(Daniel, Kiwamu, Chris, Stefan) - Using PR3 we pointed the green beam to the center of the septum view port. some pointing references for PR3: PIT: -145, Yaw: 125 Center of septum view port, we left it there PIT clips at -85 and -206 Yaw clips at +75 and +198 - Kiwamu moved the top periscope mirror in HAM1 up until the green beam was centered on it. The periscope yaw position agreed well with the center of view port. He then guided both the green ALS beam and the POB beam (actually IR, but we used green as alignment proxy) to ISCT1. Note that the POB beam does not yet have all its hardware, but we suspect it might be useful later. We dumped all stray beams on ISCT1, and put the green beam on H1:ALS-C_TRY_A_DC to have a reference. - For the red beam - unlike yesterday -we were not able to get IM4 TRANS pitch to zero (using a MC move), possibly due to falling off the WFS sensors. For now we ignored this. - We then realigned the red beam following the same procedure as yesterday. (PR3/PR2 walk keeping fringes, putting PR3 to its desired spot. PR2/IM4 walk to optimize transmitted fringes). This actually gave us a signal in the POB quads (H1:ASC-POP_A_SUM_OUT and H1:ASC-POP_B_SUM_OUT) - Finally we also hunted and found the PRM alignment. Power recycling fringes with a power gain of about 3 are visible on both POB quadrant diodes and as stray light on the ITM cage. - The attached alignment snapshot reflects the fully aligned power recycling cavity (incl PRM).
The power of the green beam on ISCT1 was measured to be 2.8 mW.
I found the MC alignment offsets off and a measurement in progress when I got in, but I have no idea who is measuring, as I am the only one one site. Please call the control room. Stefan
I was measuring consecutively MC1/MC2/MC3 M2 to M2 and M3 to M3 transfer functions over the week end. The script can be killed by closing matlab windows on workstation 2, and overwriting the current excitation with awggui.
I will make sure to post an aLog next time.
Sorry, Stefan. Arnaud told me in advance that he wanted to do this and I forgot to pass the word along.
(Chris, Kiwamu, Mike L., Daniel, Stefan) We entered HAM1 today, but did not find any green in it. Thus we started to look for some green in HAM2 and HAM3 through the view ports. By far the most useful port turned out to be the view port on the terminating flange of the MC tube - it allows for a clear view of the HAM2 baffle. With some beam wiggling it was easy to establish an alignment that let the green beam bypass the HAM2 baffle and travel all the way to the HAM1 periscope. (We did not move the BS, as BS and PR3 are very degenerate, and for the X-arm we won't have the BS.) Unfortunately, while the green beam comes down the periscope of HAM1, it does not make it through the HAM1 view port - we can see it hit the vacuum tank. So we will have to go into HAM1 to realign the optics. This however can now be done on the PSL side of HAM1, eliminating any risk of accidentally damaging the septum view ports. After we had established the PR3 (& BS) alignment that gets the green beam out to HAM1, we again found the red fringes in the arm, using the following procedure: Since we knew an alignment that produced fringes, we beam-walked PR3/PR2 from that location to the PR3 alignment that gets the green beam out, while maintaining arm fringes with PR2. Next we used a IM4/PR2 beam walk to maximize the arm transmitted fringes. Note that this did pull us off the ASC-POB QPD's.... not sure what to make out of this. Below is a snapshot of both the initial in-air alignment and the current alignment that gets the green beam to HAM1 and red arm flashes.
Attached are plots of dust counts requested from 5 PM June 6 to 5 PM June 7. Both the dust monitor at location 14 in the LVEA (H2 PSL enclosure) and the dust monitor at location 16 in the LVEA (H1 PSL anteroom) are indicating calibration failures.
The latest version of the HAM-ISI master model was updated from the SVN. I started compiling it. make worked, but make install- did not. This is due to a part that the new HAM-ISI model expects from the BSC-ISI one. We did not expect such dependancy and soppose it is a copy/paste issue (dependancies can get tricky under simulink).
Here is the error message returned by make install-:
ERROR: For part: "isi2stagemaster/ISI2STAGE/ST1/SENSCOR/X_BLRMS"
Could not find the proper library reference.
Your model may be referencing a different source model than what is in the current library path.
Both ISIs remain actively controlled
Today I estimated the position of the beam spot on the input mode cleaner mirrors, following the procedure used in LLO alog 5010. The results:
Coil drive unbalance (%) |
Position Shift of Node (mm) |
|
MC1P | -4.0 | -1.5 |
MC1Y | 1.7 | 0.6 |
MC2P | -5.9 | -2.2 |
MC2Y | -4.3 | 1.6 |
MC3P | -4.1 | 1.5 |
MC3Y | -7.9 | 3.0 |
I couldn't find documentation on how to get to coil drive imbalance from P2L/Y2L gain, so I wrote up a short document in TeX describing the method to make reproducing these results relatively straightforward.
With the HAM1 East Door removed and help from MikeL & StefanB, we checked the level/elevation of the Optical Table. As compared to the elevation measured 1 Oct 2012, the Table is still very close to where it was then, within 0.2mm; caveat: I am using a different elevation reference and we were not able to reach all around the table for a good spacial sampling. The level however was off: the North Center area of the table was lowest with the Southeast corner higher by 2.3mm. This makes sense as mass has been added on the North and West sides since it was level +-0.1mm on 1 Oct. Also to consider, HEPI is floating with fluid flowing. Before leveling the Optical Table, we will survey the Support Table and level it with HEPI.
Fly forklift over beamtube-Clean at HAM1x2 (LVEA)- Mark and Terry S. Soft-closing GV18 at End Y – Kyle Work on BSC9 HEPI Actuators at End X – Hugh & SEI Work (floor repair) at End X/LVEA – Craftsman Floor Testing!(Transfer Functions on MC2) at HAM2-LVEA – Arnaud P. Work on BSC6 viewport at End Y – Corey Dust monitor work at End X – Patrick Opening GV18 at End Y – Kyle Shutter out PSL main beam (LVEA) – Michael L. LVEA Transitioned to Laser Hazard – Michael R. HAM1 E door removal (LVEA) – Apollo
Installed the 2nd Light Pipe for the H2 ALS EY Table. This is for the IR path. (not sure why ALOG rotates attached image)
Similar to the design efforts with the QUAD and BSFM, I designed and implemented a set of "Level 2" damping filters in which - All DOFs (except Roll) meet or beat their 10 [Hz] requirements. (Details about Roll below.) - High-frequency modes are better damped, while still maintaining the majority of the low-frequency damping. The lowest frequency mode in all DOFs (which will have highest displacement amplitude because the ISI's isolation is less) are damped to the same Q, if not even a little less. - Over all gain is reduced, such that noise between the resonant modes and out-of-band is less. This new configuration has been appropriately captured and stored in the userapps SVN. Enjoy! Design Details -------------- As with all the other suspensions, the top-mass BOSEM sensor noise filtered through the damping loops is the dominate noise source above ~5 [Hz]. Thus the loop designs are primarily focused on modifying each loop such that they collectively meet their displacement noise requirements. The requirements on the displacement noise are most stringent on Pitch and Yaw of the optical bench for the TMTS, which according to Fig 18 of E1100537 need to hit "a few" x 10^-15 [m/rtHz] at ~10 [Hz]. The remaining degrees of freedom have much more loose requirements BUT because the top-mass blades are misaligned with respect to the Euler control basis like the QUAD, the degrees of freedom are dreadfully cross-coupled at high frequency. (For supporting imagery, check out Mark's mode shape page.) For example, in order to meet the Pitch requirements at 10 Hz, one must consider the performance of the Longitudinal (obviously), and Transverse. In fact, Transverse is cross-coupled to Pitch, Yaw, and Roll -- the latter so much so that the Transverse residual seismic and top-mass sensor noise dominate the Roll of the optical bench by 1 to 2 orders of magnitude. The problem with this cross-coupling is that Transverse has the highest frequency resonant mode, at 4.2 Hz. Typically (i.e. in the QUAD and BSFM), this highest Transverse mode couples well to Roll, which in those cases have less stringent requirements. This means you can squash the mode in Roll, sacrificing some sensor noise contribution there, leaving little left to do in Transverse. In the case of the TMTS, the Roll requirements are more stringent AND the 4.2 Hz mode doesn't couple well to Roll, so one can't get enough loop gain to damp it. So. In order to get *some* damping on this mode, and retain a decent Q on the lower modes, it is difficult-at-best (assuming I stick to the relatively simple, IIR-only, loop design) to roll off the loop gain fast enough to reduce the sensor noise contribution to the 10 [Hz] bench motion. With my design efforts -- involving a 4th order elliptic (similar to the BSFM V design) as well as an extra "phase booster," real, zero/pole pair -- I was able to reduce the Transverse contribution to Pitch and Yaw to below the requirements at 10 [Hz], but Roll is still at ~1e-14 [m/rtHz] at 10 [Hz], but meets the requirement by 16 [Hz]. For a summary comparison between the previous filters and the current filters, check out dampingfilters_comparison_2013-03-13vs2013-06-06.pdf. If you're interested in the details of the new design, and plots backing up the above design description and problems, check out the attachment dampingfilters_TMTS_20130606.pdf shows all of the usual design figures of merit. (The old design is shown in dampingfilters_TMTS_20130313.pdf). A quick, confirmation measurement that the control signals (which, as the model says, should be dominated by sensor noise above 5 [Hz]) have reduced as much as expected in the 10 [Hz] region and above for the most interesting degrees of freedom for the TMTS. Configuration ------- For all degrees of freedom, FMs 1 ("rolloff_*"),2 ("boost_*"),5 ("norm*"), and 10 (ellip_*) should be engaged. As with the BSFM design, the overall gains of the loop have been folded into the boost_* filter, so that all the EPICs gains are an easy-to-remember -1. Note that this deviates from traditional SUS gains; this is a new era of not-just-velocity-damping-anymore. Hence, the new EPICs gains are: L = T = V = R = P = Y = -1. This new configuration has been captured with an updated safe.snap, ${userapps}/release/sus/h1/burtfiles/h1sustmsy_safe.snap and the new foton file has also been committed here: ${userapps}/release/sus/h1/filterfiles/H1SUSTMSY.txt Scripts, Functions, and Templates ------- The scripts used design the loops and generate these plots can be found here: ${SusSVN}/sus/trunk/TMTS/Common/FilterDesign/ design_damping_TMTS_20130606.m compare_tmts_dampfilter_design.m The former calls the FOM producing functions ${SusSVN}/sus/trunk/TMTS/Common/FilterDesign/ plottmtsdampingcontroldesign.m plottmtsactuatornoise.m The template to compare the control signal ASD lives here: ${SusSVN}/sus/trunk/TMTS/H1/TMSY/SAGM1/Data 2013-06-07_1753_H1SUSTMSY_M1_DAMPOUT_Spectra.xml
Hugh, Hugo,
The Local Static Offset Test* was performed yesterday on HAM1-HEPI. Corner #2 appeared to be responding less than it should have. (see table 1 of attachment)
We found a contacting point on HAM1-HEPI's pier #2: The Crossbeam Foot was contacting with the Back Caging Brace. (see figures 1 and 2 of attachment)
We loosened the Back Caging Brace, and adjusted its position to leave a cable-tie-wide clearance with the Crossbeam Foot. Other corners have at least this amount of clearance. Corner #3 was a bit tight though.
Those adjustments seems to have solved the problem per the latest Local Static Offset Test taken yesterday evening. (see table 2 of attachment).
We will be doing a Range of Motion Test** as soon as we have a chance to confirm that there is no contact point throughout the whole range of motion of HEPI.
*: Drive one actuator (5000cts), and record the local readouts to check for unexpected cross-couplings, and potential contact-points or rubbing.
**: Drive the HEPI through its full range and make sure that range is not limited.
THE frequency comparator was not working last night, because the als laser noise eater is oscillating. This can be seen by a large peak in the beat note signal at 1MHz (-8 dBm on the +13 dB preamp output). With the noise eater oscillating, the noise eater monitor is at 3.14 V. Turning the noise eater off fixes the problem, I am going to leave it off.
(Kiwamu, Chris, Stefan) Morning: ======== Created the H1IFO_ALIGN medm screen and installed BS Face camera (with Richard) Afternoon: ========== First we re-established the IM4 trans reference that Keita established on May 22 (alog entry 6472). This was done my locking the IMC, moving the MC3 pitch slowly while input beam and MC were following, until we hit IM4 TRANS again. We then used the IMC WFS relief script (/opt/rtcds/userapps/release/ioo/h1/scripts/imc/mcwfsrelieve) to park the mode cleaner and input beam in this new orientation. (Note: this reliefs the offsets into the actuator offset fields, H1:IMC-MC1_PIT_OUTMON etc., NOT the MC alignment sliders (we should fix that tomorrow, see below for the current offsets) Next, after thinking way too hard on how to proceed, we moved one slider (PR3 yaw, H1:SUS-PR3_M1_OPTICALIGN_Y_OFFSET) and saw the beam on the BS cage. Centering it roughly on the BS made it visible on the ITM cage. The beam was moving too much, so we repeated yesterday's trick: increase the M0 damping gains... it worked again and quieted the beam motion down. (The old and new gains are below.) With that we pointed the beam roughly on the middle of the ITM, and... saw fringes on both monitor and transmitted QPD. Since up to that point we had only moved one slider (H1:SUS-PR3_M1_OPTICALIGN_Y_OFFSET), nobody actually believed what we saw. But after misaligning the green beam the fringes were still there, and only went away when we moved the red beam... Set up the anti-whitening filters for the transmission monitor at the end. Next we wanted to go look for the green beam at ISCT1, but unfortunately the PLL loop broke (see Sheila's log). So that's for tomorrow. Attached images: =============== 1) Alignment settings when we stared 2) Alignment settings after mode cleaner move (!Caution: additional nonzero MCWFS offsets, see below!) 3) Alignment setting when we got fringes (!Caution: additional nonzero MCWFS offsets, see below!) 4) Fringes on the trans mon! Settings: ========= Old PR2 and PR3 damping gains: H1:SUS-PR2_M1_DAMP_L_GAIN = -1.55 H1:SUS-PR2_M1_DAMP_T_GAIN = -2 H1:SUS-PR2_M1_DAMP_V_GAIN = -3 H1:SUS-PR2_M1_DAMP_R_GAIN = -0.2 H1:SUS-PR2_M1_DAMP_P_GAIN = -2 H1:SUS-PR2_M1_DAMP_Y_GAIN = -1 H1:SUS-PR3_M1_DAMP_L_GAIN = -2 H1:SUS-PR3_M1_DAMP_T_GAIN = -5 H1:SUS-PR3_M1_DAMP_V_GAIN = -1 H1:SUS-PR3_M1_DAMP_R_GAIN = -0.02 H1:SUS-PR3_M1_DAMP_P_GAIN = -0.002 H1:SUS-PR3_M1_DAMP_Y_GAIN = -0.02 New PR2 and PR3 damping gains: H1:SUS-PR2_M1_DAMP_L_GAIN = -15.5 H1:SUS-PR2_M1_DAMP_T_GAIN = -2 H1:SUS-PR2_M1_DAMP_V_GAIN = -3 H1:SUS-PR2_M1_DAMP_R_GAIN = -0.2 H1:SUS-PR2_M1_DAMP_P_GAIN = -2 H1:SUS-PR2_M1_DAMP_Y_GAIN = -1 H1:SUS-PR3_M1_DAMP_L_GAIN = -20 H1:SUS-PR3_M1_DAMP_T_GAIN = -5 H1:SUS-PR3_M1_DAMP_V_GAIN = -1 H1:SUS-PR3_M1_DAMP_R_GAIN = -0.02 H1:SUS-PR3_M1_DAMP_P_GAIN = -0.02 H1:SUS-PR3_M1_DAMP_Y_GAIN = -0.2 MCWFS offsets (those should be moved to the alignment sliders): H1:IMC-MC1_PIT_OFFSET = 89.06 H1:IMC-MC2_PIT_OFFSET = 21.556 H1:IMC-MC3_PIT_OFFSET = 86.417 H1:IMC-PZT_PIT_OFFSET = 726.65 H1:IMC-MC1_YAW_OFFSET = 68.493 H1:IMC-MC2_YAW_OFFSET = 4.6945 H1:IMC-MC3_YAW_OFFSET = -69.693 H1:IMC-PZT_YAW_OFFSET = 4073.9
Forgot to mention the obvious: Hats off to the initial alignment team!
In preparation of the acceptance documentation for HSTS suspensions, PRM top mass has been tested for phase 3b after the series of MCs.
The transfer functions are showing good agreement with model and previous measurements.
The attached file is a comparison between model, phase 3a and phase 3b
files and data have been commited on the svn under the following directories :
/ligo/svncommon/SusSVN/sus/trunk/HSTS/Common/${MatlabTools/Data}
/ligo/svncommon/SusSVN/sus/trunk/HSTS/H1/PRM/SAGM1/${Data/Results}
I kept forgetting to ask this question : what do these "3a" and "3b" mean ?
See G1200070, Ideal Order/Contents of aLIGO Triple SUS Testing / Commissioning, https://dcc.ligo.org/LIGO-G1200070.
1a: Metal build assemblies, in initial assembly area (e.g., LHO staging building)
1b: Metal build fully assembled, in initial assembly area
2a: Metal build chamberside
2b: Glass build chamberside
3a: Glass build in chamber, before pumpdown
3b: Glass build in chamber, after pumpdown