In this paper the method of improving the dynamic character of servo system for accurate positioning of the excutive mechanism is described.Using precision rotary pedestal with 3 axes as an example

both dynamical behauiovr of mechanical structure and frequency character of servo system are discussed simultaneously based on integrated mechanics and electric

by means of FEM

modal analysis and modal synthesis

and the unified mathematical model is founded.On the basis of solution.the sensitive factors to affect the stabilization of servo system are provided.The method of improving stabilization and the optimum design can be carried out.