Claudio Pedrazzi

Hi, please don't misunderstand my suggestion, I like APDL very much, but since you are in Workbench already, why not define an additional small body (e.g. a small cube), add a point mass on it, and connect it with a spring (it is available and has even damping, if you need it).  Possibly you should constrain the body so that it can move only in the appropriate direction (Y, judging from your screenshot)