How approximate derivative of signals with linear combinations of the unstable time varying linear filter ?

Hi, I am currently working on a Simulink block designed to estimate time derivative via parameter identification of a certain signal. This block is created to estimate the first derivative of y=exp(sin(3t)). Inside of state linear filter ,i try to follow the state representation given by http://www.lix.polytechnique.fr/fliessconf/Slides/SiraRamirez.pdf,But the simulation give me a divergent signal. Can someone show me how to find resolve this problem or there is another way to approximate this derivatives? Thanks in Advance.