Estimating size of gear tooth root crack using embedded modelling

This paper describes an embedded modelling approach for identifying gear meshing stiffness from measured gear angular displacement or transmission error. An embedded model integrating a physical based model of the gearbox and a parametric representation, in the form of truncated Fourier series, of meshing stiffness is established. A solution method is then used to find the meshing stiffness that minimises the discrepancy between model output and measured output. Furthermore, an algorithm is also developed to estimate the size of tooth crack from identified meshing stiffness. Both simulation and experimental studies were conducted to evaluate if identified tooth meshing stiffness can reveal a tooth crack more effectively, and if the crack size can be estimated with an adequate level of accuracy. (C) 2002 Elsevier Science Ltd. All rights reserved.