Hi Puja,
The issue you are facing is because of the function definition and the initial conditions provided. The 'y0' variable is defined as [1; 0], but the system has four variables (displacements and velocities for two masses). You need to provide initial conditions for all four variables.
Please follow the below-mentioned example MATLAB code to correctly simulate the mass-spring system:
% Define the mass-spring system function
function fval = massSpringFun(t, y)
% Extract variables
x1 = y(1);
v1 = y(2);
x2 = y(3);
v2 = y(4);
% Define constants
m = 1;
c = 0.001;
k = 100;
h = 0.01;
% Define dy/dt
fval(1, 1) = v1;
fval(2, 1) = (k/m) * (x1 - x2) - (c/h) * v2;
fval(3, 1) = v2;
fval(4, 1) = 0; % Assuming no external force on the second mass
end
Providing initial conditions for all the four variables:
% Initial conditions for all four variables
y0 = [1; 0; 0; 0];
% Time span
tspan = [0, 10];
% Solve the ODE system
[tsol, ysol] = ode45(@massSpringFun, tspan, y0);
% Plot the displacement of the first mass
plot(tsol, ysol(:, 1));
xlabel('Time');
ylabel('Displacement (x1)');
title('Mass-Spring System');
grid on;
I hope this helps to solve your query!
