function [rz] = initializeRz(args)

arguments
  args.type    char    {mustBeMember(args.type,{'none', 'rigid', 'flexible', 'modal-analysis', 'init'})} = 'flexible'
  args.Foffset logical {mustBeNumericOrLogical} = true
end

rz = struct();

switch args.type
  case 'none'
    rz.type = 0;
  case 'rigid'
    rz.type = 1;
  case 'flexible'
    rz.type = 2;
  case 'modal-analysis'
    rz.type = 3;
  case 'init'
    rz.type = 4;
end

% Spindle - Slip Ring
rz.slipring.density = 7800; % [kg/m3]
rz.slipring.STEP    = './STEPS/rz/Spindle_Slip_Ring.STEP';

% Spindle - Rotor
rz.rotor.density    = 7800; % [kg/m3]
rz.rotor.STEP       = './STEPS/rz/Spindle_Rotor.STEP';

% Spindle - Stator
rz.stator.density   = 7800; % [kg/m3]
rz.stator.STEP      = './STEPS/rz/Spindle_Stator.STEP';

rz.K = [7e8; 7e8; 2e9; 1e7; 1e7; 1e7];
rz.C = [4e4; 4e4; 7e4; 1e4; 1e4; 1e4];

if args.Foffset && ~strcmp(args.type, 'none') && ~strcmp(args.type, 'rigid') && ~strcmp(args.type, 'init')
  load('mat/Foffset.mat', 'Fzm');
  rz.Deq = -Fzm'./rz.K;
else
  rz.Deq = zeros(6,1);
end

save('./mat/stages.mat', 'rz', '-append');