Thanks Rich, I agree with you, BUT

PROBLEM 1. if i perform full dynamic analysis, then maximum displacement is amplitude? IS THIS STATEMENT IS CORRECT.

if it is correct which maximum I have to consider as amplitude either DX DY or DZ


PROBLEM 2. For design of ACTUATOR, vendor asking the frequency and amplitude values, and for that system i dont have any dynamic input so what is the solution.
Maximum I can get frequency from modal run what about amplitude.