Notes for jim gould/ammann & whitney
Computing the ubalanced
loads on the azimuth arm. This includes:
- dome moves 1.06 to 19.69 deg za with:
- ch za at stow (8.83)
- ch za at 20 deg
- ch tracks dome za when dome za above za=10deg.
New operational limits for the telescope provide by ammann and whitney
- Shows the allowable dome za range vs az,za, and temperature.
allowable za range for dome,ch after beam fixed.
- This shows the unbalanced load as we move dome 6 - 10 degrees
with ch and stow
- Also shows unbalance with ch 0 to 20 and dome at 8.4
- Includes unbalance in az for temps: 65,70,80,85,90 F
az swings to find where dome balances azimuth arm.
- Ch at stow
- Fit 1az term to tiedown tensions vs az. find za for 0 tension
change during az swing.
- with ch at 8.835 degrees, the az arm is balanced with the dome
at 7.968 degrees (this the optic axis ,encoder value)
allowable telescope motion immediately after the repair.
tiedown tensions vs az,za,temp when platform in focus. This
- all of this has the carriage house at stow (8.83) and the
platform in focus (1256.22 feet).
- Total tiedown tension vs temperature (60 to 90 degF)
- Tiedown tension by corner for temps: 70F,80F,85F, and 80F. At
each temp you have:
- tension vs dome za (1.06 to 19.69deg). this is shown for
- Tension vs azimuth (0 to 360 deg). This is shown for dome
- 1998 weighing of dome with jacks
- 2002 weighing of dome using dome motor torques.
- 2003 weighing of dome with jacks and load cells.
fitting the tiedown tensions to az,zagr,zach,tiedown position,temps
using 2008,2009 data.
- Fits the tiedown tension at each corner to az, zagr,zach,temp,
and tiedown position using data from 2008,2009.
- histograms of temp, az, grza, chza, tiedown positions, and
tensions for the two years.
- The coefficients of the fit:
- tension increase per deg F
- tension increase per td inch moves.
- the dome center of mass za is 1.9 degrees downhill
from the dome optical axis za.
- Error in the fit tensions vs hour of day shows how the cable
temp differs from temp sensor.
loading of tiedowns from telescope motion. Shows measured td
tensions vs az for:
- tracking a source (platform in focus)
- Moving dome 2-19 degres in za while az at 0 degrees (platform
- Az -180 to 180 with dome at 15deg, ch at 0 degrees (platform
not in focus).D
- You can read the az,za off of the plots and then the
corresponding td tensions.
- 17feb10:TdTensions for dome=15,ch=0,
- The plots were used by jim as input so his model.
- data from 19jan10 aeronomy az swing 0-2am.
cable sag measurements
- This has the az,za and tiedown tensions during the cable sag
corner deflection when ch moves 2-20 degrees za (za dome=19.6)
- Shows how much a platform corner moves when the ch changes za.
- The dome was fixed
at 19.6 za.
- dec03:platform corner
deflection when dome moves 2-20 degrees za (za ch=8.835).
- Shows how much a platform corner moves when the dome changes
- The ch was fixed
at stow (8.834 deg) za.
- how much the platform moves when you pull on a tiedown.
- How much the platform moves with temperature (all other things