28 Feb 2010

  • reduced the ff matrix acquisition taken yesterday
  • ff matrix analisys that revealed actuator #220 with large fitting error

  • the previous one has been copied into the data directory (/home/aoacct/src/conf/adsec/672a/data) with the full name: 2010_02_28_ff_matrix_+5.999e-05_3.400e-06m_LBT_001.sav
    • new acquisition of FF matrix with 10 iterations
    • reduction of FF acquired data has confirmed the large residual on act #220

  • EMERGENCYSTOP at 20:47:53.047680 in the log file: FASTDGN00:
    FASTDGN00 |WAR| 247048|2010-02-28 20:47:53.047680| FUNCTEMERGENCYST > CHDISTAVERAGE-0000 = 0.00791027 [/home/aoacct/src/DiagnApp/Funct.h:258]
    FASTDGN00 |INF| 247049|2010-02-28 20:47:53.047699| ADAM > Adam: disabling coils...
    FASTDGN00 |DEB| 247050|2010-02-28 20:47:53.047722| ADAM > Command to Adam: #011300
    FASTDGN00 |DEB| 247051|2010-02-28 20:47:53.048353| ADAM > Answer from Adam: >01^M#011300
    FASTDGN00 |ERR| 247052|2010-02-28 20:47:53.048371| ADAM > Adam: coils disabling failed
    FASTDGN00 |ERR| 247053|2010-02-28 20:47:53.048395| FUNCTEMERGENCYST > ADAM CAN'T DISABLE COILS [/home/aoacct/src/DiagnApp/Funct.h:263]
    FASTDGN00 |ALW| 247054|2010-02-28 20:47:53.048413| FUNCTEMERGENCYST > dumpadsecdiagnhistory succesfully sent to masterdiagnostic [/home/aoacct/src/DiagnApp/Funct.h:280]
    Act#0 was found to have an AveDist 7.9mm, it seems to be a problem of the accumulator. Some process (xadsec?) caused the accumulator to not end the accumulation.
    The Adam error is not related to this problem, is a known bug to be fixed.

  • Set and flat the shell:
    • command: fsm_set_flat()
    • number of modes applied for flattening: 391
    • Peak force: 0.23N
    • the AO gains have been successfully applied

  • Test noise with AO gains:
    • the test showed an oscillation astigmatism-like 90nm rms on the peak actuator
    • Immagine1.png

  • Temporal history with AO gains
    • FFT on act#244 shows the oscillation at about 620Hz
    • possibly mountain conditions (air density? It shouldn't) change the dynamical behavior
    • it is not related with shell-mounting beams or crate geometry. It shouldn't be an electronic problem related to faulty component.
    • Immagine2.png

  • Set and flat the shell with low proportional gain (0.02N/um) and no derivative:
    • command: fsm_set_flat(/FF)
    • number of modes applied for flattening: 379
    • Peak force: 0.21N
    • this low-gain configuration to check that previous oscillation with lower gains

  • Test noise with low gains (0.02N/um, no deriv):
    • two test acquired on the row
    • the shell reset during the test, for sure was reset during the second, probably reset during the first (outermost acts 300nm rms noise!)

  • Set and flat the shell again with low proportional gain (0.02N/um) and no derivative:
    • command: fsm_set_flat(/FF)
    • number of modes applied for flattening: 396
    • Peak force: 0.20N
    • this low-gain configuration to check that previous oscillation with lower gains

  • Test noise with low gains (0.02N/um, no deriv):
    • noise < 4.4nm rms, no astigmatic structure (as espected)
    • the usual crate structure is present
    • Immagine3.png

  • Set and flat the shell:
    • command: fsm_set_flat()
    • number of modes applied for flattening: 396
    • Peak force: 0.22N
    • the AO gains have been successfully applied

  • Test noise with AO gains:
    • similar behaviour: the test showed an oscillation astigmatism-like 72nm rms on the peak actuator
    • Immagine4.png

  • removed interface to coldplate of the mounting-beams
    • test noise showed a reduction of the oscillation amplitude more than 50%:
    • Immagine5.png
  • reducing proportional gain from 0.13N/um to 0.10N/um the oscillation disappears:
    • Immagine6.png
    • Immagine7.png
  • With proportional gain 0.11N/um the autoscillation restarts:
    • Immagine8.png
    • Immagine9.png
  • next steps:
    • installing the miniskirt and than remove the mounting-poles (to work in the final condition, removing part of the mounting support the oscilation educed a factor 2)
-- RunaBriguglio - 28 Feb 2010
I Attachment Action Size Date Who Comment
Immagine1.pngpng Immagine1.png manage 83 K 01 Mar 2010 - 05:39 ArmandoRiccardi  
Immagine2.pngpng Immagine2.png manage 55 K 01 Mar 2010 - 05:40 ArmandoRiccardi  
Immagine3.pngpng Immagine3.png manage 215 K 01 Mar 2010 - 05:42 ArmandoRiccardi  
Immagine4.pngpng Immagine4.png manage 203 K 01 Mar 2010 - 05:44 ArmandoRiccardi  
Immagine5.pngpng Immagine5.png manage 203 K 01 Mar 2010 - 05:48 ArmandoRiccardi  
Immagine6.pngpng Immagine6.png manage 215 K 01 Mar 2010 - 05:53 ArmandoRiccardi  
Immagine7.pngpng Immagine7.png manage 72 K 01 Mar 2010 - 05:55 ArmandoRiccardi  
Immagine8.pngpng Immagine8.png manage 209 K 01 Mar 2010 - 05:57 ArmandoRiccardi  
Immagine9.pngpng Immagine9.png manage 64 K 01 Mar 2010 - 05:58 ArmandoRiccardi  
Topic revision: r5 - 01 Mar 2010, ArmandoRiccardi
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