Influence of the position error of planetary gear on the vibrations of a planetary gear system

In planetary gear transmission systems, when the position errors exist between the gear and the axle hole, the vibrations and fatigue life of the systems may be affected. However, the influences of the position errors are rarely considered in the previous dynamic modelling methods for the planetary gear systems (PGSs). To solve this problem, a PGS with six planetary gears is established. The effects of the position errors on the vibrations of PGSs are analysed. Different position error cases between the planetary gears and the planetary shaft are considered in the model, as well as the bearings with the radial clearance. The vibration characteristics from the proposed model with the position errors are compared with those of the normal model. The position errors in the planetary gears of the PGSs can increase its vibration level. This study can provide a new method for detecting the position errors in the PGSs.