I. Introduction
The dynamics main problem of water surface warship PRDS is to determine its dynamic excitation. The key is to establish gear meshing coupling vibration model in analyzing warship PRDS dynamics. Early gear dynamics model was single degree of freedom, which was mainly to determine gear teeth meshing dynamic load factor [1]– [3]. The gear lateral vibration displacement was not considered and the support was assumed to be rigid [4]– [6], the gear pair torsional vibration model was mainly studied in gear pairs dynamic meshing. Especially for dynamic excitation results, were very crucial for gear pairs torsional vibration, which played an important role in warship PRDS stability.