Laser ranging distomats

oct 2002


Replacements for distomats:

demetrix Laser sensor (FLS-10):
Testing TRelectronics distomat (apr-jun11)
apr11: testing accurange 3000 distomat replacement.


1991:How much vertical motion do we have with the DI1001 distomats at 157 meters.
azimuth to use when vertically aligning the distomats
monitoring the distomat dropouts  and the modification log


wild di1001 specs: ( I think this was one of the orignal distomats).

11apr14: distomat failures by hour of day.

    Distomat 3 has not been working very well for the last month or 2. This  has caused the laser ranging measurement to fail (it needs all 6 distomats to measure the platform position). 

    The tiedown tracking uses the distomat measurements to keep the platform at the correct height. If their is no measurement, then the platform remains in the current position.

    I plotted  distomat failures by hour of day for 12mar14 to 11apr14 (10am). For each hour of each day i marked the hour ok  if there was at least 1 valid distomat measurement during this hour.

    The plot shows the distomat measurements by hour for 12mar14 to 11apr14 (.ps)  (.pdf)


processing: x101/140411/

08jun12: test distomat mounted on dist6. dist6 goes out of alignment

    On 07jun12 a test distomat was mounted on the side of distomat 6 canister. This caused distomat 6 to go out of alignment. Galfacts (as2130) ran from 20:00 to about 2:30 the next morning. Their setup was:

distomat 6 measurements failed whenever the za got less than 6 deg. Corner 12 was at a low point when this occurred, so distomat 6 is pointing too high.
When this occurred,the platform height was close tot he correct position (1256.22 feet)

The plots show the az,za and distomat measurement times (.ps) (.pdf)
Distomat 6 needs to be realigned.

processing: 120608/

Azimuth angles to use when aligning the distomats.  (top)

    The easiest way to align the distomats is to position the azimuth arm perpendicular to the corner where the distomat is pointing. This should leave that corner at the average platform height. It does not matter where the dome/ch is.
Azimuth angles:
  1. distomats 1,6  (corner T12) move the azimuth to 92.87, 272.87, or 452.87 degrees (whichever is closer)
  2. distomats 2,3 (corner T4) move the azimuth to 32.87, 212.87, or 392.87 degrees (whichever is closer).
  3. distomats 4,5 (corner T8) move the azimuth to  152.87, 332.87 or 512.87 degrees (whichever is closer).
Try and center the distomats vertical range on this position.

Some things to keep in mind.


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