Two DOF system

clear; close all2 DOF model

eta=1.0;
k1=(0.1592*2*pi)^2;
k2=(0.3*2*pi)^2;
c1=0.008;
c2=0.01;
m1=1;
m2=1;
alpha=0.0;
beta=3.0;

Fs=5; % Sampling frequency, [Hz] t_stop=6e2;2 DOF solution

sim(‘s22′, t_stop); % Simulate a Simulink model
figure(1);
subplot(211)
plot(y1,’b’);
axis tight
ylabel(‘1st mode’);
subplot(212)
plot(y2,’k’);
axis tight
xlabel(‘Points’); ylabel(‘2nd mode’);
title([‘Free vibration, \eta=’ num2str(eta) ‘, k1=’ num2str(k1) ‘, k2=’ num2str(k2) ‘, c1=’ num2str(c1)]);