Vibration-based fault detection of meshing shafts. Issue 21 (2015)

• Record Type: Journal Article
• Authors: Girondin, Victor; Morel, Herve; Cassar, Jean-Philippe; Pekpe, Komi Midzodzi
• Is Part Of: IFAC-PapersOnLine. Volume 48:Issue 21(2015)
• Page Start: 560
• Page End: 565
• Publication Date: 2015
• Subjects: vibration -- helicopter -- health monitoring -- shaft -- HUMS; Automatic control -- Periodicals; 629.805
• DOI: 10.1016/j.ifacol.2015.09.585
• Languages: English
• ISSNs: 2405-8963

Abstract

Abstract: In this article, vibration-based monitoring of cracked shafts is addressed in the context of mechanical transmission of helicopters. The approach developed is based on the detection of cyclostationary components produced by a crack. The cyclostationary theory is first presented on a mechanical point of view. Then a signal processing indicator, the spectral coherence, is introduced in order to quantify the second order cyclostationary content of a signal. The characteristics of the vibration produced in the faulty case are explained from a mechanical model of a cracked shaft. It is then shown that small variations in the structural parameters of the crack creates cyclostationary modulations around the meshing frequencies. This justifies the spectral coherence as a relevant indicator to monitor the crack. The spectal coherence is successful applied on bench data reproducing a crack propagation on an actual helicopter shaft.