Krishna, Jim, Ryan,

This morning, we tried some different blend filter and sensor correction configurations on the ISI at ETMX to see if we could improve the low-frequency performance of the platform.

To give some background, the nominal configuration along X axis, at present, is the 45 mHz blends and the LLO ("0.43 Hz only") sensor correction. The very low blend frequency amplifies the motion of Stage 1, likely through tilt reinjection. We wondered if we could do better by going to a higher blend and relying on a broadband low-frequency sensor correction, which uses the tilt-free super-sensor. We used the CPS sensors as the witness sensors, which should be reliable below 0.1 Hz and ST1 T240 as at higher frequencies.

The first attached plot shows the Stage 1 T240 X sensor ASD for the following configurations:

1. Red - 90 mHz blend and Low-Frequency Sensor Correction (LF SC, also known as Rich's filter or Z sensor correction filter).

2. Blue - 90 mHz blend, LF SC and BRS off (no tilt-subtraction).

3. Green - 45 mHz blend, LF SC with tilt-subtraction.

4. Brown - 45 mHz blend, LF SC with no tilt-subtraction.

5. Magenta - Nominal configuration - 45 mHz blend, LLO SC.

The CPS (before sensor correction) signals for the above configurations are shown on the second plot. These should be used as an estimate of the platform motion at low frequencies. The third plot shows an example of the tilt-subtraction. Wind speeds were between 5-10 mph at EX.

As expected (and seen before 15270), the Green/Brown configurations offer best isolation at the microseism. The rms CPS signal for Case 3 is about the same as Case 5. Turning BRS off shows the clear re-injection of tilt in Case 4.

In Case 1/2, there is still a factor of ~5-10 reduction at the microseism and the usual factor of ~200 at 0.43 Hz. The slight surprise was that in Case 1/2 there was a clear amplification of the primary microseism by factor of 4-5 which limits the rms motion of Stage 1. It is not clear why this is being amplified and is worth investigating further.

The tests were concluded by 9:30 AM and the ISI was returned to the nominal configuration.

I've moved around filters  (and gains) that are used in the OpLev damping, so that we can make try to increase the bandwidth of our DHARD WFS without driving through the high Q filters that have been used in P2P and Y2Y in the L2 drivealign matrix.  

Even though we aren't currently using Yaw OpLev damping on either mass, I did the same for Yaw.  Before and after screenshots attached.  

The EY 02 Dust monitor has repeatedly gone off this morning, so I disabled it from the medm alarm manager screen. Not sure if it is something anyone has looked into or not.

Fil and Kiwamu,

The following cameras are now reachable from the analog camera screen:

• IMC REFL RFPD
• IMC WFS A
• IMC WFS B

model restarts logged for Mon 02/Feb/2015
2015_02_02 10:28 h1lsc
2015_02_02 10:34 h1broadcast0
2015_02_02 10:34 h1dc0
2015_02_02 10:34 h1fw1
2015_02_02 10:34 h1nds0
2015_02_02 10:34 h1nds1
2015_02_02 10:35 h1nds0
2015_02_02 10:36 h1fw0
2015_02_02 13:41 h1fw0
2015_02_02 20:29 h1fw1
2015_02_02 21:30 h1fw1

LSC code change with associated DAQ restart. several unexpected fw restarts

model restarts logged for Tue 03/Feb/2015
2015_02_03 10:28 h1iopiscex
2015_02_03 10:28 h1iopiscey
2015_02_03 10:28 h1iscex
2015_02_03 10:30 h1iscex
2015_02_03 10:37 h1fw0
2015_02_03 10:38 h1iscex
2015_02_03 10:40 h1iscey
2015_02_03 10:41 h1iscey
2015_02_03 10:46 h1alsex
2015_02_03 10:47 h1alsey
2015_02_03 10:49 h1odcx
2015_02_03 10:49 h1odcy
2015_02_03 10:49 h1pemex
2015_02_03 10:51 h1hpietmx
2015_02_03 10:51 h1hpietmy
2015_02_03 10:51 h1pemey
2015_02_03 10:51 h1susetmx
2015_02_03 10:51 h1susetmy
2015_02_03 10:52 h1fw1
2015_02_03 10:52 h1lsc
2015_02_03 10:54 h1asc
2015_02_03 11:10 h1broadcast0
2015_02_03 11:10 h1dc0
2015_02_03 11:10 h1fw0
2015_02_03 11:10 h1fw1
2015_02_03 11:10 h1nds0
2015_02_03 11:10 h1nds1
2015_02_03 12:38 h1broadcast0
2015_02_03 12:38 h1dc0
2015_02_03 12:38 h1fw0
2015_02_03 12:38 h1fw1
2015_02_03 12:38 h1nds0
2015_02_03 12:38 h1nds1
2015_02_03 13:21 h1pemex
2015_02_03 13:28 h1pemex
2015_02_03 13:42 h1pemey
2015_02_03 14:11 h1alsey
2015_02_03 14:15 h1alsex
2015_02_03 14:35 h1alsex
2015_02_03 14:46 h1alsex
2015_02_03 14:46 h1alsey
2015_02_03 16:51 h1alsey

X1PLC1 10:18 2/3 2015

X1PLC2 10:18 2/3 2015

X1PLC3 10:18 2/3 2015

Maintenance Day. ISC end station model restarts with associated DAQ restarts. Jumbo frame upgrade of both frame writers. Bi-weekly restart of h1ecatx1. No unexpected restarts.

SEI: Jim needs DRMI to test configuration changes.

CDS: Investigations on the floor for future PSL shutdown.

3IFO: No disruptive activity.

Commisioners: Last night success for 40sec lock!

Facilities: Bean tube cleaning continues. Next week they will be on the road with cones out.

Safety Meeting: Top 10 Safety Hazards

Safe Safe!!

At 1616utc, I changed the epics PID Proportional and Integral parameters from 35 & 0.45 to 20 & 0.07.  These later numbers are what VincentL derived shown in E1100508 in June 2011.  Vincent's Plant included no chambers, so it makes sense that these parameters are not ideal.  But, in an effort to reduce the coupling of the sensor noise, these lower magnitude parameters should lower our UGF and this coupling.  We'll look at coupling to HEPI and ISI signals after a couple hours.

• We changed the sensor for the DHARD WFS from AS B 45 Q to AS A 45Q, based on what Ryan told us about the LLO experience.  With this sensor we can keep the loops closed throughout the whole CARM offset reduction without flipping the sign. 
• We reduced the PSL power to 2.8 Watts after locking DRMI and transitioning to TR_CARM. (this is added to the guardian)
• We let the guardian take us to the "10PM" state
• We added a boost to the REFL BIAS path, (FM2) which has a z2:p0.01. 
• We adjusted the TR_CARM offset (to about -34 or -36) to get the offset in TR_REFLAIR input to -0.08
• We ramped on TR_REFL with 8 in the input matrix and 0 in TR_CARM.
• We reduced the TR_REFL offset to zero
• in this situation we had large angular fluctuations, and didn't hold the lock very long.  Our arm buildups were around 800 times the single arm power, and REFL was less than 10%

Our next steps will be to check the loop gains before we try turning off the refl offset, and trying to increase the DHARD WFS bandwidth.  

We also toggled the noise eater tonight (we thought it might have been oscillating but this probably wasn't the case). We also copied the invP2P and Y2Y filters from the drivealign matrix into the opLev servos so that we can work on the DHARD WFS loops independent of these filters.  

Lock loss times: all Feb 4th UTC 

4:14:00

5:00:00

7:09:00

J. Kissel

More interesting data on the HEPI Pump Servo. Looking to ID the response of the HEPI Differential Pressure "Plant," i.e. from the control drive output to differential (supply - return) pressure change, I turned OFF the servo and put small steps in the control output of varying sizes (see pg 1 of 2015-02-03_H1HPI_PumpServo_SysID.pdf). First linearly increasing step amplitudes to determine the DC gain (see pgs 2 and 3). Then, to determine the frequency response, I put in many steps of the same size to fit the impulse response (see pg 4).

The results: As it stands, the HEPI pump servo plant can be well-approximated by a single pole at 24 +/- 1 [mHz] and a DC gain of 0.0546 [PSI/ct]. Note, E1100508 suggests that the plant is a single pole a 7 [mHz], with a DC gain of 0.087 [PSI/ct]. Looks like not.

With this information, and the current PID settings of (35,0.45,0) respectively, I can predict the current open loop gain (see pg 5). I model a UGF of 39 [mHz], with a suppression of 0.37 @ 10 [mHz], 0.2 @ 1 [mHz], below which the 1/f integrator kicks in. Note, E1100508 suggests using PID params of (20, 0.07, 0), which would result in even lower a UGF and less suppression.

With such a simple plant, it's really tough to find PID parameters that aren't stable, so I also show a toy set of parameters with much higher values, (P,I,D) = (300,30,0), where the integrator dominates. With these parameters, we get a UGF of 390 [mHz], with suppression of 0.24 @ 100 [mHz], 0.035 @ 10 [mHz], and so on.

Why not increase the UGF to infinity? 
Because there're worries out there that above a few [Hz], poorly-matched impedance, transmission-line-like effects take over the frequency response, which may cause sharp, phase-full features in the plant that are not characterized by a simple pole.

Why does this not-at-all match what's measured when comparing Closed vs. Open. vs. No Sensor ASD spectrum?
(see 2015-01-27_H1HPI_DifferentialPressure_Open_v_ClosedLoop_Comp.pdf, and 2015-02-02_H1HPI_PumpServo_ADCNoiseCharacterization_DiffASD.pdf, which is not new data, but copied to this aLOG for convenience)
Open vs. Closed loop ASDs show that there is suppression of 0.1 @ 10 [mHz], not the modeled 0.37 @ 10 [mHz]. Further, the measured spectra shows some gain peaking of a factor of 2, where the model predicts no region where the suppression is above unity. It really does seem like the ASD behavior of the signal is totally disconnected from the time series behavior of these sensors. I really hope this whole saga isn't some false alarm from EPICs vs DTT nonsense...

-----
Raw Data lives here:
/ligo/svncommon/SeiSVN/seismic/HEPI/H1/Common/2015-02-03_H1HPI_PumpServo_StepResponse.mat

Data Processing Script lives here:
/ligo/svncommon/SeiSVN/seismic/HEPI/H1/Common/H1HPI_PumpServo_StepResponse_20150203.m

As it happened the new als models contain another experimental feature: An align/misalign button for the input beam steering. This feature was added at the end of the integration module. The aim is to have separate values for the misaligned and aligned state. The alignment values are the output bias of the integrators. This allows for instantaneous and glitch-free off-loading as well as a single button misalignment. The misaligned state can either be a fixed value or a value which is added to the aligned value. An additional calibration gain has been added to the output to make sure the alignment values are in physical units. All state changes are done with a smooth ramping process.

All integrators have been updated to include a ramp time.

Before today's work the models running on h1iscex, h1iscey were:

After the split the models now are:

teal = model not changed

New PEM = OLD PEM + OLD CAL

NEW ALS = ALS component of old ISC (inherrits old ISC core and dcuids)

NEW ISC = old ISC minus ALS (uses old CAL core and brand new dcuids)

Spliting the End Station ISC Models Into Two

Daniel, Jim, Dave:

WP5034. The problem: end station isc models are running long, so their RFM IPC to the corner station do not make it in time. The solution: split the ISC model up into ALS and ISC, with the latter running faster and able to send RFM IPC to the corner in the allocated time (60uS).

Because the h1iscex,ey computers did not have any spare cores (iop, pem, isc, odc, cal) for now we added CAL to PEM to free up a core. Hopefully a better long term solution is to combine isc and odc.

Daniel had done a lot of early legwork getting the models into shape. He hand edited the H1.ipc file to change the source model name for channels moving from ISC to the new ALS models. Daniel also handled the filter module files.

We identified all models which receive IPC channels (including Dolphin) from the new ISC and ALS models. These were also recompiled and restarted.

First thing this morning we moved the new H1.ipc file into place and did a round of make and make-install on the related models. The testpoint.par file needed editing during the "make install" process due to the model-dcuid change for the isc models.

The rtsystab file was modified for the new model layout in the end station isc front end.

Then all the related models were stopped:

h1lsc, h1asc, h1susetmx, h1susetmy, h1hpietmx, h1hpietmy, h1pemex, h1iscex, h1odcx, h1calex, h1pemey, h1iscey, h1odcy, h1caley

The h1iopiscex and h1iopiscey were restarted. We saw an awgtpman autostart problem with these models.

The end station models were restarted (h1pemex, h1iscex, h1odcx, h1alsex, h1pemey, h1iscey, h1odcy, h1alsey). We had to play around with the safe.snap files for the ISC and ALS models to get them to startup.

The receiving models were restarted (h1lsc, h1asc, h1susetmx, h1susetmy, h1hpietmx, h1hpietmy)

The IPC from the end station ISC models to the LSC are now without any errors. The ALS model still has some IPC to the LSC and this retains its error rate (this model was not substantially sped up).

The DAQ master file was reconfigured for the new model layout, and H1EDCU_DAQ.ini was resynced.

I checked the DAQ data for the PEM and found it was corrupted. This was tracked to the change of the ADC part name in the model when PEM and CAL were combined, and we forgot to remap the bus selector parts attached to the ADC. This was fixed, there is a two hour gap in PEM data.

CDS OVERVIEW MEDM

Dave:

The H1CDS_STATE_WORD_CUSTOM.adl overview MEDM screen was updated:

• model shuffle in end station ISC front ends
• addition of CFC (configuration file change) bit. A BLUE bit like the overflow.
• addition of the CONLOG section