Hello AndreaEnid,
Base acceleration is used to simulate the input a structure might see in an earthquake or when sitting on a vibrating rigid surface like an engine block or a shaker table top.
Can you provide an image of the structure you are working on. I don't understand your "rotational base constraint". Do you mean you have a revolute joint that you added a spring to add rotational stiffness?
Regards,
Peter
You are navigating away from the AIS Discovery experience