Hybrid Modeling and Spectrum Analysis of Helicopter Planetary Gearbox Fault Based on Dynamics

The helicopter transmission system is a key component that connects the powertrain and rotor without redundancy. Once the transmission system fails or loses efficacy, it will directly affect flight safety. A typical crack damage dynamic model is established for the planetary gear set of a helicopter transmission system utilizing the lumped-parameter method. A hybrid simulation model of measuring point on the top of the planetary gearbox is built based on mixing the mathematical modeling of the transmission effect by using finite element technology and the dynamic model. The analysis results demonstrate that the proposed model is effective for crack damage response simulation.