tie down Position vs platform position and temp (2002)

feb 2003

    The 2002 td,distomat data was passed through the filter:
  • tension difference pair of cables less than 4 kips
  • temperature 60 to 95F
  • height within .4 feet of 1256.35
  • kips per cable between 5 and 65 kips.
  • carriage house at stow.
  • platform height at least .01 feet from 1256.35 (most points are here).
  • Tiedown Inches motion per platform Inch of Motion.

        The data was  binned in temperature 70 to 85 deg F (1 deg F wide). Fits were made to the function: avgTdPos=c0+c1*(platformHght-1256.35)*12 at constant temp. The plots show the change in tiedown height versus change in platform height  for these temperatures:     Historically we have been using -1.77 tiedown inches per platform inch. This was measured back in the year 2000 at a single temp.


    summary:

     
    Parameter constraint fit
    tdIn/Platform Inch:-1.73 tdIn/plIn (avg 70-85F) constant temp -1.718+.012722*t-.001664*t^2 (t=temp-73F)
    tdInch/degF: -.3512  constant PlHght
    1256.35 used
    tdPosAtFocus: 11.9628-.3512*(temp-73F)
    plInch/degF: .203  (using .3512/1.73)

     
    processing: x101/td/2002/yr2002Fit.pro
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