A study on comparing acoustic emission and vibration sensors for gearbox fault diagnostics

In recent years, acoustic emission (AE) sensors and AE based techniques have been developed and tested for gearbox fault diagnosis. In general, AE based techniques require much higher sampling rate than vibration analysis based techniques for gearbox fault diagnosis. Therefore, it is questionable if an AE based technique would give a better or at least the same performance as the vibration analysis based techniques using the same sampling rate. To answer the question, this paper presents a comparative study for gearbox tooth damage level diagnostics using AE and vibration measurements, the first known attempt to compare the gearbox fault diagnostic performance of AE and vibration analysis based approaches using the same sampling rate. Partial tooth cut faults are seeded in a gearbox test rig and experimentally tested. Results have shown that AE based approach has the potential to differentiate gear tooth damage levels in comparison with vibration based approach. While vibration signals are easily affected by mechanical resonance, the AE signals show more stable performance.