RUL prediction approach to fatigue crack based on physics model for planetary gear set of helicopter

Abstract 

Malfunction of helicopter transmission system commonly cause momentous loss of life and economy. To avoid the accident of helicopter, it is an effective selection to develop the techniques on prognostics and health management (PHM) for helicopter transmission system. As an important aspect of PHM, residual useful life (RUL) prediction is a particularly challenging. Currently, the research object of RUL prediction still focuses on the critical part in complex mechanical system. Aiming at the root fatigue crack in planetary gear set of main transmission system of helicopter, a methodology based on physics model is presented to predict residual useful life. First to the research, the feature parameters suitable for RUL prediction were selected by a statistical algorithm and test data. After that, Paris Equation was modified and used to predict the RUL of root fatigue crack in sun gear of planetary gear set. Finally, the run-to-failure test was carried out and the test data validation has a promising result.