DX 4D flattening of TS3 - 20180206

DLMiller and a dozen more......

Times in UT

Mike, Andrew, Pat have redirected the TMS diameter measurement on DX so that it measures the M1-RetroReflector distance in quasi-realtime by having a retroreflector mounted on the RetroReflector. This was mostly used for watching the vibration in real time rather than saving large quantities of data.

17:35 Noise data: Normal Setup
  • 4D aligned and flattened
    • flat 175539
  • 20180206_175300_noise 47 us - chiller OFF
  • 20180206_175600_noise 31 us - chiller OFF
  • 20180206_175800_noise 31 us - chiller OFF

OVMS Telemetry is being saved in parallel to the collection of 4D data.

18:11 Noise data: LUCI2 air off
  • 20180206_181200_noise 31 us - chiller ON
  • 20180206_181300_noise 31 us - chiller ON
  • 20180206_181500_noise 300 samples - chiller ON

18:25 Noise data: LUCI1 and 2 air off, Primaries lowered.
  • 20180206_182500_noise - chiller ?/tmp/ovms.mode2.20180206lbcobs.jpg
  • 20180206_182600_noise - chiller ?
  • 20180206_182700_noise 300 samples - chiller OFF

18:32 Noise data: LUCI1 and 2 air off, Primaries lowered. SX and DX M2 Hex off
  • 20180206_183300_noise - chiller OFF
  • 20180206_183400_noise - chiller OFF
  • 20180206_193300_noise (INCORRECT TIME?)
  • produce 20180206_193300_noise

18:38 Auto raise both primaries

18:43-18:54 Pat is turning off all 4 treehouse ventilation fans (setting their speeds to 0 Hz)

18:51 DX Hexapod
  • hex global 2.287, -0.234, 2.84, 58, 494.55l
  • hex total 2.287, -0.124, 2.84, 57.2, 494.4/tmp/ovms.mode2.20180206lbcobs.jpg

19:07 flatten with 50 modes
  • 191224

19:08 All 4 treehouse vent fans off
  • 20180206_190800_noise - chiller OFF
  • 20180206_191000_noise - chiller OFF
  • 20180206_191100_noise 300 - chiller OFF

19:15 Both M3s servos off (de-init button), All 4 treehouse vent fans off
  • 20180206_191600_noise - chiller OFF
  • 20180206_191800_noise - chiller OFF
  • 20180206_191900_noise - chiller OFF
  • 20180206_192000_noise 300 - chiller OFF
    • produce 20180206_192000_noise

19:30 LN off, Both M3s servos off (de-init button), All 4 treehouse vent fans off
  • 20180206_193300_noise - chiller ON
    • produce 20180206_193300_noise
  • 20180206_193400_noise - chiller ON

19:35 LBTI Cold Heads off, LN off, Both M3s servos off (de-init button), All 4 treehouse vent fans off
  • 20180206_193600_noise - chiller ? (reduced power unloaded state)
  • 20180206_193800_noise - chiller ?
  • 20180206_193900_noise 300 - chiller ?
    • produce 20180206_193900_noise 300

19:xx Summer Chiller off, LBTI Cold Heads off, LN off, Both M3s servos off (de-init button), All 4 treehouse vent fans off
  • 20180206_194100_noise - chiller ?
  • 20180206_194200_noise 300 - chiller OFF

19:48 Summer Chiller off, LBTI Cold Heads + electronics off, LN off, Both M3s servos off (de-init button), All 4 treehouse vent fans off
  • 20180206_194800_noise - chiller OFF
  • 20180206_194900_noise - chiller OFF
  • 20180206_195000_noise 300 - chiller OFF
    • produce 20180206_195000_noise 300

20:06 6 AGw's off, Summer Chiller On, LBTI Cold Heads on, LN off, Both M3s servos off (de-init button), All 4 treehouse vent fans off
  • 20180206_200600_noise - chiller ON
  • 20180206_200800_noise - chiller ON
  • 20180206_201000_noise 300 - chiller ON

20:20 ICS disabled
  • 20180206_201900_noise - chiller ?
  • 20180206_202300_noise - chiller OFF

20:32 ICS enabled (on)

20:47 Az/El/Bldg on, stow pins out
  • 20180206_204700_noise - chiller ON
  • 20180206_204900_noise - chiller ON
  • 20180206_205000_noise 300 - chiller ON
  • 20180206_205500_noise - chiller ? (787 frames)

21:08 Az/El/Bldg drives off, stow pins inserted

21:22 LRTH fan on (7.5 Hz - maybe)

21:26 LLTH fan on (9.0 Hz - likely)

21:30 ULTH fan on (14.3 Hz - definite)

21:36 URTH fan on (18.8 Hz - definite)

Analysis

Plot 21.31-0.04 All treehouse off

Plot 21.405-0.04 : LRTH fan on (7.5 Hz - maybe)

Plot 21.485-0.04 : LRTH+LLTH fan on (9.0 Hz - likely)

Plot 21.575-0.04 : LRTH+LLTH+ULTH fan on (14.3 Hz - definite)

Plot 21.780-0.04 : All Treehouse+LN on URTH fan on (18.8 Hz - definite)

21:41 L-N powered back on

21:50 Summer Chiller off, Both M3s servos off (de-init button), on Oil but drives off
  • 20180206_215000_noise - chiller OFF (787 frames)
  • 20180206_215200_noise - chiller OFF (787 frames)
  • 20180206_215300_noise 300 - chiller OFF

22:06 Turning off HBS
  • 20180206_220600_noise - chiller ON (787 frames)
  • 20180206_220700_noise - chiller ON (787 frames)
  • 20180206_220800_noise 300 - chiller ON

22:21 Setting sample to 1/2
  • 20180206_222100_noise 300 - chiller OFF
    • produce 20180206_222100_noise
  • 20180206_223900_noise 300 - chiller ON

Summary

Preliminary Lack of Conclusions from Vibration Testing with 4D, OVMS and TMS on 20180206

a) The new thing for today is that Mike, Andrew, Pat have redirected the TMS primary diameter measurement on DX so that it measures the M1-RetroReflector distance in quasi-realtime by having a retroreflector mounted on the RetroReflector. This was mostly used for watching the vibration in real time rather than saving large quantities of data. What we see is a fairly clean looking sine wave at approx 14 Hz (not a precise frequency measurement) with an amplitude of 1 micron p-v with occasional bumps up to 15 microns. This is measuring mostly piston, as the distance is from the edge of M1 up to the retroreflector. This geometry is only somewhat sensitive to the tip-tilt vibrations that are bothering the 4D. Maybe the amplitude decreased when we turned off the treehouse ventilation, but we never got a eureka moment when the vibration disappeared.

b) We took loads of 4D interferometry data while turning many things on and off. Special thanks to Pat for running all over the telescope to turn things on/off. These included LUCI window air supply, lower both primary mirrors, set brakes and turn off M2 hexapod servos, all 4 treehouse ventilation fans, de-init both M3 tip-tilts, power off L-N, power off LBTI, disable ICS, AZ,EL,Bldg servos on with stow pins out, HBS oil off. After ALL of that we still have not found a source of the tip-tilt vibrations that are bothering 4D, although we do see factors of 3-ish variations in the noise from one data set to the next. The remaining hope is that (based on 3 datasets out of 26) we may see a correlation between 4D noise and whether the summer chiller was running. Doug is processing all the other datasets this evening, so we can learn later whether the chiller is actually contributing vibration.

c) The success of the day was that while all the above turning off and turning on was happening, Phil was watching the OVMS signal for the 2 working accelerometers mounted on LBTI. At ~19:30 UT, when we had lots of things turned off, he noticed that the 120 Hz signal associated with Issue 7005 was significantly reduced compared to its amplitude over the last couple weeks. When things were turned back on near 21:41 UT, it seemed to be L-N that caused this 120 Hz vibration to come back. Probably we need another confirmation measurement to prove that L-N is the culprit.

d) By turning the treehouse ventilation fans back on one by one, we have the OVMS data to say which lines in the PSD belong to which fan. Times are reported in 20180206_DX_Day in the Adaptive Optics wiki. (I haven't extracted the data yet.)

e) The mysterious 81 Hz line in the OVMS+ TT PSD that first appeared strongly on Saturday evening through Monday afternoon was in the "low state" all day. It returned to the high state during observing in the evening.

Data Analysis Notes

tn1=['20180206_190800_noise', '20180206_191000_noise', '20180206_191100_noise','20180206_191600_noise','20180206_191800_noise','20180206_191900_noise']

tn2=['20180206_193400_noise','20180206_193600_noise','20180206_193800_noise','20180206_194100_noise','20180206_194200_noise','20180206_194800_noise','20180206_194900_noise']

tn2a=['20180206_194200_noise','20180206_194300_noise','20180206_194800_noise','20180206_194900_noise']

tn3=['20180206_200600_noise','20180206_200800_noise','20180206_201000_noise','20180206_201900_noise','20180206_202300_noise','20180206_204700_noise','20180206_204900_noise']

tn4=['20180206_205000_noise','20180206_205500_noise','20180206_215000_noise','20180206_215200_noise','20180206_215300_noise','20180206_220600_noise','20180206_220700_noise','20180206_220800_noise']

tn4a=['20180206_215200_noise','20180206_215300_noise','20180206_220600_noise','20180206_220700_noise']

For asma_opt_noise_new

tn6=['20180206_205000_noise','20180206_205500_noise','20180206_215000_noise','20180206_215200_noise','20180206_215300_noise']
tn7=['20180206_220600_noise','20180206_220700_noise','20180206_220800_noise','20180206_224100_noise']

list1=['20130826_102500_noise','20130826_140000_noise','20130827_041100_noise','20130827_050556_noise','20130827_060000_noise']
list2=['20130827_100300_noise','20130830_142700_noise','20130831_085800_noise','20130831_111500_noise','20130831_131400_noise']

list3=['20170901_064300_noise','20170901_082400_noise','20170901_092500_noise','20170901_093700_noise','20170907_205243_noise_idl','20170907_210334_noise_idl','20170907_211015_noise_idl','20170907_212048_noise_idl']

list4=['20170907_212958_noise_idl','20170907_220700_noise_4d','20170907_221600_noise_4d','20170907_221732_noise_idl','20170907_222027_noise_idl','20170912_181300_noise_4d','20170912_223800_noise_final','20170912_224000_noise_final']


-- %USERSIG{DougMiller - 2018-02-06}%

  • OVMS TT for Many Things Off:
    ovms.mode2.20180206ManyThingsOff.jpg

  • OVMS TT for Primaries Off and Hexapods Off:
    ovms.mode2.20180206PrimariesOffHexapodsOff.jpg
I Attachment Action Size Date Who Comment
ovms.mode2.20180206ManyThingsOff.jpgjpg ovms.mode2.20180206ManyThingsOff.jpg manage 2 MB 09 Feb 2018 - 20:53 JohnHill OVMS TT for Many Things Off
ovms.mode2.20180206PrimariesOffHexapodsOff.jpgjpg ovms.mode2.20180206PrimariesOffHexapodsOff.jpg manage 2 MB 09 Feb 2018 - 20:59 JohnHill OVMS TT for Primaries Off and Hexapods Off
ovms.mode2.20180206TreeHouseFansOff.jpgjpg ovms.mode2.20180206TreeHouseFansOff.jpg manage 1 MB 09 Feb 2018 - 20:57 JohnHill OVMS TT for TreeHouse Fans Off
Topic revision: r13 - 16 Feb 2018, JohnHill
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