How to set up a model that rotates at a certain frequency in HFSS 9.2?

Hi, all,

I am a beginner of the ansoft HFFS my version is 9.2.
I am doin a project regarding antenna in Reverbration chamber. I am trying to create a platform stirring technique in the chamber. I dunt noe how to set up a model like a stepper motor that a rotate at a certain frequency.

Is there anyone can help?

Thanks very much!