model restarts logged for Tue 18/Nov/2014
2014_11_18 01:41 h1fw0
2014_11_18 10:51 h1isiham4
2014_11_18 10:51 h1isiham5
2014_11_18 10:56 h1sussr2
2014_11_18 10:58 h1sussr3
2014_11_18 10:58 h1sussrm
2014_11_18 11:01 h1hpiitmy
2014_11_18 11:27 h1broadcast0
2014_11_18 11:27 h1dc0
2014_11_18 11:27 h1fw1
2014_11_18 11:27 h1nds0
2014_11_18 11:27 h1nds1
2014_11_18 11:29 h1fw0
2014_11_18 11:54 h1psliss
2014_11_18 11:57 h1broadcast0
2014_11_18 11:57 h1dc0
2014_11_18 11:57 h1fw0
2014_11_18 11:57 h1fw1
2014_11_18 11:57 h1nds0
2014_11_18 11:57 h1nds1
2014_11_18 11:58 h1nds1
one unexpected restart. Maintenance day. Ham4,5 ISI and SUS work, with associated DAQ restart. PSL ISS work with associated DAQ restart. Double restart of h1nds1?
Alexa, Dan, Nic, Sheila, Evan
Tonight we made some improvements to our automation, and we reduced the CARM offset with DRMI locked on 3F.
I have attached DRMI spectra on 1f and 3f with the arms off resonance (1kHz green COMM offset). The first plot is the DRMI 1f configuration; Kiwamu pointed out that one can see the periscope resonances that are present in ALS COMM noise appear in the DRMI signals. The second attachment is of the DRMI 3f configuration, and these noise features are less prominent.
Relevant UTC times:
Great progress! About the ASC, L1 uses REFL_B_45Q -> SRM with bandwidth of 100 mHz ( LLO 13513 ) in the first part of the locking sequence, as AS_RF36_I for SRM didn't work well ( LL0 13358 ). Here I see that you are using AS_RF36_I for SRM ASC in DRMI without arms...just checking.
Thanks for the information Lisa.
Also, for the record, here are several times that we lost the arm locks last night without a known reason (at least, we didn't think we were doing anything stupid at the time that would have caused the lock loss). All times are UTC, Nov 19, and the lock loss should be several seconds before the time I wrote down.
2:36:27, 3:06:34, 5:58:43, 6:12, 6:25:08, 6:51:07, 7:40:50
Here is the sensing matrix of DRMI3f with 7 nm (= 1000 Hzgreen) CARM offset. I extracted this using the three calibration lines that were injected during the locking period: 131.7 Hz, 6000 ct into PR2; 183.7 Hz, 1000 ct into BS; and 152.9 Hz, 6000 ct into SR2.
In the following table, the first number in each pair is the magnitude (in ct/ct), and the second is the phase.
PR2 | BS | SR2 | |
---|---|---|---|
RF27 | 7.6(1.2), 3.4(3)° | 0.29(6), 151.3(7.8)° | 0.07(3), -70(110)° |
RF135 | 12.3(2.0), 139.7(4.5)° | 0.7(3), -84(35)° | 1.6(4), 6(14)° |
J. Kissel Interested to see how the projected ISI channels compared with Kiwamu's assessment of PR3 (see LHO aLOG 15048), I've plotted (a) The input noise budget for the Suspension Point Longitudinal Motion, and (b) The Transfer function between suspension point and L, P and Y of the optic using whatever local sensor was available. for SRM, SR2, and SR3. Remember that the damping loops for these suspensions is still the "hand-tuned" dumb velocity damping. Also note that SR3, Oplev to M2 Pitch damping is ON for this measurement. A couple of conclusions: From the Susp. Point L budget -- (1) For all three SUS, with the current HAM ISI blend design, we're limited by the HAM4 / HAM5 Y motion at just about all frequencies. Where there has been effort to carve out performance at 1-2 [Hz] in Y in the ISI, RX of the ISI limits the performance. (2) Some how, even though RZ appears WELL below the limiting noise source for L, it's still somehow ~70 to 80% coherent between 0.1 and 0.6 [Hz]. Huh?? From the Susp. Point L to Optic TFs -- (4) Susp. Point Longitudinal is the dominant contributor to Pitch at the optic, by a long shot. (5) The OSEMs, which are relative motion sensors between the cage and suspension, fall off in response below the SUS's first resonance as 1/f^2 as expected. (6) Perhaps unexpectedly, the OSEMs are still *coherent* below the first SUS resonance, down to quite low frequencies. (7) Susp. Point L, some how contributes a great deal of motion to Yaw as well as Pitch between 0.7 [Hz] and 1.5 [Hz], amplifying input motion as much as a factor of ~100. (8) The difference in damping between SRM and SR2 seems to have significant affect on the Susp. L to Optic L TF at the first and second resonances (0.7 [Hz] and 1.53 [Hz] for the HSTS). Recall that for angle, SR3 contributes the most to *cavity* angular fluctuations.
K. Venkateswara
After the problems with BRS last week (15005), it was left off for the last ~five days. I tested the damper controller and it looked like the issue with vibration driving the BRS had cropped up again (14596). It wasn't clear why this problem had reappeared but since the foam sheet had worked previously, I went back to that configuration. With the foam sheet under it, the damper appears to be working fine. However another issue with it is that the zero position of the turn-table appears to change, seemingly randomly. It is possible that the stepper motor is occasionally getting stuck. As it's not servo'd this may explain the drift in the zero position. For the moment, I think it requires periodic checking to ensure its zero hasn't changed too much. If it changes by 90 degrees, it can drive the BRS in a positive feedback loop like last week. A servo loop is a better long term solution.
I have also modified the following filters:
1. BRS transfer function inversion filter to correctly account for the imaginary zero at 7.3 mHz (due to the finite d). I was using pairQ(7.3e-3,3) before whereas pair(7.3e-3,0) should be the right choice.
2. The tilt-subtraction filter has also been changed - the high-pass filter (2-pole) has been changed from 2.5 mhz to 4.3 mHz to correctly compensate for the T240 resonance.
The attached pdfs show the ASD for the BRS and the ground T240 in angle and displacement.
J. Warner, J. Kissel, K. Venkateswara
After improved modelling of sensor correction (SC), thanks to Rich M. (615, 623), we re-attempted SC along X (and along Z). X sensor correction was to stage 1 ISI, while Z was on HEPI. Unlike our previous attempt (14896), we used Rich's SC_filter described previously in 14570.
The first pdf shows the ASD from before SC for X and Z. Stage 1 T240, CPS and ground motion is shown and the coherence between them. The second shows the platform motions after SC. The third pdf shows a comparison between the configurations as measured by the T240 showing the expected 2-5 factor improvement between 0.1 to 0.5 Hz. It also shows an improvement below that which is more surprising (maybe from Z SC?). There is no visible re-injection of noise (factor of ~2 is epxected between 20-40 mHz), because we are probably dominated by pre-existing noise which is larger. More testing will be done tomorrow. The OpLevs are currently mis-aligned so I can't see the effect of SC on them.
Note that the we did not use tilt-subtraction at the moment because wind-speeds were practically zero. We will test the tilt-subtraction when winds pick up a bit.
Once again, if this appears to be adding noise instead of helping, the comissioners can turn it off from the ETMX ISI medm screen as before.
Looks like the X arm is better behaved this time. I've attached ASD of the ALS-X control signal and the Stage 1 CPSs for ETMX and ITMX from tonight's locking.
This morning, I tried using the tilt-subtracted ground super-sensor for sensor correction along X, rather than the plain ground sensor. The attached pdf shows the Ground Sensor (T240), the super-sensor, Stage 1 T240 X, BRS RY OUT * g/w^2 and the Stage 1 CPS. Please note that the CPS data is after the sensor correction (it is input to the blend filters), hence it is should be less than the ground motion above ~100 mHz.
The plot shows that in non-windy periods, the super-sensor is not much noisier than the regular ground sensor and tilt-subtracted sensor correction is therefore about the same as regular sensor correction.
Gabriele, Jeff, Dave
Two sets of DAQ restarts today:
11:27 Resync INI files for SUS changes made by Jeff (HAM4,5)
11:57 Resync INI file for h1psliss model change, made by Gabriele
No Beckhoff INI changes seen over the past week.
Jamie, Dave [WP4947]
Today we reconfigured and restarted all the guardians to ensure that no log files will be deleted.
The process involved running guardctrl create --all
and then stopping and restarting the entire guardian supervision. The guardian nodes did not restart, which Jamie tracked down to default settings after the re-creation. He started all the nodes, but one of the 71 nodes did not restart cleanly (SUS_MC2). A subsequent restart of this node was successful, Jamie is investigating why this happened.
We will most probably reboot the guardian machine next week for OS security patching and at that time check for any node failing to start correctly. Today we just patched bash
.
We will keep WP 4947 open to cover next weeks patching.
New SR3 offset: [452.9, -155.3].
There could be +-120-ish measurement error for YAW due to difficulty in finding the PR2 baffle right edge, so later if somebody gets suspicious about the clipping finer YAW scan of SR3 might be a good idea. This problem is not present for PIT.
New SR2 offset: [2800, 800].
Tolerance is +-100, but the center value strongly depends on the SR3 offset.
Since Doug is not available for finding the SR3 oplev beam with new offset, and since we use SR3 oplev for damping, we reverted SR3 and SR2 back to the original angle.
Tomorrow morning SR3 oplev will be done with Doug.
Plots will be posted later.
SR2 [2963.7, 2728.0]. SR3 [430.3, 142.6].
Centered AS_C using SR2 offset: [2917. 7, 2794.0].
At this point ASC_SUM was [1576.29, 1576.87] (measured twice, each is 10sec average number).
Position 1: [3042.9, -438.4].
Position 2: [-2137.1, -408.0].
Center = (Pos1+Pos2)/2 = [452.9, -423.2].
Then moved the beam to the right edge.
Position 3: [452.9, -1248.4+-100]. Barely touching.
Position 4: [452.9, -1848.4+-500]. Totally blocked.
For whatever reason YAW is much more ambigous than PIT to my eyes, and right edge is more difficult than top and bottom.
Right = (pos3+pos4)/2 = [452.9, -1548.4+-510].
Center-Right = 1125.2+-510 in the slider counts. This is supposed to be 36.75mm.
SR3-SR2-SRM angle is 1.67deg, and the baffle-SR2 distance seems like about 46cm (eyeballing HAM4 systems drawing), so the beam distance at the baffle is 17.5mm.
New beam position = 17.5mm/2 =8.75mm to the left of the center.
Y=-423.2 + 8.75mm/36.75mm * (1125.2+-510) = -155.3 +- 120;
NEW SR3 slider = [452.9, -155.3+-120];
At this point SR2 was moved to [2708.7, 814.0] to center AS_C, and the SUM was found to be [1596.99, 1597.84, 1596.48] (three measurements), this is about 1.3% increase from the initial number (but note below about the interference pattern caused by either some etalon effeft of a ghost beam from somewhere).
Scanned SR2 in YAW, then in PIT, to find the Faraday edge while centering AS_C using Pico.
Today I made a finer scan than previously done (https://alog.ligo-wa.caltech.edu/aLOG/index.php?callRep=15023) and what I originally thought to be a ghost beam looked more like an etalon type interference that mostly depend on the beam angle on AS_C. It was mostly in YAW but you can also see it in PIT, and the pattern is very repeatable.
Anyway, my objective here is just to place the beam at the center of the Faraday aperture, and I chose this:
New SR2 slider = [2800, 800].
The peak-to-valley in YAW data is as large as 1.5% or so. Does this mean that SR3 scan before/after comparison is useless? No.
During SR3 scan, the beam was shifted by 300 counts in YAW, or about 10mm on SR2. The beam pointing on AS_C was fixed using SR2, so the beam angle on AS_C changed by about 10mm/18m or so, i.e. about 600urad or so.
OTOH, the full scale of the SR2 YAW scan corresponds to the Faraday aperture of 20mm, and that's roughly the beam shift on the pico. The beam position on AS_C was fixed using pico, and pico-AS_C distance is about 14 inches, so the beam angle change over the entire SR2 YAW scan is 20mm/14" = 60mrad or so. This is three orders of magnitude larger than SR3 scan angle change.
If we replotted it as the function of beam angle on AS_C (which I didn't), and put both the SR2 scan and SR3 scan data on the same plot, two data points representing the before/after SR3 scan would be basically on one vertical line in the plot. If this is indeed an etalon type thing on the diode surface, basically SR3 before/after the beam would see the same interference. That's my theory anyway.
Patrick, Dave
The conlog reporting of frequently changing EPICS channels has discovered several code issues in the past week. Conlog reports hourly those channels which have logged 500 or more changes in the previous hour. I have written a python script to concatinate 24 hourly reports into a daily report, which I'll post in the alog.
Below is the log from yesterday (Monday 11/17). We discovered a guardian node which was setting the end station SUS L1_LOCK_L filters RSET (clearing history) at 16Hz. This was fixed between 1pm and 2pm.
The per-second number is calculated as total/(hours-active * 3600). Numbers in the 16 range are most probably front end or guardian related, higher than 16 most probably Beckhoff or scripts.
11/17/2014 hs total per-sec
H1:SUS-ETMX_L1_LOCK_L_RSET 14 751286 14.9
H1:SUS-ETMY_L1_LOCK_L_RSET 14 751286 14.9
H1:ALS-C_COMM_VCO_TUNEOFS 02 90021 12.5
H1:ALS-Y_FIBR_LOCK_TEMPERATURECONTROLS_ON 06 62062 2.9
H1:ALS-Y_CAM_ITM_PIT_POS 24 58548 0.7
H1:ALS-Y_CAM_ITM_YAW_POS 24 58548 0.7
H1:ALS-Y_CAM_ITM_SUM 24 58539 0.7
H1:GRD-ALS_YARM_USERMSG 05 16658 0.9
H1:ALS-X_REFL_SERVO_IN1EN 05 11208 0.6
H1:SUS-IM4_M1_OPTICALIGN_Y_OFFSET 03 6052 0.6
H1:SUS-IM4_M1_OPTICALIGN_P_OFFSET 02 3136 0.4
H1:GRD-ALS_XARM_STATUS 02 3082 0.4
H1:GRD-ALS_COMM_USERMSG 03 1781 0.2
H1:SYS-MOTION_C_PICO_A_CURRENT_DRIVE 02 1516 0.2
H1:GRD-ALS_XARM_TARGET_S 01 632 0.2
H1:GRD-ALS_XARM_STATE_S 01 550 0.2
H1:SUS-PRM_M1_OPTICALIGN_P_OFFSET 01 504 0.1
Some of the GRD channel changes are likely reflective of actual changes in the system. It's not clear to me that conlog should be monitoring the following guardian channels:
_STATUS _GRDMSG _USERMSG _NOTIFICATION _STATE_S _STATE_N _TARGET_S _TARGET_N _OK
None of those channels are set by users, so they may change as fast as the system changes.
I've restarted the web snapshot tool for the vacuum screens to incorporate updates by G. Moreno.
LVEA: Laser Hazard Observation Bit: Undisturbed, Switched to Commissioning 06:45 Karen – Cleaning in the LVEA 08:24 Krishna – End-X to work on the BRS system 08:30 Karen – Out of the LVEA 08:35 Filiberto & Aaron – going to End-Y and End-X to switch power for PEM and PCal 08:46 Karen – Going to End-Y 08:48 Mitch & Jeremy – Working in west bay on ACB assembly 09:50 Dave – Restarting Guardian 09:55 Joe – Going into the LVEA to check fire extinguishers and emergency lights 10:25 Cyrus – Going to end-y to reboot computers 10:30 Keita – Taking a tour through the LVEA 10:33 Dick – Checking electronics at ISC Rack #1 10:41 Joe – Out of the LVEA 10:50 Praxair - N2 delivery to CP8 11:01 Karen – Back from End-Y 11:08 Keita – Out of the LVEA 11:35 Praxair – N2 delivery to CP4 12:00 Dave & Ops – DAQ restart 12:25 Filiberto & Aaron – Back from the end stations 13:00 Dick – Out of the LVEA 13:15 Betsy – Working in LVEA west bay 13:35 Mitch & Jeremy – Working in LVEA west bay on ACB assembly 14:24 Richard – Escorting fire department to Mid-Y 14:37 Kyle – In LVEA checking vacuum equipment 14:48 Kyle – Out of the LVEA 14:52 Andres – Going to LVEA west bay 14:55 North Coast – Delivering parts for Richard
Here is an informational post on a cool tool that I’ve found.
The tool is called Markdown here. It is a way to use a common rich text markup language and use it to make rich text in many web forms. It is (mostly) compatible with the LIGO a-log.
The steps to use it are:
Some of the features that you can use are:
It will accept latex formulae:
class INIT(GuardState):
request = True
def main(self):
log("initializing subordinate nodes...")
nodes.set_managed()
def run(self):
return True
optic | bias | how i feel |
---|---|---|
ETMX | 400cts |
|
PR2 | 5cts |
|
ITMY | 100V | tired |
As you are making your post, you will want to preview what it looks like, but if you want to edit, you must always change back to plain text before you edit, or you may lose changes.
By default, the return
key in the alog makes a double line break. Markdown here works a lot better with single line breaks. You can make single line breaks with shift+return
.
Because most browsers can’t display math fonts by default, the latex formulae are actually images, which is a bit inelegant, but it works. You must also explicitly enable latex formulae in the settings before it will work.
As a bonus, you can also use it with gmail (and thunderbird)! So you can put math in your emails as well.
Good luck!
WARNING: equations in markdown actually utilize a (possibly deprecated!?) online service. This means that the produced equations are actually links to images hosted on a third-party web site. If that site goes away, so do the equation images. Your log post my not look as intended in that eventuality.
Here is a collection of suspicious CPS trips on ITMX. This is a problem only on this chamber, which has just cropped up in the last few weeks. It needs to be investigated.
another example
Still there, still a problem....
I made a few plots today. The spectrum of the CPS right before and right after the trip, and the zoom-in time series plot around the time of the trip. I notice that the time that the CPS signal goes down does not match the GPS time indicated the trip exactly (off by a few hundred milliseconds). While making the spectrum I also notice the peak near 4Hz in the "beforetrips" spectrum plot. So I went and look at the LHO summary page and found that there's a small gaussian-looking bump around 4Hz that seems to appear everyday. Probably not very important but just wanted to point that out. Also, please note that V2, H2, and H1 signals are almost perfectly overlapped (that's why you only see two colors). I'll start looking into other related channels that *should* have seen the signals. Although I believe this might be an electronics issue.