Characterisation and evaluation of the harmonic content of involute gear surface deviations

Abstract

Gears are fundamental precision components that are crucial to many industries, including the wind energy sector. They are traditionally analysed using profile and helix line measurements but this does not consider the majority of the contacting surface with intricate surface variations that dictate functional performance. Practical measurement and evaluation of involute gear surfaces remain underexplored. This paper uses the Fourier and wavelet transforms to evaluate measured gear surface deviation harmonic content for a single trace, a trace set, and surface analysis and describes the utility of each. The methods are first demonstrated with synthetic data and then with measured data, then the measured data is simulated in a quasi-static FE tooth contact analysis, which yields insights not solely gleaned from harmonic analysis. The uncertainty of harmonic content analysis is to be established in future work and how that effects the uncertainty of simulated functional performance should be investigated.