function dv = quartercar(t,vvec)
k1 = 5300;
k2 = 163000;
m1 = 470;
m2 = 50;
c1 = 310;
c2 = 1200;
v_param = 65/3.6;
H_param = 0.2;
v = 65/3.6;
L = 1;

if t > L/v
    h = 0;
    h_prick = 0;
else
     h = (H_param/2)*(1-cos((2*pi*v_param*t)/L));
     h_prick = (pi*H_param*v_param*sin((2*pi*v_param*t)/L))/L;
end
H = [0 0 1 0; 0 0 0 1; (-k1/m1), (k1/m1), (-c1/m1), (c1/m1); k1/m2, -((k1+k2/m2)), c1/m2, -((c1+c2)/m2)];
g = [0;0;0;((k2*h)/m2) + ((c2*h_prick)/m2)];


dv = H*vvec + g;
end