Computing the cable xz vertical angle

19oct20
plots:
Over plot platform xz cable angles for 3 computation methods (.ps) (.pdf)
Over plot backstay  xz cable angles for 3 computation methods (.ps) (.pdf)

Other pages:
Cable tensions from the p50 sag survey
Tower4 auxNorth failure


Intro (top)

    Let x,y be in the horizontal plane,and z  is positive up. The sag survey computation rotates the cable datapoints into the xz plane and the fits a catenary.   
To compute the cable tension from the sag survey, you need to know the vertical (xz) angle of the cable.
Assume the catenary fit is:

   Prior to fitting for the catenary i did a 2nd order fit to remove outliers:

    Up until 19oct20 i was using the c1 coef from the fit to compute the xz angle.
When i distributed the results  of the cable tensions , pierre ghisbain pointed out that the vertical angles i reported were not consistent

Computing the vertical angles from the fits.

    When fitting a catenary to each cable data set:

Plots were made showing the (measured xzangle - drawingsXzangle) for the platform and backstay cables.

Over plot platform xz cable angles for 3 computation methods (.ps) (.pdf)

Over plot backstay  xz cable angles for 3 computation methods (.ps) (.pdf)



Summary:

  processing: x101/p50/cables/xzangle/chkxzangle.pro, chkxzangleplot_plat/bstay.pro


 home_~phil