Theodolite survey of dome from ao9 monument before and after shimming
Feb. 2003
links to plots:
04feb03:
compare 04feb03 survey (before shimming) with aug01 survey.
04feb03:
ao9 survey results.
12feb03:
ao9 survey results.
17feb03:
ao9 survey results.
17feb03:
ao9 survey 1,3az,za fits to theodolite data
17feb03:
comparing the 3 surveys 17,12,04feb03
17feb03:
calibrating the tilt sensors to 17feb03 ao9 survey.
18feb03:
creating a pitch,roll model from the 18feb03 tilt sensor swings.
19feb03:
creating a pitch,roll model from the 19feb03 tilt sensor swings.
20feb03:
creating a pitch,roll model from the 20feb03 tilt sensor swings.
25feb03:
creating a pitch,roll model from the 25feb03 tilt sensor swings.
28feb03:
creating a pitch,roll model from the 28feb03 tilt sensor swings.
links to sections:
Intro
04feb03: ao9 survey before shimming.
12feb03: ao9 survey after first shimming.
17feb03: ao9 survey after 'most' shimming.
Comparing survey aug01
with 04feb03 survey before shimming.
Comparing the feb03 ao9
surveys: 17feb03,12feb03,04feb03.
Calibrating
the tilt sensors using the 17feb03 ao9 data.
Using the 18feb03 tilt
sensor swings to generate a pitch,roll model
Using the 19feb03 tilt
sensor swings to generate a pitch,roll model
Using the 20feb03 tilt
sensor swings to generate a pitch,roll model
Using the 25feb03 tilt
sensor swings to generate a pitch,roll model
Using the 28feb03 tilt
sensor swings to generate a pitch,roll model (after dome move)
Intro.
The elevation rails were shimmed
and the dome raised in feb03. The relevant dates are:
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04feb03: Theodolite ao9 survey before shimming starts.
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05-08feb03: first round of shimming.
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12feb03: 2nd survey from ao9 to check shimming.
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13-17feb03: shimming continues and "supposedly finishes" on 17feb03.
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17feb03: Theodolote ao9 survey.
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18-25feb03: Shimming continues.
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18,19,20,25feb03: tilt sensor runs to see how the shimming is progressing.
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27feb03: dome lifted 1.65 inches.
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28feb03: weight added to the platform (6200 lbs) to compensate for
T8 hairpin correction
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28feb03: tilt sensor run to measure the pitch, roll errors after
all changes.
The changes to the platform took longer than expected.
There was no final ao9 survey with the theodolite to measure the pitch,roll,
focus errors after all of the changes (the survey was finally done in jul03).
The models made were relative to the 17feb03 theodolite survey. There were
large changes after this..
04feb03 ao9 survey before
shimming. (top)
A survey was done from ao9 on 4feb03 before any shimming
was done. 2 zastrips at azimuths of 242.87 and 302.87 degrees were.
The the
plots show the results of the survey for the two za strips.
-
Fig 1 top. This is the computed pitch (black), roll (red), and focus (green)
error from the theodolite measurements. The pitch and roll units are in
degrees. The focus is in inches/10 (the min focus value is about -2 inches).
The separation in the strips come from the 3 azimuth terms of the pitch
and the roll.
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Fig 1 Bottom. This is the laser ranging data showing the motion of the
platform in inches during the survey. The peak to peak motion is about
.3 inches vertically.
-
Fig 2. The surveyed data defines an azimuth and za position. These plots
are the difference between the theodolite computed position and that of
the encoders. The differences should match the pointing model error.
Processing:survey/030204/reduc/pltsurvey.pro
ao9 survey 12 feb03 after
first shimming. (top)
The first round of shimming was completed and then a
survey from ao9 was done on 12feb03. 2 zastrips at azimuths of 242.87 and
302.87 degrees were done followed by an azimuth swing at za of 10 degrees.
The the
plots show the results of the survey for the two za strips.
-
Fig 1 top. This is the computed pitch (black), roll (red), and focus (green)
error from the theodolite measurements. The pitch and roll units are in
degrees. The focus is in inches/10 (the min focus value is about -2 inches).
The separation in the strips come from the 3 azimuth terms of the pitch
and the roll.
-
Fig 1 Bottom. This is the laser ranging data showing the motion of the
platform in inches during the survey. The peak to peak motion is about
.3 inches vertically.
-
Fig 2. The surveyed data defines an azimuth and za position. These plots
are the difference between the theodolite computed position and that of
the encoders. The differences should match the pointing model error.
-
Fig 3-5 show the pitch,roll, and focus error versus azimuth and za. The
length of the vector is proportional to the error. The angle relative to
up is also proportional to the error (90 deg to the right is .75 of max,
while down is .5 of max).
processing:survey/030212/reduc/pltsurvey.pro
ao9 survey 17 feb03 after
'most' shimming. (top)
Shimming was completed (or so we thought) on 17feb03.
A survey from ao9 was done that evening. 2 zastrips at azimuths of 242.87
and 302.87 degrees were done followed by an azimuth swing at za of 10 degrees.
The the
plots show the results of the survey for the two za strips and the az swing.
-
Fig 1 top. This is the computed pitch (black), roll (red), and focus (green)
error from the theodolite measurements. The pitch and roll units are in
degrees. The focus is in inches/10 (the min focus value is about -2 inches).
The separation in the strips come from the 3 azimuth terms of the pitch
and the roll.
-
Fig 1 center is the same data plotted versus azimuth.
-
Fig 1 Bottom. This is the laser ranging data showing the motion of the
platform in inches during the survey. The peak to peak motion is about
.3 inches vertically.
-
Fig 2. The surveyed data defines an azimuth and za position. These plots
are the difference between the theodolite computed position and that of
the encoders. The differences should match the pointing model error.
processing:survey/030217/reduc/pltsurvey.pro
The second
plot shows az,za fits to the theodolite data.
processing:survey/030217/reduc/pltfit.pro
Comparing
survey aug01 with feb03 survey before shimming. (top)
The plots
show the difference in the pitch, roll , and focus between the aug01
survey and the feb03 survey before the shimming.
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Fig 1. This has is the pitch, roll, and focus errors. The black was measure
on 04feb03 before shimming. The red was measured on 09aug01 and was used
for the shim computations. This used the reflector as the origin. The green
plot is a modification of the 09aug01 data using a slightly different radius
(lynn baker's update of july02).
Fig 2 shows the difference between the measurements of 09aug01 that
were used for the shim computations and the data taken on 04feb03 (black).
The red plot is the difference between 09aug01 data and the update of jul02.
Comparing
the feb03 ao9 surveys 17feb03,12feb03,04feb03. (top)
The plots
shows the results of the ao9 surveys for 17feb03, 12feb03, and 4feb03 .
The rails were shimmed above 10 deg za and on the carriage house side.
The pitch and roll data for za 6 to 10 degrees have not changed for the
3 surveys. The pitch and roll data below six degrees changed for the 3
surveys. The ch side was shimmed so this should affect out to maybe 3 degrees
za (38feet is extent of gr trolleys). What is not believable is the
roll change below 6 degrees za 04feb to 12feb and then the return to the
04feb values on 17feb03. I don't believe any shimming is that accurate
(even if they tried it). The difference must been in the computations of
the pitch, roll. It is not a movement of the platform since the two za
strips 242 and 302 were separated by 2 hours yet they do the same thing.
processing:survey/030217/reduc/comparesurvey.pro
Calibrating
the tilt sensors using the 17feb03 ao9 data. (top)
The tilt sensor data taken during the 17feb03 AO9 survey
was used to calibrate the tilt sensors.
The plot
shows the theodolite data and the fits.
processing:survey/030217/reduc/cmptsoffset.pro
A description of the method can be found under tilt
sensor calibration using the theodolite.
Using
the 18feb03 tilt sensor swings to generate a pitch,roll model (top)
The tilt sensor data taken on 18feb03 was corrected
to the theodolite reference and then a 2d model was fit to this data.
The plot
shows how well the model works.
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Fig 1. Shows the pitch of the tilt sensors, the tilt sensor model,
and the theodolite measured points.
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Fig 2. has the roll of the tilt sensors, the tilt sensor model, and the
theodolite measured points.
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Fig 3. plots the residuals of the model - the tilt sensor data.
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Fig 4 has the residuals of the Theodolite - model for the theodolite points.
The 2d fit worked pretty well for pitch and roll. It fit the tilt sensor
data and was able to recreate the theodolite data. The next day (19feb03)
had trouble fitting the roll.
processing:survey/030217/reduc/do2dfit_18feb03.pro
A description of the method can be found under tilt
sensor calibration using the theodolite.
Using
the 19feb03 tilt sensor swings to generate a pitch,roll model (top)
The tilt sensor data taken on 19feb03 was corrected
to the theodolite reference and then a 2d model was fit to this data.
The plot
shows how well the model works.
-
Fig 1. Shows the pitch of the tilt sensors, the tilt sensor model,
and the theodolite measured points.
-
Fig 2. has the roll of the tilt sensors, the tilt sensor model, and the
theodolite measured points.
-
Fig 3. plots the residuals of the model - the tilt sensor data.
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Fig 4 has the residuals of the Theodolite - model for the theodolite points.
The pitch is fitting pretty well. The roll does not fit very good. The
2dmodel fits the tiltsensor data, but the tilt sensor data does not agree
with the theodolite data. There are two separate tracks over each
za strip which differ by about 3 hours. They track each other very
well. The shape difference is hard to reconcile with the calibration of
tilt sensor to theodolite (they only use linear terms in za).
processing:survey/030217/reduc/do2dfit_19feb03.pro
A description of the method can be found under tilt
sensor calibration using the theodolite
Using
the 20feb03 tilt sensor swings to generate a pitch,roll model (top)
The tilt sensor data taken on 20feb03 was corrected
to the theodolite reference and then a 2d model was fit to this data.
The plot
shows how well the model works.
-
Fig 1. Shows the pitch of the tilt sensors, the tilt sensor model,
and the theodolite measured points.
-
Fig 2. has the roll of the tilt sensors, the tilt sensor model, and the
theodolite measured points.
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Fig 3. plots the residuals of the model - the tilt sensor data.
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Fig 4 has the residuals of the Theodolite - model for the theodolite points.
The pitch is fitting pretty well. The roll does not fit very good. The
2dmodel fits the tiltsensor data, but the tilt sensor data does not agree
with the theodolite data. This looks the same as the 19feb03 data.
processing:survey/030217/reduc/do2dfit_20feb03.pro
A description of the method can be found under tilt
sensor calibration using the theodolite
Using
the 25feb03 tilt sensor swings to generate a pitch,roll model (top)
The tilt sensor data taken on 25feb03 was corrected
to the theodolite reference and then a 2d model was fit to this data.
The plot
shows how well the model works.
-
Fig 1. Shows the pitch of the tilt sensors, the tilt sensor model,
and the theodolite measured points.
-
Fig 2. has the roll of the tilt sensors, the tilt sensor model, and the
theodolite measured points.
-
Fig 3. plots the residuals of the model - the tilt sensor data.
-
Fig 4 has the residuals of the Theodolite - model for the theodolite points.
The pitch is fitting pretty well. The roll does not fit very good. The
2dmodel fits the tiltsensor data, but the tilt sensor data does not agree
with the theodolite data. This looks the same as the 19feb03 data.
processing:survey/030217/reduc/do2dfit_25feb03.pro
A description of the method can be found under tilt
sensor calibration using the theodolite
Using
the 28feb03 tilt sensor swings to generate a pitch,roll model (after
dome move)(top)
The tilt sensor data taken on 28feb03 was corrected
to the theodolite reference and then a 2d model was fit to this data. This
data was taken after all of the shimming and after the dome move.
The plot
shows how well the model works.
-
Fig 1. Shows the pitch of the tilt sensors, the tilt sensor model,
and the theodolite measured points.
-
Fig 2. has the roll of the tilt sensors, the tilt sensor model, and the
theodolite measured points.
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Fig 3. plots the residuals of the model - the tilt sensor data.
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Fig 4 has the residuals of the Theodolite - model for the theodolite points.
This shows how much we moved the pitch and roll from the 17feb03 survey.
We need to do another theodolite survey to get the focus correct (after
moving the dome). At that time we should be sure and do at least 2 az swings
(along with the za strips) to nail down the az dependence.
processing:survey/030217/reduc/do2dfit_28feb03.pro
A description of the method can be found under tilt
sensor calibration using the theodolite
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