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−% LTPDA_MDC1_C returns a frequency-domain model of the controllers for MDC1.
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−%
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−%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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−%
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−% DESCRIPTION: LTPDA_MDC1_C returns a frequency-domain model of the controllers 
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−%              for MDC1.
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−%
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−% CALL:        b = ltpda_mdc1_C(pl)
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−%
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−% PARAMETERS:
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−% 
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−%           'Controller' - Choose controller [default: 'DF']
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−%                        'DF'   - Drag-free controller (including delay)
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−%                        'SUS'  - Suspension controller (including delay)
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−%           'f'        - a vector of frequencies [default: 1]
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−%    or
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−%           'f1'       - start frequency [default: 1e-6]
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−%           'f2'       - stop frequency  [default: 5]
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−%           'nf'       - number of frequency points [default: 1000]
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−%           'scale'    - frequency spacing, 'lin' or 'log' [default: 'log']
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−% 
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−% VERSION:     $Id: ltpda_mdc1_C.m,v 1.3 2008/08/08 13:35:23 anneke Exp $
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−%
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−% The following call returns a parameter list object that contains the
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−% default parameter values:
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−%
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−% >> pl = ltpda_mdc1_C(ao, 'Params')
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−%
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−% The following call returns a string that contains the routine CVS version:
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−%
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−% >> version = ltpda_mdc1_C(ao,'Version')
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−%
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−% The following call returns a string that contains the routine category:
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−%
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−% >> category = ltpda_mdc1_C(ao,'Category')
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−%
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−% HISTORY: 11-04-08 M Hewitson
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−%             Creation
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−%
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−%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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−function varargout = ltpda_mdc1_C(varargin)
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−    %%% Check if this is a call for parameters
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−        if utils.helper.isinfocall(varargin{:})
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−          varargout{1} = getInfo(varargin{3});
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−          return
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−        end
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−
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−        %%% Collect input variable names
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−        in_names = cell(size(varargin));
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−        for ii = 1:nargin,in_names{ii} = inputname(ii);end
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−
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−        pli             = utils.helper.collect_objects(varargin(:), 'plist', in_names);
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−
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−        %%% Decide on a deep copy or a modify
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−        %%% REMARK: If you create a new AO (call the constructor) then
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−        %%%         it is not necessay to copy the input-AOs !!!!!!!!!!!!!!!!!!!!!!!!!
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−
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−
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−        %%% Combine plists
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−        pl = combine(pli, getDefaultPlist('Range'));
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−
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−
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−    %% Extract parameters from plist
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−
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−    f = find(pl, 'f');
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−    if isempty(f)
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−    f1    = find(pl, 'f1');
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−    f2    = find(pl, 'f2');
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−    nf    = find(pl, 'nf');
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−    scale = find(pl, 'scale');
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−
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−    switch scale
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−      case 'lin'
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−        f   = linspace(f1, f2, nf);
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−      case 'log'
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−        f = logspace(log10(f1), log10(f2), nf);
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−    end
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−    end
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−
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−    cont = find(pl, 'Controller');
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−
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−    %% Compute response for frequencies f
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−
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−    switch upper(cont)
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−    case 'DF'
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−      a = getDFcontroller(f);
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−    case 'SUS'
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−      a = getSUScontroller(f);
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−    otherwise
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−      error('### Unknown controller requested.');
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−    end
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−
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−    varargout{1} = a;
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−end
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−%--------------------------------------------------------------------------
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−% Get DF controller for each frequency
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−function o = getSUScontroller(f)
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−
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−  % Compute desired response
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−  T = 0.1;
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−  z = exp(1i*2*pi*f*T);
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−  zi = 1./z;
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−
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−  f1 = -2.4365e-4./(1-exp(-1.0772e-2).*zi);
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−  f2 = complex(1.2115e-4, 3.0511e-5)./(1-exp(complex(-5.5589e-3,-6.4448e-3)).*zi);
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−  f3 = complex(1.2115e-4, -3.0511e-5)./(1-exp(complex(-5.5589e-3, 6.4448e-3)).*zi);
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−  f4 = 1.0741e-6./(1 - 1.*zi);
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−
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−  % Controller delay
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−  s = 1i*2*pi*f;
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−  dt = 305/1000;
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−  D = (exp(-s.*(T+dt)) .* (-1+exp(s.*T))  )./(s.*T);
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−
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−  H = 0.1.*( f1 + f2 + f3 + f4).*D;
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−
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−  % Create fsdata object
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−  fsd = fsdata(f, H);
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−
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−  % Create an AO
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−  o = ao(fsd);
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−  o.setXunits('Hz');
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−  o.setYunits('N/V');
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−  o.setName('C_{sus}');
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−end
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−%--------------------------------------------------------------------------
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−% Get DF controller for each frequency
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−function o = getDFcontroller(f)
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−
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−  % Transform from f to z
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−  T = 0.1;
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−  z = exp(1i*2*pi*f*T);
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−  zi = 1./z;
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−
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−  % Compute individual terms in the frequency series
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−  f1 = -1.61./(1-exp(-0.30943).*zi);
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−  f2 = complex(0.86807, 0.12606)./(1-exp(complex(-9.753e-2,-1.6175e-1)).*zi);
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−  f3 = complex(0.86807, -0.12606)./(1-exp(complex(-9.753e-2,1.6175e-1)).*zi);
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−  f4 = -complex(6.4699,70.435)./(1-exp(complex(-5.5289e-5,-4.8946e-6)).*zi);
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−  f5 = -complex(6.4699,-70.435)./(1-exp(complex(-5.5289e-5,4.8946e-6)).*zi);
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−  f6 = 12.946./(1 - 1.*zi);
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−
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−  % Controller delay
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−  s = 1i*2*pi*f;
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−  dt = 315/1000;
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−  D = (exp(-s.*(T+dt)) .* (-1+exp(s.*T))  )./(s.*T);
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−
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−  % Combine all terms into a single response
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−  H = 0.1.*( f1 + f2 + f3 + f4 + f5 + f6 ) .* D;
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−
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−  % Build a frequency-series data object
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−  fsd = fsdata(f, H);
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−  
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−  % build the AO and set its name
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−  o = ao(fsd);
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−  % Set X-units, Y-units and name to something meaningful
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−  o.setXunits('Hz');
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−  o.setYunits('N/V');
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−  o.setName('C_{df}');
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−end
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−
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−%--------------------------------------------------------------------------
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−function plo = getDefaultPlist(varargin)
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−  % List of available parameter sets
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−  sets = {'List', 'Range'};
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−
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−  if nargin == 0
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−    plo = sets;
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−    return
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−  end
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−
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−  set = varargin{1};
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−
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−  switch set
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−    case 'List'
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−      plo = plist('Controller', 'DF', 'f', [1]);
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−    case 'Range'
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−      plo = plist('Controller', 'DF', ...
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−                  'f1', 1e-6,...
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−                  'f2', 5,...
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−                  'nf', 1000,...                
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−                  'scale', 'log');
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−    otherwise
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−    plo = plist();
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−  end
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−end
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−%--------------------------------------------------------------------------
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−function ii = getInfo(varargin)
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−  if nargin == 1 && strcmpi(varargin{1}, 'None')
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−    sets = {};
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−    pl   = [];
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−  else
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−    sets = {'Default'};
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−    pl   = getDefaultPlist;
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−  end
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−  % Build info object
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−  ii = minfo(mfilename, 'CLASS', '', 'CATEGORY', '$Id: ltpda_mdc1_C.m,v 1.3 2008/08/08 13:35:23 anneke Exp $', sets, pl);
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−end
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−
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−
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−