In this paper,basis on mechanical structure of certain minor caliber multiple launch rocket system and tactical demand of air defense and antimissile,it is analyzed in detail that friction torque,unbalanced moment,impact moment of burning gas flow and variable rule of moment of inertia,which provide the foundation for more research of position servo system of multiple launch rocket system.

A measurement and compensation method was proposed in order to eliminate the coupling effect on tracking accuracy and stabilizing capability due to unbalanced moment of inertial platform.

The results indicate that we can make sure the unbalance torque of the table according to the range.

Though analysis the dynamic unbalance moment of couple on three ring reducing gear,puts forward the improvement of plan for the bearing liveload Changes the two eccentricity of three ring for three eccentricity of three ring Eliminates dynamic unbalanc emoment of couple and additive liveload on the bearing from three ring reducing gear It provides useful help for design,use and maintenanc