I am trying to solve a problem where I am giving an excitation acceleration which is constant 1g to the base of the geometry i.e. fixed (replicating the experiment performed on the shaker). I want to record the FRF of acceleration on the top of the geometry. Can someone tell me how to proceed in such kind of problem.

P.S. I am attaching the geometry of the frame

TIAThe base of all the 4 legs are bolted and fixed