function x = sistema(t, x)
x = unicycle(t, x, control_act(t, x));
end
function dx = unicycle(t, x, u)
% u is (v;w)
% x is (x; y; theta)
theta = x(3);
G_x = [cos(theta), 0; sin(theta), 0; 0, 1];
dx = G_x*u;