function [ry] = initializeRy(opts_param)
    %% Default values for opts
    opts = struct('rigid', false);

    %% Populate opts with input parameters
    if exist('opts_param','var')
        for opt = fieldnames(opts_param)'
            opts.(opt{1}) = opts_param.(opt{1});
        end
    end

    %%
    ry = struct();

    ry.m = 200; % [kg]

    if opts.rigid
        ry.k.tilt = 1e10; % Rotation stiffness around y [N*m/deg]
    else
        ry.k.tilt = 1e4; % Rotation stiffness around y [N*m/deg]
    end

    ry.k.h    = 357e6/4; % Stiffness in the direction of the guidance [N/m]
    ry.k.rad  = 555e6/4; % Stiffness in the top direction [N/m]
    ry.k.rrad = 238e6/4; % Stiffness in the side direction [N/m]

    ry.c.h    = 10*(1/5)*sqrt(ry.k.h/ry.m);
    ry.c.rad  = 10*(1/5)*sqrt(ry.k.rad/ry.m);
    ry.c.rrad = 10*(1/5)*sqrt(ry.k.rrad/ry.m);
    ry.c.tilt = 10*(1/1)*sqrt(ry.k.tilt/ry.m);

    %% Save
    save('./mat/stages.mat', 'ry', '-append');
end