Dynamic Analysis of a Planetary Gear Failure Caused by Tooth Pitting and Cracking

Planetary gears are widely used in aeronautic and industrial applications that require compactness and high torque-to-weight ratios. Despite these advantages, the severe conditions under which such gears are typically used may lead to failure. Tooth pitting and cracking are frequently encountered failure modes. The defects are modeled and discussed for a planetary gear set. The influence of tooth defects on gear mesh stiffness is scrutinized. Healthy planetary gear dynamic response and the response of planetary gears containing tooth defects are compared in both the time and frequency domains and in the joint time-frequency domains by use of the Wigner-Ville distribution.