I have a problem to replicate on Simscape, a theoretical model. By comparing the bode diagram of the theoretical model (left) and the simscape model (right), we can see that the simscape model has a strange behavior in high frequencies.
The output is defined as y(t) = theta(t) + alpha(t)
I suspect the problem comes from the "Revolute1" that I use as a rotational spring in the Multibody part , but I'm not sure and I don't know how I should modify it.
I put in the image the parameters of Revolute1 and the last solid and the mechatronic part, just in case the problem come from there.