[Paco, Yuta]
We checked the polarity of suspension damping loops if they follow the conventions we agreed in 40m/16898.
Suspensions are nicely homogenized nicely  , with some exceptions (see Attachment #1).
- PRM SDSEN_GAIN is 0.2, but it should be 1.
- LO1, LO2, AS1, AS SDCOIL_GAIN is +/-13, but it should be +/- 1. (Unless there are reasons for these 13)
- Let's make coil dewhitening to be off (in Acq mode) for all by default to homogenize (40m/17875). MC1 and MC3 might require 28Hz ELP for 60Hz noise.
- INMAT should be normalized nicely so that SUSPOS/SIDE_IN will be um and SUSPIT/YAW_IN will be urad. (Are cnts2um in *SEN filters correct?)
- Gain offsets in *COIL filters (e.g. V2A, x0.414) can be adjusted later to have the same actuation efficiencies between suspensions.
Note that *COIL_GAIN are now +--++ or flipped one in the order of UL/LL/UR/LR/SD.
Next:
- Address the points raised above
- Make a script to show current EPICs values for all suspensions to check the damping configurations. |
PRM/SRM OSEM input calibration
- I realized I had not yet updated the input OSEM cts2um calibration. For PRM and SRM, I changed each cts2um filter gain from 0.36 ---> 0.0417 (factor of 8.64).
- The coil output filters (V2A) had already been updated according to new actuation calibration.
PRM damping/alignment
- As noted in the previous ELOG, PRM SDSEN gain was 0.2 instead of 1. I turned on damping filters for PRM and noticed SD motion was underdamped. I changed PRM SDSEN GAIN from 0.2 ---> 1. Final PRM damping test in Attachment 1.
- With PRM alignment restored (no PIT offset in output matrix), the PRM oplev is aligned and is recording light.
- I left PRM with a misalignment offset (damping loops on; oplev loops off).
SRM damping/alignment
- I performed a damping test of SRM with the optic alignment restored (no PIT offset in output matrix). This way the OSEMs were not saturated. In this configuration, SRM passed a damping test [Attachment 2].
- However in this configuration, no light was hitting the oplev. I tried to manually align but gave up after I saw no improvement. Which raises the question, was the SRM oplev ever (recently) aligned?
- I left SRM with a misalignment offset, but in this state the OSEMs saturate and the damping loops drive unstable motion. So SRM damping loops are off.
|
To further homogenize the suspensions, we did the following changes.
- Turned on DECIMATION in PR2 URCOIL
- Changed +/- 13 in SDCOIL_GAIN of SR2,LO1,LO2,AS1,AS4 to +/-1 and increased SUSSIDE_GAIN accordingly
- PRM SDSEN_GAIN was changed from +0.2 to +1 (see 40m/17877)
- Moved FM6 "gain_offset" of gain(0.48) to FM1 in ETMY *COIL to align with other suspensions. Also added x0.48 to SDCOIL as well, and adjusted SUSSIDE_GAIN accordingly.
- "Half shorted" binary inputs to coil drivers for PR2,PR3,SR2,LO1,LO2,AS1,AS4 so that they are always in "Acq" mode. FM9 SimDW filters were turned on accordingly.
Before work today:
2023-09-28 17:10:19 UTC (GPS: 1379956237)
channel\optic MC1 MC2 MC3 BS ITMX ITMY PRM SRM ETMX ETMY PR2 PR3 SR2 LO1 LO2 AS1 AS4
ULSEN_GAIN +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00
LLSEN_GAIN +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00
URSEN_GAIN +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00
LRSEN_GAIN +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00
SDSEN_GAIN +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +0.20 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00
ULSEN_SWSTAT 37923 37923 37923 37923 37923 37923 37923 37923 37923 37923 37923 37923 37923 37923 37923 37923 37923
LLSEN_SWSTAT 37923 37923 37923 37923 37923 37923 37923 37923 37923 37923 37923 37923 37923 37923 37923 37923 37923
URSEN_SWSTAT 37923 37923 37923 37923 37923 37923 37923 37923 37923 37923 37923 37923 37923 37923 37923 37923 37923
LRSEN_SWSTAT 37923 37923 37923 37923 37923 37923 37923 37923 37923 37923 37923 37923 37923 37923 37923 37923 37923
SDSEN_SWSTAT 37923 37923 37923 37923 37923 37923 37923 37923 37923 37923 37923 37923 37923 37923 37923 37923 37923
SUSPOS_GAIN +120.00 +150.00 +100.00 +100.00 +150.00 +50.00 +28.00 +25.00 +150.00 +41.00 +8.00 +10.00 +27.00 +10.00 +10.00 +14.00 +15.00
SUSPIT_GAIN +60.00 +10.00 +24.00 +10.00 +14.00 +7.00 +5.00 +1.20 +15.00 +6.00 +2.00 +5.00 +6.00 +4.00 +3.00 +2.50 +3.10
SUSYAW_GAIN +60.00 +10.00 +8.00 +3.00 +10.00 +8.00 +4.00 +1.50 +10.00 +6.00 +2.00 +5.00 +6.00 +3.00 +3.00 +3.00 +3.00
SUSSIDE_GAIN +100.00 +150.00 +125.00 +10.00 +60.00 +50.00 +50.00 +7.50 +150.00 +300.00 +11.54 +20.00 +10.77 +3.08 +3.85 +6.54 +3.15
OL_PIT_GAIN +1.00 +1.00 +1.00 -0.05 +5.00 +3.50 +6.00 +12.68 +1.00 -1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00
OL_YAW_GAIN +1.00 +1.00 +1.00 +0.10 +5.00 -4.00 -8.00 -15.85 +1.00 -1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00
ULCOIL_GAIN +1.01 +1.07 +0.94 +1.06 -1.10 +1.06 +0.97 +1.09 -1.01 -1.00 -1.00 -1.00 -1.00 -0.94 -1.05 -0.94 -0.98
LLCOIL_GAIN -0.95 -0.98 -0.94 -0.98 +0.90 -1.01 -1.04 -1.00 +0.97 +0.81 +1.00 +1.00 +1.00 +0.98 +0.63 +0.99 +0.97
URCOIL_GAIN -0.98 -0.98 -1.04 -1.04 +0.93 -0.99 -1.04 -0.92 +1.03 +0.74 +1.00 +1.00 +1.00 +1.00 +1.34 +1.04 +0.98
LRCOIL_GAIN +1.06 +0.97 +1.08 +0.92 -1.07 +0.94 +0.90 +0.99 -0.99 -1.05 -1.00 -1.00 -1.00 -1.07 -0.98 -1.03 -1.07
SDCOIL_GAIN +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 -1.00 -1.00 -1.00 -1.00 -13.00 -13.00 -13.00 +13.00 -13.00
ULCOIL_SWSTAT 37889 38657 37889 38657 38657 38657 38657 38657 55041 38688 38400 38400 38400 38400 38400 38400 38400
LLCOIL_SWSTAT 37889 38657 37889 38657 38657 38657 38657 38657 38657 38688 38400 38400 38400 38400 38400 38400 38400
URCOIL_SWSTAT 37889 38657 37889 38657 38657 38657 38657 38657 38657 38688 5632 38400 38400 38400 38400 38400 38400
LRCOIL_SWSTAT 37889 38657 37889 38657 38657 38657 38657 38657 38657 38688 38400 38400 38400 38400 38400 38400 38400
SDCOIL_SWSTAT 37889 38657 37889 38145 38145 38145 38145 38145 38657 38656 38144 38144 38144 38144 38144 38144 38144
After work today:
2023-09-28 18:26:55 UTC (GPS: 1379960833)
channel\optic MC1 MC2 MC3 BS ITMX ITMY PRM SRM ETMX ETMY PR2 PR3 SR2 LO1 LO2 AS1 AS4
ULSEN_GAIN +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00
LLSEN_GAIN +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00
URSEN_GAIN +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00
LRSEN_GAIN +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00
SDSEN_GAIN +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00
**SEN_SWSTAT 37923 37923 37923 37923 37923 37923 37923 37923 37923 37923 37923 37923 37923 37923 37923 37923 37923
(...snip...)
SUSSIDE_GAIN +100.00 +150.00 +125.00 +10.00 +60.00 +50.00 +50.00 +7.50 +150.00 +625.00 +11.54 +20.00 +140.00 +40.00 +50.00 +85.00 +40.00
(...snip...)
SDCOIL_GAIN +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 +1.00 -1.00 -1.00 -1.00 -1.00 -1.00 -1.00 -1.00 +1.00 -1.00
ULCOIL_SWSTAT 37889 38657 37889 38657 38657 38657 38657 38657 55041 38657 38656 38656 38656 38656 38656 38656 38656
LLCOIL_SWSTAT 37889 38657 37889 38657 38657 38657 38657 38657 38657 38657 38656 38656 38656 38656 38656 38656 38656
URCOIL_SWSTAT 37889 38657 37889 38657 38657 38657 38657 38657 38657 38657 38656 38656 38656 38656 38656 38656 38656
LRCOIL_SWSTAT 37889 38657 37889 38657 38657 38657 38657 38657 38657 38657 38656 38656 38656 38656 38656 38656 38656
SDCOIL_SWSTAT 37889 38657 37889 38145 38145 38145 38145 38145 38657 38657 38144 38144 38144 38144 38144 38144 38144
ULCOIL_STAT of ETMY being 55041 is OK. 38657+2**14 = 55041.
Script to produce these tables live in /opt/rtcds/caltech/c1/Git/40m/scripts/SUS/suspension_epics_check.py
Current coil dewhitening filter situations:
| Optics |
Binary Inputs |
Run/Acq LEDs |
Enable/Disable LEDs |
Binary Outputs |
| MC1, MC3 |
lower half shorted |
off (Acquire mode; no dewhitening; FM9 28HzELP is off for now) |
all ON (Enable) |
not connected |
| MC2 |
lower half shorted |
off (Acquire mode; no dewhitening; so SimDW should be always ON) |
all ON |
not connected |
| SRM. PRM, ITMX, ITMY, BS |
lower half shorted |
off (Acquire mode; no dewhitening; so SimDW should be always ON) |
all ON |
not connected |
| ETMX |
lower half shorted |
off (Acquire mode; no dewhitening; so SimDW should be always ON) |
all ON |
not connected |
| LO1, LO2, AS1, AS4 |
lower half shorted |
off (Acquire mode; no dewhitening; so SimDW should be always ON) |
all ON |
DB9 cable |
| SR2 |
lower half shorted |
off (Acquire mode; no dewhitening; so SimDW should be always ON) |
all ON |
DB9 cable |
| PR2, PR3 |
lower half shorted |
off (Acquire mode; no dewhitening; so SimDW should be always ON) |
all ON |
DB9 cable |
| ETMY |
DB9 cable (BIO now works) |
off when SimDW is ON, ON when SimDV is off |
all ON |
DB9 cable |
Next:
- Investigate 60 Hz noise in laser frequency and check 28 Hz ELP situation for MC1,MC2,MC3
- Fix ETMX acromag |
While aligning today I realized the cavAlign step sizes and step factors had not been updated after the upgrade.
Here are the new MEDM command arguments to launch cavAlign. Only factors not equal to 1 are listed. The updates made by me are in red
| Optic pair |
Step size |
Step factor |
| PR3-ETMY |
1 |
|
| ITMY-ETMY |
1 |
|
| BS-ETMX |
1 |
|
| ITMX-ETMX |
1 |
|
| TT1-TT2 |
0.001 |
|
| PR2-PR3 |
1 |
|
| TT2-PR3 |
0.001 |
1000 |
| BS-ITMX |
1 |
|
| PR3-ITMY |
1 |
|
| SR2-AS1 |
1 |
|
| SR2-AS4 |
1 |
3.6 |
| LO1-AS4 |
1 |
|
| PRM-PR2 |
1 |
|
| ITMX-ITMY |
0.1 |
|
| TT2-PRM |
0.001 |
1000 |
Interesting notes:
- the factor of 3.6 for AS4 relative to SR2 is interesting - don't know where this comes from.
- LO1-AS4 step size was never updated from 0.001 to 1. I made the change.
- ITMX-ITMY step size for MICH was originally 0.0001. I've set the new step size to 0.1 to reflect this. |
[Rana, Radhika, Murtaza]
WFS Loop Debugging
- We turned on the WFS loops with very small gain (0.01) to see how the error signals behave. There is an existing template to look at the error signals in ndscope (users->Templates->ndscope->IOO->WFS->WFS-overview.yml). We observed C1:IOO-WFS2_IY_DQ stay at a constant offset as we increased the gain to 1.
- The output matrix for WFS (C1IOO_WFS_INMATRIX) was restored to the original value using burtgooey to mitigate the WFSoutMatBalancing.py change 17874.
- (TODO) WFS1 and WFS2 are slightly misaligned as seen on the C1IOO_LOCKMC screen. These need to be aligned when the IFO is unlocked so that the beam is centered on them.
- (TODO) With the PSL shutter turned off, WFS heads should show 0 reading which is not the case. This needs to be corrected for to mitigate the offset readings.
- The electronics upgrade should ideally only affect the suspensions (everything upstream should not need any changes).
- Note: The MC_TRANS error signals look very small in PIT and YAW. |