30 18:16:55 2010 steveUpdateSAFETYSURF safety training 2010

40m SURFs Razib Obaid, Nancy Aggarwal, Unknown Bearded SMURF, Megan Daily, Gopal Nataraj, Katharine Larson and Sharmila Dhevi received 40m specific safety training on June 23, 2010.

Attachment 1: DSC_1902.JPG
6848   Thu Jun 21 15:00:55 2012 steveUpdateSAFETYSURFs 2012 safety training

Masha, Eric, Yaakov, Liz and Sasha received 40m specific basic safety training.

Attachment 1: surfs2012.JPG
652   Wed Jul 9 15:04:22 2008 steveMetaphysicsPhotosSURFs helping hands
Surf students are helping out with baffle cleaning.
Attachment 1: surfjob.png
4902   Tue Jun 28 21:05:05 2011 JamieUpdateSUSSUS control model updated

I have updated the sus_single_control model, adjusting/cleaning up/simplifying the LSC/POS input signals, and routing new signals to the lockins. Notably one of POS inputs to the part ("lockin_in") was eliminated (see below).

The 6 inputs to the TO_COIL output matrix are now:

LSCPOS + OFFSET + ALT_POS_IN
ASCPIT + OFFSET + SUSPIT + OLPIT
ASCYAW +OFFSET + SUSYAW + OLYAW
SIDE
LOCKIN1
LOCKIN2


The ALT_POS input is used only by the ETMs for the green locking. Just outside of the sus_single_control library part in the ETM models are the green locking controls, consisting of the ETM?_ALS filter bank and the ETM?_GLOCKIN lockin, the outputs from which are summed and fed into the aforementioned ALT_POS input.

As for the SUS lockins (LOCKIN1 and LOCKIN2 in the library model), their input matrix now gets the direct inputs from the OSEMS (before filtering) and the outputs to the coils, after all filtering. These will aid in doing binary output switching tests.

All suspension models (c1sus, c1scx, c1scy) have been rebuild and restarted so that they reflect these changes.

6623   Tue May 8 09:58:17 2012 DenUpdateCDSSUS -> FB

[Alex, Den]

It was in vain to restart mx_stream yesterday as C1SUS did not see FB

controls@c1sus ~ 0$/opt/open-mx/bin/omx_info    Open-MX version 1.3.901  build: root@fb:/root/open-mx-1.3.901 Wed Feb 23 11:13:17 PST 2011  Found 1 boards (32 max) supporting 32 endpoints each:  c1sus:0 (board #0 name eth1 addr 00:25:90:06:59:f3)  managed by driver 'igb'  Peer table is ready, mapper is 00:60:dd:46:ea:ec ================================================  0) 00:25:90:06:59:f3 c1sus:0  1) 00:60:dd:46:ea:ec fb:0 // this line was missing  2) 00:14:4f:40:64:25 c1ioo:0  3) 00:30:48:be:11:5d c1iscex:0  4) 00:30:48:bf:69:4f c1lsc:0  5) 00:30:48:d6:11:17 c1iscey:0 At the same time FB saw C1SUS: controls@fb ~ 0$ /opt/mx/bin/mx_info

MX Version: 1.2.12
MX Build: root@fb:/root/mx-1.2.12 Mon Nov  1 13:34:38 PDT 2010
1 Myrinet board installed.
The MX driver is configured to support a maximum of:
 8 endpoints per NIC, 1024 NICs on the network, 32 NICs per host
===================================================================
Instance #0:  299.8 MHz LANai, PCI-E x8, 2 MB SRAM, on NUMA node 0
 Status: Running, P0: Link Up
 Network: Ethernet 10G
 
 MAC Address: 00:60:dd:46:ea:ec
 Product code: 10G-PCIE-8AL-S
 Part number: 09-03916
 Serial number: 352143
 Mapper: 00:60:dd:46:ea:ec, version = 0x00000000, configured
 Mapped hosts: 6
 
                                                        ROUTE COUNT
INDEX    MAC ADDRESS     HOST NAME                        P0
-----    -----------     ---------                        ---
   0) 00:60:dd:46:ea:ec fb:0                              1,0
   1) 00:30:48:d6:11:17 c1iscey:0                         1,0
   2) 00:30:48:be:11:5d c1iscex:0                         1,0
   3) 00:30:48:bf:69:4f c1lsc:0                           1,0
   4) 00:25:90:06:59:f3 c1sus:0                           1,0
   5) 00:14:4f:40:64:25 c1ioo:0                           1,0

For that reason when I restarted mx_stream on c1sus, the script tried to connect to the standard 00:00:00:00:00:00 address, as the true address was not specified.

Alex restarted mx on FB. Note, DAQD process will not allow one to do that until it runs, at the same time, you can't just kill it, it will restart automatically. For that reason one should open /etc/inittab and replace respawn to stop in the line

daq:345:respawn:/opt/rtcds/caltech/c1/target/fb/start_daqd.inittab

then execute inittab using init q and restart mx on the FB

controls@fb ~ 0$sudo /sbin/init q controls@fb ~ 0$ sudo /etc/init.d/mx restart

### Restarting DAQD process (or may be C1SUS) also solved the problem with guralp channels, now they are fine. Again, why this happened is unknown.

10934   Fri Jan 23 10:07:15 2015 SteveUpdateSUSSUS Drift ETMX vs ETMY

ETMX YAW stopped drifting Jan 8, 2015

 Quote: I made little scripts to go with the sus driftmon buttons, that will servo the alignment sliders until the susyaw and suspit values match the references on the driftmon screen.
Attachment 1: SUSdrift30d.png
10870   Wed Jan 7 14:35:44 2015 diegoUpdateSUSSUS Drift Monitor

The SUS Drift Monitor screen has been updated:

• removed the old dead channels from the MEDM screen;
• updated the SUS models with new 'mute' channels where the expected values should be put;
• updated the MEDM screen with the new channels
• values are still 0 since I don't know what these expected values should be, at this time

10881   Thu Jan 8 23:02:30 2015 diegoUpdateSUSSUS Drift Monitor

The MEDM screen has been updated: the new buttons, one for each optic, call the scripts/general/SUS_DRIFTMON_update_reference.py script, which measures (and averages) for 30s the current values of the POS/PIT/YAW drifts, and then sets the average as the new reference value.

763   Wed Jul 30 01:08:50 2008 ranaSummarySUSSUS Drift Screen
This is a snap of the SUS Drift screen with all of the optics biases set back to their nominal
values except for the MC which Rob aligned and I didn't feel like mis-aligning. The reference
on the screen is from 3/25 when Andrey felt that Rob had a good IFO alignment.

Anything more than a few thousand is significant and more than 10k means something is wrong:

I wailed on the PRM for awhile and was able to loosen it up a little. The LL & LR sensors now
show some life one the dataviewer. The UL & UR are still railed ~1.6 V so that means that the
optic is pitched back. With aggressive pitch wailing I can see the PRM's ULR/UR sensors go
rail to rail so that means that the magnets are still on - although they may be half busted.
If they're OK we should be able to just re-sling this guy.

Did the same on SRM. The OSEM values have shifted on these, but not disastorously. The SIDE,
however, is completely unresponsive. The little signal I see when driving is is probably just
capacitive pickup in the cables. Have to vent to fix this one.

ITMX Has good life in all but the LR & UR channels. They respond, but the signal is very weak.
Seems like these magnets have not fallen off but that they are not between the LED/PD anymore.

ITMY seems ok. Check the spectra to be sure.

BS seems ok as well. Swings freely and no kinks in the swinging sensor waveforms. Check the spectra.
Attachment 1: infection-2.png
970   Fri Sep 19 01:55:41 2008 ranaSummarySUSSUS Drift Screen Updated
I wrote 2 matlab scripts to update the SUS DRIFT screen:
- setsval.m   uses mDV to get the minute trend from some specified start time
and duration in the past. It then writes that 'good' value to the
.SVAL field of the SUSPOS, SUSPIT, and SUSYAW records for all the
optics

- setHILO.m   reads the .SVAL field and then sets the alarm levels and severity
for the same records given a "sigma" as an argument. i.e. 1 sigma = HIGH,
2 sigma = HIHI.

Attached is the new screen. WE can now use this to judge when the optics have moved alot.

If someone will edit the BURT .req file to have these subfields
(.HIHI .HIGH .LOW .LOLO .HHSV .HSV .LSV .LLSV) then they will come back after a reboot as well.

Below I'm also attaching the matlab code for people at the observatories who don't have
Attachment 1: infection-3.png
Attachment 2: setsvals.m
function varargout = setsvals(varargin)
% SETSVALS
% sets the SVAL records for the SUS

debug = 0;

if nargin < 2
error('Needs 2 arguments.')
elseif nargin > 2

... 56 more lines ...
Attachment 3: setHILO.m
function setHILO(varargin)
%  SETHILO
%  Ex.  setHILO(1000);
%      this sets the SUS alarm levels to be 1000 counts
%      from the nominal

% 1 for debugging
debug_flag = 0;

if nargin == 1

... 62 more lines ...
10924   Tue Jan 20 19:32:06 2015 JenneUpdateSUSSUS Drift restore scripts

I made little scripts to go with the sus driftmon buttons, that will servo the alignment sliders until the susyaw and suspit values match the references on the driftmon screen.

3144   Wed Jun 30 12:01:20 2010 josephbUpdateCDSSUS IO Chassis

I spent this morning populating the SUS IO Chassis and getting it ready for installation into the 1Y4 rack.  I discovered I'm lacking the internal cables to connect the ADC/DAC boards to the AdL adapter boards that also go in the chassis (D0902006 and D0902496).  I'm not sure where Alex got the cables he used for the end IO chassis he had put in.  I'll be going to Downs after the meeting today either to get cables or parts for cables, and get the SUS chassis wired up fully.

I'd also like to confirm with Alex that the OSS-MAX-EXP-ELB-C board that goes in the IO chassis matches the host interface board that goes in the computer (OSS-HIB2-PE1x4-1x4 Re-driver HIB, since we spent half a day the last time we installed an IO chassis determining that one of the pair was bad or didn't match.

The SUS chassis has been populated in the following way:

Treton Board

Slot 2 DAC PMC66-16AO16-16-F0-OF

Slot 3-6 BO Contec DIO-1616L-PE Isolated Digital IO board

Slot 8-9 DAC PMC66-16AO16-16-F0-OF

Back  Board

13589   Wed Jan 31 15:27:55 2018 gautamUpdateSUSSUS MEDM master screens updated

I've often gotten confused by the labeling on the SUS MEDM screens about the coil "Vmon" fields - they're labelled as "30 Hz HPF", and indeed this is one of the many readbacks available on the coil driver board. But the actual EPICS channel that is being displayed in this field is from the "EPICS VMON" monitor point on the coil driver board. It has a gain of 1/2, so the actual voltage going to the coil is twice the channel value. Today, I fixed the SUS master screen to avoid this confusion - new labeling is shown in Attachment #1.

Attachment 1: NewSUSmaster.png
8919   Wed Jul 24 19:21:56 2013 JamieHowToSUSSUS MEDM screen modernization

I started poking around at what we want for new SUS MEDM screens.  Rana and I decided we'd start with the ASC TIPTILT screens:

It's missing some things (like SIDE OSEMS) but it should provide a good starting point.

I copied the entire <userapps>/asc/common/medm/asctt directory to a new directory in our sus area:

controls@rossa:/opt/rtcds/userapps/release 0$cp -a asc/common/medm/asctt sus/c1/medm/new  I then removed all the useless file name prefixes. We still need to go through and sed out all the ASC stuff in the MEDM files themselves. It makes heavy use of macro substitution, which is good (it's what we're using now). So once we clean up all the channel names, we should just be able to swap out the pointers in our overview screens to the new screens (or rename things). In the mean time, during development, you can run: controls@rossa:/opt/rtcds/userapps/release 0$ medm -x -macro "IFO=C1,ifo=c1,OPTIC=ITMX" sus/c1/medm/new/OVERVIEW.adl


14261   Thu Oct 18 00:27:37 2018 KojiUpdateSUSSUS PD Whitening board inspection

[Gautam, Koji]

As a part of the preparation for the replacement of c1susaux with Acromag, I made inspection of the coil-osem transfer function measurements for the vertex SUSs.

The TFs showed typical f^-2 with the whitening on except for ITMY UL (Attachment 1). Gautam told me that this is a known issue for ~5 years.
We made a thorough inspection/replacement of the components and identified the mechanism of the problem.
It turned out that the inputs to MAX333s are as listed below.

 Whitening ON Whitening OFF UL ~12V ~8.6V LL 0V 15V UR 0V 15V LR 0V 15V SD 0V 15V

The switching voltage for UL is obviously incorrect. We thought this comes from the broken BIO board and thus swapped the corresponding board. But the issue remained. There are 4 BIO boards in total on c1sus, so maybe we have replaced a wrong board?

Initially, we thought that the BIO can't drive the pull-up resistor of 5KOhm from 15V to 0V (=3mA of current). So I have replaced the pull-up resistor to be 30KOhm. But this did not help. These 30Ks are left on the board.

Attachment 1: 43.png
16447   Wed Nov 3 16:55:23 2021 Ian MacMillanSummarySUSSUS Plant Plan for New Optics

[Ian, Tega, Raj]

This is the rough plan for the testing of the new suspension models with the created plant model. We will test the suspensions on the plant model before we implement them into the full

• Get State-space matrices from the surf model for the SOS. Set up simplant model on teststand
• The state-space model is only 3 degrees of freedom. (even the surf's model)
• There are filter modules that have the 6 degrees of freedom for the suspensions. We will use these instead. I have implemented them in the same suspension model that would hold the state space model. If we ever get the state space matrices then we can easily substitute them.
• Load new controller model onto test stand. This new controller will be a copy of an existing suspension controller.
• Hook up controller to simplant.  These should form a closed loop where the outputs from the controller go into the plant inputs and the plant outputs go to the controller inputs.
• Do tests on set up.
• Look at the step response for each degree of freedom. Then compare them to the results from an existing optic.
• Also, working with Raj let him do the same model in python then compare the two.
• Make sure that the data is being written to the local frame handler.

MEDM file location

/opt/rtcds/userapps/release/sus/common/medm/hsss_tega_gautam

run using

For ITMX display, use:

16460   Tue Nov 9 13:40:02 2021 Ian MacMillanSummaryComputer Scripts / ProgramsSUS Plant Plan for New Optics

[Ian, Tega]

After talking with Rana we have an updated plan. We will be working on this plan step by step in this order.

1. Remove c1sim from the test stand rack and move it to the rack in the office next to the printer. When connecting it we will NOT connect it to the Martian network! This is to make sure that nothing is connected to the 40m system and we can't mess anything up.
2. Once we have moved the computer over physically, we will need to update anyone who uses it on how to connect to it. The way we connect to it will have changed.
3. Now that we have the computer moved and everyone can connect to it we will work on the model. Currently, we have the empty models connected.
1. recompile the model since we moved the computer.
2. verify that nothing has changed in the move and the model can still operate and compile properly
4. The model has the proper structure but we need to fill it with the proper filters and such
1. For the Plant model
1. To get it up and running quickly we will use the premade plant filters for the plant model. These filters were made for the c1sup.mdl and should work in our modified plant model. This will allow us to verify that everything is working. And allow us to run tests on the system.
2. We need to update the model and add the state space block. (we are skipping this step for now because we are fast-tracking the testing)
1. Check with Chris to make sure that this is the right way to do it. I am pretty sure it is, but I don't know anything
2. Make the 6 DOF state-space matrix. We only have a three DOF one. The surf never made a 6 DOF.
3. Make the block to input into the model
4. make a switch that will allow us to switch between the state-space model and the filter block
2. For the controller
1. Load filter coefficients for the controller model from one of the current optics and use this as a starting point.
2. Add medm screens for the controller and plant. We are skipping this for now because we want results and we don't care if the screens look nice and are useable at the moment.
5.  Test the model
1. we will take an open-loop transfer function of all six of the DOFs to all other DOFs which will leave us with 36 TFs. Many will be zero
1. If you are looking at this post then we are measuring transfer functions from the blue flags to the green flags across the plant model.
2. We will want to look at the TFs across the controller

16461   Tue Nov 9 16:55:52 2021 Ian MacMillanSummaryComputer Scripts / ProgramsSUS Plant Plan for New Optics

[Ian, Tega]

We have moved c1sim computer from the test stand to the server rack in the office area. (see picture)

It is connected to the general campus network. Through the network switch at the top of the rack. This switch seeds the entire Martian network.

Test to show that I am not lying:

1. you can ping it or ssh into it at
controls@131.215.114.116
Using the same password as before. Notice this is not going through the nodus network.

c1sim is now as connected to the 40m network as my mom's 10-year-old laptop.

unfortunately, I have not been able to get the x2go client to connect to it. I will have to investigate further. It is nice to have access to the GUI of c1sim occasionally.

Attachment 1: IMG_8107.JPG
16462   Tue Nov 9 18:05:03 2021 Ian MacMillanSummaryComputer Scripts / ProgramsSUS Plant Plan for New Optics

[Ian, Tega]

Now that the computer is in its new rack I have copied over the filter two files that I will use in the plant and the controller from pianosa:/opt/rtcds/caltech/c1/chans to the docker system in c1sim:/home/controls/docker-cymac/chans. That is to say, C1SUP.txt -> X1SUP.txt and C1SUS.txt -> X1SUS_CP.txt, where we have updated the names of the plant and controller inside the txt files to match our testing system, e.g. ITMX -> OPT_PLANT in plant model and ITMX -> OPT_CTRL in the controller and the remaining optics (BS, ITMY, PRM, SRM) are stripped out of C1SUS.txt in order to make X1SUS_CP.txt.

Once the filter files were copied over need to add them to the filters that are in my models to do this I run the commands:

$cd docker-cymac$  eval $(./env_cymac)$  ./login_cymac  #  cd /opt/rtcds/tst/x1/medm/x1sus_cp  #  medm -x X1SUS_OPT_PLANT_TM_RESP.adl

see this post for more detail

Unfortunately, the graphics forwarding from the docker is not working and is giving the errors:

Error: Can't open display:

This means that the easiest way to add the filters to the model is through the GUI that can be opened through X2go client. It is probably easiest to get that working. graphics forwarding from inside the docker is most likely very hard.

unfortunately again x2go client won't connect even with updated IP and routing. It gives me the error: unable to execute: startkde. Going into the files on c1sim:/usr/bin and trying to start startkde by myself also did not work, telling me that there was no such thing even though it was right in front of me.

16466   Mon Nov 15 15:12:28 2021 Ian MacMillanSummaryComputer Scripts / ProgramsSUS Plant Plan for New Optics

[Ian, Tega]

We are working on three fronts for the suspension plant model:

1. Filters
1. We now have the state-space matrices as given at the end of this post. From these matrices, we can derive transfer functions that can be used as filter inputs. For a procedure see HERE. We accomplish this using Matlab's built-in ss(A,B,C,D); function. then we make it discrete using c2d(sys, 1/f); this gives us our discrete system running at the right frequency. We can get the transfer functions of either of these systems using tf(sys);
2. from there we can copy the transfer functions into our photon filters.  Tega is working on this right now.
2. State-Space
1. We have our matrices as listed at the end of this post. With those compiled into a discrete system in MatLab we can use the code Chris made called rtss.m to convert this system into a .c file and a .h file.
2. from there we have moved those files under the userapps folder in the docker system. then we added a c-code block to our .mdl model for the plant and pointed it at the custom c file we made. See section 7.2 of T080135-v10
3. We have done all this and this should implement a custom state-space function into our .mdl file. the downside of this is that to change our SS model we have to edit the matrices we can't edit this from an medm screen. We have to recompile every time.
3. Python Check
1. This python check is run by Raj and will take in the state-space matrices which are given then will take transfer functions along all inputs and outputs and will compare them to what we have from the CDS model.

Here are the State-space matrices:

$A=\begin{bmatrix} 0 & 1 & 0 & 0 & 0 & 0 & 0 & 0 \\ -\omega_x^2(1+i/Q_{x}) & -\gamma_x & \omega_xb & 0 & 0 & 0 & 0 & 0 \\ 0 & 0 & 0 & 1 & 0 & 0 & 0 & 0 \\ \frac{\omega_{\theta}^2}{l+b} & 0 & -\omega_{\theta}^2(1+i/Q_{\theta}) & -\gamma_{\theta} & 0 & 0 & 0 & 0 \\ 0 & 0 & 0 & 0 & 0 & 1 & 0 & 0 \\ 0 & 0 & 0 & 0 & -\omega_{\phi}^2(1+i/Q_{\phi}) & -\gamma_{\phi} & 0 & 0 \\ 0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 \\ 0 & 0 & 0 & 0 & 0 & 0 & -\omega_{y}^2(1+i/Q_{y}) & -\gamma_{y}\end{bmatrix}$

$B=\begin{bmatrix} 0 & 0 & 0 & 0 \\ \frac{1}{m} & 0 & 0 & 0 \\ 0 & 0 & 0 & 0 \\ 0 & \frac{R_m}{I_{\theta}} & 0 & 0 \\ 0 & 0 & 0 & 0 \\ 0 & 0 & \frac{R_m}{I_{\phi}} & 0 \\ 0 & 0 & 0 & 0 \\ 0 & 0 & 0 & \frac{1}{m} \end{bmatrix}$      $C=\begin{bmatrix} 1 & 0 & 0 & 0 & 0 & 0 & 0 & 0 \\ 0 & 0 & 1 & 0 & 0 & 0 & 0 & 0 \\ 0 & 0 & 0 & 0 & 1 & 0 & 0 & 0 \\ 0 & 0 & 0 & 0 & 0 & 0 & 1 & 0 \end{bmatrix}$      $D=\begin{bmatrix} 0 & 0 & 0 & 0 \\ 0 & 0 & 0 & 0 \\ 0 & 0 & 0 & 0 \\ 0 & 0 & 0 & 0 \end{bmatrix}$

A few notes: If you want the values for these parameters see the .yml file or the State-space model file. I also haven't been able to find what exactly this s is in the matrices.

UPDATE [11/16/21 4:26pm]: I updated the matrices to make them more general and eliminate the "s" that I couldn't identify.

The input vector will take the form:

$\begin{bmatrix} x \\ \dot{x} \\ \theta \\ \dot{\theta} \\ \phi \\ \dot{\phi} \\ y \\ \dot{y} \end{bmatrix}$

where x is the position, theta is the pitch, phi is the yaw, and y is the y-direction displacement

16469   Tue Nov 16 17:29:49 2021 Ian MacMillanSummaryComputer Scripts / ProgramsSUS Plant Plan for New Optics

[Ian, Tega]

Updated A, B, C, D matrices for the state-space model to remove bugs in the previous estimate of the system dynamics. Updated the last post to represent the current matrixes.

We used MatLab to get the correct time-series filter coefficients in ZPK format and added them to the filters running in the TM_RESP filter matrix.

Get the pos-pos transfer function from the CDS model. Strangely, this seems to take a lot longer than anticipated to generate the transfer function, even though we are mainly probing the low-frequency behavior of the system.

For example, a test that should be taking approximately 6 minutes is taking well over an hour to complete. This swept sine (results below) was on the low settings to get a fast answer and it looks bad. This is a VERY basic system it shouldn't be taking this long to complete a Swept sine TF.

Noticed that we need to run eval $(./env_cymac) every time we open a new terminal otherwise CDS doesn't work as expected. Since this has been the source of quite a few errors already, we have decided to put it in the startup .bashrc script. loc=$(pwd) cd ${HOME}/docker-cymac/ eval$(./env_cymac) cd ${loc} Attachment 1: x_x_TF1.pdf 16477 Thu Nov 18 20:00:43 2021 Ian MacMillanSummaryComputer Scripts / ProgramsSUS Plant Plan for New Optics [Ian, Raj, Tega] Here is the comparison between the results of Raj's python model and the transfer function measurement done on the plant model by Tega and me. As You can see in the graphs there are a few small spots of disagreement but it doesn't look too serious. Next we will measure the signals flowing through the entire plant and controller. For a nicer (and printable) version of these plots look in the zipped folder under Plots/Plant_TF_Individuals.pdf Attachment 1: Final_Plant_Testing.zip 16478 Mon Nov 22 16:38:26 2021 TegaSummaryComputer Scripts / ProgramsSUS Plant Plan for New Optics [Tega, Ian] TODO 1. Investigate cross-coupling btw the various degrees of freedom (dof) - turn on noise for each dof in the plant model and measure the transfer function of the other dofs. 2. Get a closed-loop transfer function using noise injection and give a detailed outline of the procedure in elog - IN1/IN2 for each TM_RESP filter while the others are turned off. 3. Derive analytic model of the closed-loop transfer functions for comparison. 4. Adapt control filters to fit optimized analytical solutions. 16615 Mon Jan 24 17:10:25 2022 TegaSummaryComputer Scripts / ProgramsSUS Plant Plan for New Optics [Ian, Tega] Connected the New SUS screens to the controller for the simplant model. Because of hard-coded links in the medm screen links, it was necessary to create the following path in the c1sim computer, where the new medm screen files are located: /opt/rtcds/userapps/trunk/sus/c1/medm/templates/NEW_SUS_SCREENS We noticed a few problems: 1. Some of the medm files still had C1 hard coded, so we need to replace them with$IFO instead, in order for the custom damping filter screen to be useful.

2. The "Load coefficient" button was initially blank on the new sus screen, but we were able to figure out that the problem came from setting the top-level DCU_ID to 63.

medm -x -macro "IFO=X1,OPTIC=OPT_CTRL,DCU_ID=63" SUS_SINGLE_OVERVIEW.adl

[TODO]

Get the data showing the controller damping the pendulum. This will involve tweaking some gains and such to fine-tune the settings in the controller medm screen. Then we will be able to post some data of the working controller.

[Useful aside]

We should have a single place with all the instructions that are currently spread over multiple elogs so that we can better navigate the simplant computer.

Attachment 1: Screen_Shot_2022-01-24_at_5.33.15_PM.png
16626   Thu Jan 27 16:40:57 2022 TegaSummaryComputer Scripts / ProgramsSUS Plant Plan for New Optics

[Ian, Paco, Tega]

Last night we set up the four main matrices that handle the conversion between the degrees of freedom bases and the sensor bases. We also wrote a bash script to automatically set up the system. The script sets the four change of bases matrices and activates the filters that control the plant. this script should fully set up the plant to its most basic form. The script also turns off all of the built-in noise generators.

After this, we tried damping the optic. The easiest part of the system to damp is the side or y motion of the optic because it is separate from the other degrees of freedom in both of the bases. We were able to damp that easily. in attachment 1 you can see that the last graph in the ndscope screen the side motion of the optic is damped. Today we decided to revisit the problem.

Anyways, looking at the problem with fresh eyes today, I noticed the in pit2pit coupling has the largest swing of all the plant filters and thought this might be the reason why the inputs (UL,UR,LR,LL) to the controller was hitting the rails for pit DoF. I reduce the gain of the pit2pit filter then slowly increased it back to one. I also reduced the gain in the OSEM input filter from 1 to 1/100. The attached image (Attachment2) is the output from this trial. This did not solve the problem. The output when all OSEM input filter gain set to one is shown in Attachment2.

We will try to continue to tweak the coefficients. We are probably going to ask Anchal and Paco to sit down with us and really hone in on the right coefficients. They have more experience and should be able to really get the right values.

Attachment 1: simplant_control_1.png
Attachment 2: simplant_control_0.png
16645   Thu Feb 3 17:15:23 2022 TegaSummaryComputer Scripts / ProgramsSUS Plant Plan for New Optics

Finally got the SIMPLANT damping to work following Rana's suggestion to try damping one DoF at a time, woo-hoo!

At first, things didn't look good even when we only focus on the POS DoF. I then noticed that the input value (X1:SUS-OPT_PLANT_TM_RESP_1_1_IN1) to the plant was always zero. This was odd bcos it meant the control signal was not making its way to the plant. So I decided to look at the sensor data

(X1:SUS-OPT_PLANT_COIL_IN_UL_OUTPUT, X1:SUS-OPT_PLANT_COIL_IN_UR_OUTPUT, X1:SUS-OPT_PLANT_COIL_IN_LR_OUTPUT, X1:SUS-OPT_PLANT_COIL_IN_LL_OUTPUT)

that adds up via the C2DOF matrix to give the POS DoF and I noticed that these interior nodes can take on large values but always sum up to zero because the pair (UL, LL) was always the negative of (UR,LR). These things should have the same sign, at least in our case where only the POS DoF is excited, so I tracked the issue back to the alternating (-,+,-,+,-) convention for the gains

(X1:SUS-OPT_CTRL_ULCOIL_GAIN, X1:SUS-OPT_CTRL_URCOIL_GAIN, X1:SUS-OPT_CTRL_LRCOIL_GAIN, X1:SUS-OPT_CTRL_LLCOIL_GAIN, X1:SUS-OPT_CTRL_SDCOIL_GAIN)

of the Coil Output filters used in the real system, which we adopted in the hopes that all was well. Anyways, I changed them all back to +1. This also means that we need to change the sign of the gain for the SIDE filter, which I have done also (and check that it damps OK). I decided to reduce the magnitude of the SIDE damping from 1 to 0.1 so that we can see the residuals since the value of -1 quickly sends the error to zero.  I also increased the gain magnitude for the other DoF to 4.

When looking at the plot remember that the values actually represent counts with a scaling of 2^15 (or 32768) from the ADC. I switched back to the original filters on FM1 (e.g. pit_pit ) without damping coefficients present in the FM2 filter (e.g. pit_pit_damp).

FYI, Rana used the ETMY suspension MEDM screen to illustrate the working of the single suspension to me and changed maybe POS and PITCH gains while doing so.

Also, the Medify purifier 'replace filter' indicator issue occurred bcos the moonlight button should have been pressed for 3 seconds to reset the 'replace filter' indicator after filter replacement.

Attachment 1: Screen_Shot_2022-02-03_at_8.23.07_PM.png
16654   Wed Feb 9 14:34:27 2022 IanSummaryComputer Scripts / ProgramsSUS Plant Plan for New Optics

Restarted the C1sim machine at about 12:30 to help diagnose a network problem. Everything is back up and running

Attachment 1: SummaryMdemScreen.png
8747   Tue Jun 25 22:50:12 2013 ranaUpdateSUSSUS Screens generation problems?

From the ALS overview screen, opening up the ETMX and ETMY screens gives these white fields. The PV info indicates that the blank fields were made with some macro variable substitution that didn't work well.

Why are these different from the SUS screens I get from the sitemap?

8152   Sun Feb 24 00:14:28 2013 ManasaUpdateSUSSUS Summary

I tried to fix the alarms for sensors on the SUS summary screen. I checked earlier elogs and found the setSensors.py script.

I received errors while running the script and pianosa was refused connection to nds. Yuta suspects problems with the lib directory.

Jamie! Can you fix this?

8154   Sun Feb 24 17:54:34 2013 ranaUpdateSUSSUS Summary

I asked John Z to talk with Jamie and then install a new NDS2 server software for us. Jamie may know if this happened or was foiled by the linux1 RAID failure.

In any case, our pyNDS stuff ought to be able to talk to NDS2 or our old NDS1 stuff, I hope.

5318   Mon Aug 29 16:27:34 2011 ManuelConfigurationSUSSUS Summary Screen

I edited the C1SUS_SUMMARY.adl file and set the channels in alarm mode to show the values in green, yellow and red according to the values of the thresholds (LOLO, LOW, HIGH, HIHI)

I wrote a script in python, which call the command ezcawrite and ezcaread, to change the thresholds one by one.

You can call this program with a button named "Change Thresholds one by one" in the menu come down when you click the  button.

I'm going to write another program to change the thresholds all together.

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
Attachment 2: 160706_ITMX_VMON2.pdf
Attachment 3: 160706_ITMX_VMON1.pdf
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.

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.

4812   Mon Jun 13 19:26:42 2011 Jamie, JoeConfigurationCDSSUS binary IO chassis 2 and 3 moved from 1X5 to 1X4

While preping 1X4 for installation of c1lsc, we removed some old VME crates that were no longer in use.  This freed up lots of space in 1X4.  We then moved the SUS binary IO chassis 2 and 3, which plug into the 1X4 cross-connect, from 1X5 into the newly freed space in 1X4.  This makes the cable run from these modules to the cross connect much cleaner.

4814   Tue Jun 14 09:24:36 2011 steveConfigurationPhotosSUS binary IO chassis 2 and 3 moved from 1X5 to 1X4

 Quote: While preping 1X4 for installation of c1lsc, we removed some old VME crates that were no longer in use.  This freed up lots of space in 1X4.  We then moved the SUS binary IO chassis 2 and 3, which plug into the 1X4 cross-connect, from 1X5 into the newly freed space in 1X4.  This makes the cable run from these modules to the cross connect much cleaner.

Are we keeping these?

Attachment 1: P1070891.JPG
Attachment 2: P1070893.JPG
6182   Mon Jan 9 23:52:15 2012 kiwamuUpdateCDSSUS channels not accessible from dataviewer

[John / Kiwamu]

We found that some of the suspensions channels (for example C1:SUS-BS_POS_IN1 and etc) were not accessible from dataviewer for some reasons.

So far it seems none of the channels associated with c1sus are accessible from dataviewer.

4780   Thu Jun 2 16:23:42 2011 JamieUpdateSUSSUS control models updated to use new sus_single_control library part

A new library part was made for the single suspension controller (it was originally made from the c1scx controller), using the following procedure:

1. Opened c1scx model (userapps/trunk/sus/c1/models/c1scx)
2. Cut ETMX subsystem block out of SUS subsystem
3. Pasted ETMX block into new empty library, and renamed it C1_SUS_SINGLE_CONTROL
4. Tweaked names of inputs, and generally cleaned up internals (cosmetically)
5. Saved library to: userapps/trunk/sus/c1/models/lib/sus_single_control.mdl

Once the new sus_single_control library part was made and the library was committed to the cds_user_apps repo, I replaced all sus controller subsystems with this new part, in:

• c1scx
• c1scy
• c1sus (x5 for each vertex mass)

All models were rebuild, installed, and tested, and everything seems to be working fine.

12315   Wed Jul 20 13:58:55 2016 SteveUpdateSUSSUS damping out of vac chamber

Cheater cable to be used in clean room pitch gluing alingment.

Satelite amp needs to be there.

Atm 2-3, The ETMs  suspension damping cable  are connected at the end racks. All others go to 1X5

Atm 4-5, The other end of this cable in the high cable tray at 1X3 as shown. We'll disconnect the shorty and move the end to ETMX ( or any sus at 1X5 )

Attachment 1: ETMXrack.jpg
Attachment 2: fromETMX-satBox.jpg
Attachment 3: susDampingSatboxCab.jpg
Attachment 4: susDampingSatboxCabl.jpg
5461   Mon Sep 19 15:41:48 2011 JenneUpdateSUSSUS diag stuff... just so I remember what I'm doing

The following optics were kicked:
ETMX
Mon Sep 19 15:39:44 PDT 2011
1000507199

5471   Mon Sep 19 22:47:44 2011 JenneUpdateSUSSUS diag stuff... just so I remember what I'm doing

The last person out tonight should run the following scripts:

In Matlab:

/opt/rtcds/caltech/c1/scripts/SUS/peakFit/writeMultiSUSinmat.m

In command line:

/opt/rtcds/caltech/c1/scripts/SUS/freeswing all

Then in the morning, someone should do a BURT restore to early today (to get the default matricies back), and also restore the watchdogs.

Thanks!

5485   Tue Sep 20 16:45:09 2011 JenneUpdateSUSSUS diag stuff... just so I remember what I'm doing

Has the Q been checked?  Still in progress...

 Optic POS PIT YAW SIDE ITMX done done done done ITMY done done fine?? done ETMX done done done done ETMY done done done done BS done done done done PRM done done done done SRM done done done done MC1 MC2 MC3

So, update as of 6:17pm:  I have tuned the damping gains for all IFO optics.  Everything is good, except for ITMY Yaw.  It's probably fine, the optic damps okay, but it doesn't look like a nice clean ringdown.  I haven't taken the time to go back and look at it again.

I have to go to a dinner, but later (probably in the morning, so I don't disturb evening locking) I'll check the MC Qs.

5493   Wed Sep 21 00:34:29 2011 ranaUpdateSUSSUS diag stuff... just so I remember what I'm doing

ETMX was ringing up when it was mis-aligned for Y arm locking. I restored the input matrix to something more diagonal and its now damping again. Needs more work before we can use the calculated matrix.

11569   Thu Sep 3 19:52:24 2015 ranaSummarySUSSUS drift monitor

Since Andrey's SUS Drift mon screen back in 2007, we've had several versions which used different schemes and programming languages. Diego made an update back in January.

Today I added his stuff to the SVN since it was lost in the NFS disks somewhere. Its in SUS/DRIFT_MON/.

Since we've been updating our userapps directory recently to pull in the screens and scripts from the sites, we also got a copy of the Thomas Abbott drift mon stuff which is better (Diego actually removed the yellow/red functionality as part of the 'upgrade'), but more complicated. For now we have the old one. I updated the good values with all optics roughly aligned just a few minutes ago.

Attachment 1: 07.png
ELOG V3.1.3-