A theoretical and experimental investigation of modulation sidebands of planetary gear sets

In this paper, a simplified mathematical model is proposed to describe the mechanisms leading to modulation sidebands of planetary gear sets. The model includes key system parameters such its number of planets, planet position angles. and planet phasing relationships defined by the position angles and the number of teeth of the gears. The model is used to simulate it wide range of gear sets to show that they can be classified in five distinct groups based oil their sideband behavior in terms of their frequencies and amplitudes. A special experimental planetary gear set-up is developed all(] planetary gear sets front of three of these five groups arc procured. A methodology is developed to demonstrate modulation sidebands from the ring (internal) gear radial acceleration measurements. For each case, sets of ring gear acceleration measurements at various speed and torque conditions are presented to demonstrate rich sideband activity that agrees well with the model predictions. At the end, based oil results of the parametric Studies and experiments. general rules on modulation sidebands of planetary gear sets are proposed. (C) 2009 Elsevier Ltd. All rights reserved.