Creating an articulated beam (simple supported) with spring attached

[Joa Chi Lang, Christopher.]

Good morning, 

I am creating a model with an aticulated beam with a mass and spring attached to the end. I added an initial displacement of 0.01 m, but I am getting an odd response (a response with an amplitude different to 0.01 m when there is not any initial velocity and the amplitude of the response should be the same as the initial displacement as you can see in the formula sheet I attached).

I am running on PyChrono. Please let me know if you have any advise or feedback.