The acoustic emission (AE) technique is a powerful nondestructive tool for health monitoring of structures and mechanical components, especially due to its sensitivity to capture high frequency signals, which are associated with the early stages of damage development and evolution. The aim of the present work is twofold. The first is the evaluation of a new concept of transducer mounting on rotating structures without the use of the expensive solution of the slip ring. The new concept is realized in a single stage in-house built gearbox setup. The second is the evaluation of the potential of the acquired with the new concept AE signals in distinguishing between different types of artificially induced damage on the gears. Run-in tests were carried out to study the effect of gear damage on the AE recordings. The acoustic emission signature of the healthy gears is first acquired. Then artificial defects are seeded and the acquisition is repeated. The AE signals are analyzed, and their root-mean-square values are calculated. The capability of the new approach of AE acquisition in discriminating between different loading and damage states is shown and discussed. Interesting findings on the effect of the oil temperature on AE recordings only speculated theoretically so far are also presented.

Acoustic Emission is a very powerful tool for health monitoring of structures and mechanical components, especially due to its sensitivity, which is very useful at the early stages of damage evolution. Evaluation of its potential on rotating structures such as gearboxes, is studied in the present paper. A new concept of transducer mounting is realized in a single stage in-house built gearbox. The acoustic emission signature of the healthy gears is acquired. Then artificial defects are seeded and the acquisition is repeated. The signals are afterwards analyzed and the assessment of the applicability of the method becomes possible. Given the present experimental setup, health monitoring of gearboxes using acoustic emission is considered to be of rising potential.

The diagnosis of artificial defects in a single stage gearbox using two non-destructive techniques (vibration and AE) and advanced signal processing techniques to discriminate between different load and defect states is the scope of the present study. Wavelet based techniques were developed and utilised in order to evaluate the vibration signals and extract diagnostic information out of them. A new concept of AE transducer mounting on rotating structures, without the use of the expensive solution of the slip-ring is presented. The AE signals are analyzed and their root-mean-square (RMS) values are calculated. The capability of the new approach of AE acquisition in discriminating between different loading and damage states is shown and discussed. Interesting findings on the effect of the oil temperature upon AE recordings only speculated theoretically so far are also presented. Both methods yielded interesting results and showed an ability to distinguish between healthy and defected gears.