I created a case of the Mathematica model TwoWireSimpleBlades to represent the HTTP (Tip-Tilt) in the SVN at
^/trunk/Common/MathematicaModels/TwoWireSimpleBlades/20130627TipTilt
and a matching Matlab parameter set at
^/trunk/Common/MatlabTools/SingleModelProduction/httsopt_test.m
in the SVN. There's also a wiki page with parameters, a mode frequency table and mode shape plots:
I used parameters from P1100090-v5 = Rev. Sci. Instrum. 82, 125108 so it should be close to reality, although there are a few minor issues of interpretation that will hopefully be cleared up in the next few days.
I also renamed the Matlab HAUX parameter set in the same directory from hauxtest.m to hauxopt_test.m to parallel other such files, and edited generate_Single_Model_Production.m to define short names hauxtest and httptest.
Bram clarified that 'pendulum length' in P1100090 was exclusive of dpitch, whereas yesterday's version assumed it was equivalent to tl0 which includes dpitch.
Preferred version is now Mathematica 20130628TipTilt or Matlab httpopt_test.m r5013 of 6/28/13. Wiki page is
https://awiki.ligo-wa.caltech.edu/aLIGO/Suspensions/OpsManual/HTTS/Models/20130628TipTilt